62 Geology, ^c. of tlit Conntctlcul, 



the greenstone in the vicinity very much resemble basalt. 

 The sandstone imbedded is that fine-grained argillaceous 

 variety next to be mentioned. 3. A red, very fissile,/na6/e, 

 argillaceous sandstone. It generally contains small scalesof mi- 

 ca and is abundant almost every where, frequently lying imme- 

 diately upon the greenstone and alternating with it and with ma- 

 ny other varieties of rock hereafter to be mentioned. 4. A 

 Gray Micaceous Sandstone Slate, not argillaceous, grit coarse, 

 very fissile, layers even, some varieties much resembhog 

 mica slate, others containing vegetable remains. 5. A simi- 

 lar slate; but much finer, harder and the layers undulating. 6. 

 A slate approaching in appearance to shale, but very silicious, 

 harder and very fissile, layers straight, surface not smooth, 

 dark gray. 7. Shale, generally bituminous,veryfissile, frequent- 

 ly micaceous with and without Ichthyolites. 8. A slaty rock of 

 the aspect of shale, and sometimes much resembling coal, 

 dividing into numerous small pieces of irregular form, and 

 disintegrating when exposed to the air and moisture. At 

 the falls in Gill. 9. A slate made up chiefly of indurated 

 clay, sometimes micaceous, easily scratched by the finger nail, 

 liable to disintegration. Falls in Gill, and cave in Sunder- 

 land, not abundant. 10. A fragmented rock, the fragments 

 chiefly a reddish brown quartz, appearing as if burnt, ce- 

 ment silicious and apparently ferruginous, rock very hard, 

 and appearing almost like porphyry, unstratified, not abun- 

 dant. In Gill. 11. Gray pudding-stone, distinctly stratifi- 

 ed, layers from six inches to a foot thick. Imbedded nod- 

 ules, quartz, felspar and mica slate, rarely raorfe than an inch 

 in diameter, but very abundant, cement same minerals com- 

 minuted. Island in the falls at Gill. 12. Reddish stratified 

 pudding-stone, coarser than the last, and scarcely differing 

 from the conglomerate accompanying the old red sandstone. 

 Mount Toby, Belchertown and Gran by. 13. Very coarse 

 dark gray pudding-stone, scarcely stratified. Imbedded 

 masses often very large, even a foot in diameter, and very 

 abundant, consisting chiefly of mica slate, argillite and chlo- 

 rite slate; but containing quartz, hornblende, talcose slate, 

 and sometimes granite, cement the same, rocks comminuted. 

 Gill, Montague, Mount Toby, and Durham. Most of the 

 preceding rocks are often found alternating with one anoth- 

 er. 14. A gray imperfect limestone, very silicious, in beds 

 in sandstone slate, not fetid, not abundant, Gill. 15. Fetid 



