Roy,

You have more info on Guyot than any other source I am aware of. There is little known about Nicolas Guyot. His store at 12 Rue De Ponthieu a Paris arr. VIII is a high rent district of Paris even today. The original building is gone. He is listed as an Arquebusier a Paris, a gun dealer in Paris. He was present at the 1889 Paris Exposition according to one source, but I can find no record of him there.

Pete