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of chemically and geologically examining aerolites with a view to 

 determine whether other worlds were inhabited. Aerolites, which 

 were fragments of bodies passing through space, or portions of 

 planets, were of two kinds, — one metallic, and the other sandstone. 

 Imagine the immense importance of finding in these aerolites a par- 

 ticle of a scale or any other traces of organic life ? So regular and 

 interdependent were the laws of nature, that such a discovery, if 

 really made, would determine the question as to whether other worlds 

 were inhabited. 



Colonel J. W. Foster of Chicago, next addressed the meeting. In 

 a lucid and able speech, he contrasted the geology of the east and the 

 west, and described the geological features and characteristics of the 

 United States, taking the valley of the Mississippi as the starting 

 place of observation. After further alluding to these points, he said 

 that although Massachusetts was the first State that was geologically 

 surveyed, yet it was to be regretted that it was still almost a blank 

 in geological science. They knew little of those rocks in Massachu- 

 setts which had been so long subjected to igneous agency. He 

 thought, however, that in a few years a solution of all difficulties 

 would be effected. 



Probably they would find that in the igneous rocks of Nahant they 

 had the Devonian shales of the AVest. Sir William Logan, and a 

 corps of able assistants, were about to investigate these matters. 



Professor T. Steruy Hunt of Canada, gave a geological descrip- 

 tion and history of the New England granite formation. The investi- 

 gation of the last twenty years had gone very far to destroy the 

 commonly received notion that granite was the foundation of all 

 other rocks. They were beginning to learn that instead of the 

 granites being the substrata of the globe, they were rather secondary 

 and derived rocks,— that they were once great beds of gravel or 

 sandstone which had subsequently become crystallized. After speak- 

 ing of the probable age of New England granites, Professor Hunt said 

 that in walking along the shore at Rockport, he could see that the 

 granites were distinctly stratified with alternations of sandstone at 

 different periods. This clearly showed their sedimentary origin, and 

 probably identified them as being the same as the granites north and 

 south, and thus enabled them to class them among the Devonian 

 rocks. Perhaps ten thousand or fifteen thousand feet beneath them 

 might be beds holding fossils of the Silurian type, — the same beds, 

 perhaps, as those cropping out at Braintree. As compared with the 

 rocks at Braintree, the granites probably were of very recent origin. 

 From careful analysis it was ascertained that the Rockport granite 

 contained traces of living organisms. He would mention that with 

 reference to aerolites, chemists had found in them traces which by 



