June-August 1878, Geodetic Survey from Sacramento to Wasatch Mountains, Utah Image 33

62 [sketch: Architectural outline of mtns [mountains] looking [W] from San Antonia Range uniting with Toeyabe in the S.] The mountains in general are made of perishable material & are rapidly being decomposed & disintegrated. Even the granite is not at all enduring It seems to be beaten to pieces by the sun. 2nd. The streams that succeeded the glaciers not only swept down the disintegrated material thro [through] the main canons & out into the plain [but also] as fast as it was brought down from the heights above them but also cut narrow crooked gorges into the bed rock leaving them inaccessible to horses But the Nevada streams though once so powerful are now dwindled to mere rills or have 63 become extinct excepting during sudden thunder showers. 3rd These sudden storms locally known as cloudbursts acting only at long intervals sweep down great quantities of disintegrated material into the canons from the steeper tributaries & hillsides – a greater quantity than the torrent can carry off out the wider & leveler main canon Much of this material is therefore left outspread on the canon floor filling the rock hollows & equalizing the grade & moreover the wide leveling grading action of the sudden floods is not subsequently modified by the smaller streams by being cut into because they usually cease at once or nearly so for by far the greatest number of the cans [canons] are absolutely dry throughout their whole length. The perennial streams being confined to thehttps://scholarlycommons.pacific.edu/jmj-all/2272/thumbnail.jp