WATER SUPPLY. 67 
estimate the old mean area at 1,820 miles, the new at 2,125 miles, and the 
increase at 305 miles, or 17 per cent. 
The “abnormal change” of the lake may then be described as an 
infilling or rise of the water whereby its ordinary level has been raised 7 
or 8 feet and its ordinary area has been increased a sixth part; and this 
appears to be distinct from the limited oscillation and annual tide, which 
may be regarded as comparatively normal. ‘To account for it a number of 
theories have been proposed, and three of them seem worthy of considera- 
tion. They appeal respectively to volcanic, climatic, and human agencies. 
VOLCANIC THEORY. 
It has been surmised that upheavals of the land, such as sometimes 
accompany earthquakes, might have changed the form of the lake bed and 
displaced from some region the water that has overflowed others. This 
hypothesis acquires a certain plausibility from the fact that the series of 
uplifts and downthrows by which the mountains of the region were formed 
have been traced down to a very recent date, but it is negatived by such an 
array of facts that it cannot be regarded as tenable. In the first place, the 
water has risen against all the shores and about every island of which we 
have account. The farmers of the eastern and southern margins have lost 
pastures and meadows by submergence. At the north, Bear River Bay has 
advanced several miles upon the land. At the west, a boat has recently 
sailed a number of miles across tracts that were traversed by Captain 
Stansbury’s land parties. That officer has described and mapped Strong's 
Knob and Stansbury Island as peninsulas, but they have since become 
islands. Antelope Island is no longer accessible by ford, and Egg Island, 
the nesting ground of the gulls and pelicans, has become a reef. Springs 
that supplied Captain Stansbury with fresh water near Promontory Point 
are now submerged and inaccessible ; and other springs have been covered 
on the shores of Antelope, Stansbury, and Fremont islands. ; 
In the second place, the rise of the lake is correlated in time with the 
increase of the inflowing streams, which has been everywhere observed by 
irrigators, and it is logical to refer the two phenomena to the same cause. 
And, finally, if upheaval could account for the enlargement of the 
lake, it would still be inadequate to account for the maintenance of its 
