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stiffened on the streets. Ships, barges, and boats were sunk by the floating ice in the Thames. Those who could, confined themselves to their houses for fear of being frozen, but the fishermen, bricklayers, gardeners, and workmen generally assembled in hundreds and marched through the streets begging for food and clothing. In 1762 it snowed in England' for eighteen days in succession. A succession of severe winters occurred toward the close of the century. Of these, that of 1784-85 was the most severe. In England the first snowfall was on October 7, 1784, and out of the one hundred and seventy-seven days that followed until April 2, there were but twelve during which it did not freeze or snow. During the winters of 1788, '94, and '98 nearly all the principal rivers of Europe were frozen-the Thames, Seine, Rhone, Elbe, and the Rhine being amongst the number. The winter of 1788–89 was marked by the extent and violence of its snowfalls, which traversed all Europe and caused great loss of life. February, 1799, was memorable for its great snow-storms, extending throughout the midland and eastern counties of England. The winter of 1812 will ever be remembered as that in which Napoleon's Grand Army" retreated from Moscow amidst blinding snows, through overwhelming snow-drifts and intense cold, the soldiers falling by thousands on the way. These snowfalls also extended to England. In many parts of England the year 1814 was long known as that of the “great frost.” Snow lay four feet deep in the streets of many of the towns, and country roads were absolutely impassable. The winter of 1820 also was remarkable for heavy snows, but that of 1836, so far as Great Britain was concerned, was marked by the worst snowstorm of the preceding one hundred years. After snowing heavily for two days in December, the wind increased on the night of the 26th to a hurricane, and by the morning from four to nine feet of snow had fallen, while in places drifts rose to heights varying from twenty to fifty feet. “ The mails, all business, and correspondence were stopped nearly a week, until the multitudes employed had cut a way in the snow." In 1842 there were again heavy snowfalls and drifts in England, and mail. coaches were completely buried. One night's snowfall was sufficient to bury the coach, and it took, in one instance, seventy men, working all night, to cut a way through the drift and allow it to proceed on its journey. Another severe winter in Great Britain was that of 1866–67. Many trains were snowed up on northern railroads. In the United States and Canada we have, as a matter of course,

had great years of snowfall and extensive blockades of trains and general travel, but I can find no connected history of these extending from early dates to the present time. Those of most recent date were the winters of 1875–76, 1879–80, and 1880-81. During the winter first mentioned, as all of us well remember, a tremendous snow-blockade of trains occurred throughout the Northern and Western United States. A letter at that time thus referred to the almost unprecedented snowfall: " It is estimated that between Boston and the West—Chicago, etc.there have been at least ten thousand tons of merchandise blocked up at various points. On one single line alone more than sixty miles of freight-cars have been standing still, waiting for the snow to thaw. Between Buffalo and New York eight thousand goods-cars have been shunted off on to the sidings, the main lines being impassable through the snow.

In Vermont, New Hampshire, and Maine the snow has been over sixteen feet deep, while Washington legislators have had to proceed to political engagements through two feet of snow. This unusual experience in the city named has been nearly equalled by deep falls of snow in several of the Southern States.” A very similar blockade of snow occurred again in pretty much the same sections of country during the winter of 1880-81.

HAIL AND HAILSTONES.

The immense magnitude of some hailstones, and the intensity of cold during the hottest period of summer requisite to freeze these in their descent to the earth, have never been satisfactorily accounted for. An explanation offered is, that they must have been originally formed at an altitude in the atmosphere where the temperature is greatly below 32°, and that, in consequence of their extreme coldness, they acquired magnitude during their descent by condensing on their respective surfaces the vapors contained in the electrified cloud and atmosphere through which they passed. The difficulty, however, is not altogether obviated by this conjectural explanation. In this country hail-storms seldom assume any remarkable appearance, but in some other countries, especially in the southern districts of France between the Alps and the Pyrenees, hailstorms are so violent, and the hailstones so large, as frequently to lay waste large districts of country. Of late years some very disastrous hailstorms have occurred in portions of the Western United States and West.ern Ontario. These storms have invariably been accompanied with thunder and a violent squall or whirlwind. Individual hailstones have been known to weigh as much as five ounces, but there are stories in existence of much heavier ones. These large particles of ice are seldom globular, but rather of an irregular and angular shape. Hail-storms generally occur during the hottest period of the year, and seldom during night or winter.

EARTHQUAKES.

The most notable and disastrous earthquakes on record, it may be said, were those of Italy (526), when 120,000 persons perished, and of Sicily (1693), when 60,000 lost their lives. According to Gibbon, toward 542 each year was marked with the repetition of earthquakes of such duration that Constantinople was shaken above forty days of such extent that the shock was communicated to the whole surface of the empire. At Antioch a quarter of a million persons are said to have perished. This period of earthquake and plague (542-547) was the period when the superior planets were in perihelion, as they are now. Arabian and Persian chronicles record one hundred and eleven earthquakes between the seventh and eighteenth centuries, some lasting from forty to seventy days, and nearly always accompanied by winds or floods or terrible storms of lightning and thunder. Readers of the Relations des Jésuites will remember the great earthquakes of 1663, which shook and tossed the earth for six months from Gaspe to Montreal, the rival of our own earthquake of 1811 in the Mississippi Valley. The severest of the earthquakes that fell in this region was that of November, 1755, an echo of the convulsion that tumbled down Lisbon-and saved the Pompay ministry, through the fact that the minister's house was almost the only one left uninjured and his family one of the few not bereaved of a member. Hein, in his interesting work on earthquakes, estimates that on an average two earthquakes a day occur on the earth. In 1870, though there was no severe single shock, 2225 houses were destroyed or greatly damaged in Italy, 98 persons killed and 223 wounded. The same shock may last for years; instance that of Viege, in the Valais, which endured from July, 1855, to 1857. At Cabul thirty-three severe shocks have been felt in one day; at Honduras, in 1856, one hundred and eight were counted in a week; and at Hawaii, in 1868, two thousand shocks occurred in one month. Hein, it may be said in conclusion, opposes the theory of a connection between earthquakes and volcanic eruptions, and considers that of their coincidence with atmospheric phenomena as better supported by facts; for they are occasionally preceded or accompanied by thick and widespread fogs at seasons when fogs are not frequent, by sudden falls of the barometer, and by equally sudden changes of temperature. Their occurrence, however, in the majority of cases, coincides with normal meteorological conditions. Earthquakes are more frequent after sunset than in daytime, in autumn and winter than in spring. The influence of the moon is insignificant.

THE COURSE OF STORMS.

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In weather-charts which embrace any considerable portion of the earth's surface two different systems of pressure are recognized. One system or set of systems is that of low pressure, which is marked off by concentric isobarics, or lines enclosing pressures successively lower as the centre space is approached; the other set of systems is that of high pressure, which is marked off by roughly concentric isobarics, enclosing pressures successively higher as the central space is approached. The areas of low pressure are generally found to be smaller in extent than those of high or average pressure, and the areas of high and low succeed each other after the same manner as the wave rolls along the ocean, ever on the point of emptying itself into the trough of the sea; which, however, constantly recedes as the crested, towering wave rapidly advances. Thus a storm one day may be found central in the Mississippi Valley, and in twenty-four hours will have whirled its way to the Connecticut, and in another twenty-four to St. John's, Newfoundland, advancing at the rate of thirty-six miles an hour, preceded and followed by areas of high pres

A storm is simply an advancing whirlwind, the wind blowing in circuits of greater or lesser extent from east to west, or in a contrary direction to the hands of a clock, around an axis, and is caused by the constant struggle of the atmosphere to maintain an equilibrium of pres

The general progress of storms is north-eastward, their origin usually being in the Far West, beyond the stations of the most westerly American observers; but some commence in the United States and Canada. When a storm begins in any district where observations are taken, it is noticeable that the line of minimum pressure does not come from the Far West, but commences with the storm and travels with it eastward. From the above observations it is evident that the direction of the storm-centre may be obtained by standing with the back to the wind, when the lowest barometer or centre of depression will be to the left in the northern hemisphere, and to the right in the southern : this rule holds universally. After the storm has begun it will increase until the barometer has reached its lowest reading, when a temporary lull occurs—the calm before the storm- --and the clouds break and there are signs of clearing. But soon the western part of the oval reaches the observer, bringing more rain, while the winds are from the opposite quarter; the barometer rises rapidly, the temperature falls, and there is clearing weather.

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ATMOSPHERIC CONDITIONS DURING CYCLONES.

REVERTING to the terrible cyclones in Iowa, Nebraska, Kansas, and Missouri on Sunday, June 12, an illustration of the general atmospheric conditions in that region on that day may be of interest :

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Here we find an intelligible illustration of the fact that opposing cur. rents of air strongly contrasted in temperature, encountering each other, establish a rotary movement from their collision, attended by the formation of hail, the induction of violent winds, and the precipitation of frequently torrential rain.

These disturbances are not, properly speaking, cyclones; they are merely local tempests, more or less violent, of cyclonic character, and the probability of their occurrence can only be predicted in a general way from the general weather conditions. In the illustration we find decided contrasts in temperature and opposing winds. The arrow (2) probably indicates the direction of the line of meeting. The arrow (1) points to a then existing area of low pressure, the region illustrated being in its south-east quadrant. The observations were made at 2.30 P. M., Cincinnati time. The despatches referring to North-eastern Missouri say

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