MABERY. — COMPOSITION OF PETROLEUM. 293 



0.7172 grin, of the oil and 19.04 grms. benzol gave a depression of 0.925. 



Calculated for C 12 H M C1. Found. 



202.5 204 



The index of refraction was 1.480, and the molecular refraction : — 



Calculated for C 12 H 23 C1. Found. 



60.77 59.9G 



Tridekanaphtene Chloride C 13 H. 25 C1. 



The index of refraction of this hydrocarbon as determined is 1.4745, 

 and its molecular refraction : — 



Calculated for C 13 n 28 . Found. 



60.25 59.84 



The chlorine derivative was formed by the action of chlorine, dried 

 and fractioned under 17 mm. ; it came together for the most part at 

 140°-145°. Its specific gravity at 20° was 0.9747; a Carius deter- 

 mination gave the following percentage of chlorine : — 



0.1674 grm. of the oil gave 0.1137 grm. AgCl. 



Calculated for C 13 H 25 C1. Found. 



16.38 16.78 



In the chlorine derivatives of the higher hydrocarbons the weight of 

 oil that can be taken for analysis is limited, since as in the last analysis 

 the pressure of the large volume of gases formed is more than the tube 

 can stand. The molecular weight of tridekanaphtene chloride was 

 determined at the freezing point of benzol : — 



0.4447 grm. of the oil and 17.88 grms. benzol gave a depression of 0.763. 



Calculated for C^H^Cl. Found. 



216.5 217 



Tetradekanaphtene Chloride, C u H 2 7C1. 



Tetradekanaphtene chloride was readily formed by passing chlorine 

 into the hydrocarbon over water in ordinary daylight ; if the action was 

 stopped with a small portion of the hydrocarbon unacted on, the product 

 consisted for the larger part of the monochloride. After washing and 

 drying, the chlorine derivative was separated by continued distillation in 



