The Belmont interchangeable was Bonehill's gun having interchangeable parts.
There were others which had preceded Eli Whitney in making guns with parts "Made to Gage" to be interchangeable, but Whitney I believe carried it to a higher level & received most of the honor in the process.
There are so many things we have been taught in History classes that are wrong that it is often hard to sort out the truth. For instance how many know that after Cyrus McCormick had his reaper ready for the market, he had to wait 13 years for another man's patent on actually an advanced design to expire before he could sell his. Mr Hussey believed the old saying "Build a Better Mouse Trap & the World Will Beat a Path to Your Door". The Crowd didn't come, he sold a few locally. McCormick, on the other hand, beat a path to the World & received the credit for inventing the Reaper, which he didn't do. Likewise, Elias Howe Jr did not invent the Sewing Machine, in fact, he was never even a successful builder of them. He was issued a patent which should not have been granted which tied up other makers & he Bled the trade of some 3 million dollars & History has credited him with the invention.
