Dr. E. J. Mills on Elective Attraction, 



515 



into contact with cold water, partly on account of the great heat 

 ev'olved, and partly to avoid loss by intumescence; complete so- 

 lution took place. 



In the following analytical statement the numbers are, as 

 usual, given in percentages ; but the amount of nitrate is not 

 recorded*, calculation having shown that it did not even remotely 

 approximate, as heretofore, to the undetermined difference : — . 





I. 



II. 



III. 



IV. 



V. 



VI. 



Nitrate taken 



1-4248 



1-9584 



1-8572 



20737 



1-4156 



12175 



Residue obtained .. 



1-9600 



2-5770 



2-4147 



2-7 57 b 



1-8103 



1-5993 



Temperature 



115° 



116= 



116° 



115°-5 



134° 



123^-5 



Constituents of the residue, viz. : — ■ 











Potassic chloride; 34-35 1 30-10 



29-09 



3112 



28-25 



30-72 



Phosphoric oxide. 33-10 



28-79 



27-94 



29'69 



26-23 



29-07 



Value of « 



1-976 



1-990 



1-982 



1-996 



2050 



2011 





The mean of all the values of a is 2*001 ; the mean, omitting 

 that deduced under Y., is 1'991, which is adopted as the most 

 probable value. 



Ccesic Nitrate, 



A commercial specimen of csesic chloride, stated to have been 

 prepared from the deliquescent tartrate by Bunsen^s method, 

 was evaporated with hydric nitrate and fused. Nitration took 

 place with extraordinary facility ; and the fused mass was glassy 

 and fissured, much resembling the fused sodic salt. Solution 

 and filtration had to be resorted to in order to separate a little 

 ferric oxide. Allowing for the weight of this impurity, and of 

 some water which was present, the chloride furnished 116*29 

 per cent, nitrate, theory requiring 115*76. The salt was dried 

 over oil of vitriol, and then exposed to 180° for 3 J hours. Con- 

 tact with the oxychloride developed immediate action, accom- 

 panied by turbidity. At 56° the mixture became partly gela- 

 tinized, with dark orange colour, and emitted an odour of chlo- 

 rine j subsequently a gradual liquefaction took place. The time 



* In a portion of the dissolved residue in VI. the unattacked nitrate was 

 determined by Harcourt's process (Chem. Soc. Journ. vol. xv.) and found 

 to be 51*73 per cent. Either, therefore, the phosphorus and chlorine could 

 not have been combined as previously, or the nitrogen ehminated in the 

 form of ammonia by this method could not have wholly existed as nitrate. 

 The latter hypothesis seems to be the more probable one. While experi- 

 menting to make myself familiar with Harcourt's process, I found that if 

 potassic nitrate be in the presence of hydrate and a small portion of phos- 

 phate, the whole of the nitrate is not decomposed in the ordinary manner; 

 the apparent yield, as proved by a mean of five concordant results, requires 

 multiplying by 1"0689. When the phosphate was absent, a normal number 

 was obtained. 



2L2 



