Hydrometry

n.	1.	The art of determining the specific gravity of liquids, and thence the strength of spirituous liquors, saline solutions, etc.
	2.	The art or operation of measuring the velocity or discharge of running water, as in rivers, etc.

Noun

1.

hydrometry - the measurement of specific gravity Synonyms: gravimetry

gravimetry, measure, measurement, measuring, mensuration