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and that friendship, like the former, continued constant to the last mo. ment. When the death of his parents put gen. Villettes in posses sion of some property, he considered the friends of his family as his own friends; and the manage. ment of his pecuniary concerns was ever after intrusted to a very re. spectable gentleman, at the head of one of the first foreign houses in the city.

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The dean and chapter of West minster, at the request of the three friends above-mentioned, consented that a monument should be placed in Westminster Abbey to the me mory of this much-lamented officer. It was accordingly soon afterwards erected, and may be seen in the same chapel with the much-admired Nightingale tomb, close to the monument of the general's late frienp, the hon. sir Charles Stuart.

The inscription is as follows: "Sacred to the Memory of Lieutenant General William-Anne Villettes, Second Son of Arthur Villettes, Esq. his late Majesty's Minister Plenipotentiary at the Court of Turin, and to the Helvetic Cantons, who, during a period of thirty-three years, rendered essential service to his Country, at Toulon, in Corsica, at Malta, and in many other places.

In consideration of these Services, he was appointed Colonel of the 64th Regiment of Intantry, and Lieut.-Governor and Commander of the Forces in Jamaica; but while engaged in a Tour of Military In. spection in that Island, he was seized with a Fever, and died near

Port Antonio, on the 13th of July, 1808, aged 54 years. A worthy Member of Society was thus taken from the Public, a valuable Officer was lost to the King's Service, and the Island of Jamaica was deprived of a man well calculated to promote its Happiness and Prosperity: His residence there was indeed short, yet his manly but mild virtues, his dignified but affable deportment, and his firm but conciliating conduct, had secured him the confidence and esteem of the whole communityThe sculptureal marble shall dissolve in

dust,

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Amicitiæ Superstiti sacrum voluerunt. W.Cartwright, J. Cozenove, T. Bowdler. Westmacott sculpsit.

We shall close our remarks concerning this truly-respectable of ficer, with observing, that his two brothers having died unmarried, the male line of this very ancient family, and of course the name of Villettes, is now become extinct. The general's property, which was not very considerable, (for his liberal mind did not allow him to accumulate wealth in the very advantageous situation which he long held in Malta,) descends to his only sister, a lady who has been many years married and settled in Swis serland. The management of it

James Cozenow, esq. of Old Broad-street, London. + Miss Villettes, after her father's death, accompanied her mother to Geneva, where she was married to Albert Turettini, a gentleman of that city, by whom she had two sons, viz. Charles, who is now the only representative of the family, and

was

was intrusted to the friends of his earliest years, and his will, like every other part of his conduct through life, manifested that kind attention to all who were connected with him, from the highest to the the lowest, which was expressive of the good heart and considerate mind of the testator.

P. S. An elegant monument to the memory of the deceased general was ordered by his executors to be prepared for the island of Jamaica, as soon as the monument in West. minster Abbey was completed. Mr. Westmacott is again employed as the sculptor.

Albert, who entered into the British service, and was aid-de-camp to his late uncle in Jamaica, where he died of the same fatal fever three days after the decease of the general.

NATURAL

NATURAL HISTORY.

On some new Phenomena of Chemical Changes produced by Electricity; particularly the Decomposition of the fixed Alkalies and the Exhibition of the new Substances which constitute their Bases; and on the neral Nature of Alkaline Bodies. By Humphry Davy, Esq. Sec. R. S. M. R. I. A. [From the Transactions of the Royal Society.]

IN

N the Bakerian Lecture which I had the honour of presenting to the Royal Society last year, 1 described a number of decompositions and chemical changes produced in substances of known composition by electricity, and I ventured to conclude from the general principles on which the phe. nomena were capable of being explained, that the new methods of investigation promised to lead to a more intimate knowledge than had hitherto been obtained, concerning the true elements of bodies.

This conjecture, then sanctioned only by strong analogies, I am now happy to be able to support by some conclusive facts. In the course of a laborious experimental application of the powers of elec

tro-chemical analysis, to bodies, which have appeared simple when examined by common chemical agents, or which at least have ncver been decomposed, it has been my good fortune to obtain new and singular results.

Such of the series of experiments as are in a tolerably mature state, and capable of being arranged in a connected order, I shall detail in the following sections, particularly those which demonstrate the decomposition and composition of the fixed alkalies, and the production of the new and extraordinary bodies which constitute their bases.

In speaking of novel methods of investigation, I shall not fear to be minute. When the common means of chemical research have been employed, I shall mention only results. A historical detail of the progress of the investigation, of all the difficulties that occurred, and of the manner in which they were overcome, and of all the manipu lations employed, would far exceed the limits assigned to this lecture. It is proper to state, however, that when general facts are mentioned, they are such only as have

been

heen deduced from processes care. fully performed and often repeated.

II. On the Methods used for the Decomposition of the fixed Alkalies. The researches I had made on the decomposition of acids, and of alkaline and earthy neutral compounds, proved that the powers of electrical decomposition were proportional to the strength of the opposite electricities in the circuit, and to the conducting power and degree of concentration of the materials employed.

In the first attempts, that I made on the decomposition of the fixed. alkalies, I acted upon aqueous soJutions of potash and soda, satura. ted at common temperatures, by the highest electrical power I could command, and which was produced by a combination of Voltaic batteries belonging to the Royal Institution, containing 24 plates of copper and zinc of 12 inches square, 100 plates of 6 inches, and 150 of 4 inches square, charged with solutions of alum and nitrous acid; but in these cases, though there was a high intensity of action, the water of the solutions alone was affected, and the hydrogene and oxygene disengaged with the production of much heat and violent effervescence.

The presence of water appearing thus to prevent any decomposition, I used potash in igneous fusion. By means of a stream of oxygene gas from a gasometer applied to the flame of a spirit lamp, which was thrown on a platina spoon containing potash, this alkali was kept for some minutes in a strong red heat, and in a state of perfect fluidity. The spoon was preserved in communication with the posi

tive side of the battery of the power of 100 of 6 inches, highly charged; and the connection from the negative side was made by a platina wire.

By this arrangement some brilliant phenomena were produced. The potash appeared a conductor in a high degree, and as long as the communication was preserved, a most intense light was exhibited at the negative wire, and a column of flame, which seemed to be owing to the developement of combusti. ble matter, arose from the point of

contact.

When the order was changed, so that the platina spoon was made negative, a vivid and constant light appeared at the opposite point: there was no effect of inflammation round it; but acriform glo. bules, which inflamed in the atmosphere, rose through the potash.

The platina, as might have been expected, was considerably acted upon; and in the cases when it had been negative, in the highest degree.

The alkali was apparently dry in this experiment; and it seemed probable that the inflammable matter arose from its decomposi. tion. The residual potash was un altered; it contained indeed a number of dark grey metallic particles, but these proved to be derived from the platina.

I tried several experiments on the electrization of potash rendered fluid by heat, with the hopes of being able to collect the combusti ble matter, but without success; and I only attained my object, by employing electricity as the common agent for fusion and decom. position.

Though potash, perfectly dried

by

by ignition, is a nonconductor, yet it is rendered a conductor, by a very slight addition of moisture, which does not perceptibly destroy its aggregation; and in this state it readily fuses and decomposes by strong electrical powers,

A small piece of pure potash, which had been exposed for a few seconds to the atmosphere, so as to give conducting power to the surface, was placed upon an insulated disc of platina, connected with the negative side of the battery of the power of 250 of 6 and 4, in a state of intense activity; and a platina wire, communicating with the positive side, was brought in contact with the upper surface of the alkali. The whole appara. tus was in the open atmosphere.

Under these circumstances a vivid action was soon observed to take place. The potash began to fuse at both its points of electrization. There was a violent effervescence at the upper surface; at the lower, or negative surface, there was no liberation of elastic fluid; but small globules having a high metallic lustre, and being precisely similar in visible characters to quicksilver, appeared, some of which burat with explosion and bright flame, as soon as they were formed, and others remained, and were merely tarnished, and finally covered by a white film which formed on their surfaces.

These globules, numerous experiments soon shewed to be the substance I was in search of, and a peculiar inflammable principle the basis of potash. I found that the platina was in no way connected with the result, except as the medium for exhibiting the electrical powers of decomposition; and a

substance of the same kind was produced when pieces of copper, silver, gold, plumbago, or even charcoal were employed for com pleting the circuit.

The phenomenon was independent of the presence of air; I found that it took place when the alkali was in the vacuum of an exhausted receiver.

The substance was likewise pro duced from potash fused by means of a lamp, in glass tubes confined by mercury, and furnished with hermetically inserted platina wires by which the electrical action was transmitted. But this operation could not be carried on for any considerable time; the glass was rapidly dissolved by the action of the alkali, and this substance soon penetrated through the body of the tube.

Soda, when acted upon in the same manner as potash, exhibited an analogous result; but the de-. composition demanded greater intensity of action in the batteries, or the alkali was required to be in much thinner and smaller pieces. With the battery of 100 of 6 inches in full activity I obtained good results from pieces of potash weighing from 40 to 70 grains, and of a thickness which made the distance of the electrified metallic surfaces nearly a quarter of an inch; but with a similar power it was impossible to produce the effects of decomposition on pieces of soda of more than 15 or 20 grains in weight, and that only when the distance between the wires was about 1-8th or 1-10th of an inch.

The substance produced from potash remained fluid at the temperature of the atmosphere at the time of its production; that from

soda,

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