GLACIAL STEI^. 



527 



on Mount Holyoke, are some of the most remarkable grooves I liave 

 seen. One northeast of the house, between tlie two iron boundary posts, 

 is at the north end 2 feet wide and shallow, at tlie south end 1 foot wide 

 and 8 inches deep. Several other grooves almost equally marked occur 

 near this. Their direction is S. 2° E. 



A curious groove (fig. 29) comes out from under the house on the 

 southwest side and runs in a southwesterly du-ection. This is exposed best 

 in the bottom of an unused reservoir, and can be traced for a length of 

 12 feet. It is about 2^ feet wide by 10 inches deep, the greatest depth 

 being at the east side, which is overhanging, being fluted regularly like a 

 letter S. This seems to me to have been caused possibly by water run- 

 ning beneath the ice and to be a true "lapiaz," as they occur beneath the 

 ice of the Alpine glaciers. It 

 must, then, have been polished 

 by the ice at a later time. 



High up on the road to the 

 Eyrie House, on Mount Nono- 

 tuck, deep striae run S. 22° W., 

 deflected westward in the direc- 

 tion of the Easthainpton valleyj 

 wliile on the summit above broad, 

 deep grooves abound, running 

 north and south. South of the Holyoke range, at Smiths Feny, the 

 striae run S. 25° W., on trap. At Batterson's sandstone quarry, south of 

 Mount Holyoke, at E. H. Lyman's house, the fine-grained sandstone is 

 grooved and fluted and soi'atched most beautifully over a broad surface 

 (see PI. X, p. 488). The ice met the vertical and overhanging face of the 

 sandstone and fitted itself so exactly to it that scratches and polishing occm* 

 on surfaces placed at all angles to the horizon, even upon the under side of 

 projecting ridges. In the vertical westward-facing wall the basset edges of 

 the horizontal sandstone beds are polished like glass, and one thin, softer, 

 shaly bed is cut in deeply to form a long- groove lOJ inches deep and only 

 3 inches wide at the mouth, but polished to the bottom, where it is but a 

 half inch wide. The direction of the scratches is here very irregular, going 

 to all points both in altitude and azimuth. The prevalent du-ection, how- 

 ever, over the bi'oader, flatter surfaces is south. 



FlQ. 29.— t^lacial 



e on compact diabaae, Proepect House, 

 Mount Holyoke. 



