Although not marked, this one is believed to be an early HASAG 61 or the same model sold through another agency. It's another that is no longer with me, having found a better home a long way away.
A grand old lamp! The link below shows the 1925/26 Pifco catalogue and that model of lamp or it's twin is shown there. https://classicpressurelamps.com/threads/1925-26-pifco-catalogue.2589/
@JEFF JOHNSON Hi Jeff, Yes, there is a possibility it was a Pifco marketed lamp. The valve wheel is different on all the catalogue images I've seen, Pifco and HASAG, on this lamp the wheel axis is vertical, catalogues all show horizontal. I have to say that the vertical axis is a pain to use because of proximity of the knob to very hot brass, which makes me think it might be an early design that was changed later to improve accessibility. There is no way that the axis could be changed on the lamp in the photos, it's built into the frame.
