The Push-In Spinning Corkscrew: A Steep Twist That Turns Itself Into the Cork

"I construct my screws of steel in the form known as the 'convex twist,' but to avoid the slow process of turning them into a cork by the handle, I give an increased pitch to the thread, as shown at A, Fig. 1, and make it sharp or very thin upon the edge." "The operation is as follows: The point of the screw being pressed into a cork, the pin P rises above the catch K, and the center c meets the corresponding center c′, and the great pitch of the thread causes the screw to revolve rapidly through the cork; but when pulling upon the cork the pin P falls back upon the ring n and revolution is stopped by the catch K."

**Screw.** Cut 15 cm of 12 × 3 mm mild steel flat bar. Grind one end to a point. Heat the last 6 cm red with the torch and, holding the point in the vise, twist the bar with an adjustable wrench about one and a half turns, so the twist has a long lead. File its edges thin. Leave the rest of the bar straight as the shank and file it round at the top into a blunt point, the centre c. **Handle.** Turn or rasp a hardwood handle. Drill it through along its axis to take the shank loosely, and enlarge the top of the hole so a pin through the shank can move up and down. Screw a small screw with a centre-punched head into the top as the centre c′. **Pin, ring and catch.** Drill the shank across for a pin P. Fit a washer with a notch round the hole's mouth as the ring n, and drive a short nail into the wood beside the notch as the catch K, so the pin rests on the ring against the catch when the shank hangs down. **Test.** Cork several bottles of water with the corking kit. Press the screw's point into a cork without turning the handle and see whether it spins itself in. Pull, and see whether it holds and draws the cork.

**Joseph Linus Clark** of Chester, Middlesex County, Connecticut, received US 45,137, dated 22 November 1864. He bored his wooden handles H to let the shank move up and down and revolve, protected the wood with a metal ring n notched on one side, drove the catch K into the wood at the notch, and set a metal centre c′ in the top on a screw S. He claimed neither the convex twist nor the handle's form, but the increased pitch combined with the pin P and catch K. **Honest limits.** A twisted flat bar and a screw head stand in for his steel twist and metal centre. The notebook's condition is a rough guide that ignores the cork's resistance to cutting; its diameters, leads and friction coefficient are examples. Your pressed-in corks are the result.