MUSEUM OF COMPARATIVE ZOOLOGY. 75 



determining the course of a fault, care must be taken to select as guides 

 at least three points, which lie alternately on opposite sides of the frac- 

 ture. It is evident that an error may result from trusting too implicitly 

 to the apparent termination of a ridge, for the real termination may 

 be covered ; but if three ridges, of which the first and third are on one 

 side of the fault and the second is on the other, all terminate on the 

 same straight line, the presumption is very strong that they indicate 

 a straiglit fault and that the indication may be trusted. The case 

 in hand therefore needs additional ridge-endings before the fault line 

 can be established. The south end of Chauncy Peak (11) and of 

 its posterior (15) and the high north end of Higby Mountain (16) 

 serve abundantly for this purpose. The southern end (15) of the ridge 

 posterior to Lamentation and Chauncy is found a little south of the rail- 

 road cut to the east of Highland station, mentioned on the first day's 

 •walk as affording a good exposure of the sandstone overlying the lava. 

 The ridge ends in a little knoll back of a farm house and barn, north of 

 the Meriden-Westfield road. In sighting backward from this knoll, the 

 course of the fault is seen to be curved, and if the middle of the meadow 

 between this point and the north end of Higby be taken as the location 

 of the fault, its curvature is greater still \ but this is hardly more than 

 might be expected : a straight line fault is too rigid to be natural. On 

 continuing the walk to the northeast, a reverse curvature of the fault line 

 is required, in order to leave the long descending ridge (17) of Higby 

 Mountain on its eastern side. The northernmost low end of Higby is 

 found at High Falls (18), where the trap suddenly ends. The little 

 gorge opened by Falls Brook discloses much breccia in fractures running 

 northeasterly, and evidently associated with the strong fault close by. 

 No other outcrops appear for some distance, but a cut on the Cromwell 

 railroad, just west of Westfield station and about a mile and a half north- 

 east of High Falls, reveals strong disturbance in the dip of the shales 

 there exposed, as well as two faults of indeterminate throw. It is likely 

 that these dislocations are associated with the fault that we have been 

 tracing. It is interesting to notice that the course of the fault thus 

 traced curves somewhat in the neighborhood of the north end of Higby 

 Mountain, and that the curvature is closely conformable to that found 

 between the Lamentation and Chauncy Peak blocks. 



On returning to Meriden, a superb view of the valley may be gained 

 by an easy walk up a path leading to the terminal bluff' of Chauncy 

 Peak from the road below it. The strong range known as Beseck Moun- 

 tain, formed on the main sheet, may be traced many miles southward 



