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portance, it having been generally agreed, that printing was not practised till after the middle of the fifteenth century, although prints from blocks of wood are traced as far back as the year 1423.
It seems probable, that the art of printing might have been introduced into Europe by some European who had travelled into China, and had seen some of their printing tablets, as it is known that several Europeans had been overland to China before this time; and what strengthens this probability is, that the Europeans first printed on one side of the paper only, in the same manner as the Chinese do at present. But however this may be, the progress of the art was as follows:
First, pictures from blocks of wood, without text. Secondly, pictures, with text. Thirdly, whole pages of text, cut on blocks of wood : sometimes for the explanation of prints which accompanied them. And, fourthly, moveable types.
No. 6.-THE AURORA BOREALIS. THIS phenomenon is seen in its most brilliant state in high northern and soutbern latitudes. Dr. Barry thus describes the appearance of it on the coast of Orkney: “ Here,” says he, “ the northern lights happily appear, both more frequently, and with greater splendour, than in most other regions : for during the harvest, winter, and spring months, they arise almost every unclouded night, and often shine with the most magnificent brilliancy. The light of the moon at her quadratures, sometimes, on such occasions, scarcely equals them, in illuminating the friths and the islands. Between the setting of the sun and the close of the twilight, they commonly make their first appearance in the north, issuing, for the most part, from behind the clouds, like a fountain of pale light, the form of which is undefined, and continue in this state a little above the horizon, sometimes only for a short period, and at other times for the space of several hours, with
out any motion that can be discovered. They form themselves one while into an arch, the height of which is about thirty degrees, and its breadth about sixty, and the pillars on which it is supported several times broader than the rainbow; and so long as they retain this shape, they are without any sensible motion. At another time they extend further over the heavens, rise much higher, assume a greater variety of shapes, and discover a dusky hue, with a motion that is slow, but perceptible. Very often they exhibit an appearance quite different, and spread themselves over the whole heavens, diffusing every where a surprising degree of light, and exhibiting the most beautiful phenomena.
Their motion, in this case, is in various directions, extremely swift, and, as it were, in separate columns, resembling somewhat the evolutions of a great army: Their lowest extremities are distinctly defined, and deeply tinged with the colours of the rainbow; but their upper ones are tapering, but fainter. In several places, at once, they kindle into a blaze, dart along in almost all directions, for some seconds of time, and then, as if by the strength of their exertions they had spent their force, they are extinguished in a moment, leaving a brown track in the sky behind them. Neai the place where they disappeared, in a short time, they flash out anew, and with equal rapidity trace the same path in similar motions, and again expire in the same manner. This they often continue for several hours together, to the great satisfaction and amusement of the spectators on land, and the advantage of the mariner, when they gradually die away, and leave through the whole heavens a colour resembling that of brass. If the night be uncommonly still, and their motion very rapid, a wbizzing noise has been thought to have been distinctly heard from them at various intervals. This beautiful corruscation, which has never yet been satisfactorily explained, is said to have appeared much seldomer eighty or ninety years ago than it does at present. It appears now, however, very often, and seems to occupy that space in the heavens which is between tbe region of the clouds and the summit of the atmosphere, as the clouds in motion never fail to eclipse it, and as it cannot be seen from two places
greatly distant from one another at once, nor yet in conjunction with the same fixed stars, it evidently has no great degree of elevation.
THE NEW GEYZER.* ON the visit of Mr. Hooker to this spring, in the summer of 1810, for the space of an hour and a half an uninterrupted column of water was continually spouted out to the elevation of one hundred and fifty feet, with but little variation, and in a body of seventeen feet in its widest diameter; and this was thrown up with such force and rapidity, that the column continued to nearly the very summit as compact in body, and as regular in width and shape, as when it first issued from the pipe: a few feet only of the upper part breaking into spray, which was forced by a light wind on one side, so as to fall upon the ground at the distance of some paces from the aperture. The breeze also, at times, carried the immense volumes of steam that accompanied the eruption, to one side of the column of water, which was thus left open to full view, and we could clearly see its base, partly surrounded by foam, eaused by the columu striking against a projecting piece of rock, near the mouth of the water; but, thence to the upper part, nothing broke the regularly perpendicular line of the sides of the water-spout, and the sun shining upon it, rendered it in some points of view of a dazzling brightness. Standing with our backs to the sun, and looking into the mouth of the pipe, we enjoyed the sight of a most brilliant assemblage of all the colours of the rainbow, caused by the decomposition of the solar rays passing through the shower of drops that was falling between us and the crater. After the water had risen to the vast height above described, I ventured to stand in the midst of the thickest of the shower of spray, where I remained till my clothes were all wetted through, but still scarcely felt that the water was warmer than my own temperature. On the other side of the spout the co
* For another account of this extraordinary phenomenon, see the Pocket Magazine, vol. i. p. 197.
lumn was so undivided, that though upon the very brink of the crater, within a few inches of the water, I was neither wetted, nor had I a fear of being scalded by any falling drops. Stones, of the largest size that I could find, and great masses of the silicious rock, which we threw into the crater, were instantly ejected by the force of the water; and though the latter were of so solid a nature, as to require very hard blows from a large hammer when I wanted to procure specimens, they were, nevertheless, by the violence of the explosion shivered into small pieces, and carried up with amazing rapidity to the height of, and frequently higher than the summit of the spout. One piece, of a light porous stone, was cast at least twice as high as the water, and falling in the direction of the column, was met by it, and a second time forced up to a great height in the air.
EARTHQUAKE IN CANADA.
ON the 5th of February, 1663, about half an hour past four in the evening, a great noise was heard, nearly at the same time, throughout the whole extent of Canada. That noise seems to have been the effect of a sudden vibration of the air, agitated in all directions. It appeared as if the houses were on fire, and the inhabitants, in order to avoid its effects, immediately ran out of doors. But this astonishment was increased when they saw the buildings shaken with the greatest violence, and the roofs disposed to fall, sometimes on one side, sometimes on the other. The doors opened of themselves, and shut again, with a great crash. All the bells were sounding. The pallisades of the fences seemed to bound out of their places, the walls were rent, the planks of the floor separated, and again sprung together. The dog's answered these previous tokens of a general disorder of nature by lamentable howlings; the other animals sent forth the most terrific groans and cries, and, by a natural instinct, extended their legs to prevent themselves from falling: The surface of the earth was moved like an agitated sea; the trees were thrown against each other, and many, torn up by the roots, were tossed to a considerable distance.
Sounds of every description were then heard, at one time, like the fury of a sea which had overflown its barriers; at another, like a multitude of carriages rolling over a pavement; and, again, like the mountains of rock" or marble opening their bowels, and breaking into pieces with a tremendous roar. l'hick clouds of dust, which at the same time arose, were taken for smoke, and for the symptoms of an universal conflagration. The
consternation became so general, that not only men, but the animals, appeared as if struck with thunder; they ran in every quarter, without a knowledge of their course, and wherever they went they encountered the danger which they wished to avoid. The cries of children, the lamentations of women, the alternate successions of fire and darkness in the atmosphere, all combined to aggravate the evils of a dire calamity.
The ice which covered the St. Laurence, and the other rivers, broke into pieces, which crashed against each other; large bodies of ice were thrown into the air, and from the place they had quitted, a quantity of sand, and slime, and water spouted up. 'The sources of several springs and little rivers became dry: the waters of others were impregnated with sulphur. At times the waters appeared red, at others of a yellowish cast; those of the St. Laurence became white from Quebec to Tadoussac, a space of thirty leagues. The quantity of matter necessary to impregnate so vast a body of water must have been prodigious. In the mean time the atmosphere continued to exhibit the most awful phenomena : an incessant rushing noise was heard, and the fires assumed every species of form. Porpoises and sea-cows were heard howling in the water at Three Rivers, where none of these fishes had ever before been found, and the noise which they sent forth resembled not that of any known animal.
Over the whole extent of three hundred leagues from east to west, and one hundred and fifty from north to south, the earth, the rivers, and the coasts of the ocean,