rE 
Geology, &c. of the Connecticul. 67 
very similar to the shale containing the ichthyolite at Sun- 
derland. Thickness 1 rod, dip 40° 
No. 27, Same as No. 24. 2 feet thick, dip 40.° 
o. 28. A stratum of coarse grayish sandstone, ee 
conglomerate, 2 2 oe wide, dip 40° 
N as No. 24. Thickness 5 rods, dip 40°. 
No. 30. ne feet. It may be well, perhaps, here 
to remark, that shale usually forms the roof and floor of coa! 
beds, and ‘that this geest and that of No. 25 lie immediately 
below shale. Connect this fact with another, ‘that the seams 
and other indurated strata are found to do; for on account 
of the tender and more friable texture of the coal, the super- 
ficies of the stratum is often mouldered down and lies con- 
es 
here described, (which I suspect to re quite doubtful,) the 
best spots to search for it are Nos. 25 and 30. 
No. 31. Shale—10 feet thick, on 40°, containing abun- 
dance of nodules of argillaceous iron ore? Rock rather hard 
for pure shale, not liable to much. disintegration. 
N Coarse, gray, sandstone or conglomerate—Rock 
harsh to the touch, imbedded masses not large, layers thick. 
Thickness two a dip 40 
No. 33. Same as No 24. " Thickness 3 rods, dip 43°, 
No. 34. Riglenshisaiasainn with, and passing into, a 
bluish, gray, fine grained slate, harder than the shale, thongh 
perhaps only a variety of it. A little micaceous. Thick- 
ness 3 rods, dip 43°. 
o. 34. Blackish gray slate—Similar to that mentioned 
under the last No. but less fissile and much harder, indeed, 
it breaks with nearly as much difficulty as greenstone, and 
where it is worn by the water it somewhat resembles that 
rock. For it contains numerous irregular cells, sometimes 
two inches in diameter, formerly filled, probably with argilla- 
ceous iron ore? On breaking the rock its structure is slaty 
and it is alittle micaceous. ‘Thickness 2 feet, dip 40°. 
o. 36, rse grayish sandstone or conglomerate—like 
No. 32, layers 2 feet thick. Thickness 20 feet, dip 40°. 
