Raphael Semmes, Memoirs of Service Afloat During the War Between the States

[471] indeed, as early as the latter part of July. In these months, the sun has drawn after him, into the northern hemisphere, the south-east trade-winds of the South Atlantic. These tradewinds are now struggling with the north-east trade-winds, which prevail in these seas, for three fourths of the year, for the mastery. We have, thus, another monsoon struggle going on; and the consequence of this struggle is the cyclone. The reader may recollect the appearances of the weather, noted by me, some chapters back, when we were in these seas, in the Sumter, in July and August, of 1861; to wit, the calms, light, baffling winds, water-spouts, and heavy rains.

If the reader will pay a little attention to the diagram on page 473, it will assist him, materially, in comprehending the nature of the storm into which the Alabama had now entered. The outer circle represents the extent of the storm; the inner circle, the centre or vortex; the arrows along the inner edge of the outer circle represent the direction, or gyration of the wind, and the dotted line represents the course travelled by the storm. The figures marked, 1, 2, and 3, represent the position of the Alabama, in the different stages of the storm, as it passed over her; the arrow-heads on the figures representing the head of the ship.

If the reader, being in the northern hemisphere, will turn his face toward the sun, at his rising, and watch his course for a short time, he will observe that this course is from left to right. As the course of the arrows in the figure is from right to left, the reader observes that the gyration of the wind, in the storm, is against the course of the sun. This is an invariable law in both hemispheres; but, in the southern hemisphere, the reader will not fail to remark, that the gyration of the wind is in the opposite direction from its gyration in the northern hemisphere, for the reason, that, to an observer in the southern hemisphere the sun appears to be moving, not from left to right, but from right to left. Whilst, therefore, the storm, in the northern hemisphere, gyrates from right to left, in the southern hemisphere, it gyrates from left to right; both gyrations being against the course of the sun.

This is a curious phenomenon, which has, thus far, puzzled all the philosophers. It is a double puzzle; first, why the