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tidal waves. The tornado which is of common occurrence in regions east of the Rocky Mountains and sometimes in the Southern States, is a small cyclonic storm-that is, a storm with a very limited area of low pressure, but of extraordinary violence and intensity. Tor

STEAMER Mary, ONE OF THE LARGE BOATS TOSSED OUT OF THE WATER AT MOBILE.

nadoes occur during the spring and summer months-occasionally in the winter in the South-and while they are usually limited as to duration and the extent of country traversed, they are more numerous, and more destructive than tropical hurricanes, and therefore are more to be dreaded. A hurricane, on the other hand, may be of such vast proportions that the area of low barometer will vary in diameter from a hundred to several hundred miles in extent-or even a thousand miles-and it may traverse the continent from the Caribbean Sea to Nova Scotia.

There is something grandly terrible in the aspect of nature at the approach of one of these death-dealing storms, for they usually give their warnings several days in advance. First a long swell on the ocean is noticeable, for the wave force is transmitted to a great distance. There is a faint rise in the barometer preceding the gradual fall. Even the sky changes its appearance and wisps of cirrus clouds are observed; the air is hot and sultry, but in time a gentle breeze begins, which steadily increases until it reaches gale force. But the hurricane has not arrived. The clouds now become matted, the sea black and rough, the rain begins to fall and the winds become gusty; when the vortex of the storm is almost at hand the tempest breaks in indescribable fury, dark

ness comes on, the rain descends in blinding torrents, and vivid flashes of lightning add to the terror of the scene. Then the air suddenly grows cooler, and in the midst of the awful din and uproar, as the forces of nature battle with each other, there is a sudden pause; the sky clears and the winds almost cease. The vortex is upon us-it is "the eye of the storm," for the barometric pressure is at its lowest. The brief respite is portentous, awful; there is a strange light in the sky and the ocean surges in mountain swells; then, as the vortex moves forward in its path, the destructive forces renew their violence, but with the wind in the opposite direction. The carnival of death may continue an hour-a night-but the storm center has passed, and the morning sun rises upon a scene of ruin and devastation.

As there are localities where earthquakes are prevalent, so there are regions where tropical hurricanes are of periodic occurrence, though the larger part of the earth's surface is free from their unwelcome visitations. They have been of

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CHAOTIC MASS OF WRECKAGE LEFT BEHIND BY THE HURRICANE AT PENSACOLA, FLA.

gulfs with numerous islands in the vast sea to the eastward. In the opinion of Father Viñes, the distinguished meteorologist of Havana, who has comprehensively studied cyclonic movements in the West Indies for many years, of all cyclonic regions within the intertropical zone, the Great Bay of North America, with the wide Atlantic Ocean extending to the east as far as the coast of Africa, and northwesterly to Europe and the northern seas, more perfectly and grandly combines all requisite conditions for such storms. In his opinion there is not another region on the face of the globe where cyclones are met with, which offers more favorable conditions for their development.

Hurricanes are formed in the southern portion of this Great Bay of North America, that is to say, in the Caribbean Sea, and in that portion of the Atlantic extending east of the West Indies, the precise locality of formation being influenced by the position occupied by the equatorial zone of calms, by the Atlantic area of high barometric pressure-to which the term "anticyclone" is applied -and by the southern limit of the trade winds, respectively. The point of origin and formation of the storm depends therefore upon the more or less advanced season of the year.

According to the conventional theory of the origin and formation of tropical cyclones, as recently explained in a paper on the subject by Prof. Bigelow of the Weather Bureau, these storms are more likely to occur at the season of the year when the cooling of the Northern Hemisphere takes place. At this season the belt or zone of calm in the tropics

and the heated, moist condition of the air in the region known as the "doldrums” is at its farthest northern limit. The South Atlantic permanent anticyclone, which lies over the subtropical ocean is in its fullest vigor. Superposed upon these states of the lower atmosphere, the colder temperatures of the upper atmosphere, caused by the approaching autumn, on account of the more rapid circulation higher up, overspread the tropic strata near the surface. As the polar air cools first, it flows gradually above the warmer air at the south of it near the ground, and covers it with a circulating sheet of temperature cool or low for the time of year. The effect is to make the atmosphere unstable, that is to say, too warm at the

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COMPLETE WRECK OF A BUILDING NEAR THE BEACH AT PENSACOLA.

The whirling motion of the winds in a cyclonic storm is due to the force of gravity, and the deflective force occasioned by the rotation of the earth. As the upward pressure upon the vortex of the storm or center of lowest barometric pressure, is greater at the center, the air is pushed inwards toward the region of lowest pressure, and the air

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particles follow a spiral path. The velocity and destructive energy is greatly augmented as the center is approached.

The direction of the wind movement does not follow the direction of the path. of the cyclone, this path, or track, being indicated only by the changes in atmospheric pressure, as the vortex, or point of lowest pressure moves onward in its course. The movement of the "storm center," or lowest pressure, may be so gradual that one of these storms will require a week or more to move from the point where first observed to the point of disappearance.

The wind vane at a fixed point veers continually as the vortex or center of the storm moves forward, and the wind may at one stage blow almost in an opposite direction from the course of the storm, wind direction changing according to fixed laws as the vortex moves farther away. In illustration, it may be said that in the westward course of a cyclone, the wind at the commencement will blow from a northern quarter, and during the latter part of the gale from a southern quarter. The direction of wind change always corresponds to the changes in the direction or course of the cyclone. The direction of rotation in a hurricane is always from left to right in the Northern. Hemisphere.

The wind at the time of greatest violence in a hurricane may acquire a rate of 70, 80 or even, in extreme cases, 100 miles an hour velocity, and the potential energy displayed under cyclonic conditions may reach hundreds of millions of horsepower.

The courses, or paths of many of the more destructive hurricanes which pass through the Eastern United States describe a section of an ellipse, though there are marked exceptions. The path of a hurricane may be considered as made up of three sections, the first branch, the recurve, and the second branch. As an illustration, one of these storms may, after formation, start in a northwesterly direction with little change while in the region of tropic heat and moisture, but when it strikes a cooler region, it will assume a northerly direction, and recurving, in the temperate zone, pass northeasterly and disappear in the region of New England or Nova Scotia.

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The storm which.devastated Indianola, Texas, in August, 1886, was a storm of this description. It was unable to recurve owing to the high barometric pressure to the northward. Forced westward, intense energy was developed at Indianola, after which the storm lost itself on the Eastern Slope of the Rocky Mountains.

The recurve, therefore, is dependent upon general meteorological conditions, particularly upon the distribution of atmospheric pressure. As the path of the hurricane soon carries it beyond the tropics, and into temperate regions, it assumes more and more the characteristics of a cyclone, spreading over a larger area and finally losing its energy.

In some instances, the course of a storm has been marked by loss of energy, after doing great damage in a certain locality, its violence being renewed- again, after a lull, at a point far remote. The hurricane of September 26, 1906, was such a

storm. It exerted its greatest violence in Georgia and Florida, but a second period of violence occurred in Virginia and the District of Columbia, and after a second lull it again renewed its activity in New York State. During the two days in which this storm passed over nine states, it destroyed 114 lives and seven million dollars' worth of property. In severity it was one of the worst storms of modern times.

This destructive hurricane originated in the Caribbean Sea, and moved northwest through the Yucatan Channel and across the gulf in a north-easterly direction, striking the United States coast a little west of Mobile, Sept. 26 (1906), where it developed greatest energy. It then moved northwest into the upper eastern corner of Arkansas, thence to Eastern Missouri, where it subsided. Pensacola was caught by its eastern edge, and not a house escaped damage, Fort Pickens being partially destroyed. The property losses in Louisiana, Alabama and Florida are partially estimated at

$3,000,000. Much damage was done to the railroads, 30 miles of road-bed having been washed away in one section of the Louisville & Nashville R. R. Forty-four light houses were swept into the sea or wrecked, and four keepers drowned. For the illustrations of the effects of this hurricane, I am indebted to Weather Bureau officials of Mobile and Pensacola, through the courtesy of Prof. Henry.

Through the efforts of Prof. Moore, Chief of the U. S. Weather Bureau, at the time of the Spanish war, in 1898, twenty West Indian weather stations were established, and they have been continued. These stations, in co-operation with other West Indian observers, are able to forecast accurately the approach of a storm several days before its appearance on our coast, and the Bureau is enabled to send out its warning bulletins. The forecast of the recent Mobile hurricane was given out at least 48. hours before the storm appeared, and proved to be accurate in every particular. Thus greater disasters are avoided.

Dawn

The first gray streaks of dawn but show
The world yet sadder than before,
As hill and tree and homestead grow
Wan phantoms in the morning glow.

Wait; while the cold gray here is round us,
There, rising up behind the height,
The sun, in rose-red splendors found us,

And all the world is full of light.

-London Saturday Review.

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