222 



NOTES ON CHINESE MATERIA MEDICA. 



186O-62. like chalk. It consists chiefly of fragments of a botryoidal crust^ 

 showing, when broken, a glistening, fibrous, radiating struc- 

 ture, sometimes divided into bands or layers slightly stained 

 with oxide of iron. Mr. J. D. Perrins, of Worcester, who has 

 obligingly examined the mineral for me, found its specific gravity 

 (taken with precautions to deprive it of the air in its pores) to 

 be 2 '6 7. Mr. Perrins's analysis gave its composition as 

 follows : 



Perrins' s 

 analysis. 



Oxide of Zinc . 

 Carbonic Acid . 

 Water .... 

 Carbonate of Lead 



72-64 



14-95 



10-63 



1-78 



100-00 



From these results, which closely approximate to those obtained 

 by Smithson from the analysis of a similar mineral from Bleiberg, 

 in Carinthia, 1 the following formula may be deduced : Zn 0, 

 C0 2 +2(ZnO,HO), with an admixture of PbO,C0 2 . Zinc 

 Zinc Bloom. Bloom, according to Dana, occurs with ores of zinc and lead at 

 Bleiberg and Eaibel in Carinthia, where it has probably resulted 

 from the decomposition of calamine. 



The Chinese mineral is from the southern province of 

 Kwang-si. As found in the native drug-shops, it occurs chiefly 

 in pieces of from one-quarter to one inch in length. Larger 

 pieces which are perfectly white, are worth 400 cash the tael, 

 which equals about one shilling per ounce. 



Litharge. ?E| [ifc ffj Melh-to-sang ; Litharge (Oxide of Lead). Pun- 



tsaou, Fig. 8 ; Cleyer, Med Simpl, No. 168. 



Red Lead. -^ 7T Wei-tan / Red Oxide of Lead ; Red Lead. 



%$* 7T Tung-tan ; a dull red powder, consisting chiefly of 

 Red Lead and Carbonate of Lime. 



1 Chemical Analysis of some Calamines, by James Smithson, Esq., F.R.S. 

 Nicholson's Journal, vol. vi. (1803), p. 74. 





