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METEOROLOGY.

4. Remarkable Coldness of the late Spring.-The cold and backward spring which we have had in this country has been the subject of general remark. Dr Forster, who has lately returned from the Continent, has made a corresponding remark abroad. The crops, and particularly the garden productions and flowers, have been nearly a fortnight later than usual, almost all over Germany and the northern parts of France. At Spa, the season was so cold and unpleasant that most of the visitants had left it to travel elsewhere, till there were some signs of summer; and there was ice on the water near Liege on the morning of the 8th of June. The thermometer during the day did not rise higher than 58° of Fahrenheit; and a cold dry wind seemed to threaten a total destruction of vegetation. Paris, however, we understand, was comparatively warm, and the climate seemed to change for the better on passing Arras into France.-Annals of Philosophy, Sept. 1829.

5. Changes of Climate at Shiraz.-Since the last earthquake, the climate of Shiraz has very much changed from its former salubrity. The water in the wells has risen very near the surface. Where formerly there were ten and fifteen yards of line, there are now only three or four; therefore the increased evaporation has, it is supposed, been the cause of a deleterious atmosphere in the plain.-Alexander's Travels, p. 125.

6. Effects of the Aurora Borealis on the Magnetic Needle.When I first observed the luminous appearances of Tuesday, August 28th, at 10 P. M., I placed a horizontal needle, delicately mounted, in the window of my room, which was in the northern side of the house, and a dipping-needle about ten feet distant in another window. On examination, I found that neither would come to a state of rest. The mean of the extremes, in the horizontal needle, was at least 5° west of the magnetic meridian. After marking the extremes on a paper card, fixed in the window for the purpose, I left it. The dipping-needle, which oscillated from 64° to 75°, was in constant agitation, and very irregular in its motions; sometimes rising to nearly 60°, and remaining for a moment with a tremulous motion, and then sinking back to 75° or 76°, having a mean dip of 69°, which

is, I believe, according to the best needles I have seen, 21° above the true dip of this latitude. The greatest variation of the needles was at 10 P. M., when I first placed them in the window, and it constantly decreased. The brilliancy of the aurora increased till 10 o'clock 30 minutes, when its luminousness had entirely disappeared; though there was a bright aurora in the northern horizon. On examining the horizontal needle, I found it constantly in a tremulous motion, though it did not oscillate more than 2°, or perhaps somewhat less. On setting it to oscillating, however, a second time, it came to rest at 71°; the same was repeated with the same result, viz. 71°; whereas its ordinary dip is 72°. The luminous appearances of the 29th and 31st were less brilliant; and though I examined the needles to see if any effect was produced, nothing remarkable appeared during the aurora, except that the needles were seemingly a little longer than ordinary in coming to rest.-Silliman's Journal, New York, 21st April 1828.

7. A Storm in the Mediterranean accompanied with Castor and Pollux Lights.-On Friday the green shores of Sicily came in view, but the breeze was light, and we advanced slowly. On Saturday it left us altogether, and, when I turned in at night, the sea was smooth and bright as a mirror; the vast firmament seemed to descend below us; the ship appeared suspended in the centre of an immense sphere, and, if I may say so, one felt in awe and silence the majesty of space. About midnight I succeeded by a sud

was awaked by a heavy swing of my coat, den dash to the other side: the water was pouring into our room, and I could hear it rush across the upper decks, where all was noise and rapid motion. I hurried on my clothes, and ran up. The gun-deck was clear; hammocks had already been lashed up and stowed; it was lighted up, and the lamps shewed it flooded in its whole extent. I ascended to the next. The rain came down in torrents, but I did not feel it, so deeply absorbing was the scene. The sky was in a constant blaze: the sea was not high, but the waves were broken, confused and foaming, and taking from the lightning an unnatural hue. Above me were the yards covered with human beings, thrown by each flash into strong outline, struggling hard to secure the canvas, and to maintain their precarious footing. The ship rolled tre

mendously. And now, add the wild uproar of the elements, "the noise of many waters," the deep and constant roar of the winds, the cries of men aloft, the heavy and rapid tread of those below, the reiterated orders of officers, and the sounds of the trumpet rising above all; and then, add to this the heavy rolling of thunder, at times drowning all these sounds. The first lieutenant had the deck; he had sprung to it at the first alarm, and seizing the trumpet had called for Black, his favourite helmsman. The ship was soon under snug sail, and now dashed forwards at a furious rate, giving to the gale a yet wilder character. All at once a rocky island seemed to start up from the waters-but the next broad flash shewed a good offing, and we were safe; when suddenly came a loud shout from the forecastle, "A sail on the starboard bow," and then another, "A sail close on the larboard bow." I trembled then, not for ourselves, for we should have gone over them, and have scarcely felt the shock,-but for the poor wretches, whom it would have been impossible to save. The helm was put hard down; we shot by, and I again breathed freely, when some one bade me look up to our spars. I did so, and found every upper yard-arm and mast-head tipped with lightning. Each blaze was twice as large as that of a candle, and thus we flew on with the elements of destruction playing above our heads.— In about thirty minutes, the wind, which was from the southwest, changed suddenly to the south-east, and became as hot as air from the mouth of an oven. It was the Sirocco, and brought with it a quantity of fine sand. It lasted half an hour, and was a stiff, smacking breeze, but not near so strong as the one it had succeeded. A similar electric phenomenon occurred to the ship in which Castor and Pollux sailed, in the Argonautic expedition, only the light appeared on the caps of the two heroes: the storm subsided, and they were received as patrons of sailors. In this way, too, they often appeared to the Roman armies, and were supposed to be leading them to victory. This was nothing more than the electric fluid on their spears. The late Mr Whitney of Newhaven, when riding on horseback, near East Rock, in the vicinity of that town, during a night thunder-storm of great severity, was astonished to find, all at once, his horse's ears tipped with fire. He alighted, but

now discovered the same phenomenon at the end of his whip, stirrups, and every prominent object. His own person and that of an attendant were tipped in the same manner. Similar appearances, probably, suggested to Virgil the fiction of the flame about the head of Ascanius, the night on which Troy was burnt. -Silliman's Journal.

CHEMISTRY.

8. Thorine, a new Earth.-M. Berzelius has lately discovered a new earth, possessing all the properties of that which bore the name of Thorine, and which was only a phosphate of yttria. On account of this great similarity, he retains the name of Thorine for the new substance. It is white, and incapable of being reduced by charcoal and potassium. After being strongly calcined, it is no longer attacked by acids, excepting by concentrated sulphuric acid. Even after being treated by the caustic alkalies, the sulphate of thorine is very soluble in cold water, but nearly insoluble in boiling water, so that it cannot be freed from several other salts by washing the mixture with boiling water. Thorine dissolves very well in carbonate of ammonia. Elevation of temperature determines the precipitation of a part of the earth; but on cooling the precipitate disappears. All the salts of thorine have a very pure astringent taste, almost like that of tannin. The chloride of thorine treated by potassium, decomposes with a triple deflagration. There results a grey metallic powder, which does not decompose in water, but which above a red heat burns with a brightness which nearly equals that of phosphorus in oxygen. Thorine is feebly attacked by sulphuric acid or nitric acid. Hydrochloric acid, on the contrary, dissolves it with a keen effervescence. The oxide of thorine contains 11.8 per cent. of oxygen. Its specific gravity is 9.4.

Thorine exists in a new mineral which has been found in very small quantities at Brevig, in Norway.

MINERALOGY.

9. Notice respecting the presence of Websterite in the Plastic Clay of Auteuil, near Paris; by M. BRONGNIART.-The author commences his notice with some reflections on a remarkable phenómenon which the geological history of a great number of mine

ral substances, and in particular of Websterite, presents, that of the repetition of the same geognostical circumstances in deposites which are considered as being of the same formation, although situated at considerable distances from each other, even in those which are feebly and irregularly developed, as the deposite of the plastic clay. He then mentions all that is known of the mineralogical history of Websterite, and shews that the three varieties as yet known, those of Halle, Newhaven, and Epernay, agree in the two classes of characters which essentially constitute the mineral species, the composition and form, and in their geological relations; for they always occur in veins or nodules in the plastic clay, accompanied with gypsum and lignite, and lying above the chalk. It is also in the plastic clay of Auteuil, but in the upper part of the deposite, where the clay is yellowish and sandy, that the new variety occurs, rather in nodules than in veins. It is composed of a multitude of small rounded grains, closely compacted, although not to such a degree as not to leave interstices filled with greyish clay. These nodules present internally the appearance of an oolite, with very close white grains in a greyish paste or cement. M. Dumas's chemical analysis leaves no doubt respecting the true nature of this mineral. He found it formed of 23 parts of sulphuric acid, 30 of alumina, and 47 of water. It is therefore a variety of Websterite, to which the name of oolitic may be given.-Annales des Sciences Naturelles.

10. Talc and Mica.-Von Kobell, on examining, by means of polarized light, a specimen of large foliated chlorite, from Greiner, in the Zillerthal, found that it exhibited the coloured rings with the black cross, and consequently belongs to the rhombohedral system. He also examined some newly discovered varieties of talc from Greiner, and of lithion mica from Zinnwald and Elba, and found them all have the double axis..

11. Native Sulphuric Acid.-M. Egidi, apothecary at Ascoli, observed a violent disengagement of sulphuretted hydrogen in a spacious natural cave of the commune of Acquasanta. This gas, in contact with atmospheric air, gradually decomposes, gives rise to water, and to sulphur, which latter is deposited on the walls of the cave, and quickly forms, with the salifiable bases, sulphites, and subsequently sulphates, principally crystallized sulphate of lime; and, lastly, to sulphuric

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