dasymeter

plural dasymeters

1. datedAn instrument for testing the density of gases, consisting of a thin glass globe, which is weighed in the gas or gases, and then in an atmosphere of known density.

   Spring-balances are in use in numerous early forms of so-called dynamometers, dasymeters, etc., in machines used for testing paper, textile fabrics, wire, etc., as in the apparatus of Hartig-Reusch, Wendler, Martens.

   1899, Adolf Martens, Handbook of testing materials

   2 more examples

   The dasymeter consists of a two-armed lever or balance beam, on one arm of which is a hermetically sealed glass sphere of 3 litres capacity, while the other arm carries a balancing weight. The higher the percentage of carbonic anhydride contained in the gas to be examined, the higher will be its specific gravity, and consequently the greater its weight.

   1894, The Journal of the Iron and Steel Institute, volume 44, page 340

   With the idea that regulation of air supply would secure great economy of fuel, an instrument called a “dasymeter” has been invented to indicate the percentage of carbonic acid in the products of combustion; the weight of a vessel, through which gases are being continually drawn from the chimney of a boiler, is indicated on a scale which shows the percentage of carbonic acid compared with the weight of pure air.

   1896, The Sibley Journal of Engineering, volume 10, page 116