Intelligence and Miscellaneous Articles. 151 



Bromic aether being the heaviest of the fluids resulting from the 

 decomposition of aether by bromine, it is very easy to separate it 

 from the other products. It is still to be decided whether this is a 

 separate compound, or a mixture of various substances. — Ann. de 

 Chimie, March, 1836. 



ON THE COMPOSITION OF THE CRYSTALLIZED HYDRATE 

 OF POTASH. 



M. Walter obtains hydrate of potash in fine crystals by pouring 

 on three or four pounds of fused potash a little water, and when 

 the mixture is cool, adding sufficient hot water to dissolve the re- 

 mainder of the potash: at the expiration of 12 hours, by decanting 

 the solution, the crystals will be found at the bottom of the vessel. 

 The method of analysis adopted for determining the relative pro- 

 portions of water and potash, was to neutralize a known weight 

 of the crystals with hydrochloric acid, to evaporate the solution to 

 dryness, and heat the resulting chloride of potassium to redness. 

 4-065 gram, of crystallized potash afforded 3*207 gram, of chloride 

 = l-eS'i gram, of potassium ; and as 1'684< gram, of potassium = 

 2028 of potash (protoxide of potassium), the crystallized hydrate 

 will be composed of 



2-028 potash, 

 2-0S7 water, 



4.-065 

 which nearly agrees with the formula of 10 eqs. of water to I of 

 potash. 



The slight difference between the experimental and the calculated 

 results is evidently owing to a little interposed water, and some 

 slight degree of humidity which the surfaces of the crystals acquired 

 during weighing. 



There is also a third hydrate of potash, for 2462 gram, of the 

 crystals placed under the air-pump lost 0*527 gram., which indi- 

 cates a compound of 21'4' water and 78*6 potash in 100 parts, or 



1 eq. of potash 48 = 77*71 



3 eqs. water 27 = 22*29 



75 = 100*30 

 Thus crystallized potash appears to lose 7 eqs. of water in va- 

 cuo. — Journ, dc Pharm., June, 1836. 



Note. — How this crystallized hydrate can be regarded as a com- 

 pound of 1 eq. of potash and 10 of water 1 am at a loss to know, as the ana- 

 lysis ap|)roximates to 1 eq. of potash and 5 of water; but in any case the 

 analysis docs not indicate any atomic combination, for by it 48 of potash 

 will combine with 483 of water, the equivalent of potash and water being 

 respectively 48 and 49. — J. S. D. 



ON THE COMBINATIONS OF CHROMIUM WITH FLUORINE 

 AND CHLORINE. 



Henry Rose has submitted the gaseous perfluoride of chromium 



