280 PROCEEDINGS OF THE AMERICAN ACADEMY. 



I. 0.1444 grm. of the oil gave 0.4575 grm. COo and 0.1885 grm. H2O. 

 II. 0.1451 grm. of the oil gave 0.4533 grm. CO2 and 0.1848 grm. HoO. 



Calculated for Found. 



C,„H,o. I. II. 



C 85.70 85.65 85.24 



H 14.30 14.22 14.33 



UnDEKANAPHTENE, C11H22. 



The specific gravity of this fraction without purification was 0.8093 at 

 20°, and after treatment with the fuming acid and sodic hydrate, 0.7952. 

 A combustion gave the following percentages of carbon and hydrogen: — 



0.1458 grm. of the oil gave 0.4593 grm. CO2 and 0.1817 grm. H2O. 



Calculated for C]iH22- Found. 



C 85.70 85.90 



H 14.30 13.85 



Assuming, which is probable, that the benzol homologue was com- 

 pletely removed, these proportions of carbon and hydrogen point to the 

 presence of a hydrocarbon of a series containing less hydrogen. 



A similar result was obtained with the fraction 194°-196°, specific 

 gravity crude, 0.8145, and after treatment, 0.8022. Combustion of the 

 purified oil gave the following percentages : — 



I. II. 



C 85.52 ' 85.85 



H 13.97 13.92 



While the percentages of carbon in these analyses are satisfactory for 

 the formula Q.Ho,,, the percentages of hydrogen are less satisfactory. 

 The deficiency of about one half of one per cent in the sum of the carbon 

 and hydrogen has appeared in many of the analyses of products that 

 could be reasonably accepted as to their formula. With the greatest 

 care in the details of analysis, we have also found difficulty in obtaining 

 the total carbonic dioxide evolved by combustion of the oil in the ordi- 

 nary method of analysis. This subject has received attention in another 

 paper on this method of analysis. 



TrIDEKANAPHTENE, C13H26. 



After the separation of distillates in vacuo from the crude oils, the 

 fractions may be distilled at temperatures which would cause decomposi- 



