PREFACE 



111 



ity was afforded for this. The photographs of Dr. Heinrich Bies 

 and Prof. I. P. Bishop were chiefly made for the New York State 

 Museum. The photographs by N. H. Darton are from the collec- 

 tion of the Geological Society of America, and printed through 

 the courtesy of the United States Geological Survey; many of 

 these have already appeared in the report of the State Geologist. 

 The remainder have been secured from various sources. 



For many of the general statements concerning the ages and 

 systems acknowledgment is made to the writer's late friend and 

 teacher Dr. John S. Newberry. 



To Prof. James Hall, State Geologist, the writer is indebted 

 for numerous facts and conclusions concerning many of the 

 Palaeozoic strata of New York. 



As it seemed desirable to provide a pamphlet which could be 

 distributed at cost price to all visitors to the museum who were 

 interested in the study of the collections, the bulletin has been 

 made as small as possible, but it has much outgrown the dimen- 

 sions originally contemplated. 



Since the geologic collections of the New York State Museum 

 are not yet in a state of final arrangement, no detailed reference 

 is made in this bulletin to the museum cases, but the system of 

 labelling adopted is such as to make it an easy matter to refer 

 from the guide to the museum specimens. 



It is hoped that this bulletin may, in its function as a. guide and 

 supplement to the geologic collections of the State Museum, 

 prove a useful aid to beginners in geology. It aims, through its 

 text, to place within the reach of those interested, a brief synop- 

 sis of the geology of the state, and by its illustrations made from 

 photographs, to show the exact appearance of many typical 

 exposures. It is hoped that its readers, will receive from it a 

 general idea of the New York formations and will be led to sup- 

 plement by detailed study of local geology the valuable general 

 text-books accessible to all. 



