Intelligence and Miscellmieous Articles. 157 



the contrary, the temperature be slowly raised, they lose 14* 1 per 

 cent, of water without fusing ; they are then anhydrous, and fuse 

 only at a temperature a little lower than the salts of barytes and 

 strontia. 



Like these salts also the chlorate of lime loses oxygen at a high 

 temperature, and chloride of calcium with an alkaline reaction re- 

 mains. This salt consists of 



Chloric acid . . 62*54 



Lime 23-36 



Water 14-10 



100- 

 Chlorate of Magnesia. — The neutral solution of this salt, obtained 

 by decomposing chlorate of barytes by sulphate of magnesia, yielded 

 by evaporation over sulphuric acid, a saline mass of crystalline la- 

 minae, which was very deliquescent and readily soluble in alcohol. 

 It was separated from the solution, pressed between folds of blotting- 

 paper, and then perfectly dried over sulphuric acid; it fused at 120° 

 Fahr. ; and at about 248° Fahr. it begins to lose water, oxygen and 

 chlorine. When the heat is continued there is obtained a mixture 

 of magnesia and chloride of magnesium ; if it be heated very rapidly 

 magnesia only is left. 

 It is composed of 



Chloric acid . . 50-25 

 Magnesia .... 13-77 



Water 35-98 



100- 

 Protochlorate of Manganese. — This compound could not be ob- 

 tained in the solid form. The colourless solution obtained by de- 

 composing chlorate of barytes with protosulphate of manganese, 

 decomposes by evaporation over sulphuric acid, at a certain degree 

 of concentration, into chlorine, oxygen and hydrated peroxide of 

 manganese ; the author therefore merely states the properties of a 

 dilute solution : it suffers no change by ebullition ; sulphuric acid 

 diluted gives it a deep red colour ; there being formed sulphate of 

 manganese at the expense of the oxygen of the chloric acid. If a 

 small quantity of solution of protoxide of manganese be added to an 

 excess of concentrated sulphuric acid, a brown crj'stalline precipitate 

 is formed, which is an intimate mixture of peroxide of manganese 

 and sulphate of the protoxide, insoluble in concentrated sulphuric 

 acid. — Journ. de Pharm. et de Ch., Mai 1844. 



PllEPARATION OF PROTOXIDE OF GOLD. BY M. L. FIGUIER. 

 The author states that the substance which Berzelius describes as 

 protoxide of gold is a mixture of the oxide and metallic gold ; and 

 he mentions the following processes for procuring the real pro- 

 toxide : — 



1st. Let a solution of chloride of gold be evaporated to dryness to 

 deprive it of acidity ; to the residue dissolved in water add a solution 



