392 GEOLOGICAL EXCURSION TO THE ROCKY MOUNTAINS.. 



never used for that purpose; and Zion's Cooperative Mercantile Insti- 

 tution, the headquarters of a commercial system organized and con- 

 ducted by the church. 



Polygamy, which was formerly enjoined by the church upon its mem- 

 bers as a duty, has, after long and bitter conflict "with the United 

 States Government, been abandoned. 



The system of irrigation can be conveniently examined in the sub- 

 urbs of the city. 



Fault scarps near the Thermal springs. — Along the base of a great 

 range like the Wasatch a vast amount of alluvium is deposited. On 

 the steep slopes of the mountain gorges erosion is rapid, and the result- 

 ing detritus is rolled forward by the torrents and deposited on the plain 

 outside the line of mountain front. Between the canyon mouths the 

 waste from the mountain face produces talus, and this combines with 

 the alluvium in the formation of a sloping apron of debris. In the case 

 of the Wasatch range this tendency is part ially counteracted by progres- 

 sive movement along the great fault line which everywhere bounds the 

 range. From time to time the mountain block rises, and the adjacent 

 part of the valley block, with its load of detritus, sinks, and the height 

 of the alluvial slope is thus diminished. 



Near the Warm springs there is a point where the vertical rock face 

 of the mountain is laid bare and the valley alluvium meets it as a hor- 

 izontal plain instead of a foot slope. A few feet up the rock cliff a line 

 of adhering cement marks former contact with the alluvium, the sepa- 

 ration being presumably due to a recent fault. Nearby, the alluvium 

 is locally disposed in a series of Steps marking details of displacement. 

 A little farther northward between the Warm springs and the Hot 

 springs, a symmetrical cone of alluvium is built upon the valley plain, 

 and recent faulting has dropped one portion of this cone below another 

 so that their relations can be clearly seen. The flood plain of the wet- 

 weather stream descending the alluvial cone shows a series of terraces 

 of different heights, illustrating the fact that the fault scarp was pro- 

 duced by a number of successive movements. 



Garfield. — Garfield is a bathing resort on the shore of Great Salt lake, 

 and will be visited in order to give members of the party an opportu- 

 nity to bathe in the lake, and to examine the terraces and cliffs of 

 Lake Bonneville. 



The brine of the lake lias a density at the present time of about 

 145, and its consequent buoyancy gives a new sensation to the bather. 

 He readily floats, with head, feet, and hands out of the water. In 

 swimming he is annoyed by the tendency of his feet to rise to the sur- 

 face, and if he brings them beneath him so as to assume an erect posi- 

 tion in the water, he finds not only his head but Ins shoulders above 

 the surface. 



