East Haven- Branford Region. 371 



Though many bowlders lie scattered over the eastern slope 

 of the first member of the Pond ridge, none of the overlying 

 sandstone has been observed in situ near the trap, except at 

 the foot of the lake where a soft reddish brown micaceous 

 shale forms the bank for some distance east of the trap. The 

 contact of the two rocks, however, is not exposed. The shale 

 dips steeply to the south of east. Prof. Davis, in speaking of 

 the railroad through the ridge, says : " No overlying sandstone 

 could be found."* It is there, however The exposure begins 

 135 feet east of the south abutment of the wagon bridge, and 

 extends for about 150 feet along the track and southeastward 

 for 500 feet to a point south of the ice-houses on the bank of 

 the lake. Soil and underbrush prevent a determination of the 

 exact extent of the occurrence up the slope, and grass hides 

 the outcrop by the railroad. The rock is soft, sandy shale like 

 that at the foot of the lake ; for the most part dark red or red- 

 dish brown in color but dark green near the contact with the 

 trap. The strike and dip of the shale were obtained at three 

 places by digging and were: strike, N. 16° E., dip, 75° E. 

 The dip of the eastern face of the trap at the contact is 80° or 

 more toward the north of east. Fig. 3 is a plan showing the 

 relation of the sandstone and trap at the two places just de- 

 scribed, as well as the mode of union between the first and 

 second, and second and third parts of Pond Rock. Fig. 4 rep- 

 resents the section exposed by the railroad. 



North of the railroad the overlying sandstone is exposed at 

 but two places near the trap of this ridge : these are on the 

 southern side of the eastern prolongation of the rock. Half a 

 mile east of the Branford-Foxon road a deep ravine (P) cuts 

 into the southern slope of the trap and extends nearly to the 

 top of the ridge. Into this ravine from the south a steep 

 promontory of sandstone forty feet high projects,, forming a 

 triple ravine. The rock of this projection is a rather hard, 

 very coarse sandstone containing some shaly layers ; its strike 

 is N. 60° E., and its dip 45° eastward. The contact is not 

 exposed, but the sandstone is seen within fifteen feet of the 

 trap. Half a mile farther eastward and well up on the slope 

 is the last exposure of the overlying rock (H, on the map), and 

 the contact is shown. The exposure is in a shallow ravine 

 worn by a small stream. The trap is of dark reddish brown 

 color, and, though filled with amygdules of calcite, is very firm 

 where decomposition has not set in The sandstone is coarse 

 and is very hard especially at the contact where it is firmly 

 joined to the trap. Twenty-five feet down the. hill from 

 the contact and a few feet above the trap, the strike of the 

 sandstone is S. 70° E., and its dip 12° S. 



*Bull. Mus. Comp. Zool., 1883, p. 268. 



