Two weeks ago I acquired a French Bassoon. It was found in a middle school’s band room cabinet and had been neglected for many years. There is no manufacturer’s mark, the usual branding spot is the low D guard and this one has been removed. My best guess is either Selmer or Buffet. Also, my time with this instrument hasn’t been true to the period since it lacks a french bocal. Initially I could hardly get any sound to come out of it, I realized that some of the pads near the top of the tenor joint were leaking. So I did a temporary fix by wrapping the pads in plumber’s tape.
The fingering schematic of the lowest tritone is completely different from the German system bassoon. Luckily the Weissenborn method book comes with a full french bassoon fingering chart. After a bit of work, the layout of the low keys makes sense and it is just as fast as the German system. The one consistent problem is the transition from D flat to E flat. The rest of the instrument is very similar to the German system with slight modifications, especially in the highest notes.
I did some research into french bassoon reeds to try and create something that would work well for this system. Most of what I saw was a narrower shape with a longer blade and tube. What I decided to do was to use my regular Fox 2 shaper which is a bit narrow and leave a long blade. I found some great french bassoon reed images on the International Double Reed Society’s website under the “Reed Project” tab. There are reeds gathered from top double reed players from all around the world. I’m not sure if this link inly works from member but here it is.
http://idrs2.colorado.edu/reed/Reeds.html
The tone of the French bassoon is more muffled and nasal. It really reminds me of baroque bassoon tone but with less stability. The instrument doesn’t project as well, it seems stuffy without any “sparkle” to the sound. Also the half step isn’t clearly defined for most of the notes. The pitch center of the basson is very flexible and is stabilized with modified fingerings to bring the pitch up or bring the pitch down. My goal for this instrument is to eventually play the Saint Saens sonata on it and Daphnis and Chloe suite 2.
Kristopher King 
I shee ,not original bocal on this instrument,that first you must find.Other or german bocals are not working on this very complicates instrument,Also reeds and fingering chart look for oubradous french bassoon studie,Make i bic smile on your mouth,do not play as german instrument. A lot off work also look on youtube french bassoon Bolero radio france,This french bassoon player you can watch how to play it. I did also this eperiment,normal i play on Heckel bassoon.Look out moutpieces will give problems!!
Another french bassoon manufacturer http://www.ateliersducasse.fr/
I also recently came by a French bassoon (but made in Boston by H, Bettoney) that looks nearly identical to the one in the middle of your photo above. It is also missing the bocal and needs new pads. I will be very interested if you find a bocal that hits the sweet spot for this instrument you have. I think the Bettoney is a copy of your French model. It is from the early 20th century when Bettoney prided themselves for instruments “undistinguishable in any way from the best French” models. FYI, another player was using a #2 bocal of some type with one of these Bettoney French copies but did not specify anything else. Regards.