Coriolis žowmeters were developed in the 1970s to Ÿll the need for a žowmeter that measures mass directly, as opposed to those that only measure velocity or volume. Because they are independent of changing žuid parameters, Coriolis meters have found wide application. Many velocity and volumetric meters are a¥ected by changes in žuid pressure, temperature, viscosity, and density. Coriolis meters, on the other hand, are virtually una¥ected by these types of changes. By measuring mass directly as it passes through the meter, Coriolis meters make a highly accurate measurement that is virtually independent of changing process conditions. As a result, Coriolis meters can be used on a variety of process žuids without recalibration and without compensating for parameters speciŸc to a particular type of žuid. Coriolis žowmeters are named a£er Gaspard G. Coriolis (1792-1843), a French civil engineer and physicist for whom the Coriolis force is named.