History: Simple corkscrews

Simple corkscrews, leave the operator to do the work of screwing in the worm and pulling out the cork unassisted. Various modifications of handle, shaft, and worm can increase the efficiency of these manœuvres: the handle should be formed to give a good pulling grip; the shaft can be fitted with a metal disc, or button, to obtain more complete contact with the cork; and the worm should be a steel helix 5.7 cm/2.2 in long, of good open pitch, and have an outer diameter of between 0.8 and 1 cm.