Many years ago we made one of our Morgan trips to Germany, and visited the Zeppelin Museum at Friedrichshafen. In one of the display cabinets I recognised an altitude recorder that would be strung up in the 'balloon' and using a battery, heated tip, and a sort of thermal paper, would record the altitude during the flight.
I couldn't see who manufactured the recorder, but I have a similar recorder, made by Short and Mason who were based in Walthamstow until the late 50's
![[Linked Image]](https://www.tm-img.com/images/2020/09/21/Recorder2-Medium.md.jpg)
![[Linked Image]](https://www.tm-img.com/images/2020/09/21/Recorder-Medium.md.jpg)
Haven't managed to take it up high enough to see if it still works