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mulated clouds. The mountain continued to vomit lava and a dense smoke, which even at a distance was strongly sulphu. reous; the hollow noise in the sides of the mountain continued to increase. Curious to witness as near as possible one of the most astonishing phenomena of nature, and forgetting the misfortune of Pliny, I sat out from Naples, and at eight in the evening I reached Portici. From thence to the summit of the mountain, the road is long and difficult. About half way there is a hermitage, which has long served for refuge and shelter to the traveller; a good hermit has there fixed his residence, and takes care to furnish for a moderate sum, refreshments, which to the fatigued traveller are worth their weight in gold. The en. virons of this hermitage produce the famous wine called Lachry. ma Christi. From the hermitage to the foot of the cave, there is a long quarter of a league of road, tolerably good; but in order to reach from thence the crater, it is necessary to climb a mountain of cinders, where at every step you sink up to the mid-leg. It took my companions, myself, and our guides, two hours to make this ascent; and it was already midnight when we reached the crater. The fire of the Volcano served us for a torch; the noise had totally ceased for two hours; the flame had also considerably. decreased : these circumstances augmented our security, and supplied us with the necessary confidence in traversing such, dangerous ground. We approached as near as the heat would permit, and we set fire to the sticks of our guides in the laya, which slowly ran through the hollows of the crater. The surface of this inflamed inatter nearly resembles metal in a state of fusion ; but as it flows, it carries a kind of scum, which hardens as it cools, and then forms masses of scoria, which dash against each other, and roll all on fire, with noise, to the foot of the mountain. Strong fumes of sulphurick acid gas arise in abundance from these scoria, and by their caustick and penetrating qualities render respiration difficult. . We seemed to be pretty secure in this situation, and were far from thinking of retiring, when a frightful explosion, which launched into the air fragments of burning rocks to the distance of more than 100 toises, reminded us of the danger to which we were exposed. None of us hesitated a moment in embracing a retreat, and in five minutes we cleared in our descent a space of ground which we had taken two hours to climb.--We had not reached the hermitage before a noise more frightful than ever was heard ; and the volcano, in all its fury, began to launch a mass equal to some thousand cart-loads of stones, and fragments of burning rocks, with a projectile force which it would be difficult to calculate. As the projection was vertical, almost the whole of this burning mass fell back again into the mouth of the volcano, which vomited it forth anew to receive it again, with the exception of some fragments which few off, to fall at a distance, and alarm the inqui. sitive spectator, who avoided them, as on publick fêtes we avoid the handle of the rockets, in our fire-works. The 13th commenced with nearly the same appearances as those of the preceding day. The volcano was tranquil, and the lava ran slowly in the channels which it had formed during the night ; but at four in the afternoon, a frightful and continued noise, accompanied with frequent explosions, announced a new eruption ; the shocks of the volcano were so violent, that at Fort de L'Oeuf, built upon a rock, where I then was, at the distance of near four leagues, I felt oscillations similar to those produced by an earthquake. At 5 o'clock the eruption commenced, and continued during greater part of the night. This time the burning matter flowed down all the sides of the mountain, with a force hitherto unprecedented ; all Vesuvius was on fire, and the lava has caused the greatest losses ; houses and whole estates have been overwhelmed, and at this day families in tears and reduced to despair search in vain for the inheri. tance of their ancestors, buried under the destroying lava. At 10 at night, the hermitage was no longer accessible ; a river of fire had obstructed the road. The districts situated on the south-east quarter of the mountain bad still more to suffer, Mount Vesuvius was no longer any thing but one vast flame, and the seaman at a great distance might contemplate, at his teisure, this terrifick illumination of nature, &c.”

The first class of the National Institute has nominated M. Von HUMBOLDT to the place of Foreign Associate, vacant by the death of Mr. Cavendish.

i From the London Philosophical Magazine. PROCEEDINGS OF LEARNED SOCIETIES.

ROYAL SOCIETY. JUNE 28, The President in the chair. The conclusion of M. De l'Isle's paper on the poison of the bohan upas and antea was read. The emetick power of this poison suggested to the author the propriety of making some experiments with other emeticks, by injecting them into wounds and blood-vessels in the same manner as he did the upas. Ipecacuanha and tartar emetick were injected, and both produced very violent effects, particularly the latter ; but they were not so destructive to animal life as the upas. On dissecting the bodies of the ani. mals killed by injecting this poison, and comparing them with the effects of common emeticks, he was led to conclude that the upas does not kill by any specific action on the nerves, but that, by acting on the blood only, it is so instantaneously destructive to animal life.

A paper from Mr. Good was read, describing the nature of the horny concretions which appeared all over the skin of a heifer exhibited in London last year. The head, neck, and shoulders of this animal were thickly covered with little horns of various length and thickness, some of them nearly three inches long. It appears that these horns were chiefly composed of calcareous matter, and that one-fourth of them was of an animal nature.

July 5, Dr. Wollaston read a paper on a peculiar species of urinary calculus, which he called cystick oxide, only two specimens of which he has been able to procure, The cystick oxide dissolves in solutions of all the alkalies, but not in saturated carbonate of ammonia. Dr. W. also took occasion to correct some essential errours in his paper on calculi, which appeared in the Philosophical Transactions for 1797 ; subsequent experience having convinced him that phosphate of lime and phosphate of magnesia rarely or never exist together in the same calculus.

A paper on muriatick acid, by Mr. Davy, was read. The object of Mr. Davy's paper was to detail some new facts respecting the muriatick acid. Finding that charcoal, though ignited to whiteness, will not burn or decompose oxymuriatick acid gas, he was led to institute experiments to determine whether oxygen could be procured from it by any means : . VOL. X

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and the results of his inquiries are, that there is no proof whatever of its containing that substance. Muriatick acid gas inay be decomposed into oxymuriatick acid and hydrogen; and récomposed from these bodies. In all cases in which oxygen gas is procured from oxy muriatick acid gas, water is present : and the oxygen is furnished by the water; and hydrogen is always combined with the oxymuriatick acid gas ; so that, as inflammable bodies decompose water by attracting oxygen, so oxymuriatick acid decomposes it by attracting hydrogen. Mr. Davy has detailed some experiments which render it probable that the body called hyperoxymuriatick acid is in fact the simple basis of the muriatick compounds, and that it forms, oxymuriatick acid by uniting to hydrogen, and common muriatick acid gas by uniting to more hydrogen.

In attempting to decompose oxymuriatick acid gas by the combustion of phosphorus and the action of ammonia, Mr. Davy discovered a very singular compound ; which, though composed of oxymuriatick acid and ammonia with a little phosphorus, is neither fusible, volatile, nor decomposable at a white heat ; neither soluble in acid nor alkaline menstrua ; and possessed of no taste or smell.

Mr. Davy has detailed nine modes of decomposing cominon salt, founded upon these new facts, and has formed nine deductions from them respecting the composition of chemical agents, in general.

A paper on pus, by Dr. Pearson, was read.' Previously to the author's observations and experiments, a brief historical account was given of what has been already done on the subject. The conclusions among many others are : That the pus consists essentially of three different substances, viz. an opake animal'oxide, seemingly already self-coagulated ; matter ana.. logous to the coagulable lymph of the blood, but in a different state of aggregation, 2. Innumerable spherical particles, seen with the microscope, separable by chemical agents from the other parts. 3. A limpid coagulable liquid, in many properties similar to the serum of blood.) The saline impregnations are the same as those of serum of blood and expectorated matter, especially muriate of soda, neutralized potash, and the phosphates of lime. Various other substances are frequently found in pus, which are considered to be accidental, and de. pend upon different diseases.

The Society then adjourned till Thursday the 8th of No. vember..

IMPERIAL SOCIETY OF NATURAL HISTORY OF MOSCOW. M. Fischer, president of this society, has published the following short account of their labours for the last four years. This sketch is arranged under the following heads : I. Labours and Undertakings of the Society. II. Miscellanies. III. ; Promotions and Rewards. IV. Necrology. V. Literary No. velties. VI. Minutes of the Society, and Report of the Pre- . sents made to the Society and to the Museum of the Imperial University. The following are the contents of the first branch of their labours.

Journey to Siberia undertaken at the expense of the Society.-This expedition set out on the 9th of February, 1809, and is to last three years. It is composed of Professor Tauber, who is known from his description of the valley of Plauen in Saxony ; M. James Mohr, known from his travels in Germany, France, England, and Sweden ; and M. Helm, botanist and chemist, known by his description of several new plants, and by several analyses : this is his second visit to Siberia. These gentlemen are accompanied by two pupils, Messrs. Kotoroff and Leslivsky, and they are provided with every necessary, such as books, charts, instruments, and a chemical laboratory. They were to be occupied the first year with the Ouxal chain of mountains ; the second, with that of the Altai ; the third, with the mountains of the Daourie ; and, if circumstances will permit them, they will also visit Kamschatka. The profound erudition and zeal of the above gentlemen afford reason to hope for some important discoveries. They are also accompanied by a draftsman, and by a person who is acquainted with the art of stuffing and preserving animals.

Description of the Government of Moscow.-His Imperial Majesty having given five thousand roubles to be expended in examining the immense district which goes by this name, the professors of Moscow have recently visited several parts of the country with this view. The following is an account of what has been already done : Some astronomical and trigonometrical observations have been repeated at Moscow, and in some districts of the government, such as Svenigorod berea, Moja

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