sing contrivances to remedy an evil which has no practical existence where the common discretion of life is exercised in obtaining the better article at an equal price.

"Had the especial purpose of the Hecla's voyage been to inquire whether the iron of a ship, in its ordinary distribution, would, under extreme circumstances, exert a sensible influence on the chronometer, better adapted arrangements could scarcely have been devised for the experiment, nor could a more decisive result in the negative have been obtained.

"The Hecla was stationary and immovable, being, frozen up, for more than ten months in the vicinity of the magnetic pole, the dip being between eighty eight and eighty nine degrees: such is the situation, and such the circumstances, which are supposed to be best adapted for the developement of magnetism in the stancheons, and other vertical iron of a ship. The chronometers were kept on board the whole winter, and their rates, preparatory to the polar navigation of the following summer, were assigned from the average of the four months immediately preceding her extrication from the ice, at an equal period of four months of navigation. The Hecla arrived at Leith, having experienced much bad weather in crossing the Atlantic but on comparing the four chronometers at the Observatory at Leith, their Greenwich time, employing the winter harbor rates, proved less than two seconds in error.

"On the arrival of the Hecla in the Thames, the chronometers were returned to Messrs. P. and F.'s house in London, when, after a month's interval, they were found to be still going at the same rate as in the Hecla whilst in the harbor of Melville Island."

Attention was first, we believe, drawn formally to the supposed alteration of the rates of chronometers on their removal on ship board by the Rev. Mr. Fisher, who found that the rates of those in his charge were uniformly accelerated under such circumstances; and he assigned as the cause, the magnetic effect of the iron, to which Captain Sabine, in the above has so pointedly adverted.

Many persons well acquainted with the subject were of opinion at the time of the publication of Mr. Fisher's memoir, that from the obvious inferiority of the chronometers which he used, no authoritative inference could be drawn from any anomalies which their rates might exhibit,-an opinion in which we fully concur.

One of these chronometers had a rate on board of 3" 4""; but, on its removal to the Observatory, its rate was found to be 18′′ 2′′; and

on being taken back again to the ship, the rate was found to be 6" 5"; shewing a change in the ship-rate of 3′′ 1′′.

Another of them, by a different maker, lost about 9′′ by its removal from the vessel to the shore; and a third, by another maker, still more. The variation in the shore rates is also remarkable, that of the first appearing to have been 8"; of the second 6"; of the third, 7" 2""; and of a fourth, 8". And all these errors were noted in the short period of seventeen days.

From the performance of such chronometers, it would surely be unsafe to draw positive inferences as to the effects of any generally operating causes on their rates of going.

Mr. W. C. Bond, of Boston, in America, a gentleman well qualified for the task, has taken much pains to ascertain whether there is any regular and systematic tendency in chronometers to change their rates when put on ship-board; and, in a paper published in the Transactions of the American Philosophical Society, he has given the result of experiments on a great number of chronometers.

When he had opportunity, he found the rate before the chronometer was sent to sea, and its rate after its return, and he took the mean for the shore rate; and, dividing the change in the error which had occurred while the chronometer was at sea by the number of days, he obtained the sea rate.

The following extracts are the results from eighty seven chronometers made by us, with their different numbers, and whose rates previous to the chronometers being placed on ship-board were accurately determined, and the same after their return from the voyage:

Summary.

Number of trials,

Number wherein the average shore rate differed from
the ship-board rate-and the difference,
Number wherein the difference was one second,

4

37 to 254

10

8

ΤΟ

do.

It is evident from these experiments, that there is no general tendency in these chronometers either to gain or lose at sea, on their land rates; as it appears from the above, that, out of eighty seven trials, thirty nine gained on their rates, and thirty nine lost on their rates the remaining nine made no variation whatever.

Mr. Barlow, of the Royal Military Academy at Woolwich, whose attainments in science, skill as an experimenter, and discoveries on the laws of magnetism in particular, are known to all scientific men, took up the subject on the appearance of the Rev. Mr. Fisher's paper, and published the result of his inquiries in the Transactions of the Royal Society. He found, indeed, that chronometers were influenced by their near proximity to masses of iron; but instead of the rates of those which he tried being accelerated, five of the six which he used were retarded, and the acceleration of the sixth was doubtful.

We may be excused for stating, that the one least affected was made by us, and it was constructed on the same principle as the four mentioned above by Captain Sabine, and whose performance, under such extraordinary circumstances, was to us a subject of gratifying remark.

That a material effect on the going of a chronometer would be produced by applying a powerful magnet to it, we have no doubt, as the magnet would then operate as a disturbing force with all the ad

vantage of proximity, but to infer from thence that the rate of a chronometer must necessarily be affected by its removal within the sphere of the ordinary magnetic influence existing in a ship, appears to us not more legitimate than to infer, that, because a chronometer will stop if put in the fire, it will necessarily go ill in the ordinary temperature of a sitting-room.

We are far from imagining, that, because so much has been done for the improvement of chronometers, there is nothing left to be desired; and we shall rejoice unfeignedly at any suggestion which may enable those who are engaged with the delicate task of constructing them, to arrive at this, and by more simple and certain means. Our object in writing to you on this occasion, is to convince those whom it chiefly concerns, that the errors, and causes of errors, on which your respectable correspondents have animadverted, cannot, in the present state of chronometrical science, have any appreciable effect in practice.

We are, Sir, your obedient servants,
PARKINSON & FRODSHAM.

'Change Alley, November 14, 1833.

ART. XXIII.-Necrology of COUNT CHAPTAL; translated and communicated by Dr. Lewis Feuchtwanger.

JEAN ANTOINE CHAPTAL, Count of Chantaloup, was born in the year 1756, at Nozaret, Dep. de la Lozère. After having finished his studies in the college of Rhodes, he went to Montpelier, for the purpose of learning the medical sciences under one of his uncles, at that time, professor of the school in that city; after receiving the degree of doctor, he went to Paris, to devote himself to chemistry, for which he had a particular disposition. He then obtained the newly created chair of chemistry in Montpelier, which, possessing the peculiar talents of an orator, extraordinary memory and all other requisites of a superior teacher, he filled with not uncommon success; and it was here, through his theoretical and practical pursuits, that he founded his great reputation. In the year 1790, he published his Elemens de Chimie in three volumes, which passed through three editions in French, and was translated into other languages. He established several chemical institutions, and among others that of Berard. General Washington, endeavored to induce him to emigrate

to this country and three times sent him an invitation to that effect; the king of Spain also, did the same, offering a salary of three thousand six hundred francs, and an initiating donation of two hundred thousand, provided he would fix himself in his estates; the queen of Naples offered him likewise a refuge in her estates in the year 1793, when talent and fortune were dangerous acquisitions; but Chaptal preferring to serve his country, did not accept of either of these offers. He went to Paris, during the most dangerous time of the revolution and in connection with Berthollet and Monge, he conducted the laboratories for the manufacture of gunpowder from domestic materials. When a more brilliant star began to shine over France, the school of Montpellier was re-organized by Chaptal, and as teacher of chemistry at the new established Polytechnic school, he competed with Berthollet, Fourcroy, Guyton, Morveau and Vauquelin, in displaying the most important and beneficial zeal for the diffusion of science. Bonaparte, confided afterwards to Chaptal, the administration of public instruction, and then when he had discovered his intrinsic merits, he made him minister of the Interior. During the discharge of the functions of that office, he published his work "sur le perfectionnement des arts chimiques en France" and collected sufficient materials for his work "sur l'industrie francoise," and for his "Chimie appliquée aux arts"; promoting at the same time, the most useful arts, and institutions, especially architecture and sanitary establishments. After four years, he took his leave of this station and Napoleon, as an acknowledgment for his distinguished merits, tendered him the order of the legion of honor, and a seat in the Senate, where he was several times elected President, and during the one hundred days when Napoleon was striving to recover his power, he was elected minister of State and director of commerce and manufactures. When, shortly afterwards he retired to private life, he again devoted his time to studies. In the beet manufacture, he spent a large portion of his fortune, and he fed a large number of animals, as for instance, twelve hundred merino sheep of the finest wool, with the residue of the beets. He increased, by his agronomical improvements, the value of his property, so much, that the nett proceeds which were fourteen thousand francs, amounted afterwards to sixty thousand. In 1819, Chaptal was created a Peer, he also was a member of the Academy of Sciences of Paris, and of the Royal Society of London, &c. &c. He lost in the last year of his life a very large portion of his fortune.