440 TRANSACTIONS OF THE AMERICAN INSTITUTE. 



the vast benefit to mankind, to arise from a general unity in the denomina- 

 tions and value of coin, and a unity of standard weights and measures. 



Dr. Rowell, Messrs. Fisher, Roosevelt, Dennis and Stevens, took part in 

 the discussion, after which " Novelties at the Fair" was selected for dis- 

 cussion at the next meeting. Adjourned. 



'1 



American Institute Polytechnic Association, 

 September 17, 1863. 



Chairman, S. D. Tillman, Esq.; Secretary, Enos Stevens. 



Origin of the Coal Formations. 



Dr. R. P. Stevens. — Mr. Chairman, I desire to say a few words in con- 

 nection with the paper I read at the last meeting. The theory has been 

 advanced for a long time that, in that age of the world in which the large 

 coal deposits were formed, the atmosphere was more thoroughly charged 

 with carbonic acid gas than at the present day; and hence, it is inferred 

 that there was a more prolific vegetable growth at that period, and that 

 this accelerated growth was necessary to eliminate the excess of carbon in 

 order that animals might live, increase and multiply. 



The origin of mineral coal is a disputed point at the present day. Its 

 vegetable origin is claimed on the ground that the annular growth of 

 several varieties of trees, very distinct, were discovered in it; but the 

 same facts exist in the slates, and we might claim for them a vegetable 

 origin also. Thoroughly carbonized fossil shells and fossil bones are found 

 in coal; why not ascribe its origin to these? 



The theory which I advance is one that is adopted by an eminent Ger- 

 man chemist, now living in Ohio; and which was formed after a careful 

 examination of the peat bogs of Europe and America. The theory is, that 

 nearly all the coal beds were but ancient peat bogs. Peat, we know, is 

 formed from mosses. 



Prof. Vanderweyde. — "Where did the mosses that formed the peat obtain 

 their carbon? 



Dr. R. P. Stevens. — They got it from the atmosphere. During the car- 

 boniferous era, the prolific growth of vegetables passed away in the same 

 manner as that of the present day. There are regions that have been for 

 centuries covered with forests and plants that have flourished and decayed, 

 and the remains of which were never disturbed by any leading force, and 

 still the earth on which they lived and perished is covered with a very 

 small amount of vegetable matter. From this, we infer that the growth of 

 that period when the coal was formed passed away in a similar manner. 

 It is stated, in proof of the vegetable origin of coal, that there has been 

 found submerged wood and peat turning into coal, and itS'bituminous nature 

 is given to it by decomposed water. But the advocates of this theory are 

 yet undef'ided whether the bitumen lias its origin in wood and water. 



The theory which I incline to is, that the atmosphere, in the time of the 

 ffreat coal formations, was precisely the same as at the present day, and 

 that vegetation was exactly the same; for air-breathing animals have lived 



