264 SCIENCE SKETCHES. 
Divide. In the space! between this stream, which 
flows west to help form the Snake River, and a 
smaller stream now called Atlantic Creek, flowing 
down the east slope of the Divide, the great chain 
of the Rocky Mountains shrinks to a narrow pla- 
teau of damp meadow, not a fourth of a mile in 
width; and some years, when the snows are heavy 
and melt late in the spring, this whole region is 
covered with standing water. The trout had bided 
their time until they found this pass, and now they 
were ready for action. Before the water was 
drained they had crossed the Divide and were de- 
scending on the Atlantic side toward the Yellow- 
stone Lake. As the days went by, this colony of 
bold trout spirits grew and multiplied and filled 
the waters of the great clear lake, where their de- 
scendants remain to this day. And no other fishes 
—not the chub, nor the sucker, nor the white-fish, 
nor the minnow, nor the blob — had ever climbed 
Pacific Creek. None of them were able to follow 
where the trout had gone, and none of them have 
ever been seen in the Yellowstone Lake. What 
the trout had done in this lake — their victories 
and defeats, their struggles with the bears and 
pelicans, and with the terrible worm, joint enemy 
of trout and pelicans alike — must be left for 
another story. 
So the trout climbed the Yellowstone Falls by 
way of the back staircase. Having once reached 
its top, it was easy to go down it on the other side. 
And in a similar way, by stealing over from Black- 
1 For a detailed account of “ Two-Ocean Pass,” see Evermann, 
Popular Science Monthly, June, 1894. 
