TROCEEDINGS OF THE POLYTECHNIC ASSOCIATION. 452 



expense is constantly influencing vessels from abroad to come 

 here rather than to Boston or Philadelphia. 



Subjects for Discussion. — The following subjects Avere selected 

 for discussion at the next meeting: "The Great Eastern," and 

 "The Crank Motion in Steam Engines." 



Adjourned. 



American Institute, Polytechnic Association, ? 



October-ll, 1861. ] 

 Professor Cyrus Mason in the chair. 



THE geological SERIES COAL. 



Mr. Nash, by means of a drawing on the black board, made an 

 exposition of his views of the position and order of the several 

 metals and minerals in the geological series. 



Assuming as fact, the theory now so well established by the 

 analytic investigations of Laplace and Fourier, that the interior 

 of our globe is in a state of igneous fusion, he found in it the 

 source of the volcanos and earthquakes of the present geologi- 

 cal epoch, as well as of a very large proportion of the formations 

 and convulsions which mark the successive stages of the earth's 

 history. 



The first or lowest formation, in his opinion, was gneiss, a 

 rock apparently stratified. Next in order he placed mica slate. 

 Third, primitive limestone. Fourth, the green stone or horab- 

 bude formation. Fifth, a green stone slate. Next, or sixth in 

 order, Mr. Nash placed the anthracite formation, of the United 

 States, which he considered to be of a primitive order, maintain- 

 ing that the rocks of this series are not secondary, and that the 

 coal has not been acted upon by heat, but is a true mineral in its 

 original state. Next, or seventh in order, Mr. Nash placed a for- 

 mation of semi-bituminous coal, and Avith this formation he con- 

 ceived that the earliest traces of animal and vegetable life were 

 found. Eighth, the salt formation. Ninth, the secondary lime- 

 stone. Tenth, the bituminous formation, which he considered 

 to be of vegetable origin, in opposition to Dr. Stevens who 

 ascribed it to the animal kingdom. Upon this he placed a series 

 of layers of bitumen, shale and limestone. Eleventh, the old red 

 sandstone, as found at Middletown, Connecticut. Twelfth, the 

 sandstone and conglomerate rocks called millstone grit. He 

 then stated that, in his opinion, the trap rocks which Dr. Stevens 



