Here we have a Brush built battery loco at the Avonmouth military mustard gas factory near Bristol during WW1. Brush had ordered a very small battery loco from Siemens some time before entering into production of this type, nothing in the Siemens range from that period comes close so possibly it was to test out the electrical side.

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And here is number 7 with it's windows up plus a second loco top right...

Mine
Colin James....