Cat breaker
A "cat breaker" is a type of tool used to break or crush catgut, which is a type of cord or string made from the dried and processed intestines of animals, typically sheep or goats. Catgut was commonly used in the past for making strings for musical instruments, particularly violins and other stringed instruments.
A cat breaker is typically a small, handheld tool with a sharp edge or point that is used to cut or crush the catgut into smaller pieces or to break it down into individual strands. This is often necessary when preparing catgut for use as a string, as it needs to be cut to the correct length and thickness to produce the desired tone and playing characteristics.
Cat breakers are still used today by luthiers (stringed instrument makers) and musicians who work with traditional instruments that use catgut strings. However, with the advent of modern synthetic strings, catgut is no longer as widely used as it once was, and the demand for cat breakers has decreased accordingly.