Art. XXIV. On the Compound Blowpipe. Extract from the Journal de Physique, of Paris, for January 1818.[14]

CONCERNING HEAT.

"Heat, considered as one of the most important agents, especially in relation to chemistry, and even to mineralogy, has also been the subject of numerous labours, both with regard to the means of augmenting and of diminishing its effects.

"To the former belong the numerous experiments made, especially in England, with the blowpipe, supplied by a mixture of oxygen and hydrogen gases. Mr. Clarke has evidently been more extensively engaged in these researches than any other person, as our readers have perceived in the extracts which we have given from the labours of this learned chemist; but it is proper also to give publicity to the protest (rÉclamation) made to us in favour of Mr. Silliman.

"We have already stated that Mr. Hare, of Philadelphia, first conceived the idea of forming a blowpipe with explosive gas; but as we have not been conversant with the memoirs of the Society of Arts and Sciences of Connecticut, we have not made mention of Mr. Silliman.

"The fact is, that this chemist, Professor at New-Haven, published, on the 7th of May,[15] 1812, a memoir containing the results of experiments made upon a very great number of bodies, until that time reputed to be infusible; and, among others, upon the alkaline earths, the decomposition of which he effected.

"The experiments of Mr. Clarke were therefore subsequent; but, having been made upon a still more extensive list of substances, they are scarcely less interesting.

"It results then, from the experiments of Messrs. Hare, Silliman, Clarke, Murray, and Ridolfi, that there is really no substance which is infusible in the degree of heat produced by this kind of blowpipe.

"In this new department of physics, it is attempted not only to apply the blowpipe to a very great number of bodies, but so to modify the instrument or apparatus as to give it the highest degree of convenience, and especially to obviate the danger of explosion."

pp. 38 & 39.

REMARKS.

As the results produced by Mr. Hare's Compound Blowpipe, fed by oxygen and hydrogen gases, continue to be mentioned in Europe, in many of the Journals, without any reference to the results long since obtained in this country, we republish the following statement of facts, which was, in substance, first published in New-York, more than a year since. It should be observed, that Mr. Tilloch has since published, in the Philosophical Magazine in London, the memoir which contained the American results, and there have been some other allusions to it in different European Journals, and to Mr. Hare's previous experiments; but still this interesting class of results continue to be attributed to others than their original discoverers.

Yale College, April 7, 1817.

Various notices, more or less complete, chiefly copied from English newspapers, are now going the round of the public prints in this country, stating that "a new kind of fire" has been discovered in England, or, at least, new and heretofore unparalleled means of exciting heat, by which the gems, and all the most refractory substances in nature, are immediately melted, and even in various instances dissipated in vapour, or decomposed into their elements. The first glance at these statements, (which, as regards the effects, I have no doubt are substantially true,) was sufficient to satisfy me, that the basis of these discoveries was laid by an American discovery, made by Mr. Robert Hare of Philadelphia, in 1801. In December of that year, Mr. Hare communicated to the Chemical Society of Philadelphia his discovery of a method of burning oxygen and hydrogen gases in a united stream, so as to produce a very intense heat.

In 1802, he published a detailed memoir on the subject, with an engraving of his apparatus, and he recited the effects of his instrument; some of which, in the degree of heat produced, surpassed any thing before known.

In 1802, and 1803, I was occupied with him, in Philadelphia, in prosecuting similar experiments on a more extended scale; and a communication on the subject was made to the Philosophical Society of Philadelphia. The memoir is printed in their transactions; and Mr. Hare's original memoir was reprinted in the Annals of Chemistry, in Paris, and in the Philosophical Magazine, in London.

Mr. Murray, in his System of Chemistry, has mentioned Mr. Hare's results in the fusion of several of the earths, &c. and has given him credit for his discovery.

In one instance, while in Europe, in 1806, at a public lecture, I saw some of them exhibited by a celebrated Professor, who mentioned Mr. Hare as the reputed author of the invention.

In December, 1811, I instituted an extended course of experiments with Mr. Hare's blowpipe, in which I melted lime and magnesia, and a long list of the most refractory minerals, gems, and others, the greater part of which had never been melted before, and I supposed that I had decomposed lime, barytes, strontites, and magnesia, evolving their metallic basis, which burnt in the air as fast as produced. I communicated a detailed account of my experiments to the Connecticut Academy of Arts and Sciences, who published it in their Transactions for 1812; with their leave it was communicated to Dr Bruce's Mineralogical Journal, and it was printed in the 4th number of that work. Hundreds of my pupils can testify that Mr. Hare's splendid experiments, and many others performed with his blowpipe, fed by oxygen and hydrogen gases, have been for years past annually exhibited, in my public courses of chemistry in Yale College, and that the fusion and volatilization of platina, and the combustion of that metal, and of gold and silver, and of many other metals; that the fusion of the earths, of rock crystal, of gun flint, of the corundum gems, and many other, very refractory substances; and the production of light beyond the brightness of the sun, have been familiar experiments in my laboratory. I have uniformly given Mr. Hare the full credit of the invention, although my researches, with his instrument, had been pushed farther than his own, and a good many new results added.

It is therefore with no small surprise that, in the Annales de Chimie et de Physique, for September, 1816, I found a translation of a very elaborate memoir, from a Scientific Journal, published at the Royal Institution in London, in which a full account is given of a very interesting series of experiments performed by means of Mr. Hare's instrument; or rather one somewhat differently arranged, but depending on the same principle. Mr. Hare's invention is slightly mentioned in a note, but no mention is made of his experiments, or of mine.

On a comparison of the memoir in question with Mr. Hare's and with my own, I find that very many of the results are identical, and all the new ones are derived directly from Mr. Hare's invention, with the following differences.—In Mr. Hare's, the two gases were in distinct reservoirs, to prevent explosion; they were propelled by the pressure of a column of water, and were made to mingle, just before their exit, at a common orifice. In the English apparatus, the gases are both in one reservoir, and they are propelled by their own elasticity, after condensation, by a syringe.

Professor Clarke, of Cambridge University, the celebrated traveller, is the author of the memoir in question; and we must presume that he was ignorant of what had been done by Mr. Hare and myself, or he would candidly have adverted to the facts.

It is proper that the public should know that Mr. Hare was the author of the invention, by means of which, in Europe, they are now performing the most brilliant and beautiful experiments; and that there are very few of these results hitherto obtained there, by the use of it, (and the publication of which has there excited great interest,) which were not, several years ago, anticipated here, either by Mr. Hare or by myself.

As I have cited only printed documents, or the testimony of living witnesses, I trust the public will not consider this communication as indelicate, or arrogant, but simply a matter of justice to the interests of American science, and particularly to Mr. Hare.

BENJAMIN SILLIMAN,

Professor of Chemistry and Mineralogy in Yale College.