Straight razor King C. Gillette: a double-edged safety razor with replaceable blades. These new safety razors did not require any serious tutelage to use. The blades were extremely hard to sharpen, and were meant to be thrown away after one use, and rusted quickly if not discarded. They also required a smaller initial investment, although they cost more over time. Despite its long-term advantages, the straight razor lost significant market share. As shaving became less intimidating and men began to shave themselves more, the demand for barbers providing straight razor shaves decreased. Since 2012, production of straight razors has increased multifold. Straight
Safety fuse Safety fuse The safety fuse is a type of fuse invented and patented by English inventor William Bickford in 1831. Originally it consisted of a "tube" of gunpowder surrounded by a waterproofed varnished jute "rope". It replaced earlier and less reliable methods of igniting gunpowder blasting charges which had caused many injuries and deaths in the mining industry. The safety fuse burns at a rate of typically about 30 seconds per foot (1 second per cm). Documented evidence suggests that the earliest fuses were first used by the Chinese between the 10th and 12th centuries. After the Chinese had invented