+----------+-------------+ | Fathoms. | Temperature.| +----------+-------------+ | | ° | | Surface. | 77·9 | | 10 | 77·2 | | 20 | 77·1 | | 30 | 76·9 | | 40 | 71·7 | | 50 | 64·0 | | 60 | 60·4 | | 70 | 59·4 | | 80 | 58·0 | | 90 | 58·0 | | 100 | 55·6 | | 150 | 51·0 | | 200 | 46·6 | | 300 | 42·2 | | 400 | 40·3 | | 500 | 38·9 | | 600 | 39·2 | | 700 | 39·0 | | 800 | 39·1 | | 900 | 38·2 | | 1000 | 36·9 | | 1100 | 37·6 | | 1200 | 36·7 | | 1300 | 35·8 | | 1400 | 36·4 | | 1500 | 36·1 | | Bottom. | 34·7 | +----------+-------------+ We have in this Table data for determining the height at which the surface of the ocean at the equator ought to stand above that of the poles. Assuming 32°F. to be the temperature of the ocean at the poles from the surface to the bottom and the foregoing to be the rate at which the temperature of the ocean at the equator decreases from the surface downwards, and then calculating according to Muncke’s Table of the expansion of sea-water, we have only 4 feet 6 inches as the height to which the level of the ocean at the equator ought to stand above that at the poles in order that the ocean may be in static equilibrium. In other words, the equatorial column requires to be only 4 feet 6 inches higher than the polar in order that the two may balance each other.