As this was nearly a central passage, and as the influence was less extensive than usual, on account of great atmospheric pressure with a low dew point, the central disturbance could the more readily be located, and was certainly to the north, and but a few miles. The following is from the record of the weather:
August 6th. Very fine and clear all day; wind from S.-W.; a light breeze; 8 P. M. frequent flashes of lightning in the northern sky; 10 P. M. a low bank of dense clouds in north, fringed with cirri, visible during the flash of the lightning; 12 P. M. same continues.
7th. Very line and clear morning; wind S.-W. moderate; noon, clouds accumulating in the northern half of the sky; wind fresher S.-W.; 3 P. M. a clap of thunder overhead, and black cumuli in west, north, and east; 4 P. M. much thunder, and scattered showers; six miles west rained very heavily; 6 P. M. the heavy clouds passing over to the south; 10 P. M. clear again in north.
August 8th. Clear all day; wind the same (S.-W.); a hazy bank visible all along on southern horizon.
This was not a storm, in the ordinary acceptation of the term; but the same cause, under other circumstances, would have produced one; and let it be borne in mind, that although the moon is the chief disturbing cause, and the passages of the vortices are the periods of greatest commotion in both settled and unsettled weather, still the sun is powerful in predisposing the circumstances, whether favorable or unfavorable; and as there is no periodic connection between the passage of a vortex and the concurrence of the great atmospheric waves, it will, of course, happen only occasionally that all the circumstances will conspire to make a storm. There are also other modifying causes, to which we have not yet alluded, which influence the storms at different seasons of the year,—exaggerating their activity in some latitudes, and diminishing it in other latitudes. In this latitude, the months of May, June, and July are marked by more energetic action than August, September, and October. The activity of one vortex also, in one place, seems to modify the activity of another vortex in another place. But the great question to decide is: Do these vortices really exist? Do they follow each other in the order indicated by the theory? Do they pass from south to north, and from north to south, at the times indicated by the theory? Do they obey, in their monthly revolutions, a mathematical law connecting them with the motions of the moon? We answer emphatically, Yes! And the non-discovery of these facts, is one of the most humiliating features of the present age.
OTTOWA STORM, DECEMBER 22, 1852.
To show that the same calculations are applicable for other times, we will make the calculation for the centre ascending, for the 22d December, 1852, taking the following elements:
| Moon’s | mer. passage, Dec. 22d | 15h. | 16m. | G. time. |
| " | right ascension, same time | 51° | 57′ | |
| " | declination north | 15° | 42′ | |
| " | true S. Diameter | 886.6″ | ||
| " | distance from node | 37° | ||
| " | ""quadrature | 52° | ||
| Which gives the arc AR | 29° | 5′ | ||
| 1st correction | −1° | 51′ | ||
| 2d" | +1° | 11′ | ||
| Corrected arc AQ | 28° | 25′ | ||
And the latitude at the time of the meridian passage = 42° north, or about forty miles north of Ottawa.
Abstract from the record:—