Abstract: To measure the milk yield of a cow, milk is passed continuously from the milking machine into an upper chamber of a meter while releasing air from the milk; and when the milk rises to a certain high level in the upper chamber, a valve opens to effect gravity flow of milk at a predetermined rate Q from the upper to a lower chamber until the milk descends to a certain low level in the upper chamber, whereupon the valve is closed until the milk again rises to the high level. These steps are repeated until the milk flow from the cow substantially ceases, whereupon the valve opens to effect gravity flow of the milk for the last time to said low level. The total time t occupied by said gravity flows is measured, as is the amount W of milk required to fill the upper chamber to said low level; and the milk yield is calculated by adding the values Qt and W.