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A firearm can be used primarily as a tool, instead of as a weapon, to project either single or multiple objects at high velocity through a controlled explosion. The firing is achieved by the gases produced through rapid, confined burning of a propellant. This process of rapid burning is technically known as deflagration. In older firearms, this propellant was typically black powder, but modern firearms use smokeless powder, cordite, or other propellants. Many firearms such as mortars do not have rifled bores to impart spin to the projectile for improved flight stability, such as is seen with firearms used as weapons, although some are rifled. The lack of rifling can prevent tangling of grappling hook lines, buoy lines, and such, although some firearms intended for use at the longest ranges in these applications are rifled. ==Line throwing== The Manby Mortar was invented by Captain George William Manby, also the inventor of the portable fire extinguisher. On 18 February 1807, Manby looked on helplessly as a Naval ship, the ''Snipe'', ran aground 60 yards off Great Yarmouth during a storm. By some accounts, a total of 214 people drowned, including French prisoners of war, women and children. Following this tragedy, Manby experimented with mortars, and so invented the Manby Mortar, later developed into the breeches buoy, which fired a thin rope from shore into the rigging of a ship in distress. A strong rope, attached to the thin one, could then be pulled aboard the ship. His successful invention followed an experiment as a youth in 1783, when he shot a mortar carrying a line over Downham church. His invention was officially adopted in 1814, and a series of mortar stations were established around the coast. The Manby Mortar was used by the Waterguard and later by H M Coastguard for many years. The first recorded rescue using the Manby mortar was on 18 February 1808; Manby himself was in charge of the mortar and a crew of seven were brought to safety from the Plymouth Brig ''Elizabeth'' stranded off the shore at Great Yarmouth. A Lyle gun was used to shoot a line towards people in distress in order to rescue them and save their lives. The Lyle Gun was toted to the shoreline usually by Surfmen that manned the L.S.S using the tool. The iron wheels that supported the cart had wide bands on the outside the wheel to keep it from sinking into the soft sand especially when it came to being used on the beaches of Cape Cod and other stations along the east coast of North America. The projectile that carried the line to the craft in distress was fired over the ship to ensure its target. The line fired to the ship in distress was one of several designed to support the breeches buoy which would carry survivors back to shore on a line that would take them over the waves. The Lyle gun could shoot a projectile about 300 yards. Examples of later firearms based upon the Lyle gun are widely seen in maritime museum displays, such as at the Sleeping Bear Point Coast Guard Station Maritime Museum in Glen Haven, Michigan. The exhibits there focus on the U.S. Life-Saving Service, the U.S. Coast Guard, and Great Lakes shipping history. In the summer, demonstrations are given of rescue drills and equipment used to fire a rescue line from shore more than to a ship in "distress". 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Firearm (tool)」の詳細全文を読む スポンサード リンク
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