Densimeter consisting of a thin glass globe that is weighed in a gas to determine its density

The Collaborative International Dictionary Word definitions in The Collaborative International Dictionary
Dasymeter \Da*sym"e*ter\, n. [Gr. dasy`s rough, thick + -meter.] (Physics) An 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.

Wikipedia Word definitions in Wikipedia
A dasymeter was meant initially as a device to demonstrate the buoyant effect of gases like air; as shown in the pictures on the right. A dasymeter which allows weighing acts as a densimeter used to measure the density of gases .

Wiktionary Word definitions in Wiktionary
n. An 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.

WordNet Word definitions in WordNet
n. densimeter consisting of a thin glass globe that is weighed in a gas to determine its density