The Imperial gallon was based on the volume of 10 lb. of distilled water weighed in air with brass weights with the barometer standing at 30 inches of mercury and at a temperature of 62 °F. In 1963, this definition was refined as the space occupied by 10 lb of distilled water of density 0.998 859 g/mL weighed in air of density 0.001 217 g/mL against weights of density 8.136 g/mL. This works out at approximately 4.546 090 3 L (277.441 6 in³).
Also known as:
- Gallon
