164 S'lograpMcal Account of [MxRCH^ 



Lime 41 



Silica 35 



Alumine 1.** 



Iron . , 6 



Water 1 



Loss 4 



100 



It is needless to observe, that these are not the constituents of the 

 true hyacinth. 



13. A chemical analysis of the topaz of Siberia. Nova ActOp t. 

 xii. p. 406. He obtained. 



Silica 46-15 



Alumine 46* 15 



Water 0-69 



Loss 701 



100-00 



This, supposing the loss to have been fluoric acid, is an approxi- 

 mation to the analysis of Klaproth. 



14. A new method of forming super- carbonate of potash, with 

 new observations on the carbonate of potash. Nova Acta, t. xiii. 

 p. 257. The method is this: dissolve potash of commerce in water, 

 pour distilled vinegar into the solution till an effervescence just 

 begins to appear, then set the liquor aside. The super-car- 

 bonate of potash crystallizes, and may be separated by the filter. 

 Afterwards acetate of potash may be procured by proper evapora- 

 tion. 



15. A new method of obtaining pure tartaric acid from tartar. 

 Nova Acta, t. xiv, p. 343. The method is as follows: mix 15 

 parts of crude tartar, 4 parts of chalk, and 100 parts of water. 

 When the effervescence is at an end, bring tlie liquor to a boiling 

 heat, then add muriate of lime in small portions at a time, as long 

 as any precipitate falls. Decant off the liquid portion, edulcorate 

 the tartrate of lime, and treat It with 8 parts of sulphuric acid, 

 diluted with Its own weight of water. Digest for two days, then 

 filter and evaporate the Uquor till tartaric acid crystallizes. 



16. Some new remarks on the nature of honey, and on tlw 

 method of bringing its saccharine constituent to a dry state. Ci ell's 

 Annals, \'J'd2, t. i. p. 18. 



17. On the purification of nitre by means of charcoal and alum. 

 Ibid, t. ii. p. 506. 



18. On the combustion of metallic sulphurets without the con- 

 tact of oxygen gas. Ibid. 1796, t. i. p. 239. 



19. A method of freeing sulphuric ether more completely from 

 ailcohol than has hitherto been done. Ibid. p. 429. 



20. Some chemical remarks in a letter to Crell. Ibid, 17975 t. i. 

 p, 480, He describes Kirchhof 's method of obtaining barytes from 



4 



