Language and technology evolves every single day. Think back to when you would not have known what a hard drive is. Also, have you ever heard of a besom maker? If I instead said a broom maker you would know, right? Again, language changes.
My point is that you need to probably include a little more about this person. What year are we talking? Did they live in the country or the city? Were they wealthy or not? All of that will affect the outcome and we can better perform a process of elimination.
More handwriting samples would be essential. We've nothing to compare the letters to, in order to figure out what they are.
Also, you may want to cross post this to a French board. Someone who researches a lot of French may recognize this.
Sorry I couldn't be more helpful, but I thought I'd at least offer some ideas on finding the answer.