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An Encyclopedia of the History of Technology part 101

An Encyclopedia of the History of Technology part 101. This one of a kind encyclopedia presents the entire field of technology from rudimentary agricultural tools to communication satellites in this first of its kind reference source. Following an introduction that discusses basic tools, devices, and mechanisms, the chapters are grouped into five parts that provide detailed information on materials, power and engineering, transportation, communication and calculation, and technology and society, revealing how different technologies have together evolved to produce enormous changes in the course of history | PART FIVE TECHNOLOGY AND SOCIETY with a wet wad placed between the charge and the shot in order to prevent premature detonation or cock-off . At sea chain-shot two roundshot linked by a chain was often used to cut the enemy s rigging. Varieties of grapeshot normally musket balls in a container were available to engage infantry and cavalry at close quarters. Priming became more efficient in the early 1700s with the introduction of a powder-filled tin tube which was inserted in the touch-hole and bag charges measured amounts of propellant sealed in canvas bags. The early part of the eighteenth century also saw the first serious attention being paid to the science of ballistics. Before then guns were either laid directly that is by lining the target up with the line of the barrel or by using a gunner s quadrant for longer ranges than point blank. This consisted of two arms one longer than the other with a metal arc between them marked in 12 intervals and a plumb line. The longer arm was placed in the bore and the angle of aim above the horizontal indicated by the plumbline. Each marking on the arc was known as a point and range was calculated in terms of the number of times above point blank range that each point represented with 45 mistakenly believed to be the correct setting to achieve maximum range for the piece. The first development was the drawing up of mathematical rules for firing mortars by the Frenchman de Blondel who drew largely on Galileo s work on the laws of movement. Little note was taken of de Blondel in military circles but another Frenchman de Bélidor in his Le Bombardier français 1731 went several stages further publishing complete tables of ranges for charges and elevations and furthermore proved that the charges currently used were excessive resulting in premature wearing of barrels and carriages and thus decreasing accuracy. Until this time there had been a long-held theory that the ideal weight of charge was two-thirds that of the shot but as