588 KANSAS CITY REVIEW OF SCIENCE. 



have found some color for this fancy in the variety of natural objects of nature's 

 energies so liberally found in these two Territories. 



Idaho Territory is a veritable " Phlegraean Field." My unknown friends of 

 the Academy can imagine a vast flat plain, covered from the foot of the moun- 

 tain ranges of Eastern Idaho for several hundred miles west with an uniform 

 close covering of sage brush — the Artemisii tridentata of botanists, or, as the 

 Canadian voyagers three quarters of a century since called it, '^absinthe." This 

 gives an uniform dull gray tint of inconceivable melancholy to what in other re- 

 spects would often be charming and picturesque. From this plain, formed 

 wholly of lava, covered with a thin coat of sand, and still scantier stratum of 

 vegetable soil, which, however, is generally absent, and nothing grows upon this 

 sterile surface but cactus and artemisia. 



The lava plain of Idaho is seamed in a few places by some unimportant 

 streams, the major part of them emptying into Snake River, or its main affluent, 

 Henry's Fork. Aside from this, universal drouth prevails, and 90 looths of 

 Idaho is doomed to eternal sterility. Universally, all the rivers and smafler 

 creeks flow in deep crevices in black honey combed lava, abounding in rapids 

 and deep pools of cool, clear water, and in magnificent trout. Snake River, the 

 main southern branch of the majestic Columbia, has cut out its bed in this dark 

 lava. It is a fine deep river, swift, impetuous and dangerous. The American 

 Falls, some seventy miles below Fort Hall, are stupendous and magnificent. 

 Here the whole water of this magnificent stream is precipitated down a step in 

 the lava field over 140 feet high. 



In the course of our exploration, when surveying our return line by the val- 

 ley of Madison Fork and Fire Hole River, we left the last named stream on our 

 left, and to avoid its steep and tangled canons, we prolonged our line of survey 

 over the main Rocky Mountain range by Raynolds' Pass to Henry's Lake, the 

 source of Henry's Fork of Snake River. From this lake we turned sharply east- 

 ward, crossed the Rocky Mountains by the Tahgee Pass, 7470 feet above the sea, 

 and reached Fire Hole Valley and the marvelous geysers of the National Park 

 by an easy natural wagon road. 



Fire Hole River, from the west edge of the National Park to the several 

 geyser basins, flows through a valley cut through lofty, picturesque, but ragged 

 trachyte mountains, covered with scrub pines, with glades interspersed, clothed 

 with scanty grass. The first canon in the National Park is grand and weird, ■ 

 seamed with traces of recent volcanic action. Its wildness was rendered more 

 salient from our continued watch night and day to prevent surprise from small 

 bands of hostile Indians driven eastward by Gen. Howard's campaign against 

 the Piutes and Bannocks. With some labor, and by vigorous exertion, we car- 

 ried our line of reconnoissance up to the Upper Geyser Basin, our wagons being 

 the second only that had penetrated to that point. 



I confess that my ideas are barren and ray mind bewildered by the amount 

 of objects that three days exploration of that extraordinary region developed. 

 We were then in the first days of October. Before reaching the geyser region. 



