The cow femur, typically between 17-18 inches, provided 6-8 strong, straight toothbrushes.
Though toothbrushes were manufactured from bone and bristle for more than one hundred and fifty years, the process changed little. Bones were first boiled to remove any meat that remained. The joints were cut off, leaving just the straight bone. To make toothbrush handles, bones would be cut to size, shaved, polished, smoothed, and drilled. The process of making a bone handle took forty specific, skilled operations.
Woodworking tools like this lathe could be used to manufacture bone handles as well as to fashion wood pieces. (J. S. Zerbe, Carpentry for Boys; In a Simple Language, Including Chapters on Drawing, Laying Out Work, Designing and Architecture With 250 Original Illustrations. New York, New York Book Company, 1914. Reproduced at Gutenberg.org)
The tools required to make toothbrushes, and those used to make paint or shaving brushes were similar. An 1838 inventory of the Taylor & Souther Co. of Lowell, Massachusetts reveals that the brush factory had tools — including bow saws for cutting handles and boring lathes for drilling holes for bristles — that could be used for producing any kind of brush. Between the time brush manufacturing began and in the 1930s when synthetic brushes were developed, the tools and techniques used to make brushes changed little.
Disposable America 