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.