392. practice of the first Part of Case the 1st.
For the Expansion with 4°, on 24 Inches; look, in the first Table, ([Sect. 363]) and in the left vertical Column, with 4 Degrees of the Thermometer; and along the upper horizontal Line, on 24 Inches of Quicksilver in the Tube of the Barometer: the Point of Meeting gives the Expansion .0097;[128] which, preparatory to Addition,
is to be placed under the 24, .178 thus,
.0097
practice of the 2d Part of Case the first.
393. In order to obtain the Expansion, with 4°, of Heat on .178 Tenths of an Inch above 24 Inches of the Barometer; let it be considered where it ought to be found in the Table: for, Tenths of 1 Inch above 24 Inches, are at some intermediate Point between 24 and 25; that is, above 24, yet not so high as 25: or more than 24, yet less than 25.
Look therefore in the Table, with 4 Degrees of Heat, on 24 Inches; then with 4° on 25 Inches: and the respective Numbers are .0097 and .0101.
And by taking the Expansion with 4° on 24 Inches, from 4° on 25; the Remainder will be the Expansion with 4° on 1 Inch above 24 Inches, viz. on the 25th Inch, thus:
| With 4° on |  | 25 = | .0101 | from; |
| 24 = | .0097 | subtract: | ||
—— | ||||
.0004 | : | |||
This therefore is the Expansion with 4°, on 1 Inch above 24 Inches.
Then with 4°, on .1 Tenth of an Inch above 24 Inches.
The Answer is the same as the former, viz. .0004, with the Addition of a Cypher and decimal Point to the left, thus; .0004 becomes .00004, viz. the Expansion with 4°, on .1 Tenth of an Inch above 24 Inches.