P.M. Tamson Dasymeter
A P.M. Tamson Dasymeter or baroscop to measure the Buoyancy of Air or the weight of air. A small balance supporting a glass bulb and a small weight on two sides of an arm. When placed in a evacuated bell jar the glass bulb appears heavier due to its greater loss of buoyancy.
The balance arises from a black painted steel stand a painted label says it was made by ‘P.M. Tamson instrumenten Den Haag’. This instrument maker was founded in 1878 by mrs. Tamson under her husbands name as a wholesaler in tools and educational equipment in the field of chemistry and physics. Nowadays, Tamson specializes in laboratory equipment. A similar dasymeter is included in the Max Kohl catalogue of 1912 and therefor this dasymeter can be dated about that age.
Dimensions: 9,5 cm x 13,5 cm x 5 cm.