484? Intelligence and Miscellaneous Articles. 



boiling water were poured on. A portion of the powder collected into 

 small lumps, which floated, and, even after violent agitation, adhered 

 to the sides of the vessel; while another portion sank to the bottom. 

 The vessel remained covered seventy-two hours • the contents being 

 frequently agitated, to ensure perfect contact and admixture. The 

 water was then carefully filtered, and the filter dried. The residuary 

 undissolved powder weighed 10*46 gr. Therefore, 



20-1046=0-54 gr. dissolved by f Sviij. or (500x8) 4000gr. water; 

 and 4000-^954=419 } as also 9 54-j-4=2-385 gr. 

 Hence, 



1000 parts water at 212°, dissolved 2-385 pts. or ^fr. 



" Exp. 2. A similar experiment was performed; and the residuary 

 powder obtained on the filter weighed 9*27 gr. Therefore, 



20— 9 27=10-73, dissolved by fg viij. or (500x8) 4000 gr. water; 

 and 4000—10-73=372; as also, 1 0-73-f- 4=2-6825 gr. 

 Hence, 



1000 parts water at 212° dissolved 2-6825 gr. or -^. 



" Twenty-five grains of each of these solutions, filtered, were now 

 evaporated to dryness, at a low temperature ; and '06 gr. were ob- 

 tained as the mean weight of the residue of several successive evapo- 

 rations of Exp. 1 . ; and '07 as the mean for Exp. 2. ; results which 

 come as near to the proportions above ascertained as could be well 

 expected, considering that distilled water was not employed. 



M The mean of the Exps. 1 and 2 will be the following : 1000 gr. 

 of boiling water, allowed to cool, and remain 72 hours (with frequent 

 agitation), on 20 gr. arsenious acid, will dissolve 2*53 gr., or about 

 -r^-s- of their weight. 



" Exp. 3. Two ounces of water were kept gently boiling for an 

 hour, the waste by evaporation being made up ; and while boiling, 

 finely powdered arsenious acid, in small quantities at a time, was gra- 

 dually added, from a previously weighed quantity. No further por- 

 tion was added until that which had been previously added was dis- 

 solved. The result was, that, 



1000 gr. of water (fgij.) dissolved .... 315 gr. or ? V- 

 This solution was placed aside for 72 hours ; and at the end of that 

 time it was found to have deposited in brown octohedral crystals, 14*5 

 gr. ; and 31*5— 14*5=17 gr. Hence, 



1000 grains water (f gij.) held dissolved, on perfect cooling, 17 grains, or^V 

 Twenty-five grains of the cold solution were slowly evaporated to dry- 

 ness ; and the mean of several evaporations gave *4 1 gr. as a residue, 

 which is a little below the proportion as above ascertained. 



" Exp. 4. Two ounces of water were kept violently boiling for an 

 hour, the waste by evaporation being made up ; and arsenious acid 

 was gradually added from a weighed quantity, as before. It was then 

 found that 



1000 gr. of water had dissolved . . . 463 or ,4. 

 From this solution there were deposited in crystals, after 72 hours, 

 21*6 gr. and 46*3—2 1-6=247 gr. 



1 000 gr. water, held dissolved, on perfect cooling, 24-7 gr. or T V- 



