C. U. Shepard's Reply to F. A. Genih. 39 



ture uneven. Translucent. H. ziz 3''75...4. G. = 4-81. Heated in a 

 tube, affords a little moisMire, becomes inilk-"svhite and opaque* B. 1^., 

 becomes yellow while hot, phospliorescos slightly, swells up and melts 

 with effervescence into a yellow gobule (a slight yellow areola, surround- 

 ing the mass) ; on cooling does not crystallize, but is perfectly glassy, 

 colorless and semi-transparent. In powder, moistened with sulphuric acid, 

 does not tinge the flame of the candle, green. With soda effervesces vio- 

 lently, is brick-red while hot, yellow when cold, affording an abundance 

 of lead globules and a large ring, yellow while hot, but white on cooling. 

 Heated with nitrate of cobalt, it affords the deep blue, characteristic of 

 alumina. Soluble in nitric acid without effervescence. It is chiefly 

 phosphate of lead; but also contains hydrate or phosphate of alumina 

 (or both) and oxyd of zinc. It differs from plombgomme by containing 

 much less water, and possessing an inferior specific gravity. Found in 

 seams and cavities with pyrites, chalcopyrite, quartz and staurotide at the 

 Canton mine in Cherokee Co., Ga. ; and named from the county in which 

 it occurs." 



Dr. Genth's Leading is, *' Cherohine is PyromorpMtey He 

 states that he has received " a genuine specimen" of my mineral 

 from F. W. Harris, and gives these fe\v words as my description 

 of it : '' It resembles wliite lead ore (carbonate of lead) in its color, 

 but possesses the crystalline form of pyromorphite, while it con- 

 tains phosphate of alumina and oxyd of zinc, and further differs 

 from Plumbo-resinite by containing much less water,'' etc. He 

 then goes on to observe that after a special search for water, alu- 

 mina and oxyd of zinc, he could find neither ; that before the 

 blowpipe, it melted easily, and that the globule assumed on cool- 

 ing a polyhedral form. 



I think it must appear imder these circumstances, a wholly 

 gratuitous assumption, that Mr. Harris placed in his hands a gen- 

 uine specimen of the cherokine; and since crystals of pyroraor- 

 phite having a thin Avhite coating of some mineral, are common 

 at the mine, it seems to me most probable, that this was the sub- 

 stance mistaken for cherokine. 



Dr. Genth declares Harrisite to he a pseudoraorph of Copper- 

 glance after Galena^ prefacing his observations upon the point, 

 with the following statement: *' Early in this year I examined 

 the Canton mine, and collected part of the material and data 

 for the follownng investigation. 1 am also indebted to Dr. W. 

 C. Daniell, Prof Julien, M. Deby and W. F. Harris, Esq., for 

 minerals from this mine." 



As favorable to the view taken by Dr. Genth, he would con- 

 vey the impression, that harrisite occurs in a part of the ore-stra- 

 tum where it is accessible to atmospheric changes^ and that in 

 descending, it gives place to ordinary galena. He says, "no 

 harrisite has ever been observed below 141 feet in depth, and it 

 has given place to unaltered galena. It may be found again 

 however, if the ore-stratum of the Canton mine or a similar one. 



