January 9, 2008
The compound bow in archery was a revolutionary invention that has changed the sport forevermore. The compound bow in archery was invented in the mid 1960s by an American engineer named Howless Wibur Allen. In 1961 he got inspired by the then launching of Hoyt Pro Medalist Bow. This bow was one of the very first to have vertical stabilizers on it, and Allen had another idea to add to it-the wheel. He harnessed the principle of the block and tackle pulley to the bow and felt (correctly) that this would enhance a bow’s performance. The mechanics of the pulley system would, he reasoned, allow a heavier weight to be drawn. After continued experimentation he found that round pulleys and cam-shaped wheels worked best and they were riding on off-set axles called “eccentrics”. The compound bow reaches its peak weight in the middle of the draw; beyond this point as the archer continues to draw back the weight of the draw is significantly reduced, allowing an average-sized archer to comfortably hold a very heavy weight. The compound bow in archery gives an amazing flat trajectory to an arrow’s flight.
It actually took several years for Allen to get anyone to manufacture his new invention, the compound bow. American laws prohibited the use of mechanical devices attached to bows. So, the compound bow could not be used for hunting nor in competitions. Allen began making his own bows, sure that they would catch on so strongly that the laws would be rewritten (and he was once again correct). However, when he was making his own compound bows he realized that he had a design flaw, as he kept on stripping the fletching off his arrows. The crossing cables in the center of the bow were interfering with the arrow’s flight. By 1967 Allen had figured out that he needed to add an extra set of “idle” wheels that got mounted at the center of each limb. These idle wheels were set at 90 degree angles to the limb-tip, and this allowed the cables to now cross to one side of the center line so that they no longer interfered with the arrows’ flight path. With more research, Allen added riser-mounted adjusters so that the archer could use different cable lengths to attain different weights. These adjusters were gear-driven and acted very much like the machine heads for tuning a guitar.
By this time, the compound bow or “Allen bow” was a superior instrument. The flatter and faster trajectory that an arrow could be given due to the increase in stored potential energy meant that now a heavy hunting arrow would be able to find its mark more often and would fly with greater speed. The lighter weight as compared to a recurve bow of the same draw weight meant that this bow was more comfortable to use, as well. However, the sport’s governing body still would have nothing to do with it.
However, the famous American archer and archery magazine editor Tom Jennings love the idea and he used his pull to get the governing body to begin reconsidering its stance. Jennings published an article titled “A Bow with a Compound Interest”. From there, the compound bow found its way into archery.
For Health related articles and information visit health-information-articles.com
Download 100 free wealth Creation e books from mymillionairebuddy.com
Practice your Creative Writing skills at Objectwriting.com
Find out about the art of songwriting and recording at home at myhomerecordingstudio.com
Filed under: Archery
- Article Source : http://www.originalreviews.com/?s=free+archery+books
Sunday, January 20, 2008
January 9, 2008
Posted by Rıdvan Uzuntaş ; at 8:05 AM
Friday, January 18, 2008
2nd Bow, Turkish bow
Ten things 2007 - a class with Michael Shanks about design
The design and material of the bow change to suit its archer. One of such bow is composite bow. By definition, composite bow is bow made of more than one material. A Mamluk bow manuscript describes one such bow,
“The best bow should be composed of four substances: wood, horn, glue and sinew. There is a wonderful wisdom in this. That wisdom is this: Human beings consist of four substances: bone, sinew, blood and flesh. The composite bow also consists of those four substances. The wood corresponds to bone in man. The horn corresponds to the flesh in man. The sinew is like the sinew of man. The glue is like the blood of man.”
The passage personifies the bow. The bow is not just a tool but a projection of its user. The drawing method of Turkish archer is quite different from modern archery. Instead of using index, middle and ring finger, Turkish archer uses his thumb to draw the bow which is drawn to the ear lobe. According to the manuscript, “The limit of the correct draw should reach the lobe of the ear. It shouldnot be less than that. If it is, it is a mistake.” This method of drawing is also used by the Mongols and the Huns. This drawing method is effective for horse archery because the archer can draw and hold the rein at the same time.
Composite bow is very flexible and compact. This makes it easier to carry on horseback. A picture is worth a thousand words. Look at the picture below.
Another interesting thing about Turkish archers is the existence of the manuscript on archery itself. The author of the manuscript explicitly refered to other manuscript which he used as a reference:
"Be it known to you that the reason for composing this treatise was that (a turkish name, probably a sultan) summoned me, this weak and miserable one. He placed several books on archery written in Arabic before me, and he requested from me ... that I write a book on archery in Turkish using these and other books."
The existence of many books on archery indicates a special status of archery in medieval middle east. The manuscript's content is pretty much a coaching and how-to manual on archery. For my research, I found only two or three books in Green library that are meant to be a guide book on archery like the manuscript. Furthermore, it indicates a more important thing about Turkish archers: they were literate or else the books would be useless. The practice of archery must have been common among middle eastern medieval warriors.
A few interesting excerpt:
"Know and be aware that God,..., made archery and raising horses with the intention to fight a farz (religious obligation). As God,...has stated in Koran..."Make ready for them whatever force and strings of horses you can." "
"The Apostle of God said: "Whoever shoots an arrow in the way of God...God will give (him) a reward amounting to what is granted for freeing a slave,...the Prophet said:"He who learned archery and then gave it up, verily he disobeyed me."...The Apostle of God said:" he who learns archery and then gives it up and no longer shoots arrows is not one of us."
Posted by Rıdvan Uzuntaş ; at 9:01 PM