In the 19th century manuals such as Gunn’s Domestic Medicine promised that “any man, unless he be an idiot or an absolute fool,” could perform an amputation. But Pennsylvania surgeon George Griswold had found that “persons unskilful in the use of the saw, and even the most experienced, will find it difficult to hold the bone firmly,” increasing both the patient’s pain and length of the operation. He invented this “amputator’s assistant” to hold a limb steady while a surgeon saws through it.

He patented it in 1854, only seven years before the Civil War. I haven’t been able to learn how widely it was used.