ANEMOMETER
, p. 111, col. 2, l. 1, after 12 ounces, add or 3/4 of a pound. Owing to an oversight in the succeeding lines, of considering this 12 ounces as 12 pounds, in the calculations, several errors have been incurred, and the 3d column of the table of numbers, in that page, or the column for the velocity, has the numbers only 1/4 of what they ought to be, or they require to be all multiplied by 4, the square-root of 16, the number of ounces in a pound. Hence, in line 6, for √12 r. √3/4; l. 7 and 8, for 22 4/5 r. 91 1/5; l. 8, for 15 1/2 r. 62. And the whole succeeding table corrected will be as follows:
Height of | Force of | Velocity of |
Water. | Wind. | Wind per Hour |
Inches. | Pounds. | Miles. |
0 1/4 | 1.3 | 18.0 |
0 1/2 | 2.6 | 25.6 |
1 | 5.2 | 36.0 |
2 | 10.4 | 50.8 |
3 | 15.6 | 62.0 |
4 | 20.8 | 76.0 |
5 | 26.0 | 80.4 |
6 | 31.25 | 88.0 |
7 | 36.5 | 95.2 |
8 | 41.7 | 101.6 |
9 | 46.9 | 108.0 |
10 | 52.1 | 113.6 |
11 | 57.3 | 119.2 |
12 | 62.5 | 124.0 |
In one instance Dr. Lind found that the force of the wind was such as to be equal 34 9/10 pounds, on a square foot; and this by proportion, in the foregoing table, will be found to answer to a velocity of 93 miles per hour.