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DENYS PAPIN

CHAPTER XI.

HIS MEMOIR OF 1690

ATTEMPT TO FORM A VACUUM

BY GUNPOWDER HIS SUBSEQUENT ADOPTION OF SAVERY'S PRINCIPLE MISTAKES OF ENGLISH AND OF FRENCH WRITERS TRANSLATION OF HIS PAPER OF

- HIS DIGESTER ·

IN REGARD TO HIS INVENTIONS 1690.

WE come now to the Memoir in which Denys, or Dionysius Papin, in the year 1690, availing himself of the apparatus of Guericke, and of the true ideas, as to a vacuum and the pressure of the atmosphere, of which we have just been speaking, set forth another important fact which he had observed. This was, that if a close cylinder were filled with steam, and the steam were then allowed to condense, a vacuum would be formed within the cylinder; and that, consequently, a moveable piston, fitted to the interior of the cylinder, would then fall, under the pressure of the atmosphere; just as it did in Otto Guericke's experiment, where the vacuum had been formed by the air-pump.

Papin mentions, in the outset of his Memoir, that he had applied steam to that purpose, in consequence of the failure. of a previous attempt he had made to obtain a vacuum by the explosion of gunpowder, in the same cylinder, beneath the piston; the explosion always leaving the vacuum imperfect, on account, as he supposed, of a portion of the air which remained, or, as we should now say, of the gases which were the products of the combustion. But he proposed to carry out his ingenious idea of forming the vacuum by condensation, by the clumsy, tedious, and unprofitable expedient of removing the fire from beneath the cylinder, previous to each stroke or descent of the piston; a method which even the greatest of his admirers among his own countrymen admits was "scarcely tolerable even in an experiment in"tended to verify the accuracy of a principle;" and which

involved so great an expense of time, fuel, and labour, as to make it confessedly of no use in practice.

To practice, accordingly, Papin seems never to have attempted to apply it, notwithstanding the suggestions to that effect contained in his Memoir; and we also find that on the appearance of a better invention for condensing the steam, eight years afterwards, Papin abandoned his own scheme, and betook himself to the construction of an engine, (which, however, turned out not to be a good one), in which he made use of the new plan. As for the applications of a moving-power which he enumerates, and which, if original, would have been ingenious enough, he may have found them, and many more, ready stated to his hand in a book published in London in 1651, entitled, Invention of Engines of Motion lately brought to perfection; whereby may be despatched any work now done in England, or elsewhere, (especially works that require strength and swiftness), ' either by wind, water, cattel, or men, and that with better accommodation and more profit than by any thing hitherto known and used.' This is in the form of a letter to Hartlib, author of a celebrated Discourse on Flanders Husbandry, and many other agricultural works. The unknown author of the Engines of Motion' says, "I have already erected one "little engine, or great model, at Lambeth." See Stuart's 'Anecdotes of Steam-Engines,' pp. 77-79, where it is suggested that the author may have been the Marquis of Worcester.

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The best methods of applying the power to those various mechanical processes, which both Papin and his great advocate M. Arago have treated as difficulties of a very secondary kind, have in reality proved far otherwise; they have exercised the ingenuity of the most eminent engineers for upwards of a century and a half; and without their solution no mechanical power, however great, could be deemed of very much use to the world. The perfection in all kinds of mechanism of which our country now can boast, has not been attained without incessant and most praiseworthy exertion; and it is melancholy to consider how many persons, respectable alike for their talents and character, have

sunk under the difficulty of contriving those practical applications which M. Arago, himself always most honourably distinguished in theoretical research, considered as having been made with so much facility. For, alas! "persons

"whose whole life has been devoted to speculative labours,

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are not aware how great is the distance between a scheme, apparently the best concerted, and its realisation."

There is no doubt that Papin, who was at one time Secretary to the Royal Society of London, was long best known in England by his Digester, described by him in the work mentioned below;* which was published in this country, while most of his other writings, all of them now more or less scarce, were either published abroad, or preserved in the form of memoirs in the Transactions of learned societies. They are therefore inaccessible to most readers, and cannot be continuously examined by any one without very considerable difficulty. The Memoir of 1690, now so much referred to, long lay entombed in the bulky series of the Acta Erudi'torum Lipsia,' and in a small work, a collection of nine of Papin's short treatises, which, although printed in two forms, viz. in Latin at Marburg, and in French at Cassel, both in 1695, is of such singular rarity, that it is even doubtful whether a single copy of it can now be affirmed to be in existence.

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It is from these circumstances alone, we firmly believe, and not from any undue national partiality, that the real claims of Papin to some of his ingenious ideas have been so long overlooked; and, from the same cause, we now quite as commonly meet with over-estimates of the degree of credit which really attaches to his experiments, unavailing in practice as many of them may have proved to be.

Not only some English writers, (as has sometimes been

*'A new Digester or Engine for softening bones, containing the description of its make and use in these particulars :-viz. Cookery, Voyages at sea, Confectionary, Making of Drinks, Chymistry, and Dy'ing. With an account of the Price 'a good big Engine will cost, and of

the Profit it will afford. By Denys 'Papin, M.D., Fellow of the Royal 'Society. London, printed for Henry 'Bonwicke at the Red Lyon in St. 'Paul's Churchyard. 1681.' It was printed by an order of the Council of the Royal Society, of 8th December, 1680, (Signed) CHR. Wren.

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erroneously supposed), but some of the principal French authors also, have betrayed an entire want of acquaintance with Papin's Memoir of 1690, and with the ideas suggested in it; and have grounded their estimate of his merit as an inventor either on his well-known Digester,' or on the inferior sort of steam-engine which he described in 1707, or on both of those machines, but on nothing else of a more recondite or remarkable nature. Thus Belidor, in his great and valuable work published in 1739, says, "Pour dire un "mot de l'origine des Machines mûes par l'action du feu, l'on sçaura que je n'ai trouvé personne qui prit la chose de plus "loin que M. Papin, Docteur en Médecine, Professeur en Mathématique à Marbourg, et Membre de la Société Royale "de Londres, dans la Préface d'un petit ouvrage, qui a pour "titre: Nouvelle manière d'élever l'eau par la force du feu, imprimé à Cassel en 1707,"* &c. M. De Prony, in 1790. after referring to the same work of Papin, says: "Nous ne parlerons pas de la machine de Papin, qui est plus impar"faite que celle de Savery; la grande célébrité de ses expé"riences sur la vapeur est principalement fondée sur l'usage "qu'il en a fait pour dissoudre les os au moyen de son digesteur, très connu sous le nom de marmite de Papin,”† &c. &c. And Bossut, in 1796, has followed a similar course; speaking first of the "marmite de Papin," as described in his work of 1682, and then of the publication which appeared, at Cassel, in 1707. While in England, on the other hand, Stuart and Farey, in 1824 and 1827, (not to name other writers), have both done ample justice to all the contrivances of M. Papin that could be cited in connection with the history of the steame-ngine.

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A Dr. Ducoux, a physician at Blois, who some years ago published a pamphlet on the life and works of Papin,§ dwells on the contents of the latter with what we cannot but term

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prodigious exaggerations; as, for example, when discussing the subject of steam-boats, he hesitates not to call Papin their "inventor," and to describe the English and American nations as a couple of thieves, who have robbed his country of her glory, and then quarrelled about the spoil ! *

Of the ingenuity of Papin's idea of forming a vacuum by the condensation of steam, as well as of the real worthlessness in practice of his contrivance for producing it, we have repeatedly, in former works, expressed our opinion ;—an opinion in which we believe every well-informed and impartial mechanician of either country, without exception, will now entirely concur. But it could hardly have been supposed that a French physician would have ventured to utter such gross invectives against other nations, while he was himself in complete ignorance of the most ordinary works of his own countrymen on subjects such as those of which he professes to treat, and had evidently never seen the volumes,-nay, for all that we know to the contrary, had never heard of the names,-of Belidor, of De Prony, or of Bossut.

But perhaps those authors may congratulate themselves on the escape they have made, in not having been cited by the learned Doctor; for of those who have in that respect not been so fortunate, we observe that some have been treated with little ceremony. In his pages Rench stands for Wren; Hull for Hulls; Edwart for Edward; Thurloé and Cromwel for Thurloe and Cromwell. The consonant which he has very unnecessarily abstracted from "Fitzgeral," he thrice also, unkindly, denies to "M. Tregold." Mr. Robert Stuart, the nominal author of a 'History of the Steam Engine,' 1824, as well as of the amusing Anecdotes of Steam Engines,' 1829, would, we imagine, be puzzled to recognise himself under the title of Sir Robert Stuart; still more so under that of Sir Stuart. And of the orthography of the name of

"Les Anglais et leurs anciens "colons se disputaient ainsi nos dépouilles, comme ferait deux larrons "qui, après avoir détroussé un voy

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