It's from a Travel Air Mystery Ship, and I was hoping someone might have seen it on another plane or even have a better detailed picture of it. I'm guessing the knob is the altitude adjust, the fir dial is tens, second is hundreds, and the top with the squares is for thousands, but that's just a guess...
Hi Kevin; Your enthusiastic response, and the info that you have been puzzling over this for years.. prompted me to go back and copy the descriptive text and details of this altimeter. Enjoy.
Most appreciated. Seems kind of a Rube Goldberg way of finding your altitude, considering standard gauges of the same era were available. I'm not really sure what the advantage would be except for mapping. Why would Frank Hawks use one when trying to set the cross country speed record?
Is that a Chevolair 6 cylinder I see on the front page of your site?