Even in the simplest form of fracture, if the splints or bandages are improperly applied and the fractured bone left so loosely guarded that the broken ends move one upon another, the formation of the calluses previously described is liable to be interfered with, and in place of a strong, rigid, and healthy union a formation of elastic cartilage is the result.
"Special Report on Diseases of Cattle"
U.S. Department of Agriculture J.R. Mohler
Corns, calluses, and Warts.
"A Handbook of Health"
Woods Hutchinson
It'd be a shame to let you go to waste simply raising calluses on your hands."
"Black Jack"
Max Brand