314 ANNUAL OF SCIENTIFIC DISCOVERY. 



seem to forget that all coal plants are tropical, and that peat belongs exclu- 

 sively to the northern temperate and frigid zones. It does not exist in a 

 tropical climate. Peat never occupies vast tracts in basin- shaped layers, 

 but only small irregular cavities, in masses, and not in layers. Peat bogs 

 rest upon rocks of all ages, and of all descriptions, granite, trap, lias, and 

 even drift ; coal does not extend below the carboniferous, and is never 

 seen above the drift. In coal fields, there are alternate layers of shale, 

 sandstone, and coal many times repeated, so that 10, 20, and even 50 seams 

 of coal exist, one above another, in the same spot. Was ever a succession 

 of peat bogs seen covered by rock strata ? 



These are some of the considerations that induce me to give a short, 

 simple and natural solution to the formation of coal strata, and to regard 

 them as sedimentary deposits from the same waters that deposited the in- 

 cumbent and subjacent beds. Carbon, oxygen, hydrogen and nitrogen, 

 the elements of coal, existed bountfully, as minerals, in all geological 

 epochs ; consequently bitumen, which is composed of these ingredients, 

 is found in rocks of all ages. It only requires the application to it of the 

 same principle that operated in the segregation or separation into layers of 

 other minerals, such as iron ore, limestone, gypsum, or salt, and we have 

 beds of coal. How bitumen originated, it matters not for the present pur- 

 pose, if it is not derived from vegetable matter. That it is not, is placed 

 beyond reasonable doubt, by its existence in large quantities, in rocks 

 older than land vegetation. 



All vegetable tissue contains mucilaginous alkaline salts, lime, soda, and 

 potash, as well as silex, iron, and aluminum. If a mass of timber, or 

 other vegetation, was accumulated, and buried, to undergo the supposed 

 change, its mineral constituents must remain ; and the products resulting 

 from it should be caustic like the ashes of wood. The analyses should 

 generally show material quantities of these alkalies. Coal ashes should 

 produce lye for making soap, and should prove as advantageous as ma- 

 nure. Lignite and carbonized wood is no doubt found in the tertiary and 

 drift deposit and in peat bogs, but it has only a very remote analogy to 

 mineral coal. Coal is laminated like the slates, as well as bedded and 

 stratified like sandstone. Carbonized wood retains the form of the 

 trunk, like a piece of charcoal from the pit of a coal burner. 



I have examined in place specimens of timber, and mostly of the resi- 

 nous trees, that exist in the drift materials, buried long before the time 

 when man appeared upon the earth, at depths from 20 to 150 feet from 

 the surface, and at points many hundred miles asunder. Not one specimen 

 in twenty is carbonized at all, but merely decayed, and none of them re- 

 semble coal. But having already exceeded the length I proposed to my- 

 self, I will advance no more reasons why I fiftd it impossible to believe 

 that a large portion of the rocky strata of the carboniferous era was de- 

 rived from vegetation on the surface of the earth. I omit also my idea as 

 to the most probable manner in which coal strata were produced. 



