You're viewing this item in the new Europeana website. View this item in the original Europeana.

Brown - figure 111

Micrometer screw. Great power can be obtained by this device. The threads are made of different pitch and run in different directions, consequently a die or nut fitted to the inner and smaller screw would traverse only the length of the difference between the pitches for every revolution of the outside hollow screw in a nut.