of them offered, should Mr. Watt desire it, to send him the proof-sheets for correction. Mr. Watt, residing at a distance from town, declined his offer; a resolution which he had afterwards reason to regret; for the consequence has been, that in his paper, as it stands in the Philosophical Trans' actions,' there is a very unfortunate error of the press. The date of the letter to Mr. De Luc, which we have just seen was 26th November, 1783, is there given as 26th November, 1784. It is true that the date of the reading of the paper is rightly given; it has also been lately discovered that the misprint is noticed in the errata at the end of the volume of the Philosophical Transactions' in which it appears; and therefore that error might not always mislead: but, considering all that had previously occurred, it was of great importance that every date establishing Mr. Watt's priority should be accurately printed, and what we shall in this instance call carelessness, even if freed from blame, must on every account remain matter of regret.

But this is not all. Of Mr. Cavendish's paper there were a number of separate copies thrown off, which were widely circulated throughout Europe by himself and his friends, before the seventy-fourth volume of the Philosophical Trans'actions,' in which it was to be contained, made its appearance. These also, it is presumed, had been printed under the superintendence of Dr. Blagden, and of Mr. Cavendish. They all bear on their title-page, that Mr. Cavendish's paper was "read at the Royal Society, January 15, 1783." Moreover, the true date, 1784, which is placed at the head of that paper as it stands in the Philosophical Transactions,' is not given at all in those separate copies. We annex a fac-simile of the erroneous title-page, which, it must be admitted, is most highly suspicious, and, to say the least, far from creditable to the accuracy of Messrs. Cavendish and Blagden.

It is said, on the strength of a draft of a letter reported to have been found among Cavendish's papers, that in one instance, more than a year afterwards, (when the error had already been propagated in most of the scientific Journals of the Continent, and when also the 'Philosophical Transactions'

To face page 334.

with the true date of the reading of the paper had come into circulation), Mr. Cavendish desired that it might be corrected. We have no wish to take from him the credit of having done so, or intended to do so, in that instance, although no proof has been produced of such a letter having ever been actually sent by him, or received by any one else. But the error continued long afterwards to have its natural, unjust effect. For Cuvier, writing at the distance of four and twenty years from the circulation of the erroneous date, has distinctly said, "The experiment of Mr. Cavendish dates from 1781; "the reading of his Memoir, from January, 1783;" and he gives Cavendish the precedence over Lavoisier in their respective published memoirs, making the latter superior only in having discarded the hypothesis of phlogiston.* In his Eloge of Cavendish,† it is true, he alters 1783 to 1784, observing that three years had been occupied "in establish"ing that great phenomenon;" but still his readers are left without the means of knowing which of the two dates is the right one.

Every one must admit, that after the series of events which we have now detailed,-after the zealous attempts to establish priority which had been made by two of the three great claimants for the honour of the discovery, and the public statement which had been put on record by the third, (which, being uncontradicted, might be deemed decisive), it was, truly, most unfortunate that any thing should occur which could give to any of the proceedings, even in appearance, a character not altogether consistent with justice. It was at least a piece of most singular negligence, on the part of the Secretary to the Royal Society who superintended the printing, that those papers should have been circulated with a double error in their dates; that the tendency of both of the errors should have been, to take the priority from Watt, and to give it to Cavendish, the Secretary's intimate friend and patron; and that, of all the errors which the printer'

might have committed, he should have happened to select precisely those which were so well fitted to effect that object.

But we have not yet done with either the history of the discovery, or the share which Dr. Blagden took in it as an auxiliary and historian. Finding that Lavoisier still maintained some claim, and seeing from the note appended to Mr. Watt's paper, and from the total want of any statement as to the chronology of Cavendish's conclusions, that Mr. Watt stood distinctly recorded as the first discoverer, notwithstanding the inexplicable awkwardness of the typographical errors, Blagden thought proper to write the letter to Dr. Lorenz Crell, printed two years later in his Journal, of which the following is a translation: *

"I can certainly give you the best account of the little "dispute about the first discoverer of the artificial generation "of water, as I was the principal instrument through which "the first news of the discovery that had been already made "was communicated to Mr. Lavoisier. The following is a "short statement of the history:

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"In the Spring (Frühjahr') of 1783, Mr. Cavendish "communicated to me and other members of the Royal Society, his particular friends, the result of some experi"ments with which he had for a long time been occupied. "He showed us, that, out of them, he must draw the con

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clusion, that dephlogisticated air was nothing else than "water deprived of its phlogiston; and, vice versa, that water "was dephlogisticated air united with phlogiston. About the "same time (um dieselbe Zeit ') the news was brought to "London, that Mr. Watt of Birmingham had been induced "by some observations, to form ('fassen ') a similar opinion. "Soon after this ('bald darauf') I went to Paris, and in the company of Mr. Lavoisier, and of some other members of "the Royal Academy of Sciences, I gave some account of "these new experiments, and of the opinions founded upon "them. They replied that they had already heard some

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*The letter appears not to have been dated; but it was published in

Crell's Chemische Annalen,' Helmstädt u. Leipzig, 1786, pp. 58-61.