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LV. Strictures on a Publication entitled " Clark's Gas Bloiu- 

 pipe." 5?/ Robert Hake, M. D. Professor of Chemistry in t/ie 

 Medical Department oft he University of Pennsylvania, &c. 



XJvi. Clark has published a hook on the Gas Blowpipe, in 

 wliich he professes a " sincere desire to render every one his due." 

 That it would be difficult for the conduct of any .luthor to be 

 more discordant with these professions, I pledge myself to prove 

 in the following pages, to any reader whose love of justice may 

 gain for them an attentive perusal. 



In the year 1802, in a memoir republished in the 14th vol. of 

 Tilloch's Philosophical Magazine, London, and in the 45th vol. 

 of the Anvales de Chimie, I had given the rationale of the heat 

 produced by the combustion of the aeriform elements of wa- 

 ter, and had devised a mode of igniting them free from the dan- 

 ger of explosion. I had also stated in the same memoir, that 

 the light and heat of the flame thus produced were so intense, 

 that " the eves could scarcely sustain the one, nor the most re- 

 fractory substances resist the other," and had likewise mentioned 

 the fusion of the pure earths and volatilization of the perfect me- 

 tals as among the results of the invention. 



Subsequently in the first part of the 6th vol. of American Phi- 

 losophical Transactions, an account of the fusion of strontites, 

 and the volatilization of platinum, was published by me. 



About the same time my experiments were repeated before 

 Dr. Priestley, who gave them the credit of being quite original. 



Some years afterwards, Mr. Cloud, of the United States' mint, 

 who has distinguished himself by the discovery of palladium in 

 gold, having purified platina so as to make its gravity equal to 

 22, requested me to subject it to my blowpipe. In the presence 

 of this gentleman, I was completely successful in dissipating a 

 portion of this pine metal. He was so much pleased with my 

 experiments that he made au apparatus for himself, simplifying 

 that part which was employed for holding the aiiriform agents, 

 by the omission of some appendages which were not necessary 

 to his purpose*. Thus modified, my apparatus was introduced 

 into use by Mr. Rubens Peale ; and has for about ten years been 

 employed by him to amuse visitors at the celebrated museum 

 established bv his father in Philadelphia. 



It appears by the testimony of Professor Silliman and others, 

 that Dr. Hope had, during his lectures at different times within 

 a period of eight years, employed my blowpipe and awarded the 

 invention of it to me. A reference to the third edition of Mur- 

 ray'a Chemistry, published before Dr. Clark professes to have 



* It has been erroneously alleged that he simplified the blowpipe. 



attendeti 



