Those tubes were what you were supposed to use in the Ever Ready metal torches in the 20's and 30's - using loose cells makes for a really bad rattle and flickering. In my three cell light I use a solid one piece holder that takes 12AA batteries (two stacks of 6 in parallel, 4 across) with a charge socket in the base and so I run 6 Volt lamps. Using Eneloop rechargeable cells gives about 8 hours of white light.
Just finished restoring a 'bullseye' lamp - all contacts were so open circuit that it would have passed a 3kV flash test! All fixed and down to under 0.2 Ohms, new 3.5V, 0.3 A bulb and 8AA battery holder fitted, along with regulator. Run time of undimming light is 30 Hours! The regulator will run the 8AA's down to almost complete exhaustion without yellowing.
It is light oak, but looks darker in the photo.
https://www.dropbox.com/s/kuyq9xpco1...33931.jpg?dl=0
and the beam
https://www.dropbox.com/s/c03oefusan...33823.jpg?dl=0