Geology and Mineralogy. 409 
d or new minerals formed where there was no moistur 
to aid the heat. Professor Cook states that the dip of the Trias- 
Sic sandstone is not everywhere westward, as has often been said, 
but that over a considerable tract of country in the valley of the 
Raritan there is eastward dip. 
The kinds, positions and other characteristics of the Archean 
formation are briefly considered, and interesting sections are 
given showing the conformable relations of the iron-ore beds 
(magnetite) to the enclosing rock. rofessor Cook states that 
he b of : . si of 
folded, faulted and pinched, as are the rocks about them... . 
Hence en vie in connection with the associated stratified 
rocks, the conclusion is unavoidable that they were deposite 
48 sediments and are of the same age with them.” 
The Report for 1874 (p. 56), mentions its detection in the trap 
rocks of New Jerse 
account. of the preservation of the ; : 
> ag appendages. His article is illustrated by a lithographic 
Plate. 
The specimen has been studied also by Mr. C. D. Watcorr, 
and the general result of Mr. Mickleborough confirmed, but with 
new developments as to the structure. Mr. Walcott’s article, 
