“I have,” he says, “long held the proper inquiry to be, what are storms? and not, how are storms produced? as has been well expressed by another. It is only when the former of these inquiries has been solved that we can enter advantageously upon the latter.”
The former does not seem to be yet solved, or the solution of the latter commenced. Mr. Redfield tells us (page 259, and onward), that there is an extended stratum of stratus-cloud, which overlies the storm, and that it does not differ greatly from one mile in height. We are not told how the air, which finds its way to a higher elevation during several days continuance of such a storm, gets through the stratum. If he is right it must do so, and it would not answer to suppose a very small opening or gentle current through it, to carry off all the air which works inward in a hurricane, during several days continuance. But he does not seem to recognize either the necessity or existence of any vent at all; nor is there any; and this fact is open to the observation of every school-boy in the country; and it is equally open to his observation that when and where the barometer is most depressed, the stratus storm-cloud is nearest the earth. Colonel Reid has much to say about the “storm’s eye,” or “treacherous center” of a storm. A careful analysis of the instances where the “storm’s eye” is noticed will show that the term is applied, in the northern hemisphere, to that lighting up in the W. or N. W., which is the commencement of the clearing-off process, and attended with a shift of wind to the fair-weather quarter: i. e., to W. or N. W. Just such an “eye” as is seen when the last of the storm cloud has passed so far to the east as to admit the rays of the sun under the western or north-western edge of it. The same kind of “storm’s eye” is described in the southern hemisphere, except that the wind shifts to S. W. instead of N. W., that being the clearing-off wind there. No instance of a “storm’s eye” in the center of the extended stratum of stratus-cloud, which overlies the storm, can be found recorded, to my knowledge; and it is obvious that Colonel Reid adopts the view of Mr. Redfield, that the westerly and N. W. fair weather winds are a part of the storm. So long as these gentlemen hold to that opinion they will never solve the question, “what are storms?” or reach the other, “how are storms produced?”
Notwithstanding, Mr. Redfield asserts, or adopts the assertion, that the inquiry should be, “What are storms?” not “How are storms produced?” that inquiry should be a rational one, and should not violate all analogy, or call for an explanation which science can not rationally furnish. Mr. Redfield does not seem to have formed any just conception of the immeasurable power of a hurricane, five hundred miles in diameter; or of the nature of that rod which the Almighty must insert in it, to whirl it with such violent and long-continued force; nor any just conception of the tendency of the whirling mass, in the absence of his “cylindrical vessel,” to fly off, tangentially, into the surrounding air; or of the nature or power of the centripetal force necessary to hold the gyratory mass in its current, and gather it in involute spirals toward a center. Nor has any other man who has witnessed, or read of mountain-tossed waves; of the largest ships blown down and engulfed; of towns submerged, and vessels carried far inland, and left in cultivated fields, by the subsidence of the sea; of sturdy forests and strongly-built edifices prostrated; or listened to the howling of the tempest, and felt his own house rock beneath him, been able to conceive of any known form of calorific or mechanical, or other power, acting from a comparatively small center, which could hold such an immense irresistable mass of whirling air in a circle, and gather it in toward the center in gradually contracting spirals. I confess that, to my mind, it seems little less than a mockery of our intelligence for Mr. Redfield, or Professor Dove, or any other man, how distinguished soever he may be, to tell us that all this is the result of a “tendency to left-wise rotation” of ordinary winds, “coming into each other,” or “over-sliding,” or “meeting,” or “encountering,” on this “front,” or that, down in Central America, or in the West Indies, or the monsoon region; or to talk of “lateral overflows” from mere gravity; of the ascent of warm air, or the descent of cold strata; of the resistance of adjacent passive air, or other mere atmospheric resistances in connection with such awful manifestations of power. Their explanations of these phenomena are not rational, nor can they be believed by any rational man, who will bestow upon them half an hour of comprehensive, unbiased reflection.
Waiving many minor points of great force, for this notice of Mr. Redfield’s theory is already too much extended for my limits, I am constrained to take issue with him on the fact, and to assert, unhesitatingly, that in a majority of instances no such barometric curve exists.
Doubtless the depression beneath the storm is found, and exterior lateral elevations may also be had by extending the line into the usual fair weather elevation on each side, as Mr. Redfield is obliged to do, to get his supposed circle of winds at all. Doubtless, too, the seamen sailing out of a storm, on either side, and approaching fair weather, will have a rising barometer. But from front to rear, on the line of progression, in tropical storms, the curve does not exist on shore, in this latitude, oftener than in two, or possibly three, cases in ten; and then only upon a single state of facts—that is, when there is an interposition of N. W. wind; and this, at some seasons, rarely occurs. An elevation usually occurs before the storm, on its front, if it present an extensive easterly front, as one of these classes does, and a depression is left after it has passed off, unless a considerable body of N. W. wind interposes, as heretofore stated. But when there is not such interposition of N. W. wind (for W., W. N. W., or even N. W. by W. will not suffice), there is not an immediate rise of the barometer corresponding in rapidity and extent with the fall, and frequently none during the first twenty-four hours of bright, fair weather. Let the reader, if he has access to a barometer, note this fact, for it is obvious and conclusive.
Finally, there are other atmospheric conditions to which the barometric changes are obviously due:
1st. The counter-trade is of a different volume, at different times, over the same locality, and hence a difference in the normal elevations of the barometer.
2d. It is at a different elevation, at different times, over the same locality. It was so found by the investigations of the Kew Observatory Committee referred to; has been so found by other aeronauts, and may readily be seen by a careful, practiced observer.
It is highest, with a high barometer, in serene weather, when a storm is not at hand; and can sometimes be plainly seen to ascend when a considerable volume of N. W. wind is blowing in beneath, and elevating, simultaneously, the trade and the barometer.
Opportunities occur every year, when the northern edge of the dissolving stratus-cloud is attenuated, and the storm is clearing off in the N. W., with wind from that quarter, and a rising barometer, when its gradual elevation may be observed to correspond with the volume of that wind.