386 Scientific Intelligence. 



Davis, and W. H. Hobbs as the chief contributors. A consider- 

 able part of the information on which this manual is based has 

 been obtained from field work done for the IT. S. Geological Sur- 

 vey and much of which is still unpublished. 



The geology of Connecticut is as intricate and obscure as that 

 of any region of like area in New England and the geology of 

 the New England province is rated as difficult, if not more diffi- 

 cult to unravel than that of any other region in the United States. 

 Consequently in spite of the prolonged labors of three genera- 

 tions of geologists there are many large problems which still 

 await definite solution. The writers, appreciating this fact, state 

 in the preface : 



" To geologists it is unnecessary to say, but to the general 

 reader it is important to say emphatically, that this Bulletin 

 does not aim to set forth a complete and final statement of the 

 geology of Connecticut. In spite of all the earnest study that 

 has been given to this field, there are many questions still 

 unanswered ; and the knowledge which we possess seems small 

 in comparison wi'th the territory of the unknown. The problems 

 presented by the Triassic are simpler than those presented by the 

 crystalline rocks, and have been much more nearly solved ; but, 

 even in regard to the Triassic, important questions still remain 

 without any answer conclusively established or unanimously 

 accepted. 



" Obviously, then, the present paper is in large degree provi- 

 sional. It is a report of progress ; not a final report. It may be 

 hoped that future investigation will Correct some of its errors 

 and answer some of its questions ; but, however many interroga- 

 tion points may be changed to periods in the progress of knowl- 

 edge, it seems not unlikely that for generations to come the new 

 questions which will be started may be more numerous than the 

 old questions which will be answered. The problem of our crys- 

 talline rocks seems, in the present state Of our knowledge, to be 

 analogous to mathematical problems in which the number of 

 unknown quantities exceeds the number of equations." 



These difficulties account for the lapse of sixty-five years with- 

 out the publication of a single comprehensive report on the geol- 

 ogy of the state, and the need of it for teaching local geology 

 had become extreme. 



An outline of the work and a summary of Connecticut geology, 

 dwelling especially upon the earlier events and the less known 

 metamorphic regions, may be given by quoting from the volume 

 as follows : 



" The relation of the successive changes of geological history 

 to the present geographj^ and topography of Connecticut may be 

 briefly summed up in the following statements : — The rocks of 

 the Highlands acquired their present crystalline character in con- 

 nection with the orogenic movements of Archaean and Paleozoic 

 time. The sedimentary rocks of the Central Lowland were 

 deposited in Triassic time, and were derived from the waste of 



