RECORDS 



OF 



GENERAL SCIENCE. 



OCTOBER, 1835. 



Article I. 



On Racemic Acid. By Thomas Thomson, M.D., F.R.S-, 



&c., Regius Professor of Chemistry in the University of 

 Glasgow. ( Continued from p. 172. J 



XIII. — RACEMATE OF COBALT. 



When solutions of racemate of soda and sulphate of cobalt, 

 in atomic proportions, are mixed together, no sensible 

 change takes place at first ; but, by degrees, the sides and 

 bottom of the vessel become covered with a crust of race- 

 mate of cobalt. 



The colour of this racemate is a fine red, with a slight 

 shade of blue. When heated so as to drive off the water it 

 assumes a fine deep violet colour, which is permanent. It 

 is tasteless, yet leaves a disagreeable impression in the 

 mouth. Its sp. gr. is 1-769. At 60°, 100 water dissolve 

 O'llS parts of it. The solution has a red colour, though it 

 contains only 8-^7*^ P^^* ^^ ^^^ weight of salt. 100 of boiling 

 water dissolve 0*42 of the salt. The solution has a pretty 

 deep red colour. 



To determine the constituents of this salt, 20 grs. of it, 

 previously dried in the open air, during dry and warm 

 weather, were exposed for two hours to the heat of 230°. 

 The colour became violet, and the weight was reduced to 

 14*76 grs. The heat being now raised, the salt blackened, 

 gave out an empyreumatic smoke, and at last took fire and 



VOL. II. R 



