In taking the dimensions of a Cask, it must be carefully observed: 1st, That the bung-hole be in the middle of the cask; 2d, That the bung-stave, and the stave opposite to the bung-hole, are both regular and even within; 3d, That the heads of the Cask are equal, and truly circular; if so, the distance between the inside of the chime to the outside of the opposite stave will be the head diameter within the cask, very near.

Rule

Take, in inches, the inside diameters of a cask at the head and the bung, and also the length ; subtract the head-diameter from the bung-diameter, and note the difference.

If the measure of the Cask is taken outside, with callipers, from head to head, then a deduction must be made of from 1 to 2 inches for the thickness of the heads, according to the size of the Cask.

1. If the staves of the Cask, between the bung and the head, are considerably curved, (the shape of a pipe,) multiply the difference between the bung and head by .7.

2. If the staves be of a medium curve, (the shape of a molasses hogshend,) multiply the difference by .66.

3. If the staves curve very little, (less than a molasses hogshead,) multiply the difference by .6.

4. If the staves are nearly straight, (almost a cylinder,) multiply the difference by .55.

6. Add the product, in each case, to the head-diameter; the sum will be a mean diameter, and thus the Cask is reduced to a cylinder.

6. Multiply the mean diameter by itself, and then by the length, and multiply, if for Wine gallons, by 0034. The difference of dividing by 294, (the usual method,) and multiplying by .0034, (the most expeditious method,) is less than 500ths of a gallon in 100 gallons.

Example

Supposing the head-diameter of a Cask to be 24 inches, the bung-diameter 32 inches, and the length of Cask 40 inches, what is the contents in Wine gallons?