*lLmployment of Plathm in Pore f Iain Painting. 13* 



5th, That by help of the nitric acid a matter aaalogous 

 to resins mixed with aclipo-cira is separated from it. 



6th, That concentrated sulphuric, muriatic, and oxy- 

 genated muriatic acid char it without dissolving it. 



7th, That w itli alkalies it forms a saponaceous compound. 

 8th, That fixed and volatile oils, ether, and alcohol, are 

 the true solvents of ambergris. 



9th, That alcohol at^'ords the means of separating its con- 

 stituent parts in the following proportions : 



Grammes. 

 Adipo-cira - - - 2-0 1 6 

 Resin - - _ i-ie; 



Benzoic acid - - 0*425 



Carbonaceous matter - 0-2 12 



3-820 



XIX. Ohservalions on the Employ ment ofPlatina in Porce- 

 lain Painting. By Professor Klaproth, of Berlin*. 



XN the course of half a century since platina was introduced 

 and known in Europe, the experiments made with it by 

 various eminent chemists seem to have exhausted every 

 thing that relates to the physical and chemical properties of 

 tiiis remarkable metal. The imperfect information, how- 

 ever, which relates to its mineralogical and natural history 

 seenjs to rf.quire iiuther investigation, though it must at 

 the same time be acknowledged tliat our information in 

 this respect appears to be worthy of confidence, as the Spa- 

 nish government has entrusted the inspection and manage- 

 ment of its mines in South America to men who to a, 

 knowledge of mineralogy and mining vmite great zeal for 

 the improvement of these sciences. 



The real origin of platina is in all probability to be 

 ascribed to revolutions which have taken place in the Cor- 

 dilleras !)y \()lcanoes, earthquakes, and inundations 5 and it 

 is not impnjbable that these mountains still contain in their 

 ifiterior parts entire veins of platina, the discovery of whieb 

 is perhaps reserved for future times. 



At present, Peru is the only known country where pla- 

 tina is found, and particularly the district of Choco, where 

 it is collected in the valleys between the -mountains and 

 ri\ers along with the gold in small laniinai, or it is ob- 



** From Sihcrci's Allgetmlnf; "Journal dcr Chemie, no. 52, jSoi. 



I 4 t;iincii 



