Some general comments on old French goods wagons. Generally they were iron framed, and early ones could have very noticeable axleguards with the diagonal braces splayed very widely. Spring suspension was noteworthy in having the leaf springs ending in short swing links, rather than ending in plain shoes under the solebar like British wagons. Some extra clearance was allowed for between the axleguards and axleboxes, and this gave an easier ride. You could see a similar arrangement on GWR brake vans, for the same reason.
Plank widths could vary quite widely, some wagons having quite narrow planking. One distinctive feature on NORD wagons was having diagonal planking, and this was done to a lesser extent on OUEST wagons. You can see it on the ETAT wagon drawing for just the side doors. Side doors on open wagons were normally cupboard type, rather than drop, as on English wagons. Vans were constructed with apertures in the upper part of the sides, which could be closed by shutters, either hinged or sliding, on the inside or outside of the body. I would think this was to give dual purpose usage, either for general merchandise or cattle transport.
The majority of wagons had no brakes of any kind. There is a video showing loose shunting in sidings where slippers were placed on the rail, and these were squeezed along the rail by the wagon wheel, retarding it. Fourgons had brakes applied by a screw, but these were marshalled at the head of the train, like a passenger train, rather than at the rear as in Britain. The rearmost vehicle was a goods wagon fitted with screw applied brakes, with a small box for the brakeman to shelter, and he would keep the train stretched to avoid snatching, and look after breakaways. similar vehicles were scattered along the length of the train, and presumably manned depending on the speed and terrain. I’ve tried to estimate the proportion of braked to unbraked wagons, looking at photos of sidings, and it seems around one in four, to one in five. I’m fond of their appearance, and running short trains, I end up with nearer one in two. It would appear that brakes applied by a side lever appeared in the twentieth century, but were not universal. Air braking also started to be applied from roughly 1890, and new wagons with airbrakes also had longer bodies, higher capacity, but also longer wheelbase, to improve track running for higher speeds. Freight train operation could then be classed as “RA” (regime accelere) for fast services, and “RO” (regime ordinaire) for slow unbraked trains, with older designs of wagons.
I cobbled up some drawings for EST wagons, using the Denis Allenden ETAT drawing as a basis, and working off various photos, so you’ll appreciate they’re not exact by any means, but gave me a basis to work off, so here’s some opens (tombereau), vans (couvert), and brakevans (fourgon)