CARBON STRATA DEPOSITED AS AN AQUEOUS SEDIMENT.
Carbon composing a peat bed is simply unconsumed carbon. The carbon or smoke that arises from every chimney and furnace when measurably shut up from immediate union with oxygen, remains an unburnt fuel precisely the same in kind as the unburnt carbon fuel of the peat bogs. Were we to collect the unburnt carbon from our chimneys in piles, where moisture and air could have free access, it would take fire spontaneously and burn, just as peat dug from the bog sometimes takes fire and burns.
The millions of fires from foundries, volcanoes, etc., are forming fuel wherever soot is formed, and were it not for the ever active oxygen of the air, it would all descend upon the earth as fuel and become incorporated in forming sedimentary beds. This is our claim for the coal, which as unconsumed carbon arose beyond the reach of destroying oxygen, from the heated, glowing furnace of our globe, and in time returned to the earth.
When the plant dies and begins to decay one of its constituent elements, carbon, oxydizes by slow combustion and returns to the air as an invisible gas. It is but accidental when a particle fails to become oxydized and remains as unconsumed carbon. An exceedingly small part of vegetation remains unburnt.
Coal veins, which are from one foot to three hundred feet thick, would make a stratum around the earth ten feet thick. Fifty pounds of coal will yield 10,000 gallons of carbonic acid. Then calling eight gallons equal to one cubic foot the astonishing fact comes out that the coal beds actually draw from the atmosphere an ocean of carbonic acid which would have covered the globe to the depth of 12,500 feet, which would have destroyed all animal life. Even three or four per cent. of carbonic acid in our present atmosphere would be fatal to animal life. Hence it is clear that coal cannot be attributed to vegetable origin.