A Lyle gun was a line thrower powered by a short-barrelled cannon. It was invented by Captain David A. Lyle, US Army, a graduate of West Point and the Massachusetts Institute of Technology and were used from the late 19th century to 1952, when they were replaced by rockets for throwing lines. History Earlier line thrower designs date back to the late 18th century, with the Manby mortar saving lives as early as 1808 when the crew of a brig was rescued at Yarmouth by the use of the device fired from a carriage gun and supervised by captain George Manby. A rocket-based system was also devised by British engineer Henry Trengrouse in 1808. Sumner Increase Kimball, the first and subsequently only superintendent of the United States Life-Saving Service, wanted to find a better line-throwing device. Kimball engaged the help of the United States Army Board of Ordnance and in 1877 they assigned David A. Lyle (1845–1937), a first lieutenant, who began research and testing that resulted in reliable efficient designs. Lyle developed 3 bronze, smooth-bore guns of different sizes and the gun became the USLSS standard line-throwing gun. Projectiles for the gun were made of cast iron with a wrought iron eye bolt screwed into the base as an attachment point for the shot line. The projectile for the gun was long and weighed . It was placed into the gun barrel so the eye bolt with the line attached was sticking out. After firing, the projectile rotated so that the eye bolt and line were trailing. The gun had a large recoil from firing. A standard charge of of gunpowder would knock the gun back . The maximum rescue charge of would send the gun flying back even further. The type of gunpowder used was also critical. It was a variation of black powder, uniform grain size, marketed as Hazard’s Life-Saving Service Powder and DuPont Life-Saving Powder. Shotline was also just as critical to the accurate operation of the Lyle gun. Hemp line was found to be too brittle. Braided linen was usable, but it was too heavy with sea water after it was fired and had to be dried out before firing again. The best line was waterproofed braided linen. It cut through the air best and provided improved range. New lines were too stiff and were difficult to properly fake (to wind in a pattern so