Well, the information that I have found is that Pettibone was a clerk with John Boner until 1871. He took over the business from Boner in 1872 and the Pettibone firm existed until 1975 in one form or another. Items with the Pettibone name are often seen.

I have hear a lot of talk about 1860's with diamond versus eliptical cross-sections on the blades - but, I don't know if there is any real cut and dried conclusions that have ever been drawn.

Hope that this is of use. - Gene