472 TEANSACTIONS OF THE AMERICAN INSTITUTE. 



Dr. Vanderweyde. — I have bad occasion during the past year 

 to prove by the printed reports of our proceedings here that my 

 invention had been exhibited and explained, and that very pub- 

 lication proved my protection. 



The Chairman called attention to the provision for depositing 

 in the archives of the American Institute a sealed description of 

 an invention, which it might be desirable not to make public at 

 the time. 



Mr. Roosevelt remarked that merely explaining an invention is 

 not sufficient. Something must have been done, as well as some- 

 thing said, to protect the inventor. 



Jiew subject. — The subject of " Soluble Glass " was selected 

 for consideration at the next meeting. 



Adjourned. 



American Institute, Polytechnic Association, 1 



December 26, 1861. J 

 Prof. Cyrus Mason in the chair. 



AMERICAN GEOLOGY. 



Dr. Stevens. — I propose to-night to speak of two phenomena 

 which have operated in different ages of the world to modify the 

 physical appearance of this continent, viz : Earthquakes and 

 volcanos. 



Three different and plausible theories have been broached by 

 learned men to account for volcanos. It is one of the wonders 

 of the world that there should be anywhere a chimney, constantly 

 smoking, and giving vent to ashes, heated vapors, stones, and 

 oftentimes melted rock flowing as freely as melted tar. When 

 w^e come to analyze the lava from volcanos, we find it precisely 

 similar in its chemical constituents to the hardest rocks, such as 

 granite and trap. An hypothesis, for a time popular, was, that 

 there is a chemical operation going on in the bowels of the earth ; 

 that somewhere in the interior of the globe, are immense depo- 

 sits of sodium, potassium, and the metallic basis of the earths, 

 and that through cracks in the earth's crust, water finds its Avay 

 down to these metals. Sufficient heat, it was assumed, is thus 

 evolved to melt the rocks in the immediate vicinity. This 

 theory, although very ingenious, was abandoned by its author, 

 and is now exploded. The theory of Laplace holds that the 

 interior of the earth is composed entirely of molten matter ; 



