looking at the tables here on the "Useful info" section, it seems to be made in 1891 or 2.
I couldn't see for sure from the pics...the bbls look like fluid steel? ,are they?
As a lover, but no expert on Francottes , I'd say it was one of their lower/mid priced basic boxlock.
Who knows what has gone on inside..the bent nail doesn't bode well, but you never know.
Get it to a good Gunsmith, pay him to tell you whats wrong with it & how much it'll cost to make it into a shooter....then add the sentimental value & see how you feel about the numbers.
If it checks out ok bbl wise, & its not too bad inside, you could have a nice, sentimental shooter for ????.....hopefuly not too much
Please let us know how it works out