Rathbun.] 342 [April 17, 



It was also in 1864 that Hartt obtained proof of the Pre-Carbonif- 

 erous age of the gold of Nova Scotia. His observations were made 

 at a place called Corbitt's Mills, where the well known auriferous 

 Silurian slates are immediately overlaid, uncon form ably, by conglom- 

 erates, grits and sandstones of Lower Carboniferous age. The lower 

 portion of the conglomerates and grits also contain an abundance of 

 gold, which was undoubtedly extracted from the underlying slates, 

 while the former deposits were in process of formation, and was mixed 

 with the loose gravel material which afterwards became consolidated. 



We owe to Hartt the careful investigation of the relations of the 

 different members of the Carboniferous limestone deposits in the 

 neighborhood of Windsor, Stewiacke, etc., Nova Scotia. He collected 

 and studied the faunae of each separate set of beds with much pains, 

 and in this way was enabled to determine their sequence. The fossils, 

 which are marine, are very numerous, and some new species were 

 described by him in the "Acadian Geology." Much interest attaches 

 to the study of this formation at the above localities, where, in the 

 upper beds, occur many forms common to both the Carboniferous and 

 the Permian, and a great likeness is apparent to the upper members 

 of the Carboniferous system in the western United States, called 

 Permo-Carboniferous. Dr. Meek, who examined the fossils, suggested 

 that we might have here " what Barrande would call an upper Coal- 

 measure, or even Permo-Carboniferous fauna, ' colonized ' far back in 

 the Sub- Carboniferous period." Dr. Dawson has greatly enlarged on 

 Hartt's results, and shows that the divisions made by him are of a 

 more general character than he had supposed. 



In many places in his "Acadian Geology," Dr. Dawson refers to 

 the work of Prof. Hartt in various parts of Nova Scotia and New 

 Brunswick, and it is known that, at the time of his death, he had still 

 remaining some original material from the Provinces which he never 

 had the time to study or publish. 



Upon the organization of the Thayer Expedition to Brazil, by 

 Prof. Agassiz, Mr. Hartt was appointed one of its two geologists, 

 Mr. Orestes H. St. John being the other. This expedition left New 

 York in April, 1865, and returned in July, 1866, having been absent 

 a little more than a year. This was the strong and final inducement 

 that called Hartt away from the geology of his own country. Al- 

 though he was not fortunate in finding a very rich geological terri- 

 tory during his wanderings, while connected with the Thayer 

 Expedition, he saw enough to thoroughly interest him in returning 

 again to Brazil, and in finally giving his whole attention to Brazilian 



