POSTMEN USED TO TEST TANNING PROCESS (Jun, 1930)

POSTMEN USED TO TEST TANNING PROCESS

One of the most unusual scientific laboratories in the world is a pair of shoes. When chemists of the United States Department of Agriculture, in Washington, D. C, recently wished to test the relative wearing qualities of shoe-sole leather produced by two different tanning methods, they sought the aid of postmen, who are proverbially-hard on their shoes.

In the test, the postman took his shoes to the chemists who equipped them with new half-soles. One half-sole was the result of vegetable tanning processes in which such materials as hemlock bark, chestnut extract, and mangrove bark are used. The other shoe was soled with leather tanned by the chrome process,
which employs chemicals.

The number of hours the shoes were worn was recorded and the results tabulated. It was found that the chrome sole outwore its mate in some cases as much as eighty percent. However, it absorbed water faster and was slippery on wet pavements. As a guarantee that the soles would be exactly alike except for the difference in the way they were tanned, the chemists took hides of the best quality, cut them in half, and cut the mated soles from identical positions.