<Nitpick> It's a "Lucas" Lamp (named after its inventor, a Captain Lucas, and not the "Prince of Insufficient Light"), not an Aldis lamp. </Nitpick>
The WW1 versions came in wooden cases (as did the WW2 Canadian version), and there was originally a 12V 'brick' battery to power them, later replaced by the use of a made-up set of eight 'X' or 'S' cells which were standard issue for field telephones, etc. so readily available. The 'S' cells, being manufactured 'dry' could be stored indefinitely but tended to leak once filled if laid on their sides (which they had to be to fit in the battery compartment).
There should also be a similar (less tall) box with an insulating sheet in the lid that contained 16 replacement cells (two batteries worth) for replacement purposes.
Other versions: the "Mounted Services" type, in two leather cases, and the late/post WW2 "Lamp, Signalling, Daylight, Lightweight" in a canvas bag.
Then there was the 'Long Range' model powered by a 10 volt 16AH accumulator, which had a larger lamp assembly (requiring a bulb with a taller stalk to centre it in the mirror focus) and an optical sight.
Chris.