"5. The front ends (leeward to the storm) of two brick stores owned by Eli Montgomery, were thrown outward with great force, the windward ends being uninjured.

"6. Another large brick house, near the last just mentioned, owned by Watt, Burke & Co., had the leeward side nearly demolished.

"7. Another brick house adjoining the last mentioned, had the windward gable end thrown outward.

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"8. The Theatre, a large brick building, had the entire roof blown off and thrown some ten feet forward, and the walls demol ished.

"9. The leeward walls of two front rooms of the Tremont House on Wall street, were thrown outward with great force, without destroying or moving the furniture therein, and where the storm could have no access.

"10. The roof of the fire-proof brick office of the Probate Court, exploded to windward, that side, it is presumed, being the weakest.

"11. The gable ends of a large brick store on Main and Pearl streets, were thrown outward with great force.

"12. The southern side, and the northern and western gable ends of the brick Insurance buildings on Pearl and Market streets, were thrown outward with such force as to nearly demolish the building.

"13. The roof of Dr. Merrill's house on State street was saved by the explosive power bursting open a large trap door in the roof, thereby making an outlet for the expanded air.

"14. The leeward wall of a new wooden house owned by Rhasa Parker, on Washington street, was thrown outward by the explosive power, the windward side end remaining unbroken excepting the glass of the windows."

Professor Johnson in his description of the New Brunswick tornado, which occurred on the 19th of June, 1835, has called attention to the same curious fact. He says: "In a few cases, in which the ridge of a building lay in a northerly and southerly position, the eastern slope of roof was ob served to be removed, or at least stripped of its shingles, while the western slope remained entire. Many buildings were likewise observed with holes in their roofs, whether shingled or tiled, but otherwise not much damaged, unless by the demolition of windows. These appearances clearly demonstrated the strong upward tendency of the forces by which they were pro duced, while the half unroofed houses, already mentioned, prove that the resultant of all the forces in action at the moment was not in a perpendicu lar to the horizon, but inclined to the east. Such a force would apply to the western slope of the roof some counteracting tendency, or relieve it from some portion of the upward pressure. Had there been no other facts to show the powerful rushing of currents upward, the above would, it is conceived, have been sufficient to settle the question, but taken in connection with the circumstance that roofs so removed, were carried to a great height, and their fragments distributed over a large extent along the subsequent path of the storm, that beds and other furniture were taken out of the upper stories of unroofed houses, that persons were lifted from their feet or dashed upward against walls; and that in one instance, a lad of eight or nine years old, was carried upward and onward with the wind, a distance of several hundred yards; and particularly that he afterward descended in safety, being prevented from a violent fall by the upward forces, within the range of which he still continued. In connection with

these and similar facts, it seems impossible to doubt that the greatest violence of action was in an upward and easterly direction.”

If these surprising results, which have been long the subject of observation, are so easily accounted for on the principles laid down by Mr. Espy, so, also, are all the other phenomena of these wonderful storms. We often hear of sticks, grass, sand, &c., frozen in the hail which falls from one of these clouds, and the curious fact has given rise to much speculation. The solution is now, however, perfectly simple. The current of ascending air which dashes with such fearful velocity upward into the cloud, and carries with it these lighter substances from below, also carries up the water which has been condensed from the saturated air, and throwing all out together at the side of the cloud in the region of congelation, they are frozen together in the form of hail, and descend by their own gravity to the earth. Large sheets of water may also be thrown out and frozen in the same way, which, breaking in their fall, will account for the great hail stones and "pieces of ice" spoken of by Howard, which fell at Salisbury, and for the "pieces of ice" of almost every form which fell during the passage of the Orkney spout in 1818.

Again: it is not uncommon for rain and hail to fall from one of these clouds in two distinct veins. Mrs. Tillinghast of Providence, during the passage of the tornado of 1838, saw two showers descending from the cloud, both of which sloped inward towards the spout which hung from the centre of the cloud below; and M. Pouillet has given an account of a hail storm which travelled from the Pyrenees to the Baltic, in 1788, leaving two veins of hail about fifteen miles apart, in which space there was a great rain. The eastern vein was about seven miles in width; the western about twelve, and on the outside of both was also a strip of rain. This storm progressed at the rate of about fifty miles per hour; the hail fell in no one place for more than eight minutes: the largest of them weighed eight ounces. We copy the chart of this storm below, as it appeared in the memoirs of the French Acadamy. A. A. A. are veins of rain; B. B. are veins of hail.-(For Chart, see next page.)

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Mr. Espy, in his remarks on these singular phenomena, says: "If I had made this storm myself, it would be said that I had made it to illustrate my theory. For it is manifest that the outspreading of the air above, will, in many cases, carry with it the hailstones; and those which are least the farthest, and these smaller hailstones on the outside of the bands, will melt before they reach the earth, while the larger hailstones, falling more swiftly, and having more ice to melt, may reach the earth in the form of hail. Thus the two veins of hail, and the rain on the outside of them, are manifestly accounted for; it is not quite so plain why it should only rain. in the middle. Nevertheless, if we consider that the vortex moved with a velocity of fifty miles an hour from the southwest to the northeast, we will readily perceive that, as it would require perhaps twenty or thirty minutes for the drops of rain to be carried up to their greatest elevation, and to fall down to the earth, during which time the upmoving column would move forward twenty or twenty-five miles, neither hail nor rain could appear in front of the vortex, and as it could not fall in the middle of the spout, being prevented by the force of the ascending air, whatever fell between the two bands of hail must have descended in the hinder part of the ascending column, where it would not be likely to descend, on account of its upper part leaning forward."

These lofty clouds, whether formed over land or water, when the dew point is very near to the temperature of the air, appear to let down from their bases a tongue of vapor in the form of an inverted cone, which has been called a spout. Mr. Espy, in his explanation of this phenomenon, says: If, however, the air is very hot below, with a high dew point, and no cross currents of air above to a great height, then, when an upmoving current is once formed, it will go on and increase in violence as it acquires perpendicular elevation, especially after the cloud begins to form. At first the base of the cloud will be flat; but after the cloud becomes of great perpendicular diameter, and the barometer begins to fall considerably, as it will do from the specific levity of the air in the cloud, then the air will not have to rise so far as it did at the moment when the cloud began to form, before it reaches high enough to form cloud from the

cold of diminished pressure. The cloud will now be convex below, and its parts will be seen spreading outwards in all directions, especially on that side towards which the upper current is moving, assuming something of the shape of a mushroom. In the mean time, the action of the in-moving current below, and upmoving current in the middle, will become very violent, and if the barometer falls two inches under the centre of the cloud, the air, on coming in under the cloud, will cool by diminished pressure about ten degrees, and the base of the cloud will reach the earth, if the dew point was only eight degrees below the temperature of the air at the time the cloud began to form. The shape of the lower part of the cloud will now be that of an inverted cone with its apex on the ground, and when a little more prolonged and fully developed, it will be what is called a tornado if it is on land, and a water-spout if at sea."

Mr. Espy observes that there is a tendency in one of these clouds to form another, and the second has a tendency to form a third, and so on, till a number are in operation at the same time. The cause of this he very happily explains, but our limits will not allow us to follow him. Lieut. Ogden gives an account of seven of these spouts seen at one time, in the edge of the Gulf Stream, in May, 1820, which we copy, together

with the annexed cut,

He says: "The atmosphere was filled with low, ashy-colored clouds, some of which were darker underneath than others, and from these the water-spouts were generally formed, each one from a sepa. rate cloud. In some instances, they were perfectly formed before we observed them, but, in others, we could see a small portion of the cloud, at first extend downward, in the shape of an inverted cone, and then continue to descend, not very rapidly, until it reached the water. In other instances, however, we observed that this conical appearance of a portion

of the cloud did not always result in the perfect formation of a waterspout. Several times we saw the cone project, continue for a short time stationary, then rise again slowly, and disappear in the clouds. This would, in some cases, occur two or three times to the same cloud; but, eventually, a larger and darker cloud would descend, and result in form. ing the visible spout, as above mentioned."

It will be seen at a glance, that the principle on which Mr. Espy explains the phenomena of nature in the production and development of storms, requires the convergence of the winds towards a common centre or line at the base of the cloud. In this he differs materially from Mr. Redfield, who has been at great pains to show that all storms are whirlwinds, and that the air moves around from right to left, or contrary to the hands of a watch. On this point there is still much controversy, but we have no room to enter on the merits of the discussion in this article, and shall content ourselves with exhibiting some of the facts on which Mr. Espy relies to establish this, one of the main pillars of his theory.

As the violent action which attends tornadoes is generally confined to very narrow limits, these storms seem to furnish the best means for testing the truth of these, different theories. It is, we think, clear that if the wind moves around a common axis in the form of a whirl, that the trees which are thrown down on the borders of the storm should lie parallel to its path, while those which fall in the centre should be left in a transverse position, or at least be thrown outwards and forwards on one side, and outwards and backwards on the other. Now it would seem from a great variety of testimony that the trees in these violent storms are not prostrated in the above named direction.

President Bache, of Girard College, after having carefully taken the direction in which the trees fell in the New Brunswick tornado with a

mariners' compass, says :-" I think it entirely made out, that there was a rush of air in all directions at the surface of the ground towards the mov ing meteor; this rush of air carrying objects with it. The effects all indicate a moving column of rarefied air, without any whirling motion at or near the surface of the earth."

Professor Loomis,* of the Western Reserve College, after drawing a map of the trees and buildings which fell in a hurricane that passed over Stowe in Ohio, comes to a similar conclusion. "It will," he says, "then appear from an inspection of the diagram, that in the midst of some dis order there was a degree of uniformity. Thus upon either border of the track the trees all incline towards some point in the centre of the track. There is not an example of a tree being turned outwards from the track, nor even one which lies in a direction parallel to it." He afterward adds,-"We have now established, by a fair deduction, that there was a powerful current of air from the opposite sides of the track towards some point in the centre of the track, and that here there was also a powerful current upward.”

Professor Olmsted,† of Yale College, in his account of the New Haven tornado, which occurred on the 31st of July, 1839, says: "The first great fact that strikes us, is, that all the trees and other objects that mark the direction of the wind which prostrated them, are, with a very few ex

• Professor Loomis is not an advocate of Mr. Espy's theory. + Professor Olmsted is not a believer in Mr. Espy's theory.