It is on this account, combined with other auxiliary causes, that the vicinity of Cape Horn is so proverbially stormy, as well as for the low standard of the barometer in that latitude, it is the stationary point of the vortices in ordinary positions of the nodes and perigee of the moon. We have already alluded to the fact, that none of the vortices scarcely ever pass much beyond latitude 80°, and then only under favorable circumstances, so that we ought to infer, that gales in high latitudes should set from the poles towards the storms in lower latitudes. This is, no doubt, the fact, but, nevertheless, a hard southerly blow may possibly occur in high northern latitudes, if a storm should be raging very violently in a lower latitude on the opposite side of the pole, the distance across the circle of 80° being only about 1,400 miles. As the different vortices have a different limit in latitude every year, the determination of this turning point is obviously of great practical utility, as the fact may yet be connected with other phenomena, so as to give us the probable character of the polar ice at any assigned time. On this point we have more to say.
PASSAGES OF ALL THE VORTICES.
Our remarks have hitherto been confined to the central vortex. We shall now show from the record, that the other vortices are as effective in deranging the equilibrium of our atmosphere. In the following table we have given the passages of the different vortices, which will serve as their true positions within moderate limits, to calculate from, for all future time.
| Order. | Vortex. | Date. | Meridian Passage. | Passage. | Calculated latitude and Remarks. | ||
|---|---|---|---|---|---|---|---|
| 1st | I. A. | June | 22 | 7 | A. M. | south | Centre. About 40°. |
| 23 | 8 | A. M. | north | Warsaw. Storm. | |||
| 2d | O. D. | 27 | 0 | noon | north | ||
| 28 | 1 | A. M. | south | See record. | |||
| 3d | C. A. | July | 1 | 9 | A. M. | south | |
| 2 | 10 | A. M. | north | Lat. 43°. Storm. | |||
| 4th | I. D. | 7 | 5 | P. M. | north | ||
| 8 | 6 | P. M. | south | Lat. New York. Storm. | |||
| 5th | C. D. | 12 | 5 | P. M. | north | Aurora. | |
| 13 | 6 | P. M. | south | Stormy, very. | |||
| 6th | O. A. | 14 | 10 | A. M. | south | ||
| 15 | 11 | A. M. | north | See Record. | |||
The intervals between the ascending and descending passages of the different vortices, are
| Between | I. A. | and | I. D. | from | 11 | to | 14 | days. |
| " | O. A. | " | O. D. | " | 10 | " | 12 | " |
| " | C. A. | " | C. D. | " | 9 | " | 11 | " |
and the effect is greatest when the vortex comes to the meridian before the sun, and least when after the sun; in which case the full effect is not developed, sometimes until the following day.
A brief abstract from a journal of the weather for one sidereal period of the moon, in 1853.
June 21st. Fine clear morning (S. fresh)[15]: noon very warm 88°; 4 P. M. plumous cirri in south; ends clear.
22d. Hazy morning (S. very fresh) arch of cirrus in west; 2 P. M., black in W.-N.-W.; 3 P. M., overcast and rainy; 4 P. M., a heavy gust from south; 4.30 P. M., blowing furiously (S. by W.); 5 P. M., tremendous squall, uprooting trees and scattering chimneys; 6 P. M., more moderate (W.)