1876.] Specific Volumes of Liquids. 297 



The observations with the dilatometer have afforded the formula 



V = 1 + 0-000 991 338 5t + 0-000 000 849 U? 



+ 0-000 000 002 755 08< 3 , 

 by the aid of which the following Table is obtained ; it shows the volume 

 of arsenic trichloride at every 10° between 0° and 130°, the volume at 0° 

 being taken as 100,000. 



°0. 



Volume. 



Diff. 



°o. 



Volume. 



Diff. 







100000 





80 



108615 



1165 



10 



101000 



1000 



90 



109811 



1196 



20 



102019 



1019 



100 



111038 



1227 



30 



103058 



1039 



110 



112299 



1261 



40 



104119 



1061 



120 



113595 



L296 



50 



105203 



1084 



130 



114928 



1333 



60 



106313 



1110 









70 



107450 



1137 



130-21 



1-14956 





The specific gravity of arsenic trichloride at 130°-21 is 1-91812 ; hence 

 its specific volume is =94-64. 



Pierre represents the expansion of this liquid by the expression f 



V=l + 0-000 979 072 746* + 0-000 000 966 948 2? 



+ 0-000 000 001 777 204* 3 , 



which gives results uniformly lower than those afforded b) my observa- 

 tions : — 



30°. 60°. 90°. 120°. 



Pierre 1-03029 1-06261 1-09724 1-13448 



Thorpe .... 1-03040 1-06295 1-09805 1-13602 



The specific volume of arsenic trichloride deduced from Pierre's numbers 



is 181 ' 53 =94-891. 



1-91304 



VIII. Antimony Trichloride. 



The rate of expansion of this compound has been determined by Kopp, 

 who has given the following formula to express his observations + : — 



V=l + 0-000 805 4S + 0-000 010 33a 2 , 

 in which $ = the number of degrees above the melting-point of the body, 

 73°-2 (Kopp). According to Kopp antimony trichloride boils at 223°, 

 under a pressure of 747*7 millims. Eeduced boiling-point 223°-5. Its 

 specific gravity at 73°-2, compared with water at 4°, is 2-6753 • at 223°-5 



it is 2-3377. Accordingly its specific volume = 228 '^ 8 § = 97-82. 



* As = 75-15, Kessler; Cl = 3546, Stas. t Loc. cit. 



\ Ann. der Chem. und Pharm. vol. xcy. p. 350. 

 § Sb= 122 3, Kessler, Dexter; CI = 3546, Stas. 

 VOL. XXIV. Z 



