NO. II THE FRESHFIELD GLACIER — PALMER 3 



ing the valley bottom, and of the sharp peak of Mt. Freshfield 

 (10,945 feet) rising over it in the background five miles away. 

 Around the trunk of an evergreen tree on the edge of the bank a 

 white band was painted to serve as a station in the instrumental 

 triangulation. A stream of clear water lies at the foot of the bank. 



After a trip up the three-mile tongue, a suitable location, 1,250 

 yards above the end of the glacier, was chosen for establishing a line 

 across the surface of the ice. The mark for the northern end was a 

 rectangular slab of rock a rod square, perched on the inner slope of 

 the north lateral moraine 50 yards above the glacier. It is one of the 

 most prominent boulders anywhere on that side of the valley and is 

 visible from nearly all parts of the northern half of the lower glacier. 

 It is also visible from Camp Station, being about one and one-quarter 

 miles distant therefrom. It is tilted towards the glacier and is the 

 largest stone to be seen near the top of the lateral moraine from that 

 standpoint. It is designated Station A. Owing to lack of time it 

 was not painted. The mark for the southern end of the line was a 

 much smaller boulder 125 feet above the edge of the ice on the 

 crest of the south lateral moraine near the base of a prominent gully 

 that scars the valley wall. A vertical reference line was painted 

 on the side towards the glacier. It is designated Station B. 



On July 13, Station A was occvipied with the instrument. Four- 

 teen numbered flat stones were carried out on the glacier and set in 

 flat-bottomed niches chipped in the ice, 50 paces apart, on the line 

 indicated by the vertical hair of the telescope, in accordance with 

 signals from the observer. Such stones, particularly if dark in 

 color, have a tendency to become fixed in the ice through melting. 

 The writer has set out three of these lines, and has never had reason 

 to suspect that any stone slipped from its original position. If one 

 side of the stone is straight, it gives a good fiducial edge upon 

 which to sight with the instrument. The azimuth and angle of 

 depression of each stone were determined from a second station on 

 the north moraine, later ascertained to be 320 feet distant. On line 

 A-B the ice was 1,133 yards w'ide. 



The positions of the stones are shown on the accompanying cross- 

 section of the glacier (fig. i). The estimated thickness of the ice is 

 based upon the assumption that the gradient of the valley floor obtain- 

 ing below the forefoot continues uniformly back under the ice. 

 According to the configuration of the valley hereabouts, this does 

 not seem unwarranted. The slope is about 125 feet to the mile and 

 the maximum thickness of the glacier at the line of stones works 



