and Laboratory Methods. 



15G9 



the range. The direction toward Sin-yale-a-min is almost due east, toward 

 McDonald northeast. The photographs were taken at about eleven o'clock in 

 the morning, and hence the sun is in the rear, or behind the operator. A slight 

 wind was blowing, requiring considerable time to secure the negatives. When 

 the wind blew so as to shake the instrument the cap was placed over the lens, 

 and was removed when the instrument again became quiet. 



Fig. '2 shows distinctly many features not made out in Fig. 1, and not 

 discernible to the naked eye. McDonald peak is the double peak in the left of 

 the illustration, the peak to the right being much lower, nearer, and not con- 

 nected with McDonald. The ridge extending to the left immediately in front of 

 McDonald is a separate peak, and between it and McDonald is a deep canyon 

 through which fiows a good sized stream. 



McDonald peak is plainly seen to be double. The distant peak, the right 

 hand snow-capped peak, is about a thousand feet higher than the nearer one. 



Fig. 2. — A Portion of the Range shown in Fig. 1, indicated by A. 



So far as known it has not been ascended from the side seen, and is apparently 

 inaccessible, although experience may prove it to be reached from this side. 



The strata are clearly shown. In a photograph printed lighter the details of 

 the mountain side are shown more clearly, but the snow summit is less distinct. 

 I do not know that the two peaks shown in the foreground and to the right of 

 McDonald have ever been ascended, and I have heard of no names for them. 

 In this connection I may say that land snails are living on the shoulder of 

 McDonald shown in the left. The plate used in making Fig. 2 was an ortho- 

 chromatic, with ray filter. The magnification is about eight diameters. 



The camera was next turned toward Sin-yale-a-min mountain, shown in Fig. 

 3. The conditions were precisely the same, and the position unchanged. 

 By an examination of Fig. 4, Sin-yaie-a-min mountain, the snow-capped peak 

 to the left, is seen to be double. The nearer peak is the lower, by some few 

 hundred feet. At a point half way up the peak along the ridge, snails similar to 

 to those mentioned on McDonald were found. 



By printing for detail in any one place in the negative various features may 

 be brought out with much distinctness. 



