|≈||approximately equal to|
|digits||indicates that digits repeat infinitely (e.g. 8.294 369 corresponds to 8.294 369 369 369 369 …)|
The butt was a measure of liquid volume equalling two hogsheads. This equated to 108 imperial gallons (490 l) for ale or 126 imperial gallons (570 l) for wine (also known as a pipe).
The cubic decametre (in British English and international spelling as used by the International Bureau of Weights and Measures) or cubic decameter (in American English) is the unit of volume. Its SI symbol is dam3. It is the volume of a cube with edges one decametre in length.