294 6r. K. Gilbert — Inculcation of Scientific Method. 



ionally regarded as a disturbing factor merely, and the defor- 

 mation demonstrated by the measurements of shore-height was 

 treated as simply flexural or undulatory. 



To classify the shore-heights, as a basis for further hypoth- 

 esis, they were platted on a map, and their grouping was com- 

 pared with geographic features. It appeared that the highest 

 measured points lay within the area of the main body of Lake 

 Bonneville, that the lowest points lay at the extreme north and 

 at the extreme south, that the eastern shore of Lake Bonneville 

 in the vicinity of Great Salt Lake was intermediate in height, 

 and that the single point determined on the western shore of the 

 old lake agreed in height with the eastern shore. Unfortu- 

 nately, the distribution of the measurements, which had been 

 largely determined by the distribution of railroad lines, was 

 not equable throughout the basin of the lake, and nearly the 

 whole of its western shore was undetermined in altitude. 

 When lines of equal altitude were drawn among the figures 

 representing measurements, after the manner of the isobars on 

 a Signal Service weather map, it was found that they were not 

 fully controlled by the determined points; but when they had 

 been given the most satisfactory adjustment, they contoured a 

 figure of deformation which may be characterized as a low, 

 broad dome, having its crest over the center of the main body 

 of Lake Bonneville, and extending a subordinate member to 

 the region of the southern body of the lake. One half of 

 this figure was fairly inferred from the data of observation ; 

 the remaining half was imaginary and its drawing merely gave 

 graphic expression to the hypothesis suggested by the incom- 

 plete contours — the hypothesis that the deformation stands in 

 some necessary or causal relation to the lake and its disap- 

 pearance. 



Now it has been independently determined that the cause of 

 the lake and the cause of its disappearance were climatic ; it 

 was not drained by the wearing down of its outlet, nor emptied 

 by the unequal uplift of portions of its rim, but it was dissi- 

 pated by evaporation. If then the disappearance of the lake 

 and the deformation of the land are connected in a causal way 

 the change in the lake *was the cause, and the change in the 

 land was the effect. How can we suppose the drying up of the 

 water to have produced the up-arching of the plain on which 

 the water lay ? 



In the attempt to answer this question three tentative expla- 

 nations were suggested, and these will be stated in the order of 

 their origination. 



It is well known to geologists that in several instances a 

 great formation thousands of feet in thickness consists wholly 

 or chiefly of shore deposits. To account for them it is neces- 



