Was talking to the "older version of me" about dividing heads and rotorey tables. He said that the primary function of the dividing head was for cutting gears. Today everyone just goes out and buys gears, They are cheap. I replied that there may be a time when when you have to make one. "True enough son" was his reply. He was "An able bodied seaman" And a machinist.
Military Manuals U.S. Navy- Machinist and Machinery Repairman 1 and C Two of Three
U.S. Navy Machinist and Machinery Repairman course Part two of Three