GEOLOGY. 315 



there was iron ore, lime, silica, magnesia, and other oxides, alkalies and 

 earths as soon as there was calcium or silicium. 



Oxygen gas, which constitutes about one-fourth of the mass of the 

 globe," must have been primeval. Are not chlorine, sulphur, nitrogen, 

 hydrogen and carbon equally ancient ? Is there any rock so old that 

 it does not contain sulphur? 



The dolomites of the metainorphic rocks contain carbon ; and the 

 carbonates generally carry about one-eighth of their mass of this singu- 

 lar substance, Avhich is sometimes an imperceptible vapor, and again 

 the hardest kind of matter known. These dolomites are sometimes 

 found older than the Potsdam sandstone. Nitrogen may not have 

 been found in rocks below the mountain limestone, where it exists in 

 the form of nitrate of potassa. But nitrogen must have been in being 

 before organic life ; for it is one of their component parts, and there 

 could not have been an atmosphere fit for respiration without it. 



Hydrogen is not found in combination with the rocky strata of the 

 earlv feolonncal eras ; but livdro^en must have been present, with 



C 1 ^ 



oxygen, before water could have been formed, and consequently 

 before the deposition of any sedimentary rock. If the ancient seas 

 which deposited the silurian system, were, as their fossils prove them 

 to have been, salt, then their water contained chlorides and chlo- 

 rine in the same manner as our seas do at the present day. 



All the gaseous substances exist now in a free state in the oldest 

 sedimentary strata, and flow out in combination with salts in thousands 

 of mineral springs. The thermal springs that proceed from great 

 depths in the lowest and oldest rocks, bring up carburetted hydrogen 

 and other gases, and chlorides, carbonates, etc., in solution. Almost 

 all the salt wells and the petroleum springs in the above catologue 

 evolve gases, some of them pure nitrogen, and salts of various kinds. 

 All these kindred substances are found wherever man has penetrated 

 the earth or divined its composition, in the oldest as well as the most 

 recent formations, and they include all the constituents of bitumen. 



Chemists regard the various forms of native bitumen, whether under, 

 the name of naphtha, petroleum, seneca oil, mineral tar, or asphaltum, 

 as essentially the same compound, mixed with different proportions of 

 earthy matter, or exposed more or less to the atmosphere, which coag- 

 ulates and hardens it. It is an atomic combination of carbon and 

 hydrogen 6 atoms of each. In the atmosphere it absorbs oxygen 

 and nitrogen. From the same rocks and the same depths there issues, in 

 company with naphtha, petroleum, etc., an inflammable or light carbur- 

 etted hydrogen gas, composed of one atom of carbon to two of hydrogen. 



Having convincing proofs that the elementary substances composing 

 bitumen were in existence and universally diffused in nature before 

 the production of organic life, with the same chemical affinities they 

 now possess and obey, is it philosophical to suppose that they did not, 

 when in contact, obey those affinities until after animals and vegeta- 



* ' 



bles were created V Is it not equivalent to the assertion that carbon 

 and hydrogen did not unite in the proportion of six atoms of each, 

 nor of one atom of carbon to two of hydrogen, till after they had 



28 



