Shortly after this episode one of our helpers in the office found a nest of mice, and, mindful of my hungry snakes, I contrived to catch one mouse alive. When the rattlers saw him through their screen, they manifested such a lively interest as nothing had aroused in them before. I cautiously opened the slide in the top of the cage, held the mouse up by the tail, and let him drop. There was a fair illustration of the matchless agility of the crotalus when he cares to be quick. The cage was just twelve inches high in the clear; but before the falling mouse was halfway to the bottom, there was an indescribable gray blur, and I knew that the larger snake had hit him. I have improved numerous chances to study the stroke of rattlesnake, which is the swiftest motion made by any living creature; but that particular case, better than any other, gave me a conception of its actual rapidity. From years of experience with the pneumatic shutter in photographing objects in rapid motion, I should say the snake's head traversed that twelve or fifteen inches in something like the three-hundredth part of a second. The mouse fell upon the floor of the cage, and it never moved again. The snake knew perfectly that it had done its work, for in place of "recovering" for another stroke, as they invariably do after a failure, he swallowed the mouse in the usual slow and painful fashion, with as much apparent effort as a morsel four times as large should have given him. HARD TO HIT By Ernest Ingersoll The spring weather we sometimes have in March reminds me, especially in the evening, of some days passed so high up in the Rocky Mountains that the summer was left down in the valley. One such spring-like evening we camped close to the timber-limit, and I made my first trip into the region above, in which no trees grow. Having left the spruce-woods quickly behind, there came some stiff climbing up ledges of broken rocks, standing, cliff-like, to bar the way to the summit. These surmounted, the way was clear, for from the northeast--the side I was on--this mountain presents a smooth grassy slope to the very top; but the western side of the range is a series of rocky precipices, seamed and shattered. This is true of many mountains in Colorado. Just above the cliffs grew a number of dwarfed spruces, some of them with trunks six inches in diameter, yet lying flat along the ground, so that the gnarled and wind-pressed boughs were scarcely knee-high. They stood so closely together, and were so stiff, that I could not pass between them; but, on the other hand, they were strong enough to bear my weight, so that I could walk over their tops when it was inconvenient to go around.