when was the double edged safety razor invented
Safety razor A third pivotal innovation was a safety razor using a disposable double-edge blade that King Camp Gillette submitted a patent application for in 1901 and was granted in 1904.[3] The success of Gillette's invention was largely a result of his having been awarded a contract to supply the American troops in World War I with double-edge safety razors as part of their standard field kits (delivering a total of 3.5 million razors and 32 million blades for them). The returning soldiers were permitted to keep that part of their equipment and therefore easily retained their new shaving habits. The subsequent consumer demand for replacement blades put the shaving industry on course toward its present form with Gillette as a dominant force.[4] Prior to the introduction of the disposable blade, users of safety razors still needed to strop and hone the edges of their blades. These are not trivial skills (honing frequently being left to a professional) and remained a barrier to the ubiquitous adopting of the be your own barber ideal.[5]
Vein Veins are less muscular than arteries and are often closer to the skin. There are valves in most veins to prevent backflow.
Gilbert Gottfried In March 2011, Gottfried made a series of jokes on his Twitter account about the
Standard deviation Let X be a random variable with mean value Î¼:
Fleming's right-hand rule These mnemonics are named after British engineer John Ambrose Fleming, who invented them.
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