The Atmospheric Railway was a pioneering, but ultimately unsuccessful invention, the first commercial use of it being in Ireland on a line from Kingstown (Dun Laoghaire) to Dalkey.
Whilst sometimes credited in error to Brunel, due to his adoption of the system on the South Devon Railway, the system in the form used in Ireland and Britain was that developed by Clegg and the Samuda brothers.
Further details on the Atmospheric Railway in Ireland can be found in Chapter 14 of "A Railway Archaeology of Ireland".
The system was different that the French Government sent one of their civil servants, by the name of "Mallet", over to view and report on it. Co-incidentally, the well known engineer Robert Mallet also produced a report on the Atmospheric Railway, which has given rise to the erroneous historical suggestion that Robert Mallet prepared the report for the French Government.
The report prepared for the French Government is below - clich each image to access.