Page:Physical Geography of the Sea and its Meteorology.djvu/395

Rh graphic method of engraved squares for a farther discussion of these figures, it appears by the subjoined Diagram B, that in February the north-east and south-west winds are in equal conflict between the parallels of 20° and 22°; that in March the former have been "backed down" (§ 684) as far as the parallel of 16°-15°—the medial line between them from which each  monsoon is blowing—and where, again, the conflict of "back to back" is equally divided as to time of mastery (12 days) on:  either side. By the month of June they (the south-west) have fairly gained the ascendancy, and so remain masters of the field until October, when the bi-annual conflict is again commenced at the north. The vanquished north-east trades now lead off in the attack, and, as the Diagram C shows, the two combatants have force enough about the parallel of 15° north to blow during this month 9 days each. The conflict, instead of being "back to back," is now face to face; instead of blowing away from the medial line, they blow towards it; instead of being a place of high, the medial line is now (§ 657) a place of low barometer. By November the north-east monsoon has pushed the place of equal contest as far down as the parallel of 5° north.