54 CONNECTICUT GEOL. AND NAT, HIST. SURVEY. [Bull. 



Boston Soc. Nat. Hist., Proc, xviii, 272-284, 1876. Ab- 

 stract: Am. Nat., x, 127, 1876. 



Evidence obtained from various quarries showing that rocks are in 

 a state of tension or compression. Shown by bulgings, crushings, and 

 explosions when rock is removed from the quarries. Due to lateral 

 pressure occasioned by the contraction of the globe. A general phe- 

 nomenon. Among other localities observed were those of Waterford 

 and Groton. (See Johnston, 174.) 



226. Norton, H. 



Glacier scratches in Goshen, in northern Connecticut. 

 Am. Jour. Sci., (3) xxii, 322, 1881. 



Citation of observations of location and direction of five glacial 

 striae in Goshen, Connecticut, as follows: S4i°E; S77°E; S38°E; 

 S22^°E; S58°E. 



227. Peet, C. E. 



Glacial and post-Glacial history of the Hudson and 

 Chaniplain valleys. 

 Jour. Geol., xii, 415-469, 617-660, 27 maps and figs., 1904. 



The relation of the Hudson water body to that of the Connecticut 

 valley is briefly discussed. 



228. Percival, J. G. 



Notice of the locality of sulphate of barytes, from 

 which a specimen was analyzed by Mr. G. T. Bowen, and 

 of various other mineral localities in Berlin, Connecticut. 



Am. Jour. Sci., (i) v, 42-45, map, 1882. 



The sulphate of barytes is found in a vein in a ridge of greenstone 

 within the red sandstone formation, about one-half mile west of 

 Kensington meeting house, in Berlin. Mentions a coal mine (in green- 

 stone only), lead mine, pyrites, carbonate of lime, quartz, chalcedony, 

 agate, porous greenstone containing zeolites and chlorite crystals. 



229. Percival, J. G. 



Report on the geology of the state of Connecticut. 486 

 pp., with map, published under the direction of the Com- 

 missioners appointed by the State, 1842. 



The geology of Connecticut is discussed under the following heads: 

 Rocks, 10-452; unconsolidated materials, 453-467; soils, 467-470; eco- 

 nomic results, 470-475; physical geography, 475-486. The rocks are 

 grouped as Primary system, 11-298, divided into the western Primary 

 system with 16 rock formations, and the eastern Primary system with 

 5 formations and numerous subdivisions; trap rocks, 299-426; the Sec- 

 ondary rocks, 426-452. The rocks and formations are described in detail, 

 as regards their " mineral composition, structure, and physical charac- 

 ter." The characters of the unstratified " Diluvium " and the stratified 

 " Alluvium " are described at many localities. 



(Percival's report is a remarkable piece of work. The difficulties 

 under which it was undertaken, and the care with which it was done are 

 explained in the bulletin accompanying the Preliminary Geological Map 

 of Connecticut. The rock types and localities are described accurately. 



