From this memorandum we make the following entry in the Dimension Book, dividing the square of each diameter by 289, (the circular divisor for MashTun Gallons,) and thus obtaining the Gallons. These, divided by 8, become Bushels; and bushels, divided by 8, give Quarters.

DIMENSION BOOK.

A. B.'s Round Mash-Tun Gaged, 10 May, 1820.

The area, for an inch deep, in Quarters, Bushels, and Gallons, having been now ascertained for each of the diameters taken, we are to construct a Table of the Tun, in which the content for any assigned depth may be seen by inspection.

To do this, we have only to add the area for the first inch at the bottom, continually to itself, till the sum contains the first area 10 times; then to the content thus found at 10 inches deep, we are to add, in like manner, the area for an inch of the second division, 10 times also: and so of all the rest except the last, which, since the

uppermost division of the Tun consists of no more than

5 inches, must be added only 5 times.

In the course of the operation it will be of advantage to check the result at the end of every division of the Tun, as this will, in case of error, prevent a great deal of trouble.

The practical mode of checking the process of tabling has been fully explained, and elucidated by an example in PROBLEM I., as will be seen on referring to page 237. The only difference is, that in Coppers the areas are subtracted from the top for dry inches, but in Tuns added from the bottom for wet inches.

A. B.'s ROUND MASH-TUN TABLED.

As the Goods in a Mash Tun are not of a nature to assume a surface perfectly level, but on the contrary have, for the most part, the surface very uneven, no account of drip needs be taken, since a mean depth, from several dips, is invariably to be considered the depth of the Goods.

PROBLEM V.

To Gage and Inch a Square Mash-Tun.

At the middle of every ten inches from the bottom,

take the breadth of the Tun half way between the middle of the side and each of the ends: and at the same time take the length on the same level, half way between the middle of the end and each of the sides.

Thus, if ABCD were a horizontal section of a square Mash-Tun, five inches from the bottom, the two breadths would be mn, vx; and the two lengths would be rs, wz.

Then half the sum of mn and vr would be the mean breadth of the Tun five inches from the bottom; and half the sum of rs and wz would be the mean length on the same level.

Precisely in this way the mean breadth and mean length at 15 inches, 25 inches, 35 inches, &c. from the bottom will be obtained from two breadths and two lengths respectively at those altitudes. If any inches and tenths remain at the mouth, above the last division of ten inches, two breadths, and two lengths are to be taken at half the altitude of this smaller division from the mouth.