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the Atlantic Ocean and in Europe these rains of dust have almost invariably fallen between January and April, a period of the year in which the Sahara is most arid.

Fine dust falling on vessels in the Atlantic near the Cape de Verde Islands has often been reported, but it has so often been of a reddish hue that it is known among sailors as "red fog," and has been generally supposed to come from South America. The observation on board the Berean appears to overthrow this conclusion, and to determine the African origin of both the Atlantic dust and the so-called "blood rains" of Southern Europe.

One of the most remarkable of the paradoxical storms swept down on the German steamer Argentine in the summer of 1889. It lasted for four days, during which time the air was so full of dust particles as to make high noon-day almost as dark as the darkest midnight. When the "storm" was at its height the sailors were kept busy shovelling the dust from the steamer's decks. The machinery was made to work with great difficulty, and at one time the captain had grave apprehensions that they would be dashed upon the Cape Verde reefs.

Storm of Ashes.-The steamer St. Paul, from San Francisco to Alaska, entered into a dense black cloud at ten o'clock one morning, from which it did not emerge until two o'clock in the afternoon. Judged by the speed of the ship and the velocity of the dust storm, the volcanic cloud was probably 100 miles long. Showers of fine volcanic dust fell upon the deck to the depth of several inches. At noon it was so dark that lamps had to be lighted, and the sunshine was as pale as moonlight. The nearest active volcano was in the Pabloff Mountains, 265 miles away.

Showers of Fish.-Perhaps the strangest of all storms are those where there have been showers of fish, rats, toads, lizards, reptiles and the like, which have been recorded from time to time, like the shower of fish quite recently noted in Western Colorado. About 1828, at the island of Islay, it rained herrings off and on for several hours. A similar rain of another sort of fish occurred near Allahabad, India, in 1840. In 1804, a great shower of frogs fell near Toulouse, France. There is nothing

miraculous in these occurrences. The wind scoops up these animate objects, as in its less powerful manifestations it carries aloft leaves and dust and other light substances, and scatters them wheresoever it will. There is a case on record in Norway where a colony of rats, while migrating from the high to the low countries, was caught up by the wind, borne through the air and de posited in a neighboring valley.

WATERSPOUTS.

A waterspout is a remarkable meteorological phenomenon, of the nature of a tornado or whirlwind, usually observed over the sea, but sometimes over the land. Sir J. F. W. Herschel says: "Tall columns, apparently of cloud, and reaching from the sea to the clouds, are seen moving along, often several at once, sometimes straight and vertical, at others inclined and tortuous, but always in rapid rotation. At their bases, the sea is violently agitated, and heaped up with a leaping or boiling motion, water, at least in some cases, being actually carried up in considerable quantity, and scattered round from a great height, as solid bodies are by tornadoes on land."

There are numerous instances where those on vessels have sighted waterspouts. Perhaps one of the most remarkable of recent instances was that on the occasion reported by Captain McKay, of the ship Kelat, from Chittagong, India, to New York. The Kelat was in latitude 25° north and longitude 65° west. A fresh breeze was blowing and the sky was overcast. Suddenly a waterspout made its appearance, whirling along about half a mile away from the ship and extending from the clouds. to the water. Then another and another waterspout appeared, until there were twelve of these watery pillars whirling over the surface of the sea. Most of them were small and nearly all of them at least half a mile away from the ship. There were two of the largest nearer the ship-one on either hand-and their tops spread out until they formed an arch, through which the Kelat sailed. Captain McKay did not think at any time that the ship was in danger from the waterspouts, as they did not approach near enough to the vessel.

THE TYPHOON.

The worst storms are the typhoons of the Chinese seas. They cover a large area, are uncertain in their movements and follow each other quickly. In the exact center of a typhoon the sea is calm and the winds are hushed. Around it on all sides the winds are blowing in different directions at once, and the moment a ship passes out of the calm it is impossible to tell from which quarter the dangerous squall may swoop down and strike her. The central calm is often 20 square miles in extent. It is caused by the rotary motion of the winds, and the sky is usually clear directly over it. During the typhoon season the storms follow each other quickly, and there are often several at once raging in different parts of the far East. During August and September, in fact, the season is at its height.

MIRAGE.

A mirage is an optical illusion arising from an unequal refraction in the lower strata of the atmosphere, and causing remote objects to be seen double, as if reflected in a mirror, or to appear as if suspended in the air. It is frequently seen in deserts, as well as on the sea, presenting the appearance of water. The steamer El Norte, of the Morgan Line, reported a most remarkable mirage off Hatteras. In a smooth sea, with the sun shining, the "counterfeit presentment" of about twenty-eight schooners was seen, outlined against a bank of fog, lying to the westward.

A mirage in the Caribbean Sea was the cause of the loss of the American barkentine Steadfast. When the Steadfast sighted the lofty peaks of St. Croix, the atmosphere assumed a peculiar light color, and it became impossible to detect the sky from the island, everything assuming a similar shade and color, resembling the cir rostratus clouds, and hiding the entire lower portion of the island, the mountain appearing to be twenty miles away. The mountain's tops seemed to be inverted, the tall cocoanuts appearing to grow from the sky to the earth. The sugar grinding mills were pouring their

smoke downward, and the workmen working upside down. The vessel crashed over the reefs and was soon fast on the rocky shore, before Nature's deception was discovered.

The finest sea mirage is the Fata Morgana, in the Straits of Messina, between Calabria and Italy, where the strata of heated air gives rise to the appearance of objects at a distance as inverted, distorted, displaced or multiplied.

OLD OCEAN.

LAND AND WATER OF THE GLOBE.

It is estimated by Mr. John Murray, a member of the Challenger expedition, and one of the highest authorities on oceanography, that the area of the dry land of the globe is 55,000,000 square miles, and the area of the ocean 137,200,000 square miles. He estimates the volume of the dry land above the level of the sea at 23,450,000 cubic miles, and the volume of the waters of the ocean at 323,800,000 cubic miles. He fixes the mean height of the land above the sea at 2,250 feet, and the mean depth of the whole ocean at 12,480 feet. Of course these results are only approximate, but they help to render our ideas of these matters more definite. He also estimates that the rivers of the world would carry into the ocean every year 2 cubic miles of sediment. To this must be added the matter carried to the sea in solution, which is estimated at 1.183 cubic miles of matter. Together, then, the amount of matter carried through the land each year is 3.7 cubic miles. It would thus, according to this calculation, take 6,340,000 years to transport the whole of the solid land down to the sea.

The areas of the several oceans are estimated by one authority, as follows: Pacific, 70,000,000 square miles; Atlantic, 35,000,000 square miles; Indian, 25,000,000

square miles; Antarctic, 8,500,000 square miles; Arctic, 4,500,000 square miles.

The seas are in length about as follows: Mediterranean, 2,000 miles; Caribbean, 1,800 miles; China, 1,700; Red, 1,400; Japan, 1,000; Black, 932; Caspian, 640; Baltic, 600; Okhotosk, 600; White, 450; Aral, 250.

The entire coast-line of the globe is about 130,000 miles.

The Gulf of Mexico is the largest gulf, 800,000 square miles.

THE AIR OF THE SEA.

The air of the sea taken at a great distance from land, or even on the shore and in ports when the wind blows from the open, is in an almost perfect state of purity. Near continents the land winds drive before them an atmosphere always impure, but at 100 kilometers (62.135 miles) from the coasts this impurity has disappeared. The sea rapidly purifies the pestilential atmosphere of continents; hence every expanse of water of a certain breadth becomes an absolute obstacle to the propagation of epidemics. Marine atmospheres driven upon land purify sensibly the air of the regions which they traverse; this purification can be recognized as far as Paris.

THE ATLANTIC.

The name Atlantic comes through the Latin from the adjectival prefix in the Greek name for the Atlantic Ocean, which means the sea beyond Mt. Atlas. The Atlantic has an area according to one authority, of 24,536,000 square miles. The surface of the Atlantic would form a circle 6,180 miles in diameter, between onesixth and one-seventh of the total area of the earth's surface. Its average depth is more than the height of Mt. Blanc. It has 80,000,000 cubic miles of water, could be contained in the Pacific bodily nearly three times, and a sphere would have to be 533.5 miles in diameter in order to hold it. The number of cubic feet of water in it is expressed by 117 followed by 17 ciphers. It

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