The tender little minnows that bask in the sunny shallows of the river have never even seen the sea, their ancestors left it so long long ago; yet to them, too, water is life and breath and everything. The green meadow through which the river flows is just the border of their world and nothing more, and the air is boundless space, which they never visit except for a moment to snap at a tiny fly, or when they jump up to escape the jaws of some bigger fish. Every one knows the minnow, and we cannot do better than take him as our type of a fish in order to understand how they live and move and breathe. Go and lie down quietly some day by the side of the clear pebbly shallows of some swiftly-flowing river where these delicate little fish are to be seen; but keep very still, for the slightest movement is instantly detected. There they lie
“Staying their wavy bodies ’gainst the streams
To taste the luxury of sunny beams
Tempered with coolness. How they ever wrestle
With their own sweet delight, and ever nestle
Their silver bellies on the pebbly sand!
If you but scantily hold out the hand,
That very instant not one will remain;
But turn your eye and they are there again.”
Fig. 4.