1898.] PECKIIAM — THE GENESIS OF BITUMENS. 123 



be found in the exhaustive work of Mr. Boverton Redwood, which 

 has given results sufficiently accurate for my purpose. These re- 

 sults may be generalized as follows : 



The Pennsylvania petroleums are the purest paraffine petroleums 

 known. They contain small percentages of olefines and traces of 

 benzoles. The same hydrocarbons have been found in other petro- 

 leums, in the distillates from cannel coal, pyroschists, peat, wood 

 tar, fish-oil soap, fish oil under pressure and linseed oil, and also 

 from grahamite, albertite, ozocerite and many other substances of 

 mineral and organic origin.^ 



The Lima and Canadian petroleums contain the paraffine series, 

 with a notable proportion of sulphur derivatives of the paraffines,. 

 formed by substitution ; and also traces of benzoles and nitrogenous 

 basic oils.^ 



The Russian oils contain the benzole hydrides and naphthenes.* 



The California oils, so far as at present known, consist of the 

 benzole hydrides, naphthenes, benzoles and sulphur substitution 

 compounds with a large percentage of esters of nitrogenous basic 

 oils.^ 



The Scotch shale oils contain paraffines, olefines, benzoles and 

 esters of nitrogenous basic oils.^ 



These esters are also found in coal tar and in Dippel's oil, the 

 latter being an oil obtained as a distillate from the gelatine of 

 bones. 



No satisfactory research has ever been undertaken upon semi- 

 fluid malthas or solid asphaltums. They cannot be distilled without 

 decomposition, and no analysis by solution has yet been made that 

 was not highly empirical. It is assumed, rather than proved, that 

 many solid bitumens contain oxygen. They certainly do contain 

 sulphur, and in some instances they contain nitrogen. When dis- 

 tilled upon the large scale solid bitumens are decomposed and 



^ Schorlemmer, Pelouze et Cabours, Warren and Storer, Mabeiy, loc. cit. 



2 Mabery and Smith, Pi'oc. Anier. Acad.,n. %., ^xvvx; Atner. Chem. Jour.,. 

 xvi, ^2,^ 89, 544; xvii, 713; xix, 419. 



3 Beilstein and Kurbatow, Ber. d. D. Chem. Ges., 1 880, p. 18 1 8. Jotir. Amer. 

 Chem. Soc, xiii, 232. Markonikow and Oglobini, Ber. d. D. Chem. Ges., xviii,. 

 2234 ; Ann. de Chim. et de Phys. (6), ii, 372. 



*S. F. Peckham, Prqc. Amer. Phil. Soc, x, ^{45; xxxvi, 154; Amer. Jour. 

 Set. (3) xlviii, 250. C. F. Mabery, your. Frank. Inst.^ cxxxix, 401. Boverton? 

 Redwood, Petroleiini, i, 203. 



' English patents. 



