Page:Physical Geography of the Sea and its Meteorology.djvu/385

Rh the unknown as it does for the known regions, the mean height of the barometer would be at the north pole about 29.6, at the south about 28 inches. These lines, N and S, represent what may be called the barometric descent of the counter-trades.

672. The "brave west winds"—their barometric descent.—The rarefaction of the air in the polar calms is, as we have seen



(§ 667), sufficient to create an indraught all around to the distance of fifty degrees of latitude from the south pole; also (§ 662) the rarefaction in the belt of equatorial calms, is sufficient