74 APPENDIX TO REPORT OF THE SECRETARY. 



The locality was then a popular pleasure resort, and tlie record was 

 undertaken by Mr. J. T. Mitchell. Observations were made at frequent 

 intervals for more than a year, but were then interrupted by reason of 

 the disuse of the locality as a place of resort, and they have not since 

 been resumed in a systematic way. To obviate a similar difiQculty in 

 the future, Mr. Gilbert caused a new record-post to be established near 

 the town of Farmington, where the work of observation has been un- 

 dertaken by Mr. Jacob Miller, and it is anticipated that in the future 

 there will be no break in the continuity of the record. 



In the interval from 1847 to 1875, during which no direct observations 

 were made, there was nevertheless a considerable amount of indirect 

 observation incidental to the pursuits of the citizens. The islands of 

 the lake were used for pasturage, and the facilities for the transfer of 

 cattle to and fro were greatly affected by the fluctuations of the water. 

 A large share of the communication was by boat, and the frequent 

 changes of landing-place which the boatmen were compelled to make 

 impressed upon their memories the character and order of the principal 

 oscillations. In pursuance of the inquiries instituted by the Secretary 

 of the Smithsonian Institution, the testimony of the boatmen was com- 

 piled by Mr. Jacob Miller, and a history of the oscillations was deduced. 



A similar and corroborative history has been derived by Mr. Gilbert 

 from an independent investigation. Two of the islands used for pastur- 

 age are joined to the main-land by broad, flat bars, and during the lower 

 stages of the lake these bars, being either dry or covered by a moderate 

 depth of water, have afforded means of communication. It happens 

 that the Antelope Island bar was in use until 1865, when it became so 

 deeply covered that fording on horseback was impracticable; and that 

 the Stansbury Island bar was first covered with water in 1866, and has 

 been used as a ford with slight exception ever since. By the compila- 

 tion of the testimony of those who have made use of these crossings, a 

 continuous record was derived which cannot deviate very widely from 

 the truth, and the work was checked by making careful soundings to 

 ascertain the present depth of water on the Antelo[)e Island bar. 



From 1817 to 1850 there was little change beside the annual tide — a 

 variation dependent upon the spring floods, and which makes the sum- 

 mer stage in each year from one to two feet higher than the winter. 

 Then the water began to rise, and so continued until in 1855 and 1856 its 

 mean stage was four feet higher than in 1850. This progressive rise was 

 followed by a progressive fall of equal amount, and in 1860 the lake had 

 returned to its first-observed level. In 1862 there began a second rise, 

 which continued for eight years, and carried the water ten feet above the 

 original level. Since 1869 there has been no great change, but the mean 

 height has fluctuated through a range of about two feet. 



As the lake has risen it has encroached upon the land, and the shores 

 are in many places so flat that large areas have been submerged. At 

 one point the water edge has advanced 15 miles, and the surveys of Capt. 



