globe, and hence their relative weight, which always retains them in an equilibrium, impels them towards the opposite point to the moon. Thus in the two cases, when the moon is at the meridian of a place, or at the opposite meridian, the water must be raised nearly to the same height, and consequently fall and rise, when the moon is at the horizon either at her rising or setting. Thus a motion, such as we have just mentioned, necessarily disturbs the whole mass of the sea, and agitates it throughout its whole extent and depth; and if this motion appears insensible in the open seas, it is nevertheless no less real; but as the winds cannot ruffle the bottom in an equal degree with the surface, the motion of the tides is necessarily more regular there, although directed alternately in the same manner as at the top. From this alternative motion of flux and reflux there results, as already observed, a continual motion of the sea from east to west, because the moon, which produces the tides, proceeds from east to west, and successively acting in the same direction, the water follows her course. This motion is most considerable in all sraits; for example, at the straits of Magellan the water rises nearly 20 feet, and continues so for six hours, whereas the reflux lasts only two[C], and the water runs towards the west. This evidently proves that the reflux is not equal to the flux, and that from both there results a motion towards the west, much stronger in the time of the flux than in that of the reflux. This is the reason that in open seas, remote from land, the tides are only felt by the general motion of the waters from east to west. [C] See Narborough's Voyage. The tides are stronger in the torrid zone between the tropics than in the rest of the ocean: they are also more sensible in places which extend from east to west, in long and narrow gulphs, and on the coasts where there and isles and promontories. The greatest known flux is at one of the mouths of the river Indus, where the water rises thirty feet. It rises also very remarkably near Malays, in the straits of Sund, in the Red Sea, in Nelson's Bay, at the mouth of the river St. Lawrence, on the coasts of China, Japan, Banama, in the Gulph of Bengal, &c.