116 PECKHAM — ;THE GENESIS OF BITUMENS. [April l, 



part the rocks of Canada, New England, eastern New York and the 

 eastern slope of the Alleghenies southward through New Jersey, 

 Pennsylvania and Virginia. Speaking of these rocks. Dr. Hunt 

 says, "^ In the oldest known of them, the Laurentian system, great 

 limestone formations are interstratified with gneisses, quartzites and 

 even with conglomerates. All analogy, moreover, leads us to con- 

 clude that, even at this early period, life existed at the surface of 

 the planet. Great accumulations of iron oxide, beds of metallic 

 sulphides and of graphite, exist in these oldest strata, and we know 

 of no other agency than that of organic matter capable of generat- 

 ing these products.^ .... Bischof had already arrived at the 

 conclusion, which in the present state of our knowledge seems 

 inevitable, ' that all the carbon yet known to occur in a free state 

 can only be regarded as a product of the decomposition of carbonic 

 acid, and as derived from the vegetable kingdom.' He further 

 adds, ' living plants, decomposed carbonic acid, dead organic 

 matters, decomposed sulphates, so that, like carbon, sulphur, 

 appears to owe its existence in the free state to the organic kingdom.' 

 As a decomposition (deoxidation) of sulphates is necessary to the 

 production of metallic sulphides, the presence ot the latter, not 

 less than of free sulphur and free carbon, depends on organic 

 bodies ; the part which they play in reducing and rendering soluble 

 the peroxide of iron, and in the production of iron ores, is, more- 

 over, well known." ^ 



Rocks of the Lower Cambrian in Great Britain as well as in North 

 America are well known to exhibit carbonaceous remains. Of the 

 former it is said, ''They occasionally hold flakes of anthracite, and 

 small portions of mineral pitch exude from them in some localities." 

 The rocks of the Malvern hills contain fucoids. In the Quebec 

 series on the south shore of the St. Lawrence, Hunt describes the 

 occurrence of a carbonaceous substance, ''entirely distinct from 

 coal, which occurs in fissures, sometimes in the interstices of crys- 

 talline quartz. It is an insoluble hydrocarbonaceous body, bril- 

 liant, very fragile, giving a black powder, and results apparently 

 from the alteration of a once liquid bitumen." ' Similar material 



^On the north shore of Lake Superior, I have found spherical concretions 

 of graphite occuring in a rock that is apparently eruptive. 



'^ Essays, pp. 301, 302. Am. Jour. Sci., 1871. 



3 Essays, pp. 382, 396. W. Hodgson Ellis, " Analysis of Some Precarbonifer- 

 ous Coals," Chem. News^ Ixxvi, 186, Oct. 15, 1897. 



