This is a gas leak indicator circa 1930's. The instrument comes in a brown leather stitched case, fitted with a small studded carrying strap and lined with green felt. It is in very good condition.
The instrument has a brass and copper body with gnurled/bezzled adjusting segments. It is 120mm tall and 65mm diameter. The dial reads from 0 to 90 and carries the name "Short's Gas leak indicator Abbott Birks & Co Ltd London SE1". The base carries the stamped number 7756. It carries a tag "purchased in Rye Sept 93" with a price tag of £25.
I am not an expert in this field but if you have any questions I will try to answer them.
Any collector of scientific instruments will be thrilled with this interesting piece.
Happy bidding.
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