Dr, Genth on the Canton Mine Minerals. 133 



i 



Art. X. — A few remarks in answer to Prof. G. U. SheparcVs 



''Re]olyf' bj R A. Gexth,-^ 



Prof. C. U. Shepard in Lis "Reply to Dr. F. A. Gentirs re- 

 marks on the Minerals of the Canton Mine" in this number of 

 the Am. J. of Science, endeavors to show that I have mistaken 

 some of his species^ and he also blames me for not knowing what 

 he wrote in the second part of his Treatise on Mineralogy, a book 

 of which incomplete copies may have been distributed amongst 

 some personal friends, but which as far as I can learn, has not 

 been advertised in any of the catalogues of the leading book- 

 sellers of this country. 



I have not time at present to answer liis "Eeply" in detail. 

 It may suffice to say that I have made a qualitative analysis of 

 a specimen of genuine Hitchcockite, which Prof. J. D, Dana was 

 so kind as to send me, and of which he says in his letter, dated 

 I^ew Haven 11th, May 1857, as follows : "I give to the express 

 for your examination a specimen which he (Prof. Shepard) in- 

 formed me was ' true^ Hitchcockite." 



The physical properties are exactly the same a^ those of the 

 Hitchcockite which I have analyzed, although it is less pure than 

 the material selected for my analyses. Before the blowpipe with 

 carbonate of soda it gives lead incrustations and metallic lead, 

 but no incrustations of zinc whatever. An examination of its 

 solution in chlorhydric acid proved that the mineral contains 

 oxyd of lead, alumina, a trace of sesquioxyd of iron, and phos- 

 horic acid, but not a trace of oxyd of zinc. I may therefore 

 3 permitted to presume that if IProf Shepard has been mis- 

 taken in one instance, he may be mistaken in the others of which 

 I spoke in my last Contribution t-o Mineralogy. However, if 

 Prof. Shepard will satisfy me by genuine specimens of the cor- 

 rectness of his determinations, I will very cheerfully examine 

 them, and publish the results of my investigations. 



I do not think the occasional publication of ''new minerals" 

 with a loose description attached to them to be of any benefit to 

 science at all, and consider it the duty of every one, who is able 

 to do so, to examine into the merits of alleged new species and 

 to endorse them, if they are really good, and denounce them 

 at once, if they cannot be sustained by a more thorough 



mT 



tigation. 



May 



♦ At Professor Shepard's suggestion, a copy of his paper ■was sent to Dr. Genth, 

 as soon as the sheet was priuted.— Eds, 



