Do a search on Capt. Benjamin Merrill, I did and there was pages of websites for him. In one site it said, when he moved to N. Carolina he built a boring mill on a creek that ran through his land. He would set up a iron bar to be bored in the afternoon and by morning it has finished an ready to be used. I found an old lock (flint) on EBay for sale. It was found in a old house along with some ML rifles and the rifle the flintlock came out of that had been converted to percussion. The house was built in 1832 in Mississippi by some of B. Merrill's descendants and the guns was said to have been made by him. The old house had been used for storage until it was tore down in the early '60s, that was when the guns was found in a back room. That is all I know for now.
Help me out, read some of the websites and let me know if you find out anything, you can send me a PM. I read the first 5 or 6, I read so much about Merrill's I was sick of my self
And yes they were prolific seeing we all came from one man, a Nathanial Merrill, according to one website. And the spelling, Merrill an Merrell was used in the same family. Good Luck cuz
AL
P.S. Where do you live. I live in Southern Illinois