<P> Screws were very hard to produce before the First Industrial Revolution, requiring manufacture of a conical helix . The brothers Job and William Wyatt found a way to produce a screw on a novel machine that first cut the slotted head, and then cut the helix . Though their business ultimately failed, their contribution to low - cost manufacturing of the screw ultimately led to a vast increase in the screw and the screwdriver's popularity . The increase in popularity gradually led to refinement and eventually diversification of the screwdriver . Refinement of the precision of screws also significantly contributed to the boom in production, mostly by increasing its efficiency and standardizing sizes, important precursors to industrial manufacture . </P> <P> Canadian P.L. Robertson, though he was not the first person to patent the idea of socket - head screws, was the first to successfully commercialize them, starting in 1908 . Socket screws rapidly grew in popularity, and are still a favorite of mechanics today for their resistance to wear and tear, compatibility with hex keys, and ability to stop a power tool when set . Though immensely popular, Robertson had trouble marketing his invention to the newly booming auto industry, for he was unwilling to relinquish his patents . </P> <P> Meanwhile, in Portland, Oregon, Henry F. Phillips patented his own invention, an improved version of a deep socket with a cruciform slot, today known as the Phillips Screw . Phillips offered his screw to the American Screw Company, and after a successful trial on the 1936 Cadillac, it quickly swept through the American auto industry . With the Industrial Revival at the end of the Great Depression and the upheaval of World War II, the Phillips screw quickly became, and remains, the most popular screw in the world . A main attraction for the screw was that conventional slotted screwdrivers could also be used on them, which was not possible with the Robertson Screw . </P> <P> Gunsmiths still call a screwdriver a turnscrew, under which name it is an important part of a set of pistols . The name was common in earlier centuries, used by cabinetmakers, shipwrights, and perhaps other trades . The cabinetmaker's screwdriver is one of the longest - established handle forms, somewhat oval or ellipsoid in cross section . This is variously attributed to improving grip or preventing the tool rolling off the bench . The shape has been popular for a couple of hundred years . It is usually associated with a plain head for slotted screws, but has been used with many head forms . Modern plastic screwdrivers use a handle with a roughly hexagonal cross section to achieve these same two goals, a far cry from the pear - shaped handle of the original 15th - century screwdriver . </P>

When did phillips head screws come into use