Description: An illustration from 1891 used to explain the theory of the tides. "If the earth were uniformly covered with a layer of water, the passage of the moon over any place, as at (a), Fig. 72, it would cause the water to lose its globular form, become bulged at (a) and (b), and flattened at (c) and (d)...This deepening and shallowing of the water is caused by the attraction of the moon. As the moon passes over (a), the water is drawn toward the moon, thus deepening the water directly under the moon, and shallowing it at (c) and (d). The cause of the deepening of the water at (b) is as follows: The solid earth being, as a whole, nearer the moon than the water at (b), but farther from it than that at (a), must take a position which will be nearly midway between (a) and (b), leaving a protuberance at (b) nearly equal to that at (a). The protuberances (a) and (b) mark the positions of high tides. At all points of the earth 90° from the protuberances, as at (c) and (d) the depression is greatest. These mark the position of the low tides." — Houston, 1891, p. 76. Place Names: Moon, ISO Topic Categories: climatologyMeteorologyAtmosphere Keywords: Theory of Lunar Tides, lunar tide, water, climatologyMeteorologyAtmosphere, Unknown, 1891 Source: Edwin J. Houston, A. M. , The Elements of Physical Geography (Philadelphia, PA: Eldredge & Brother, 1891) 76 Map Credit: Courtesy the private collection of Roy Winkelman |
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