Hi there Pam,
The oracle has spoken! (i.e. son has come south for the week-end and dropped in!)
Now, the London, Tilbury and Southend Railway (LTS) was operated by the Midland Railway. The District Line had interchanges with the LTS and Midland, e.g. at Cricklewood and Richmond. At that time there were a large number of freight depots off the Underground and The Midland Railway had a number of goods depots off the District Line, e.g. Farringdon. The District Line and the Metropolitan would have been too small to have something like orphanages or other welfare services so would probably have shared in with the much bigger company, i.e. The Midland.

If you need to go further, the suggestion is either the National Railway Museum in York or Derby Local Studies library.

In case this gets back to the original query, apart from the British Railways Board not existing at that time, the term "switchman" is completely unknown in British Railway history - the guess is the same as mine, possibly a signalman?#

Have fun!