THE SUGAR LOAF ARKOSE. -357 



The rock is everywhere a coarse puddiiig--stone, tlie large pebbles of 

 vein quartz and schist being derived from the adjacent bluffs of mica-schist 

 and growing smaller and rarer as one recedes from the bluff in going east- 

 ward, until in the Deerfield River they are mostly wanting, while the paste 

 in which these large pebbles are embedded is a coarse arkose with much 

 kaolinized feldspar and muscovite, which could not have been furnislied ])v 

 the dark schists that make the shore for miles north and south, ])ut which 

 have drifted up, as before indicated, from the south. 



From this point on the arkose abuts against the western wall clear 

 across the State. The exposures are poor, but the shoreward portion is an 

 arkose-conglomerate with pebbles rarely lai-ger than 8 inch cube. Thus, at 

 Wliately, in the roadside near the school south of the village, the arkose 

 contains 8-inch pebbles of a coarse granite exactly like that of Williams- 

 burg, in a mass of coarse granitic debris, while the adjacent argillite and 

 tonalite are wanting. 



The next place where the conglomerates are exposed near the j unction 

 is at Loudville, where the arkose is in coarse pebbles 2 to 3 inches across, 

 and in the old adit the contact between the two was cut thi'ough. Here 

 the feldspar grains are often soft kaolin. 



In 1868 Amos Eaton described with great care the rocks of the Loud- 

 ville adit. Beginning 800 feet from the mouth, vertical strata of granite- 

 schist and serjjentine continue for 134 feet east, toward the tunnel mouth. 

 Then a "gi'een granular aggregate" appear; which "begins to approach a 

 horizontal position." This continues (36 feet and is followed by a "granu- 

 lated schistose aggregate chiefly of quartz and mica." 



At 480 feet a half-inch coal stratum appears and runs on to 300 feet, 

 where it goes below the floor of the adit. The green aggregate is the first 

 Triassic bed, and the sudden transition seems to indicate that the two are 

 faulted against each other. The green color is probably due to the intro- 

 duction of surface waters into the crushed liand along- the fault, which 

 have reduced the iron oxide and discharged the red color. The sandstone 

 dips east here, as the coal bed indicates. 



The next contact of the conglomerate can be seen in Southampton, a 

 mile south of Grlendale, on the Great Mountain road. As usual, it is a gran- 

 itic conglomerate, but its coarseness does not reach that of the eastern beds. 



South of the mouth of Westfield River, across Westfield, Southwick, 

 and into Connecticut, till rests against the bold, continuous bluff and con- 



