|
|
Dividend Two Directory 14
Page 04
In No. 3 the nest is seen full of eggs, and the excellent father now comes out in his best light as their guardian and protector. He watches over them with ceaseless care, freeing them from parasites, and warding off the attacks of would-be enemies who desire to devour them, even though the intruder be several times his own size. The spines on his back here stand him once more in good stead: for small as he is, the stickleback is not an antagonist to be lightly despised: he can inflict a wound which a perch or a trout knows how to estimate at its full value. But that is not all the good parent's duty. He takes the eggs out of the nest every now and then with his snout, airs them a little in the fresh water outside, and then replaces and rearranges them, so that all may get a fair share of oxygen and may hatch out about simultaneously. It is this question of oxygen, indeed, which gives the father fish all the greatest trouble. That necessary of life is dissolved in water in very small quantities; and it is absolutely needed by every egg in order to enable it to undergo those vital changes which we know as hatching. To keep up a due supply of oxygen, therefore, the father stickleback ungrudgingly devotes laborious days in poising himself delicately just above the nest, as you see in No. 3, and fanning the eggs with his fins and tail, so as to set up a constant current of water through the centre of the barrel. He sits upon the eggs just as truly as a hen does; only, he sits upon them, not for warmth, but for aeration.
This way of measuring does not, however, take us very far away in the heavens. There are only a few hundred stars within five hundred trillion miles of the earth, and at that distance the "shift" of a star against the background (parallax, the astronomer calls it) is so minute that figures are very uncertain. At this point the astronomer takes up a new method. He learns the different types of stars, and then he is able to deduce more or less accurately the distance of a star of a known type from its faintness. He, of course, has instruments for gauging their light. As a result of twenty years work in this field, it is now known that the more distant stars of the Milky Way are at least a hundred thousand trillion (100,000,000,000,000,000) miles away from the sun.
There is an old and strange Eastern allegory of a man wandering in the desert; he draws near to a grove of trees, when he suddenly becomes aware that there is a lion on his track, hurrying and bounding along on the scent of his steps. The man flees for safety into the grove; he sees there a roughly built water-tank of stone, excavated in the ground, and built up of masonry much fringed with plants. He climbs swiftly down to where he sees a ledge close on the water; as he does this, he sees that in the water lies a great lizard, with open jaws, watching him with wicked eyes. He stops short, and he can just support himself among the stones by holding on to the branches of a plant which grows from a ledge above him. While he thus holds on, with death behind him and before, he feels the branches quivering, and sees above, out of reach, two mice, one black and one white, which are nibbling at the stems he holds and will soon sever them. He waits despairingly, and while he does so, he sees that there are drops of honey on the leaves which he holds; he puts his lips to them, licks them off, and finds them very sweet.
|