24 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 
20, 1901, when reviewing Spurr’s paper on the Origin and Structure 
of the Basin Ranges. The diagram was not intended to be a picture 
of any actual range, for at that time I had not gained any personal ac- 
quaintance with the Basin ranges. It was simply designed to show an 
imaginary block of various structures, that had been faulted, uplifted 
and submaturely carved; it was a graphic summary of the conse- 
quences reasonably deducible from the theory of the block-faulting of 
the Basin ranges. When the essential features of such a diagram 
are found in nature, one may fairly conclude that the consequences 
of the theory, summarized in the diagram, are correctly deduced, 
TN 
y | 
ih 
Il 
i | 
i iin | 
IM 
r 
Fig. 8.— Diagram of a mountain carved on a faulted block of previously de- 
formed and denuded strata; reprinted from Science, Sept. 20, 1901. 
and that the theory from which such consequences are deducible 
furnishes the true explanation for the observed facts which corre- 
spond to the inferred consequences. 
We spent the night of July 14 at Nephi. Here the Wasatch range 
proper may be said to end, for the deep and wide valley of Salt creek 
comes after the Mt. Nebo mass. The valley comes in from the 
northeast, apparently the result of easy erosion on the next follow- 
ing Permian clays, which are everywhere very weak in the Plateau 
province. Beyond the oblique valley is an oblique ridge, trending 
northeast-southwest, like those already described; and rising behind 
it (southeast) was a still higher oblique ridge or escarpment with bold 
red cliffs, presumably of the Trias. The Wasatch fault therefore 
probably continues southward, but our turn westward the next day 
gave us no further sight of it. 
