Croydon's pneumatic railway

I had some time to kill in Croydon the other day, and went into Croydon Musuem, which contains artefacts and exhibits spanning the last couple of hundred years of Croydon's history.  One interesting technological exhibit is a pipe from Croydon's atmospheric railway. Rather than pull (or push) the train carriages by a locomotive engine, an atmospheric railway uses a pipe which is partially evacuated to suck the train along using pneumatic force.  Some atmospheric railways feature large pipes inside which the whole carriage is placed.  This is the design of the hyperloop system being developed in the USA right now, and was used for non-passenger mail-rail systems in London in the past.  Croydon's used a smaller pipe in which a slug, attached to the carriage, is propelled.  The railway in Croydon never worked very well, as mentioned in the exhibit, pictured here, and the line was converted to a conventional rail line with locomotive engines used on it.