CHAPTER VI. JOHN LE CONTE'S PHYSICAL STUDIES OF LAKE TAHOE
In certain numbers (November and December 1883 and January 1884) of the Overland Monthly, Professor John Le Conte, of the State University, Berkeley, California, presented the results of his physical studies of Lake Tahoe in three elaborate chapters. From these the following quotations of general interest are taken:
Hundreds of Alpine lakes of various sizes, with their clear, deep, cold, emerald or azure waters, are embosomed among the crags of the Sierra Nevada Mountains. The most extensive, as well as the most celebrated, of these bodies of fresh water is Lake Tahoe.
This Lake, ... occupies an elevated valley at a point where the Sierra Nevada divides into two ranges. It is, as it were, ingulfed between two lofty and nearly parallel ridges, one lying to the east and the other to the west. As the crest of the principal range of the Sierra runs near the western margin of this Lake, this valley is thrown on the eastern slope of this great mountain system.
The boundary line between the States of California and Nevada makes an angle of about 131 degrees in this Lake, near its southern extremity, precisely at the intersection of the 39th parallel of north latitude with the 120th meridian west from Greenwich. Inasmuch as, north of this angle, this boundary line follows the 120th meridian, which traverses the Lake longitudinally from two to four miles from its eastern shore-line, it follows that more than two-thirds of its area falls within the jurisdiction of California, the remaining third being within the boundary of Nevada. It is only within a comparatively recent period that the geographical coordinates of this Lake have been accurately determined.
Its greatest dimension deviates but slightly from a medium line. Its maximum length is about 21.6 miles, and its greatest width is about 12 miles. In consequence of the irregularity of its outline, it is difficult to estimate its exact area; but it cannot deviate much from 192 to 195 square miles.
The railroad surveys indicate that the elevation of the surface of its waters above the level of the ocean is about 6247 feet.
Its drainage basin, including in this its own area, is estimated to be about five hundred square miles. Probably more than a hundred affluents of various capacities, deriving their waters from the amphitheater of snow-clad mountains which rise on all sides from 3000 to 4000 feet above its surface, contribute their quota to supply this Lake. The largest of these affluents is the Upper Truckee River, which falls into its southern extremity.
The only outlet to the Lake is the Truckee River, which carries the surplus waters from a point on its northwestern shore out through a magnificent mountain gorge, thence northeast, through the arid plains of Nevada, into Pyramid Lake. This river in its tortuous course runs a distance of over one hundred miles, and for about seventy miles (from Truckee to Wadsworth) the Central Pacific Railroad follows its windings. According to the railroad surveys, this river makes the following descent:
Fall Distance Fall per Mile Lake Tahoe to Truckee 15 Miles 401 Ft. 28.64 Ft Truckee to Boca 8 " 313 " 39.12 " Boca to State Line 11 " 395 " 35.91 " State Line to Verdi 5 " 211 " 42.21 " Verdi to Reno 11 " 420 " 38.18 " Reno to Vista 8 " 103 " 12.87 " Vista to Clark's 12 " 141 " 11.75 " Clark's to Wadsworth 15 " 186 " 12.40 " Wadsworth to Pyramid Lake 18 " 187 " 10.39 " ___ ____ ____ Lake Tahoe to Pyramid Lake 103 " 2357 " 23.11 "
[Footnote 1: The elevation of Pyramid Lake above the sea-level has never, as far as we know, been accurately determined. Henry Gannet, in his Lists of Elevation (4th ed., Washington, 1877, p. 143), gives its altitude above the sea as 4890 feet; and credits this number to the Pacific Railroad Reports. But as this exact number appears in Fremont's Report of Exploring Expedition to Oregon and North California in the Years 1843-44. (Doc. No. 166, p. 217), it is probable that the first rude and necessarily imperfect estimate has been copied by subsequent authorities. This number is evidently more than 800 feet too great; for the railroad station at Wadsworth (about eighteen or twenty miles from the lake), where the line of the railroad leaves the banks of the Truckee River, is only 4077 feet above the sea-level. So that these numbers would make Pyramid Lake 813 feet above the level of its affluent at Wadsworth; which, of course, is impossible. Under this state of facts, I have assumed the elevation of this lake to be 3890 feet.]