Hello Maggi
Prior to the time you mention (Early 1850s) the very first Railway build
contracts were taking place in France. The first one was the Paris-Rouen Railway
in 1843 followed by Le Havre-Rouen and Dieppe legs (1847) also Cherbourg-
Mantes and Le Mans and more.
The contractor was Thomas Brassey ,a Cheshire man born at Buerton near
Chester who also had Bulkeley Hall (near Peckforton) as his home and works in
Birkenhead. He was a major contractor who with countless Navvies ,Masons &
Suppliers etc of all nationalities built major parts of the Railway network in
Britain and France not to mention many other contracts world wide including the
Canadian Grand Trunk with its Victoria Btidge over the St Lawrence..
I refer you to a book you may obtain through library service called "Life
and Labours of Mr Brassey" by Arthur Helps first published 1872 later editions
available.There is a chapter devoted to the early France contracts and
detailing a viaduct near Rouen that collapsed.
Everyone knows of the engineers Stevenson ,Brunel etc , but the contractors
were the main body of builders. Not a Mobile telephone,Car or Computer
between them.
I have no idea how you check any possible connection but I offer it as a
strong possibility and reason you might find ancestors in this area of France
around this time.
Ron B. (another Cheshire Railway man)