Froe
The froe looks like a cross between a thin axe and a straight scythe. It was used to split wood along the grain to create thin pieces for use as shingles, clapboards or barrel staves.
Adders
Adders were an early form of calculator popular in the 19th century. The Webb Adder is a better known example of this type of device, and is made of a metal circle and dials. It was patented in the late 19th century. The Hart Patent Adder is a rarer version and was used earlier.
Bull's Head Can Opener
Distributed among U.S. soldiers during the Civil War, this can opener is shaped like a bull and was used to open "bully beef" (cans of shredded beef and gravy).
Fordson Tractor Wrench
Made to service the English Fordson tractor, this wrench was made with a curved handle. The handle has a snail logo for Snail Brand tools, a division of Smith Francis. The English Fordson tractor was developed in 1917.
Antikythera Mechanism
Found in the remains of a sunken Roman ship in 1902, this astrolabelike device was in 81 fragments and is a puzzle to archaeologists. It was made around the 1st century B.C. and is the most complex technology attributed to this time period. It is thought to have been used to track and predict the movements of heavenly bodies.