GAUGE, GAUGE ROD

Gauging is the method of determining the quantity of liquid in vessels such as barrels, casks, etc.

The exact capacity of any vessel or receptacle may be obtained by measuring the dimensions and then conducting the calculation upon geometrical principles. An approximate measurement can be obtained more easily by the average person by means of a gauge-rod suitably adjusted for the purpose. The instrument usually employed is a diagonal rod, the contents of the cask being inferred from the diagonal length, measured from the bung-hole to the extremity of the opposite stave at the head. On one face of a square rule is a scale of inches for taking the measure of the diagonal, the scale on the opposite face expressing the contents in gallons. Only approximate results are thus obtainable, yet with experience it is possible to measure the contents with sufficient accuracy to answer general requirements.