A M35 helmet on display inside the Historisch Museum Rotterdam in Rotterdam.
|Place of origin||Germany|
|Used by||See Users|
|Wars||World War I|
Chinese Civil War
World War II
Stahlhelm (plural Stahlhelme) is German for "steel helmet". The Imperial German Army began to replace the traditional boiled leather Pickelhaube (spiked combat helmet) with the Stahlhelm during World War I in 1916. The term Stahlhelm refers both to a generic steel helmet, and more specifically to the distinctive (and iconic) German design.
The Stahlhelm, with its distinctive "coal scuttle" shape, was instantly recognizable and became a common element of military propaganda on both sides, just like the Pickelhaube before it. Its name was also used by the Stahlhelm, a paramilitary nationalist organization established at the end of 1918.
After the war, the German Bundeswehr continued to call their standard helmet Stahlhelm, but the design was based on the American M1 helmet. The Bundesgrenzschutz, however, continued to use the original German design, until either troop switched to the new M92 Aramid helmet.[clarification needed]
At the beginning of World War I, none of the combatants were issued with any form of protection for the head other than cloth and leather caps, designed at most to protect against saber cuts. When trench warfare began, the number of casualties on all sides suffering from severe head wounds (more often caused by shrapnel bullets or shell fragments than by gunfire) increased dramatically, since the head was typically the most exposed part of the body when in a trench. The French were the first to see a need for more protection--in late 1915 they began to issue Adrian helmets to their troops. The British and Commonwealth troops followed with the Brodie helmet (a development of which was also later worn by US forces) and the Germans with the Stahlhelm.
As the German army behaved hesitantly in the development of an effective head protection, some units developed provisional helmets in 1915. Stationed in the rocky area of the Vosges the Army Detachment "Gaede" recorded significantly more head injuries caused by stone and shell splinters than did troops in other sectors of the front. The artillery workshop of the Army Detachment developed a helmet that consisted of a leather cap with a steel plate (6 mm thickness). The plate protected not only the forehead but also the eyes and nose.
The design of the Stahlhelm was carried out by Dr. Friedrich Schwerd of the Technical Institute of Hanover. In early 1915, Schwerd had carried out a study of head wounds suffered during trench warfare and submitted a recommendation for steel helmets, shortly after which he was ordered to Berlin. Schwerd then undertook the task of designing and producing a suitable helmet, broadly based on the 15th-century sallet, which provided good protection for the head and neck.
After lengthy development work, which included testing a selection of German and Allied headgear, the first Stahlhelms were tested in November 1915 at the Kummersdorf Proving Ground and then field tested by the 1st Assault Battalion. Thirty thousand examples were ordered, but it was not approved for general issue until New Year of 1916, hence it is most usually referred to as the "Model 1916". In February 1916 it was distributed to troops at Verdun, following which the incidence of serious head injuries fell dramatically. The first German troops to use this helmet were the stormtroopers of the Sturm-Bataillon Nr. 5 (Rohr), which was commanded by captain Willy Rohr.
In contrast to the Hadfield steel used in the British Brodie helmet, the Germans used a harder martensitic silicon/nickel steel. As a result, and also due to the helmet's form, the Stahlhelm had to be formed in heated dies at a greater unit cost than the British helmet, which could be formed in one piece.
Germany exported versions of the M1935 helmet to various countries. Versions of the M1935 Stahlhelm were sent to Republic of China from 1935 to 1936 and M1935 helmet was the main helmet of the Chinese Nationalist Army during World War II. Spain also received shipments of the helmet. During the inter-war years several military missions were sent to South America under the command of Hans Kundt, after Chaco War the Bolivian army used to wear the helmet up until recently. The exported M1935 helmets were similar to the German issue, except for a different liner.
Some countries manufactured their own helmets using the M1935 design, and this basic design was in use in various nations as late as the 1970s.
The Germans allowed and assisted the Hungarians in copying their design of the M1935 steel helmet. Therefore, the WWII-produced M38 Hungarian steel helmet is nearly identical to the German M1935. Both have the same shape, riveted ventilation holes, and the classic rolled edge. Differences include a different liner and different rivets position - the cotter pins are situated behind the ventilation holes. A square metal bracket is riveted on the rear, above the back brim; used to secure the helmet to the knapsack while marching. It was typically painted in Hungarian brown-green, albeit blue-grey versions existed. It is sometimes called the "Finnish M35" due to their extensive use by the Finnish Army during the Continuation War 1941-44.
After the end of World War I Poland seized large quantities of M1918 helmets. Most of those were later sold to various countries, including Spain. However, at the end of the 1930s it was discovered that the standard Polish wz. 31 helmet was unsuitable for tank troops and motorized units; while offering decent protection, it was too large and heavy. As a stop-gap measure before a new helmet was developed, the General Staff decided to issue M1918 helmets to the 10th Motorized Cavalry Brigade, which used them during the Polish Defensive War.
During the time of the Warsaw Uprising the helmet was also worn by the members of the Polish Home Army and it was during this time that the helmet became the symbol of the resistance, as every Stahlhelm worn by the soldier of the underground army signified a dead German occupier it was taken from.
In November 1926, the Irish Defence Forces decided upon adopting the German Stahlhelm helmet. However when the Irish government contacted German Foreign Office with a request for a sample they were informed that Germany was barred from exporting steel helmets by the Treaty of Versailles. The Irish then turned to London based Vickers, ordering 5,000 copies of a model closely resembling the M1918 helmet. The helmet remained in use until it was replaced by the British Mark II model in 1940. Following the outbreak of World War II, the helmets became the subject of anti-Irish propaganda originating in Britain. A large number of the withdrawn helmets were reissued to various emergency services after being painted white.
Switzerland used a helmet, designated the M1918, that was roughly similar to the M1916, but had a shallower, wider and more rounded crown and skirt. This was to protect against the harsh winter winds of the alpine regions.
The Chilean Army was a prolific user of the Vulkanfiber models, bought before the Second World War, along with a few M1935 and Czechoslovak M1932 helmets. After the war, local production started, with plastic models still in ceremonial & garrison use today. Small runs of steel helmets were made by FAMAE in the 80's, but ultimately were not adopted due to the ascendance of kevlar helmets by that time . A Stahlhelm with crossed bayonets and the corresponding number is the standard insignia of infantry regiments.
The Argentine Army adopted a similar model, made of pressed fiber, during World War II, reflecting the traditional sympathy towards Germany found in many of the officers. For combat and provincial police use, imported Swiss M1918 helmet were still in service as late as 1976.
In the Socialist Federal Republic of Yugoslavia, due to large quantities captured by World War II Partisans, the Stahlhelm was used in Yugoslav People's Army up to 1959, when it was phased out and replaced by the M59/85 steel helmet.
After World War II, West Germany's Bundesgrenzschutz border guards and some West German police units kept the Stahlhelm in their inventories (police units can be seen wearing them during footage of the Black September hostage crisis in 1972), and the Fallschirmjäger variant was used for some time by the GSG 9. With the re-armament of West Germany the Bundeswehr introduced the United States Army M1 Helmet which was replaced by a Kevlar helmet (Gefechtshelm), similar to the modern US helmets, in the 1990s. German firefighter units today still use Stahlhelm-shaped helmets in a fluorescent color.
East Germany's National People's Army M-56 helmet was modelled on an unused 1942 German design with a more conical shape. The Chilean Army still uses the Stahlhelm design for ceremonial purposes, as well as the Bolivian Army. There are also some Japanese bicycle helmets (with accompanying goggles) that resemble the Stahlhelm. Many schools and universities in Mexico such as the Autonomous University of Baja California have military bands that use or resemble the M35 Stahlhelm.
The U.S. Army's 1980s and 1990s era Kevlar Personnel Armor System for Ground Troops Helmet was sometimes called the "Fritz helmet" for its resemblance to the Stahlhelm. The U.S. Army and Marines have continued to use a design akin to the PASGT helmet with the MICH TC-2000 Combat Helmet and Lightweight Helmet, respectively.
Since 2012, El Salvador's Policia Nacional Civil use a navy/indigo blue-coloured helmet that strongly resembles the Stahlhelm; this helmet is used by some members of the riot-control unit and rarely used by the Police's assault teams.
Chilean honour guard next to U.S. Admiral Michael G. Mullen in March 2009
Argentinian army use of the Swiss M1918 helmet, 1930s-1940s
Chinese soldiers of the National Revolutionary Army wearing Stahlhelms
German Civil defence stahlhelm with wider, flared peak in use from the 1940s until the 1990s
Ukrainian Euromaidan protester wearing stahlhelm, 2014. The inscription says "Putin, think or you'll end up like Hitler".
The different Stahlhelm designs are named for their year of introduction. For example, the Modell 1942 which was introduced in 1942 is commonly known as M1942 or simply M42. Here, they are referred to by their M19XX names.
The Stahlhelm was introduced into regular service during the Verdun campaign in early 1916.
The M1916 design had side-mounted horn-like ventilator lugs which were intended to be support for an additional steel brow plate or Stirnpanzer, which only ever saw limited use by snipers and trench raiding parties, as it was too heavy for general use.
The shell came in different sizes, from 60 to 68, with some size 70s reported. Helmet weight varied from 0.98 kg to 1.4 kg, depending on shell size. The suspension, or liner, consisted of a headband with three segmented leather pouches, each holding padding materials, and leather or fabric cords could be adjusted to provide a comfortable fit. The one-piece leather chin strap was attached to the shell by M1891 chinstrap lugs, the same kind used in the Pickelhaube helmet.
The M1916 design provided excellent protection: Reserve Lieutenant Walter Schulze of 8th Company Reserve Infantry Regiment 76 described his combat introduction to the helmet on the Somme, 29 July 1916:
... suddenly, with a great clanging thud, I was hit on the forehead and knocked flying onto the floor of the trench... a shrapnel bullet had hit my helmet with great violence, without piercing it, but sufficiently hard to dent it. If I had, as had been usual up until a few days previously, been wearing a cap, then the Regiment would have had one more man killed.
But the helmet was not without its flaws. The ventilator horns often let cold air in during the winter, requiring the wearer to block the vents with mud or fabric. The large, flared skirt tended to make it difficult for soldiers to hear, distorting surrounding sounds and creating an echo when the wearer spoke.
Originally painted Feldgrau (field grey), the Stahlhelm was often camouflaged by troops in the field using mud, foliage, cloth covers, and paint. Official issue cloth covers in white and grey appeared in late 1916 and early 1917. Camouflage paint was not formally introduced until July 1918, when German Army Order II, No 91 366, signed by General Erich Ludendorff on 7 July 1918, outlined official standards for helmet camouflage. The order stipulated that helmets should be painted in several colors, separated by a finger-wide black line. The colors should be relevant to the season, such as using green, brown and ochre in summer.
After the effectiveness of the M1916 design was validated during the 1916 campaigns, incremental improvements were subsequently made. The M1917 version saw improvements to the liner, but was otherwise identical to the original design.
Extensive redesigns were made for the M1918 model. A new two-piece chin strap was introduced, and was attached directly to the helmet liner rather than the shell. Certain examples of the M1918 had cutouts in the rim along the sides of the helmet. It has incorrectly been said that these cutouts were to accommodate using headphones while wearing the helmet. These cutouts were actually done to improve hearing and to reduce echo created by the large, flared skirt.
The M1918 Stahlhelm can be distinguished from the M1916, as the M1918 shell lacks the chinstrap rivet on the lower side of the helmet skirt found on earlier models.
Austria-Hungary purchased about 416,000 German helmets from November 1916 until the end of the war and also began its own licensed production starting in May 1917. Around a million Stahlhelms of all variants were issued until the end of the war.
The Austrian M17 helmet was similar to the German M16, but was colored golden-brown (known as Isonzo-braun), had a cloth chinstrap and had the chinstrap rivet located higher up on the steel shell. From May 1917 till the end of World War I 534,013 were produced, many of which were manufactured at the Krupp in Berndorf, Lower Austria. Other production locations included:
The Hungarian M18 variant was similar to the Austrian M17 design, but the chinstrap rivet was smaller in size and located even higher up than the Austrian version. It was colored in golden-brown (known as Isonzo-braun). These were manufactured at the Krupp in Berndorf, Lower Austria.
Germany delivered 5,400 visorless versions of the M1918 helmet for the Ottoman Empire. The missing front visor was thought by the Germans to be for religious reasons, and it was claimed that it was to allow Turkish soldiers to touch their foreheads to the ground during prayer, without removing their helmets. However, this story has been disputed. The Turks rejected any more than the 5,400 delivered and an unknown number from the overrun were issued to German armed forces and were used by German Freikorps units after the war.
In 1932 the Army High Command ordered the testing of a new prototype helmet intended to replace the older models. It was made entirely from a composite plastic material called "Vulkanfiber". The Model 1933 Vulkanfiber helmet kept the basic form of previous helmets, but was much lighter. It was put into limited production following favourable field tests in early 1933 and small numbers were issued to Reichswehr infantry, artillery and communications units. It was removed from service following the introduction of the M1935 helmet and most of the remaining stock were reissued to civil organizations such as fire brigades and police forces. Some examples were also retained for parade use by senior officers, who were not generally issued with the Stahlhelm.
In 1934 tests began on an improved Stahlhelm, whose design was a development of World War I models. The Eisenhüttenwerke company[clarification needed] of Thale carried out prototype design and testing, with Dr. Friedrich Schwerd once again taking a hand.
The new helmet was pressed from sheets of molybdenum steel in several stages. The size of the flared visor and skirt was reduced, and the large projecting lugs for the obsolete armor shield were eliminated. The ventilator holes were retained, but were set in smaller hollow rivets mounted to the helmet's shell. The edges of the shell were rolled over, creating a smooth edge along the helmet. Finally, a completely new leather suspension, or liner, was incorporated that greatly improved the helmet's safety, adjustability, and comfort for each wearer. These improvements made the new M1935 helmet lighter, more compact, and more comfortable to wear than the previous designs.
The Army's Supreme Command within the Third Reich's Wehrmacht combined armed forces officially accepted the new helmet on June 25, 1935 and it was intended to replace all other helmets in service.
More than 1 million M1935 helmets were manufactured in the first two years after its introduction, and millions more were produced until 1940 when the basic design and production methods were changed.
In 1938, the Germans developed a variant of the Stahlhelm with a wider, flared peak and ventilation holes originally intended for firefighters, civil defense, Reichsarbeitsdienst, and Luftschutz personnel. Known as the gladiator pattern, the privately purchased Luftschutz helmet was originally made from three pieces of steel and typically painted black or dark blue. Later in the war these were issued to Volkssturm personnel, and sometimes repainted in Feldgrun. By 1944, the helmets were stamped from a single steel sheet, and the original cloth lining replaced with vinyl to reduce costs. Due to the relatively small number produced, original helmets from the war years are considered rare. However, a modified postwar version in fluorescent green, white or yellow continued to be issued to rescue workers in the Bundesrepublik until the early 1990s.
The M1935 design was slightly modified in 1940 to simplify its construction, the manufacturing process now incorporating more automated stamping methods. The principal change was to stamp the ventilator hole mounts directly onto the shell, rather than utilizing separate fittings. In other respects, the M1940 helmet was identical to the M1935. The Germans still referred to the M1940 as the M1935, while the M1940 designation were given by collectors.
A variant of the M1935 helmet with a shell lacking the projecting visor and deep, flared rim was issued to Fallschirmjäger (German paratrooper) units. It was so designed in order to lessen the risk of head injury on landing after a parachute jump; also to reduce the significant wind resistance and resulting neck trauma. Early Fallschirmjäger helmets were manufactured from existing M1935 helmets by removing the undesirable projections, which were omitted when the new design entered full production. The modified shell also incorporated a completely different and more substantial liner and chinstrap design that provided far more protection for German airborne troops. The chinstrap featured a four-point retention system that has come into use again by modern combat helmets such as the MICH since the late 1990s.
The M1942 design was a result of wartime demands. From direct orders of the Führer, to 'maintain intimidation but reduce cost'. The rolled edge on the shell was eliminated, creating an unfinished edge along the rim. This edge slightly flared out, along the base of the skirt, reducing the protection the helmet gave. The elimination of the rolled edge expedited the manufacturing process and reduced the amount of metal used in each helmet. Shell paint colors were typically matte grey-green (Heer) or grey-blue (Luftwaffe), and the decals were eliminated in 1943 to speed up production and reduce the helmet's combat visibility. Greater manufacturing flaws were also observed in M1942 helmets made late in the war.
A simpler variant, designed in 1942 by the Institute for Defence Technical Materials Science in Berlin, was also stamped out of one piece of metal, but with sloped sides. It was similar in appearance to the British 1944 Type Mk III helmet.
There have been reports of a variant manufactured in the last months of the war. The M1945 was reported to have been similar to the M1942 design, but did away completely with the ventilator. These helmets are reported to be extremely rare. Many collectors and historians are of the opinion that the M1945 helmet is just a regular M1942 helmet that lacked the vents simply because of machine malfunctions in the factory, or unfinished M1942 that were completed in the post-war era.
A variant of the M1944 with a modified suspension system, developed further into the M1956.
The East German M-56 helmet was originally designed in 1942 as a replacement for the M1935/M1940 model Stahlhelm. It was initially developed for the Wehrmacht by the Institute for Defense Technical Materials Science in Berlin (see M1944 above). The helmet had seen trials since 1943, but was not adopted during World War II.
The design was not used until the requirement for a distinct German helmet for the Volkspolizei and the National People's Army arose. The East German leadership was motivated in large part by a desire to avoid provoking the offence that using a traditional Stahlhelm design would have caused East Germany's Warsaw Pact allies (especially Czechoslovakia, Poland and the Soviet Union), but a more practical military necessity was also present due to the continued use of surplus Stahlhelms by West German units, in particular border guards. Moreover, the East Germans suspected the West could re-issue the Stahlhelm on a general basis in the Bundeswehr at any time and therefore needed a helmet that was easily distinguishable from that of their potential enemy. For both reasons, the 1942 design was likely chosen because it was the most similar of all German designs to the most recognizable Soviet helmets, in particular the iconic SSh-40 design. Such a design not only served a political purpose, but was one that NATO armies were unlikely to closely duplicate. Indeed, the M-56 was similar enough in appearance to the SSh-40 that some Westerners failed to realize its German origins altogether and assumed the East Germans had adopted a Soviet design.
The M-56 helmet came in three basic versions, Mod 1 or I/56, Mod 2 or I/57 and Mod 3 or I/71, and was widely sold (or given) to Third World armies.
The West German M-56 Stahlhelm was a direct copy of the U.S. M1 helmet. It was properly called "zweiteiliger Stahlhelm" (two-piece steel helmet). In 1958 the helmet was made as a one-piece helmet and renamed Stahlhelm M1A1. The M1A1 came in three sizes: 66, 68, and 71. This helmet was used until 1981 when a modified version was released and renamed the Helm1A1. Modifications included a 3-point chin strap with the third point connecting at the nape, extra large sizes, and a further adjustable liner.
After Stahlhelm shells were painted, the colours of which varied by organization, small identification or insignia decals usually were affixed to one or both sides of the helmet. Almost every military, naval, and political organization had its own distinctive insignia, which was applied as decals to the sides of helmets. The right side of early M35 helmets bore the tricolored shield of black, white, and red stripes, the traditional national colors of the pre-WWI German Empire (cf. the black, red, and gold of today's Federal Republic of Germany, harking back to the 1848 Revolt). The left side of the shell often received decal insignia denoting the branch of the armed forces, or Wehrmacht, or an organization within the Nazi Party.
The combined Wehrmacht military forces of Nazi Germany consisted of the Heer (army), the Kriegsmarine (navy), and the Luftwaffe (air force). While not technically part of the Wehrmacht, the Waffen-SS ("Armed-SS") tactically operated as such and was considered part of Germany's armed forces during the war. The same was true of some Sturmabteilung (SA) units, along with other subsidiary organizations, which functioned as part of the armed forces particularly towards the end of the war. Wehrmacht branches typically displayed distinctive emblems in the form of decals on their helmets. The Heer, or army, displayed a black shield bearing the frontal view of a silver-colored German eagle holding a swastika in its talons (known as the Reichsadler), while the navy used the same eagle emblem in gold. Luftwaffe decals displayed the side view of an eagle in flight, also holding a swastika. The SS was both a paramilitary and a political organization, and its black runic initials on a silver-colored shield (normally applied to the right side of the shell) looked like twin lightning bolts. Other military, political, and civil or defense organizations used similar decal insignia to distinguish their helmets. Such visible identification devices were gradually abandoned as the war progressed, however, so that by war's end most Wehrmacht helmet insignia had been eliminated to reduce the wearer's visibility in combat.
For the Chinese Nationalist Army soldiers, their M35 helmets were printed with the Chinese Nationalist Insignia in both sides.


Alternative Energy Sources (E162076)
|Departments:||ústav techniky prostředí (12116)|
|Valid until:|| ??||Range:||2P+1C|
Principles and basics of alternative energy sources applications. Solar energy. Heat pumps. Biomass utilization.
Solar energy. Photothermal conversion of solar radiation. Solar collectors. Solar thermal systems - design and balancing.Solar systems components and their design. Heat pumps and components. Heat pump coefficient of performance. Heat pump operation. Sources of low potential heat for heat pumps (air, water, ground, waste heat). Design of low potential heat sources. Energy use of biomass. Types of biomass (fytomass, animal, waste). Termochemical conversion of biomass. Combustion and combustion boilers.
Structure of tutorial
Geometry of solar radiation. Efficiency and thermal output of solar collector. Dimensioning of solar collector area for water heating systems. Energy gains calculation. Heat pump cycle in diagramm pressure-enthalpy. Dimensioning of low-potential heat sources for heat pumps (ground bore holes and flat collectors, wells, waste air). Design of heat pump for heating (heat load, heating water temperature). Dimensioning of biomass fuel store.
Matuška, T.: Handbook of designer - Solar thermal systems, STP Praha 2009.
Dvořák, Petrák: Tepelná čerpadla.
Matuška, T.: Alternative energy sources, CTU 2010. Education texts on internet.
Basics of thermal engineering.
Subject Environmental Engineering.


Mollies are more difficult to keep healthy and happy than other "beginner fish" like their close relatives the guppies and the platys. They have smaller broods than many live-bearing fish, but still breed prolifically. If you want to try your hand at breeding mollies -- or if you want to be sure yours don't breed -- you will first have to learn how to distinguish between their sexes. Several clues can help you tell male from females, whether they're balloon mollies or other species.
The easiest way to tell a male molly from a female is by looking at the anal fin. If you start at the back of the fish and move forward, the anal fin is the first fin on the bottom of the fish. In the case of balloon mollies with their rounded bodies, this fin points the same direction as the caudal or tail fin. In females, the anal fin is a regular triangular fin. In male balloon mollies, the fin is rolled into a tube-shaped organ called the gonapodium. If a fish has its fins clamped against its body, it might be hard to spot, but this is still the best way to tell male mollies from females.
In most livebearers, the body shape can help distinguish males from females. However, the distinction is less pronounced in balloon mollies. In general, female livebearers are more rounded than their male counterparts, particular at the rear margin of the abdomen. In balloon mollies, females do have more rounded bodies. But with these particular fish, it takes a bit more practice to tell the difference between a rounded male and a slightly more rounded female. You can use this as a backup for checking the anal fin.
Male mollies have larger dorsal fins than females. The dorsal fin is the back fin -- think of the movie "Jaws" if you get confused on this. Males use their larger dorsal fins for attracting the females. However, just like the body shape, the difference is less pronounced in the balloon molly than in other species and varieties of mollies. Combine this observation with those of body shape and anal fin shape to confirm your observations.
You can determine males from females by their behavior, too. Male mollies, like most livebearers, are constantly trying to catch the attention of females. The phenomenon takes the form of males swimming in front of female fish and flaring out their fins while shimmying. If you see a fish doing this kind of behavior, you have strong confirmation that he is a male and his immediate audience is a female.
- Jochen Sands/Digital Vision/Getty Images


Nigeria table of contents like so many other modern african states, nigeria is the creation of european imperialism its very name--after the great niger river, the country's dominating physical feature--was suggested in the 1890s by british journalist flora shaw, who later became the wife of colonial governor frederick lugard. Imperialism is a state policy, practice, or advocacy of extending power and dominion, especially by direct territorial acquisition or by gaining political and economic control of other areas. The growth of the british empire was due in large part to the ongoing competition for resources and markets which existed over a period of centuries between england and her continental rivals, spain, france, and holland. Modern japanese history can be divided into four periods: 1600-1868: the period of the tokugawa shôguns feudal political order with economic and social change occurring in a gradual manner this period saw growing urbanization, the spread of popular education and the rise of the merchant class. The application of ideas about evolution and survival of the fittest to human societies - particularly as a justification for their imperialist expansion.
American imperialism is a term that refers to the economic, military, and cultural influence of the united states on other countries first popularized during the presidency of james k polk, the concept of an american empire was made a reality throughout the latter half of the 1800s. X the place of imperialism in history we have seen that in its economic essence imperialism is monopoly capitalism this in itself determines its place in history, for monopoly that grows out of the soil of free competition, and precisely out of free competition, is the transition from the capitalist system to a higher socio-economic order. Imperialism 101 chapter 1 of against empire by michael parenti imperialism has been the most powerful force in world history over the last four or five centuries, carving up whole continents while oppressing indigenous peoples and obliterating entire civilizations.
This is important because the british raj was a very significant ruling system of india lkdjlkgj also, the east india company, a major company at the time, collapsed because of the enfield rifles that they produced. And, remarkably, in the modern era, england, a small island nation on the periphery of eurasia, came to rule over the most impressive empire of all the fact that england became a dominant world power through its rule of the british empire, the largest empire in the history of the world, baffles us even today. The official web site of the canal authority provides a detailed history of the controversial panama canal from the early days of the french construction period, to its completion by the united states, and into the present.
1854: ostend manifesto issued by us ministers to europe the ministers write up a document that urges the us to annex cuba for the security of slavery, and that if spain refuses to sell the island, it should be taken by force. The scramble for africa is the general label for the period of european colonialism in africa in the late 19th century in 1885, fourteen european powers got together in berlin and literally took out a map and drew a bunch of lines and carved up the continent of africa. Empire's twin spans space, time, and the disciplines to craft a breathtaking new approach to an underexplored area of us history moving from the revolutionary era to the 1980s, it documents anti-imperialism in us history and depicts it as a tradition with a long, complex, and surprising history. Study 23 chapter 25: asia in the era of imperialism, 1800-1914 flashcards from aimee n on studyblue chapter 25: asia in the era of imperialism, 1800-1914 - ap history with kemp at john hersey high school - studyblue. When studying the history of countries across the world, the reasons behind the take over, and the general idea and practices involved in imperialism, there are always two sides to take into consideration (those sides being the imperial country and that which was.
American imperialism timeline unit 3 key terms-gilded age & progressive era age of discovery oman history ete computacion. American imperialism questions for your custom printable tests and worksheets in a hurry browse our pre-made printable worksheets library with a variety of activities and quizzes for all k-12 levels. Case studies analyze the history and influence of anarchism and syndicalism in colonial and postcolonial contexts (and thus within the larger context of late 19th and early 20th century imperialism and globalization) from the 1870s to the 1930s.
Sierra leone is a very rich country in diamonds and bloodshed the reason for the protracted civil war tearing sierra leone apart is the legacy of british colonialism and the struggle by the ruling cliques to rob the country's wealth if you want to know the value of a diamond here you should take. Welcome to - the era of new imperialism - 10th grade world history throughout this unit of study we will analyze some of the dynamic global changes that occurred throughout the era of new imperialism, with an emphasis on perspectives from both the colonizing and colonized countries. American imperialism had a major effect on the world in this lesson, find out how a nation became a part of the us for almost 50 years and how one kingdom became a us state.
Imperialism in ancient times is clear in the history of china and in the history of western asia and the mediterranean—an unending succession of empires the tyrannical empire of the assyrians was replaced (6th-4th century bce ) by that of the persians, in strong contrast to the assyrian in its liberal treatment of subjected peoples. A summary of imperialism in asia (1830-1900) in 's europe 1871-1914 learn exactly what happened in this chapter, scene, or section of europe 1871-1914 and what it means perfect for acing essays, tests, and quizzes, as well as for writing lesson plans. Start studying history unit 8 the era of imperialism learn vocabulary, terms, and more with flashcards, games, and other study tools.


Setting Up Your New Bird Feeder
Need to know what to do with that new bird feeder you just received? Follow these guidelines to keep your neighborhood birds interested and healthy.
To attract the right birds for your area, it's important to understand the type of feeder you have. Take a look at the box your feeder came in and match the correct type of seed, whether it be thistle, sunflower seeds, or peanuts to it for best results.
Feeder placement is also a critical aspect of successful bird stewardship. When placing a new feeder it's not unusual for birds to take up to two weeks to locate it. If you are having problems getting birds to your existing feeder and keeping them coming, consider the following common issues:
- If you're using a free-standing or hanging feeder away from the house, most birds will like a sense of enclosure that can be provided by a planting of shrubs or backing by a wooded area.
- The habitat should not provide cover for or be easily accessible to bird predators such as household cats or close to nesting or roosting areas for birds of prey.
- Be sure to use fresh seed. Since bird seed is a natural product high in oils it can often spoil if not kept in an air tight container or kept at an improper temperature. Ideally keep seed in a cool dry place, and remember that seed can spoil at different rates depending on the season.


My family is full of powerful and strong women. They’ve taught me so much over the years and have helped me to become the woman I am today. When I became a parent, I was excited to teach my child the same lessons my single mother, aunts, and grandma taught me. Then I found out I was having a boy. Over the next few years, I added two more little boys to the mix.
I started asking myself how I could teach them the same lessons and it hit me. Boys can learn just as much from strong women, if not more. It not only teaches them how to be better people, but inspired them with true stories, reminds them that women can do anything, and teaches them to respect women and their achievements.
Women’s History Month is the perfect opportunity to teach boys about strong women. While the month is focused on women and young girls, that doesn’t mean the boys should be ignored.
Influential women in history can teach our boys more than we think. Here are three reasons why boys should be celebrating Women’s History Month, too.
3 Reasons Boys Should Be Celebrating Women’s History Month
1. Inspired Boys With True Stories
Throughout history, women have taken courageous steps to defy society’s expectations.
Sarla Thakral was the first female East Indian pilot. At 21 years old, she was the first Indian women to fly a plane! She paved the way for other women to become pilots as well.
Mildred Loving stood up for love and because of her and her husband, Virginia stopped the ban on interracial marriage.
Harriet Tubman risked her life to help slaves get to freedom in the North.
Helen Keller defied all odds. She was deaf and blind, but learned how to communicate, graduated college, and fought for others with physical handicaps.
There are so many women in history that there is always a new story to learn. Find a story they haven’t heard before and let them get inspired. Let them see how one woman’s choices have changed their own lives.
2. Reminds Boys Women Can Do Anything
Society gives us the impression that men are better than women. By teaching boys about courageous women throughout time they see that the only thing that can stop a woman is her own fear. Women can do anything they set their minds to.
Most of the women our boys will learn about this month were told at some point in their lives that they couldn’t do it. They kept moving forward anyways and now the whole world knows who they are.
3. Teaches Boys To Respect Women
After boys have learned about real life, heroic women they start to appreciate them more. They realize what women have gone through to have the same rights as men, courageous moments they’ve had in history, and how they’ve helped to change the world. As their appreciation grows, it turns into respect. Their appreciation makes them want to treat women better and to help fight for a better world for men and women.
What do you think boys should be celebrating Women’s History Month?by
Latest posts by Brittany (see all)
- Celebrating Easter Around The World - March 12, 2018
- Teaching Our Kids It’s Okay To Stand Out At School - September 8, 2017
- Why Boys Should Be Celebrating Women’s History Month - March 22, 2017


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Great picture books to get kids interested in gardening
Want to instill a love of gardening in little children? Here are some fun, colorful picture books to get kids interested.
I have a new granddaughter arriving soon. That much-anticipated event and early signs of spring have me summoning up my earlier career as a librarian. It’s time to get this baby’s bookcase filled – with books about the garden, of course.Skip to next paragraph
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There are many fine picture books for young children – see list that follows – but I’m starting with my two favorites: Barbara Cooney’s "Miss Rumphius" and Peter Brown's "The Curious Garden." In addition to the authors also being the illustrators, the books have a similar theme: gardens make the world better.
Ms. Cooney, who died in 2000, is among the most celebrated American children’s book author-illustrators and the winner of two Caldecott Medals, the annual prize given for the “most distinguished American picture book.” "Miss Rumphius" won the National Book Award in 1983.
Calling the story one of “the closest to her heart,” Cooney writes of a little girl who sets three goals for when she grows up: to visit faraway places, to come home and live by the sea, and to do something to make the world more beautiful.
She eventually fulfills all three goals, but it is the third, making the world more beautiful, that is the most difficult. Until, that is, she discovers that the wind has spread the seeds of her lupines and decides to help nature by sowing lupine seeds wherever she walks until there are so many blooms that she becomes known as the Lupine Lady.
It’s a warm, charming story, gloriously illustrated in acrylic and color pencil. A classic.
Peter Brown, with four picture books under his belt, promises to have a notable career. "The Curious Garden" is a fictional account of the wonderful new garden – High Line Park – that has been created on an abandoned elevated railway over lower Manhattan.
In Brown’s version, a curious young boy named Liam discovers struggling plants on a rail bed and decides to help them grow. In time, the plants take on a life of their own, spread throughout the city, and transform it from gray to green.
And new gardeners pop up as well as new plants. Like the Lupine Lady, Liam not only makes the world more beautiful, he illustrates what a difference one gardener can make. Lively illustrations done in acrylic and gouache. A new classic.
If you’re looking to fill a bookcase, consider the following titles, all picture books written for young children. Many are available in paperback and as board books as well as in hardcover. (And if you have favorite books to interest kids in gardening, do mention them in a comment below.)


Death is but a natural phenomenon. And following the death of an individual, it is important to cremate or dispose of the body properly. But if you do not follow this, it could lead to many severe consequences.
That’s what funeral homes are actually for.
And though you cannot call the bodies of your loved ones a ‘waste’, the fact is that all kinds of funeral homes generate some amount of wastes and these can be hazardous in nature.
No wonder, all these funeral homes too need the assistance of biohazardous waste disposal agencies to manage their generated waste.
Here are some important points which you need to know relating the funeral home medical wastes and how these funeral homes get assistance:
- The Major Funeral Methods
- Types of Funeral Home Wastes
- OSHA Regulations & Funeral Homes
- Segmenting Funeral Home Wastes
- How To Ensure Safety
Let us know and understand all these points in a bit detail:
- Major Funeral Methods:
In the USA, the most common form of body disposal is burial, and cremation follows it swiftly.
While burial is an absolutely simple process, cremation actually takes a lot of essential elements into consideration. In this, the body enters a disposal chamber in a container with a garment, and it gets subjected to natural gas which heats the same.
The exhaust gases and smoke are not allowed to pass out and enter a scrubber where they get absorbed.
If the body contains any artificial devices such as pacemakers etc., these are removed in advance. And without any doubts, all such blood-smeared products contribute to biohazardous wastes.
In addition, the residue left after the cremation of a body ranges anywhere from 3 to 6 pounds which need to be disposed of effectively.
- Types of Funeral Home Wastes:
When we talk about funeral homes, we may roughly include cemeteries, morgues, and mortuaries etc.
No wonder, funeral homes too generate a considerable amount of waste and these are varied in nature. For instance, some of the major types of medical wastes that emerge out of the funeral home are as follows:
- Dressings, swabs, and other fabrics
- Incision needles
- Arterial tubes
- Phenol etc.
And broadly, these wastes can be grouped under categories such as:
- Chemical Wastes
- Sharps wastes
- Pharmaceutical Wastes
- Radioactive Wastes
- Chemotherapy wastes etc.
- OSHA Regulations & Funeral Homes:
The OSHA or ‘Occupational Safety and Health Administration’ is an agency that provides healthcare training and clearly states the ways to mitigate hazardous wastes.
According to OSHA, all the employees which are directly or indirectly subjected to bloodborne pathogens or infectious body fluids must possess proper OSHA training. This encompasses outlining all the exposure control plans and ways to stay protected from the infectious wastes.
You can get the best OSHA training assistance from a reputed medical waste disposal agency in your region which would also help you deal with all kinds of generated medical wastes.
- Segmenting Funeral Home Wastes:
As aforementioned, funeral homes generate various types of wastes and not each of them could be added to a single container.
Therefore, as stated above, you need to have separate waste disposal container for each of these and in this too, a good and licensed medical waste management agency can offer great assistance.
Also Read: Why Medical Waste Disposal Is Required?
For instance, if the funeral homes discard sharps wastes, it is important to store them properly in dedicated sharps containers so that they do not cause any harm to the living beings that come in contact with them.
- How To Ensure Safety:
As informed on every step, funeral homes can get the best assistance from a good medical waste disposal agency such as ‘Secure Waste Inc.’
All such agencies offer ‘A to Z’ assistance in terms of generated medical wastes and prevent any form of troubles which arise due to negligently discarded funeral home wastes.
Key Takeaways From Above:
Here are the major points that we learned from all that we mentioned above:
- Funeral wastes are not at all simple and could be hazardous in nature. Thus, you need an expert medical waste management agency to take care of these.
- Funeral homes could be varied in nature and they discard various kinds of wastes.
- It is important to identify & segregate every kind of waste generated and store it properly in the designated container.
- You can get every assistance that you need from a reputed medical waste management agency.
- All such medical waste agencies provide waste storage containers, waste-disposal documents, and are responsible for every action right from picking up the filled containers to disposing of them safely.
- Funeral homes too are governed by OSHA regulations and the employees at such places must be provided proper OSHA training for the best outcomes.
- People who handle hazardous wastes emerging from the funeral homes must use personal protective equipment (PPE) to stay protected from any form of medical troubles.
So if you are concerned with a funeral home, ensure to consult a good medical waste management agency such as ‘Secure Waste Inc.’ and you can ensure to stay away from all the medical and legal hazardous waste troubles.


There's hope and help for overweight kids
Dealing with kids' weight is one of the most delicate dances of parenthood.
We want to make sure our children are well nourished and have a healthy, positive relationship with food. We don't want to damage their self-esteem by calling undue attention to their weight (whether they're thin or chubby), and we don't want to alienate them by constantly reminding them to slow down on snacks and get their butts off the couch. When your child is overweight, it's hard to find words to voice your concerns, words that won't push the child toward even worse eating and exercise habits, and away from you.
Finding a way to help kids deal with their excess weight has never been so crucial. The federal National Health and Nutrition Examination Survey estimates that about a third of all children and teens are overweight; 16 percent are obese. Recent research has connected being obese as a teenage girl with dramatically increased risk of developing multiple sclerosis as an adult. Obese teen girls, also according to recent research, are more likely to suffer infertility as adults. Overweight teens of both sexes are at increased risk of Type 2 diabetes, a disease once reserved for older adults. And overweight adolescents too often turn into overweight adults. Though some experts may dispute that being overweight translates to ill health, numerous studies have shown associations between being overweight and such conditions as cardiovascular disease and many cancers.
Sometimes it seems the world has conspired to make our kids fat. Ads for highly sweetened, fat-laden treats bombard them through television and computer screens. In many communities, playing outside and walking or biking to and from school is no longer the norm. Physical education has been squeezed out of schools, where the food served at lunch is often a nutritional disappointment.
If all that sounds dire, though, rising public awareness of childhood obesity as a major threat to our nation's future health has led to new initiatives to address the issue. The American Academy of Pediatrics, for instance, offers a Web site, http:/
Kim Perry, the program's director, says, "It's a movement of young people who believe in prevention, in eating right and moving around more." EmpowerME's online offerings are focused on two age groups: 8-to-12-year-olds are the prime target, with 13-to-17-year-olds treated as "influencers" whose behaviors set examples for the younger set.
The program encourages kids to get 60 minutes of physical activity every day (not necessarily all at once, Perry notes); to make water, milk and 100 percent fruit juices their primary beverages; to eat fruit or vegetables at every meal; to limit total screen time (watching TV, using the computer or playing video games) to one to two hours a day; and to get nine hours of sleep every night. The Web site offers tons of tips and tools for meeting those goals.
Eventually, participants learn how to become advocates in their homes, schools and communities, looking for ways to increase access to healthful food and make outdoor play safe and available.
Dawson MacKay of Bethesda had already lost weight by the time he joined EmpowerME.
"I was a little overweight in third grade," he says. "My parents are both doctors, and they informed me. They tried to be nice to me. They told me I was overweight and that that wasn't good, so I should try to eat better and eat less and start exercising more."
Dawson says he took their advice in stride. "They talk to me a lot about health, and they're usually right," he says. Losing weight "wasn't too hard," he says, "but I had to get out of my regular routine."
Today 10-year-old Dawson, now in fifth grade, eats an admirably healthful diet, plays several sports and rides his bike to school, where he's working to improve the nutritional quality of school lunches. Though he takes his own lunch (ham or turkey with cheese and lettuce, two pieces of fruit and some Goldfish or Cheddar Bunny crackers), he's concerned about what he sees served in the cafeteria.
"Today," Dawson reports, "it was fish-and-cheese nuggets, french fries and chocolate pudding." As if that weren't bad enough, Dawson adds, "Some kids go back and get a second lunch."


The Surprising Health Benefits of Eating Weeds
Ask any gardener what the most overwhelming part of their job is, and they’ll probably tell you “weeding.” It’s a necessary evil – and yet, some people find the action of ripping plants from the ground to be surprisingly therapeutic. But if you’ve ever walked out into the yard and recoiled in horror at the sight of unwelcome horticultural guests, you know how stressful it can be.
Instead of working against weeds, why not work with them to make your garden the best it can be? “But that makes no sense,” you say, “that clover is choking out my lawn!” While it’s true that every space needs some thinning to ensure that your plants get the nutrients they need to grow, weeds play an important role in the garden, from breaking up compacted dirt to providing a barometer of the soil from which they sprout (they also give you a hint at what type of soil you have– knowledge that’s absolutely essential in ensuring optimal germination and growth).
Though they vary in species from region to region, “weeds” spent hundreds of millions of years learning to adapt to weather, predators, humans, you name it. As a result, most of them have developed defense mechanisms to ensure their survival. Some, like the ubiquitous dandelion, have deep taproots that reach into the soil to mine minerals and moisture that young plants may not be able to reach. These “deep divers” also create breathing room in crowded soil, giving roots of vegetable plants more room to “eat,” so to speak.
She notes that watermelons and onions from the weediest part of the patch grow to be larger or better tasting than those from better groomed areas, and some farmers even plant weeds like Jimsonweed to boost the vitality of their pumpkin patch.
Exhausted 9-to-5ers, take note: certain vegetables can actually benefit from a laxer approach to weeding! In her essential book, Carrots Love Tomatoes, Louise Riotte mentions several common weed-plant partnership. She notes that watermelons and onions from the weediest part of the patch grow to be larger or better tasting than those from better groomed areas, and some farmers even plant weeds like Jimsonweed to boost the vitality of their pumpkin patch.
Weeds tend to proliferate wherever conditions are favorable, but every plant (and weed) has a preferred soil type (or types). If all you see in a patch of dirt is stinging nettle and quack grass, you might have heavy clay soil-– not easy to work with, but favorable for asters and Japanese irises. Other weeds serve as indicators that you’re doing something right, and you’re working with fertile land; if nothing but lambs-quarters and horehound are populating your yard, it’s a good sign. Taking the time to learn and identify common weeds is a bit like being a detective; careful observation is key. [Editor’s Note: We’ll be running a story on edible weeds in the future– stay tuned!]
All plants are nutrient sinks, so let your weeds die out in the fall. Come spring, those nutrients will feed another generation and keep the garden going. You can also make a liquid fertilizer or “weed tea” for a bigger boost (no, you won’t get stoned).
And so, I speak in defense of the much-maligned weeds, Mother Earth’s ruthless freeloaders. They may suck and they may be ugly, but by working with them carefully and confidently, even a gardener’s worse weeds tend to redeem themselves– if only a little. So don’t stress out. A little competition is a good thing.


Embedded systems means different things to different people, anywhere from 8-bit micros that cost less than a dollar and have only a few KB of Flash and a couple of hundred bytes of RAM, to ARM-based boards with a GB of Flash and MBs of RAM running a platform like Android. Since you already have an Arduino, I assume you are talking about smaller systems.
In order to be successful in the embedded systems field, it is very useful to have some background in electronics. You will often be writing code to interface with the various peripherals (serial busses like UART, SPI, I2C or USB), 8 and 16-bit timers, clock generators, and ADCs and DACs. Although I have not programmed on one, my understanding is the Arduino platform isolates you from most of this by providing canned routines to access the various peripherals on the board. In the real world, you probably won't have this luxury.
"Datasheets" for microcontrollers often run into the hundreds of pages as they describe every bit of every register. If you haven't done so already, you should download the datasheet for the ATmega32 microcontroller in your Arduino Uno.
It also helps to be able to read a schematic so you can probe a board with an oscilloscope or logic analyzer. If you have no background in electronics, but are still interested in getting "down to the metal", then I highly suggest taking some introductory courses in electronics. It is also essential that you know C, as most microcontroller firmware is programmed in that language. You already have a head start there, as the Arduinos provide a simplified version of C/C++ functions.
It would also be a good idea to work with a 32-bit microcontroller, as the embedded market is quickly moving to these as their price has come down to where the 8-bitters used to be. I happen to like the PIC32 series from Microchip. You can get a complete development board from SparkFun for $40. You don't need to buy anything else to start with, since there is a bootloader built-in. You can also use one of Microchip's programmers like the PICKit 3.
This board uses the PIC32MX795, which has 512K flash and 128K of RAM, which is a lot more than you are used to on the Arduino. There are tons of free libraries to make programming the peripherals easier, but you will still need to read the PIC32 datasheet to understand how to use them.
Microchip has a free IDE and compiler that runs on Windows, Linux, and Macs. (They also have a paid version, but all that gives you is optimizations to produce smaller code. You don't need that for hobbyist use.)


As the cannabis industry continues to expand, new terminology and products are popping up left and right, making it overwhelming for both cannabis newbies and connoisseurs alike. Two terms that have gained popularity in recent years are "hemp flower" and "hemp biomass." While both are derived from the same plant, they are vastly different in terms of their appearance, composition, and usage. In this blog, we'll explore the differences between hemp flower and hemp biomass, and help you understand which product may be best suited for your needs.
What is Hemp?
Hemp is a variety of the Cannabis sativa plant species. Unlike marijuana, which is another variety of Cannabis sativa, hemp contains very low levels of tetrahydrocannabinol (THC), the psychoactive compound that produces the "high" associated with marijuana use. Hemp has been used for a wide range of industrial and commercial purposes for thousands of years, including the production of textiles, paper, biofuels, construction materials, food products, and supplements. In recent years, hemp has gained attention for its potential health benefits, particularly through the use of CBD, a non-psychoactive compound found in hemp that is believed to have therapeutic properties.
What is Biomass?
Biomass refers to the organic material derived from living or recently living organisms, such as plants, animals, and microorganisms. It can be used as a renewable energy source, as it contains stored energy from the sun that can be released through combustion or other chemical processes. Biomass can include a wide range of materials, such as wood chips, agricultural waste, algae, and even municipal solid waste. It can be processed and converted into various forms of fuel, such as pellets, liquid biofuels, or biogas, which can be used to generate electricity, heat, or power vehicles. The use of biomass as a fuel source is seen as a way to reduce dependence on fossil fuels and mitigate climate change by reducing greenhouse gas emissions.
Hemp flower, also known as CBD flower, refers to the flowering buds of the female hemp plant. These buds contain high concentrations of cannabidiol (CBD) and other cannabinoids, but very low levels of THC. Hemp flower is typically harvested by hand, dried, and then trimmed to remove the stems and leaves.
It can be consumed in a variety of ways, including smoking, vaping, or brewing as a tea. Many people prefer using hemp flower as a natural and holistic way to consume CBD and other cannabinoids, as it is minimally processed and contains a range of beneficial compounds that work together to produce what is known as the "entourage effect."
Hemp biomass refers to the organic material derived from the hemp plant, specifically the stalks, leaves, and other plant matter that remains after the flowers and seeds have been harvested. Hemp biomass is a valuable resource in the production of a wide range of hemp-derived products, including CBD oil, textiles, paper, and building materials, as well as biofuels and other industrial products.
Because hemp biomass is high in cellulose, it can be processed into a variety of useful forms, such as pulp, pellets, or fibers, making it a versatile and sustainable raw material. Additionally, because hemp biomass is grown using sustainable agricultural practices, it is considered to be a highly eco-friendly resource that has the potential to help mitigate climate change and reduce dependence on fossil fuels.
Honorable Mention: Industrial Hemp
Beyond hemp flower and hemp biomass there is a strain of hemp that is grown specifically for industrial uses. The honorable mention of industrial hemp is put forth to show how versatile and beneficial the hemp plant can be.
Industrial hemp has a wide range of uses, including the production of fiber for textiles and paper, seed for food and animal feed, and oil for cosmetic and health products. It can also be used for the extraction of CBD and other cannabinoids, which are used in various health and wellness products.
Compared to other crops, industrial hemp is relatively easy to grow and requires less water and pesticides. It also has a short growing cycle of around 90 to 120 days and can be grown in a variety of climates and soil types.
Are Hemp and Hemp Biomass Legal?
The legality of hemp flower and hemp biomass in the US depends on their THC content. Hemp is defined as cannabis with no more than 0.3% THC on a dry weight basis, according to the Agricultural Improvement Act of 2018 (also known as the 2018 Farm Bill).
If hemp flower and hemp biomass contain THC levels that are below the legal threshold of 0.3%, they are generally considered legal under federal law. However, it is important to note that some states have implemented their own regulations regarding the production and sale of hemp products, so it is advisable to check the specific laws in your state.
Can you Smoke Hemp Biomass?
While it is technically possible to smoke hemp biomass, it is not typically recommended or used for that purpose. This material is typically lower in cannabinoid content, including CBD, than the hemp flower, and can be harsh and unpleasant to smoke. Moreover, smoking hemp biomass can potentially release harmful toxins and chemicals that can damage the lungs and respiratory system.
Instead, if you're interested in smoking hemp, it is generally recommended to use high-quality hemp flower, which is specifically bred for its desirable cannabinoid and terpene profile, and is generally considered to be more enjoyable and effective for smoking.
Elaboration: Ways to Consume Hemp Flower
While hemp biomass should not be consumed, there are multiple ways to consume and benefit from hemp flower. Consumers can find CBD in topicals, tinctures, edibles, and a multitude of other products. However, the most effective way to consume CBD hemp flower is through inhaling it.
The science behind the effectiveness of inhalation has to do with the bioavailability and biodelivery available in the consumption method. By inhaling CBD vapor the molecules are able to quickly enter the bloodstream and begin to work with the body.
Hearing inhalation is the most effective way to consume hemp may have users ready to pack a big bowl of CBD flower, but this is not the best option. Traditional smoking methods use combustion to burn the flower, which exposes users to toxins and carcinogens in the smoke produced.
Instead consumers should look for a dry herb vaporizer that uses heat-not-burn technology to heat the flower to an optimal temperature that will not not produce the toxins associated with traditional smoking. The elon® by E1011 Labs is a high-quality dry herb device that pairs with flower pods prefilled and predosed with CBD-rich flower. Using the elon® allows consumers to get their daily dose, or doses, of CBD in a convenient and user friendly way.
Flower vs Biomass
In summary, while hemp flower and hemp biomass are both derived from the hemp plant and contain beneficial cannabinoids, they are used for different purposes and have distinct characteristics. Hemp flower is typically used for direct consumption, with smoking and vaping being popular methods, while hemp biomass is commonly used for industrial purposes, like biofuels and textiles.
Whether you're a cannabis newbie or a seasoned connoisseur, understanding the differences between hemp flower and hemp biomass can help you make an informed decision on hemp products to buy, both consumable and non-consumable.


Staff of the Federal Writers' Project. Courtesy of the National Archives.
During the darkest days of the Great Depression, artist Alice Neel painted a surreal portrait of her friend, the poet Kenneth Fearing. In it, the gaunt 33-year-old stares out through owl-rimmed glasses, eye sockets hollow from exhaustion and hunger, a gaping hole in his chest. There, a grinning skeleton perches, spilling a river of blood.
These were dark times. And Fearing was the poet for them.
Eighty years ago he burst onto the literary scene with his reckless and stylized first book, Angel Arms. The strongest pieces were free-form riffs on hard-boiled fiction themes: “dangerous, handsome, cross-eye’d Louie the rat / Spoke with his gat, Rat-a-tat-tat—” snarled “St. Agnes’ Eve.” A majestic revolutionary spirit balanced beside these staccato pieces, like this stanza from “Ballad of the Salvation Army”:
On Fourteenth street the bugles blow,
Bugles blow, bugles blow,
The torpid stones and pavements wake,
A million men and street-cars quake
In time with angel breasts that shake,
Blow, bugles, blow!
Though the poems were written earlier, during the Roaring Twenties, Fearing’s apocalyptic imagery proved timely. Coward McCann published Angel Arms in 1929, within months of the stock market crash that plunged the United States into the Great Depression. Historian Monty Noam Penkower details the meltdown’s subsequent catastrophic effect on the literary scene in The Federal Writers’ Project, stating that between 1930 and 1933, new books published decreased from 10,000 to barely 7,600, magazine advertising dropped 30 percent, and newspaper “mortality rates” reached 48 percent (sound familiar?).
In this climate, Angel Arms barely registered in the critical press, and Fearing churned out pulp fiction and porn to keep afloat. His first wife, Rachel Meltzer, told scholar Robert M. Ryley that “his shirts . . . were green with grime, his teeth covered with tartar.” She held down the household’s only steady paycheck, working while her husband wrote. Ryley noted that “she would get so tired that, much to Fearing’s annoyance, she would fall asleep at parties.”
Albert Halper’s 1933 novel Union Square parodies the poet as a drunken wreck: “‘Blow, bugles, blow,’ he mumbled sloppily, ‘and answer, hot dogs, answer, wharking, jarking, karking. On Fourteenth Street the mustard’s green, in Union Square the mob is queen. Blow, bugles, blow, set the wild echos barking. And answer, comrades, answer, harking, larking, farking.’” Alongside Neel’s portrait, these two works present the Fearing of that time as a troubled—and troubling—genius.
He seemed headed for oblivion, but the Federal Writers’ Project (FWP)—a government-funded program that lasted from 1935 until early 1943, employing thousands of writers around the country as oral historians, researchers, and authors of state guidebooks—rescued him, if only for a short time. For some writers, like Claude McKay and May Swenson, the FWP provided a foundation from which they could launch their later careers after the economy picked up. For others, like Fearing, the project provided a brief respite from what came to seem an inevitable decline. But in that brief time, the FWP enabled Fearing to write some of his most enduring works.
As his poetic output lagged during the pre-FWP days of the Great Depression, Fearing found solace in New Masses, a weekly labor bugle. Running from 1926 until 1948, the radical magazine published some of the most famous voices to emerge from the Great Depression, including Upton Sinclair, Richard Wright, and Langston Hughes. In the early 1930s, Orrick Johns—a scrappy poet who had lost a limb in a childhood accident and who navigated the Greenwich Village literary scene on one wooden leg—edited the poetry section. By his own estimate, Johns read 400 poems every month for the magazine. In the mid-1930s, New Masses averaged about one poem a week. Despite these daunting odds, Fearing was a valued contributor, publishing more than 30 pieces there. During Johns’s tenure, Fearing published five poems—despite the critical disinterest in his first book.
In the summer of 1935, more layoffs and closings rocked the literary world, and Johns lost his New Masses job. The editor didn’t stay unemployed for long, landing a directorship at the newly formed FWP in New York City. Housed in the cavernous Works Progress Administration building at the Port Authority, the FWP opened in 1935. At its peak, this bureaucratic beehive paid more than 600 writers around $20 a week (about $300 today) to collect information, write guidebooks, and record folk histories, among other projects. Nationwide, the FWP employed around 6,600 writers—among them Lorine Niedecker and Conrad Aiken, Zora Neale Hurston and Studs Terkel, John Cheever and Saul Bellow.
Johns was tasked with picking writers from a demoralized talent pool in New York City. “They were all from the home relief rolls, and it took weeks for some of them to get the habit of clean shirts and pressed trousers. They ran the gamut of mental states, the scared and the stolid, the humble and proud, reserved and excitable, with a scattering of plain drunks.” He selected many New Masses writers for the project, including Fearing.
Fearing thrived as an FWP staffer, uniting the fractious collection of authors and radicals in the project. According to Jerre Mangione, the FWP’s coordinating editor, Fearing “was one of the project’s most popular staff members and had friends in all camps.” Early in his career, Fearing was pigeonholed as a “proletarian poet,” but avoided taking sides in political debates (something that probably helped at the FWP). When FBI agents asked if he was a Communist, the poet replied: “Not yet.” For years scholars have debated his true ideological stance during these difficult days.
In 1935 Fearing published his second collection, Poems. Out of the 20 pieces in the slim volume, eight were first published in New Masses. This new work blasted the bankers, fat cats, and politicians who had plunged the country into an economic dark age. Straight from the pages of New Masses, the bombastic “Dirge” dishes out comic-book retribution. “Wham, Mr. Roosevelt; pow, Sears Roebuck; awk, big / dipper; bop, summer rain; / Bong, Mr., bong, Mr., bong, Mr., bong.” The pop hymn mocks and mourns the domesticity of J. Alfred Prufrock in Fearing’s most famous poem:
And wow he died as wow he lived,
going whop to the office and blooie home to sleep
and biff got married and bam had children and
oof got fired,
zowie did he live and zowie did he die
The country’s resentment over the economic meltdown electrified the poet’s experiments. Horace Gregory summed it up in his 1946 anthology, A History of American Poetry, 1900-1940: “When his second book, Poems, appeared, the public that had ignored Fearing suddenly discovered his value . . . a generation that was more distinctly urban, that was self-consciously ‘hard-boiled,’ that had shared the hopes and disillusionments of 14th Street in New York and Union Square.”
The populist anger that Fearing kindled resembles 21st-century rage over CEO bonuses and stock market scammers, though no poet today has yet claimed this zeitgeist in the way Fearing captured his. The first print run of Poems quickly sold out, becoming a surprise hit despite the Depression. His success shocked the New York Times books section, earning his publisher headlines for “unusual sale of their volumes of radical verse.”
As a fellow Greenwich Village bohemian, Orrick Johns had radical dreams for the FWP. He imagined revolutionizing the writing economy and unionizing the profession. Inside the WPA bureaucracy, he struggled to realize “the hopes and disillusionments of 14th Street” that Fearing expressed. However, Johns couldn’t tame the hungry, desperate masses. He lasted barely a year and a half of the tumultuous program. Hunger strikes, brawls, scandals, and malfunction constantly threatened his hold on the organization. During one FWP hiring scandal, the New York Times reported a particularly violent protest outside the Emergency Relief Bureau headquarters. The New York Fire Department arrived at the mob of nearly 3,500 disenchanted workers and spectators with a “newly equipped sound-truck used to broadcast police instruction among the huge crowd.”
By 1936 Johns was making headlines on a monthly basis, struggling to control his public image and the image of the FWP. “The total volume to date [published by the FWP], more than 8,000,000 words, dwarfs the combined wordage of the three ‘jumbo’ novels of the day . . . plus all of Shakespeare and the King James version of the Bible,” he boasted to the New York Times in September, countering the nearly daily reports of Communist infiltration and productivity problems.
After an all-night party in October 1936, one rejected FWP applicant attacked Johns, beating him senseless, drenching him with booze, and lighting him on fire. “When I woke up,” he wrote, “some of my teeth were scattered on the floor and blue flames were rising around my face.” It took him six weeks to recover, and he resigned his FWP post at the end of the year. He fled to Connecticut, drinking and writing a memoir. He would never publish poetry again. The Times reported his 1946 suicide: “drinking a poison concoction he mixed in a glass of beer.”
As Johns declined at the end of the Depression, Fearing reached the pinnacle of his poetic career: praised as an exemplary FWP member, earning Guggenheim Fellowships, and landing a contract with Random House. Sadly, it wouldn’t last. In 1938 he published the poetry collection Dead Reckoning. “[He] was content to repeat the earlier successes of his writing with slight variations on a central theme,” wrote Horace Gregory.
The collection includes “Literary,” a sarcastic advertisement from an imaginary writing school brochure. Fearing rails against “The Literary System” that provides
[a] thousand noble answers to a thousand empty
questions, by a patriot who needs the dough.
And so it goes.
Books are the key to magic portals. Knowledge is
power. Give the people light.
Writing must be such a nice profession.
Fill in the coupon. How do you know? Maybe you
can be a writer, too.
After his singular moment passed, Fearing’s verse would get buried among the “thousand empty questions” that concerned writers after the Great Depression. He found more fame as a novelist in the 1940s, writing a string of novels that climaxed in The Big Clock in 1946. Ray Milland starred in the classic film noir adaptation of the book, which eclipsed the fame Fearing’s poetry once enjoyed.
After his second marriage dissolved in 1952, Fearing spent the last years of his life in his bachelor apartment. He drank pints of whisky every day, cobbling together a living as a publicist, book reviewer, and, once again, pulp writer. The poet—without New Masses, Johns, or the particular battles of the Depression—lost the fight against the bloody skeleton lurking inside. He died in 1961.


English holly is a versatile, hardy plant combining year-round beauty and wildlife appeal. But when it escapes cultivation it can become an uninvited pest.
My first encounter with English holly (Ilex aquifolium) was making holiday decorations in elementary school. Nearly 20 years later, I encountered the plant again as a restoration volunteer with the City of Seattle working to remove invasive plants from parks and greenbelts. Himalayan and evergreen blackberry (Rubus sp.), English ivy (Hedera helix), and English holly were removed and replaced with native sword ferns (Polystichum munitum), salal (Galtheria shallon), and Oregon grape (Mahonia aquifolium).
When visiting my parent’s property in rural Grays Harbor County, I was surprised to find English holly among the second growth Douglas fir (Pseudotsuga menziesii) and Western red cedar (Thuja plicata) forest; these plants were volunteer offspring of an old tree planted on an adjacent property. Seeing the interlopers randomly scattered throughout the forest made me wonder why English holly grew in one area versus another. Since 2009, I have worked to answer that question for my Master’s thesis at the University of Washington’s School of Environmental and Forest Sciences.
English holly is an evergreen plant that can grow as a tree or sculpted into hedges to form a living fence. Its red berries provide a speckling of color in the dark green foliage and provide a valuable food source for birds who find refuge within the dense branches. A shade-tolerant understory in its native European deciduous forests, English holly grows equally well in sun or shade in the Pacific Northwest, where our mild climate provides ideal growing conditions.
Introduced in Oregon in 1874—possibly by a homesick Englishman or woman wanting to recreate a bit of the English countryside—a market developed for the plant’s foliage for holiday décor. Today more than 90 percent of the English holly sold in the United States is grown in the Pacific Northwest with the support of the Northwest Holly Growers Association. Washington farms alone generate $5 million annually, providing employment and tax revenue.
The very traits so prized by gardeners—hardiness, adaptability, and wildlife support—are the same qualities that make English holly a potential problem as birds distribute the seeds throughout parks and forests without respect for property lines. Once a seedling matures into a sapling, survival is almost guaranteed. If this sapling is a female, and if there is a male tree nearby to enable fertilization, more berries are produced and the cycle repeats itself. An extensive, deep root system enables the plant to withstand tough conditions. And like Western red cedar, English holly can sprout new shoots from branches lying on the ground, creating dense, difficult-to-eradicate thickets where it competes for space and nutrients to the detriment of native plant communities.
In 2010, King County submitted a proposal to the Noxious Weed Control board (NWCB) asking that English holly be designated a class C noxious weed so counties could educate citizens about the plant’s potential negative impact on the landscape. Steven Burke, speaking on behalf of King County, presented an Earthcorps survey of Seattle’s urban forests at an NWCB meeting. The survey reported that English holly occupies 320 stems per acre; in the City’s coniferous forests, English holly represents over 60 percent of all tree regeneration. From 2007 to 2009, Seattle Public Utilities spent nearly $90,000 to eradicate English holly at Lake Youngs. Arguments against the noxious weed classification were offered by people living around holly farms who did not find the plant to be invasive and holly farmers who maintained that they could control the plant with chainsaws.
After weighing public testimony, the board declined the designation based on a lack of scientific evidence about the plant’s impact on native areas and in protection of the commercial English holly market, which they felt would be economically damaged by a noxious weed classification. But this wasn’t the end of the English holly debate. In 2011, House Bill 1169 and its companion Senate Bill 5087 sought to amend the laws governing noxious weeds by stipulating that a plant “actively cultivated in Washington as a commercial crop” cannot be classified as a noxious weed. The legislation was revised with language stating that any listed plant must have scientific evidence to support its listing, and the legislation passed.
Debate over English holly has quieted for now, but the study of its effect on the landscape is ongoing. My research focuses upon whether stand characteristics such as tree spacing or volume can be used to predict English holly’s presence within a forest. Other researchers predict that English holly may eventually become the dominant understory species within City parks and forests, which could have long-term implications for the structure of Pacific Northwest forests.
So what’s a gardener to do? English holly is here to stay. Pacific Northwest natural resource managers are more concerned about its presence in natural areas such as state parks or national forests than in urban settings like backyards. Yet the story of English holly is a cautionary tale of the unexpected consequences of introduced plants. While some plants cannot survive without human assistance, others thrive, escaping cultivation. Even though English holly has lived in the Pacific Northwest for over 100 years, only now are we starting to see its effect on our forests and wild spaces. Which prompts the question: How many newly introduced plants will venture on the wind or be carried by a bird beyond the backyard to impact the native environment? And at what cost?


The Undiscovered Country
The statistics of death show leaps in modern life expectancy but fail to answer the question: Why do we die?
Needs a Ring Job, New Clutch
But for now let's leave aside the question of how long humans can live and concentrate instead on why most of us will not live to see the century mark. In 1990, the illustrious Russian biologist Zhores Medvedev sought to classify the more than 300 theories that had been put forth to account for this ineluctable reality. Many of these theories, compelling in their own right, likely capture some of the underpinnings of our mortality. Their sheer number, however, suggests as much about the complexity of the question as it does about the difficulty of thinking dispassionately about death. Scientists, after all, are people who are going to die too.
Theories of death are also deeply embedded in their culture of origin. Let's consider, for instance, the class of mechanical explanations of death. These hypotheses invite us to accept the metaphor of the human body as a machine with many parts that must work in concert. In this metaphor, we die either because a key component gives way (the catastrophic failure model) or because several interacting parts begin to wear out and no longer work properly (the systems failure model). These metaphors of failing machinery compel, but data supporting them are harder to obtain. Catastrophic failures, like heart attack and stroke, are major killers in the developed world, particularly in the United States. Many of these deaths, however, are preventable and linked to a sedentary lifestyle, and not to an inherent age-dependent failure of a particular organ system.
The systems-based explanation argues that complex machinery fails because many things go wrong. According to this model, as with your Toyota, so too with your body: The force-of-mortality curves for automobiles (called failure-rate curves) complied by demographers James W. Vaupel and Cynthia R. Owens at Duke University bear an uncanny resemblance to their human counterparts. Both human and automobile curves show an exponential increase in the force of mortality that tapers off in later years—the same violation of the Gompertz Law we spoke of earlier. Surprisingly, mortality in the early years is eerily similar in people and automobiles: Defects in manufacture (machines) or development (organisms) reveal themselves early on. But if you (or your car) make it past the first year, you're likely to motor along for a good period thereafter. The patterns are tantalizing in their similarity and may reveal some fundamental features of failure in complex systems. Such systems, whether we speak of Toyotas or biologists, are characterized by redundancy brought about by engineering (in the first case) or evolution (in the second). But, as University of Chicago gerontologists Leonid Gavrilov and Natalia Gavrilova have argued in their influential bookThe Biology of Life Span: A Quantitative Approach, the very redundancy that permits complex systems to endure a constant rain of light damage also allows such damage to accumulate, resulting in aging and eventual failure. Surprisingly, the higher the level of redundancy, the faster the force of mortality accelerates with age. The irony is that the redundant mechanisms that ensure survival during our early years are the same ones that speed our twilight exit.
For two centuries, biology has profited from Rene Descartes's conception of the human body as a machine, subject to, and more importantly, explainable by, material laws. Compelling as the Cartesian metaphor of the body-as-machine might be, it may, however, conceal some important differences between my automobile and me. Repair, for instance, is a process central to survival. I depend on my excellent mechanic, an agent external to my automobile, to keep my car on the road. In contrast, bodies, for the most part, repair themselves: More than 100 genes in our genome are devoted to detecting and repairing DNA damage.
This notion of the body as a self-policing, self-correcting system has spawned a second class of death explanations, those related to maintenance. Although the human body can detect and remedy a startling array of defects, this capacity to self-renew declines with age. Even the raw materials for repair—those stem cells recruited to replace exhausted counterparts—become depleted. The damage to our bodies, meanwhile, continues unabated throughout our lives. Much like the inventive mechanics in Cuba who keep Edsels and Cadillacs from the '50s running without spare parts, the body struggles to patch up broken functions as replacement cells decline. But it is, ultimately, a losing battle. In a final ironic twist, the repair process, like the existence of redundancies, becomes a source of trouble as we get older. The inflammation that accompanies injury and repair is itself a source of further damage. Aging and death may come about when we can no longer keep up with the maintenance required to stay alive.


عنوان مقاله [English]
نویسنده [English]چکیده [English]
Verse 84 of Surah Al-Isra represents most essential basis of human deeds in the word “Shakilah” (manner), where it says “Say, each works according to his manner …” There are only the two words of “Shikl” (form) and “Shakilah” (manner) from the root word of “Sha-ka-la” in the Holy Quran, while the majority of commentators and lexicographers offer quite different definitions for the word “Shakilah”. Of course, some definitions are figurative. Lexicographers’ attempts to find a collective meaning for the root word of “Sha-ka-la” have yielded no results thus far. Some lexicographers have presented “likeness” as a synonym for the Arabic root word, but it is not that much accurate. This paper intends to apply semantics and resort to etymological studies to explore semantic components of the root word of “Sha-ka-la” in early Arabic languages to find how these components have established links with the concept of “Shakilah” in Arabic language. In the light of this method, we have indicated how intrinsic and extrinsic semantic components in the root word of “Sha-ka-la” have found their way from the early Arabic languages to the contemporary Arabic language and how they affected the meaning of “Shakilah”.


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Mature lymphocytes are white blood cells that travel through the lymphatic system and help humans and animals fight diseases. All mature lymphocytes are either T cells or B cells. T cell lymphocytes grow to several different sizes, while all B cell lymphocytes are generally the same size. Both kinds of white blood cells develop in bone marrow, but some travel to different areas of the body to mature. They also perform slightly different functions, though both kinds of lymphocytes attack invasive cells and tissue.
T cell lymphocytes develop inside the bone marrow, produced by stem cells there. They then transfer to the thymus gland where they develop completely. These lymphocytes then travel to lymph nodes, where they’re transferred to the blood stream, if necessary. The majority of T cells are extremely small, but a handful of these cells grow to about twice the size of the rest. The large T cells are like the tanks of the immune system, while the small cells are like the cavalry.
All T cell lymphocytes take care of cell-mediated immunity. This means that when a cell or group of cells signals that they’re in distress, a group of T cells rushes to the site to absorb and destroy the irritation. The irritation could be bacteria, a virus, or excess waste. Viruses are especially nasty because they replicate inside cells, causing them to burst. It often takes the work of thousands of small, mature lymphocytes, as well as a handful of larger T cells, to take care of these invaders.
B cell lymphocytes also develop in the bone marrow, but they mature there as well. Mature lymphocyte B cells then travel constantly throughout the body, a bit like sentries. When these lymphocytes detect an invader in the body, they turn into plasma that produces antibodies. This is called a humoral immune response because the B cells turn into plasma, which is a humor — or secretion — in the body. It contains no actual cells, just antibodies. Many antibodies remain in the bloodstream after the threat is removed, which is why it is impossible to catch the exact same cold or flu twice.
All mature lymphocytes work together when there’s a threat to the body. As mentioned above, B cells act like perimeter guards. When they turn into antibody-producing plasma, T cells swoop in to attack the invading force as well. Sometimes just one group of lymphocytes will attack, but this doesn’t happen often. The body produces both kinds so they can work in conjunction.
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The five modern web browsers are Internet Explorer, Firefox, Safari, Chrome and Opera.
DashingD3js.com will focus on the web browsers that use WebKit.
WebKit is a layout engine software designed to allow web browsers to render web pages
WebKit powers the Apple Safari and Google Chrome browsers.
We will use Google Chrome for the rest of the sections for the Web Inspector Developer Tool.
More details below.
Much much later, we will get into cross-browser compatibility.
The web browser's main function is to display a web resource.
The browser requests the resource from the server and displays the resource in the browser window.
The resource can be HTML, images, PDFs, text, or other media.
The web browser requests a resource from the server using the Uniform Resource Identifier (URI) of the resource.
For most cases, the URI is actually a URL.
A URL is the Uniform Resource Location.
URL refers to location and URI refers to identity.
After the browser receives the requested resource it must interpret and display the resource.
The way a browser interprets and displays HTML and CSS files is specified in the HTML and CSS specifications.
HTML5 and CSS3 are specific HTML and CSS specifications.
The Hypertext Markup Language (HTML) resource is the main markup language for displaying web pages.
HTML elements are the building blocks of the HTML web page.
The elements consist of a pair of tags (starting and ending tags) and the textual or graphical content inside of the tags.
Inside of the tags, different attributes can be given.
The starting HTML webpage we will use is:
You can read more about HTML here =>HTML
The Cascading Style Sheet (CSS) resource is the style sheet language used for describing the presentation of the document.
The presentation includes both the look as well as the formatting.
CSS can be applied to HTML, XML, and most importantly for D3.js Scalable Vector Graphics (SVG).
CSS formatting can be applied to html elements as an attribute.
The "Style" part of the line is the style sheet language describing that the font-size should be 12 pixels.
When the CSS formatting is applied directly to the html element as an attribute, it is called "in-line css".
The are two other main ways to add CSS formatting to HTML elements.
One is to put it at the top of the HTML file (See lines #5 - #7).
The other way is to put it into a different file that the HTML code references (See line 5).
The examples and sections will show the CSS in a separate file.
This will makes the Web Inspector easier to use.
CSS works by attaching a rule to an HTML element.
Here, "p" is the HTML element the style sheet is selecting and the font-size is the rule that it is attaching.
You can read more about CSS here => CSS
For D3.js purposes, we will use it to write functions to interface with the data and D3.js.
In the Body (note the starting and closing tags):
At the Head, in another file:
Document Object Model (DOM)
Document Object Model (DOM) is a convention for representing and interacting with objects in HTML, XML, and XHTML documents.
The DOM is separated into three parts: Core, HTML, and XML.
The DOM allows programs and scripts to dynamically access and update the structure, content, and style of a document.
A DOM structured document has a DOM Tree which can be used to address, manipulate, and navigate the structure of the Document.
The structure of the DOM Tree is can be navigated in reference to relationships of its branches.
This gives us descendant, ancestor, as well as parent, child and sibling.
Thus we can specify a particular element in the DOM, look at the DOM tree, and select all of the elements above, below or along it easily.
The p element has a parent => body
The p element has a sibling => input
The p element has a child => span
This allows us to access and update the structure, content, and style of the selected elements.
You can read more about the DOM here => Document Object Model (DOM)
Scalable Vector Graphics (SVG)
Scalable Vector Graphics (SVG) is a family of specifications for creating two-dimensional vector graphics.
Vector graphics are not created out of pixels.
Vector graphics are created with paths having a start and end point, as well as points, curves and angles in between.
Since Vector Graphics are not created out of pixels, they can be scaled up to larger or smaller sizes without losing image quality.
SVG images and their behaviors are defined in XML text files.
The XML text can be included in an HTML document.
This text means that images can be created and edited in a text editor.
Also, since the DOM includes XML as part of the DOM specification, we can use the DOM Tree to access and update the structure, content and style of SVG Images.
SVG comes with a basic set of shape elements:
- Straight Line
Rectangle Example & Code:
Circle Example & Code:
Ellipse Example & Code:
Straight Line Example & Code:
Polyline Example & Code:
Polygon Example & Code:
From all of these examples, you can see the power of Scalable Vector Graphics (SVG).
We will use these basic shapes in many of our D3.js Data Visualizations.
The Web Inspector comes with WebKit based browsers.
We will use Chrome's Web Inspector.
This is what it looks like:
We use the Web Inspector to see the current state of the DOM.
Lastly, the Web Inspector also lets you highlight an element, right click on it, and then Inspect the Element:
This allows you to see the DOM elements for the specific thing you highlighted on your screen.
You can read more about the WebKit Web Inspector Tools here =>