6 NEW YORK STATE MUSEUM 
€ b) 
ore are confined to certain “ ore ranges” or belts which are sepa- 
rated by large areas of barren ground. In these “ore ranges,” or 
belts, mines have been opened in Orange county: (1) in the vicinity 
of Sterling Lake, (2) near Monroe, (3) near Warwick, (4) about 
6 miles from Fort Montgomery; in Rockland county in the vicinity 
of Sloatsburg; in Putnam county: (1) seven miles east of Cold 
Spring, (2) at Travis Corners, (3) in Sprout Brook valley, about 
1% miles west of Oscawana Corners, (4) in the vicinity of Brewster, 
(5) near Lake Mahopac; in Westchester county: (1) one-half of a 
mile southwest of Croton Falls, (2) 3 miles north of Peekskill. 
In the four counties mentioned over fifty openings have been made, 
ranging in size and importance from mere prospect pits to producing 
mines. 
Acknowledgments 
Through the kindness and cooperation of a number of people the 
progress of this investigation has been greatly facilitated and aid 
and information freely given. 
The writer desires to express his appreciation to the officials of 
the Ramapo Ore Company, and especially to Mr T. M. Williams, 
consulting engineer of the Sterling group of mines, to Mr Charles 
Rees, superintendent of the Ramapo Ore Company; and to Mr H. P. 
Sweeny, now superintendent of the same group, but formerly super- 
intendent of the Forest of Dean mine. These men have accorded 
the writer every possible courtesy and he has drawn freely on their 
knowledge and experience. 
It was the original intention to make this a joint bulletin by Mr 
D. H. Newland, formerly assistant state geologist, and the writer. 
Mr Newland’s retirement from state service placed the burden of 
the work on the writer, who is, however, grateful for the aid given 
by Mr Newland, and who has enjoyed his companionship on several 
occasions in the field. 
The writer is particularly fortunate in his associates, among whom 
are Professors James F. Kemp and Charles P. Berkey; he has 
greatly benefited from discussions and from their advice relative to 
various phases of the work and the never-failing interest exhibited 
by them in the various problems of origin and genetic relationship 
connected with the magnetite and its associated rock. 
