Adapted from "The Colors of Animals" by Sir John Lubbock in A Book of Natural History (1902, ed. David Starr Jordan)

The color of animals is by no means a matter of chance; it depends on many considerations, but in the majority of cases tends to protect the animal from danger by rendering it less conspicuous. Perhaps it may be said that if coloring is mainly protective, there ought to be but few brightly colored animals. There are, however, not a few cases in which vivid colors are themselves protective. The kingfisher itself, though so brightly colored, is by no means easy to see. The blue harmonizes with the water, and the bird as it darts along the stream looks almost like a flash of sunlight.

Desert animals are generally the color of the desert. Thus, for instance, the lion, the antelope, and the wild donkey are all sand-colored. “Indeed,” says Canon Tristram, “in the desert, where neither trees, brushwood, nor even undulation of the surface afford the slightest protection to its foes, a modification of color assimilated to that of the surrounding country is absolutely necessary. Hence, without exception, the upper plumage of every bird, and also the fur of all the smaller mammals and the skin of all the snakes and lizards, is of one uniform sand color.”

The next point is the color of the mature caterpillars, some of which are brown. This probably makes the caterpillar even more conspicuous among the green leaves than would otherwise be the case. Let us see, then, whether the habits of the insect will throw any light upon the riddle. What would you do if you were a big caterpillar? Why, like most other defenseless creatures, you would feed by night, and lie concealed by day. So do these caterpillars. When the morning light comes, they creep down the stem of the food plant, and lie concealed among the thick herbage and dry sticks and leaves, near the ground, and it is obvious that under such circumstances the brown color really becomes a protection. It might indeed be argued that the caterpillars, having become brown, concealed themselves on the ground, and that we were reversing the state of things. But this is not so, because, while we may say as a general rule that large caterpillars feed by night and lie concealed by day, it is by no means always the case that they are brown; some of them still retaining the green color. We may then conclude that the habit of concealing themselves by day came first, and that the brown color is a later adaptation.

Adapted from “The Stars” by Sir Robert S. Ball in Wonders of Earth, Sea, and Sky (1902, ed. Edward Singleton Holden)

The group of bodies that cluster around our sun forms a little island in the extent of infinite space. We may illustrate this by drawing a map in which we shall endeavor to show the stars placed at their proper relative distances. 

We first open the compasses one inch, and thus draw a little circle to represent the path of Earth. We are not going to put in all the planets; we take Neptune, the outermost, at once. To draw its path, I open the compasses to thirty inches, and draw a circle with that radius. That will do for our solar system, though the comets no doubt will roam beyond these limits. 

To complete our map, we ought to put in some stars. There are a hundred million to choose from, and we shall begin with the brightest. It is often called the Dog Star, but astronomers know it better as Sirius. Let us see where it is to be placed on our map. Sirius is a good deal further off than Neptune; so I try at the edge of the drawing-board; I have got a method of making a little calculation that I do not intend to trouble you with, but I can assure you that the results it leads me to are quite correct; they show me that this board is not big enough. But could a board which was big enough fit into this lecture theatre? No; in fact, the board would have to go out through the wall of the theatre, out through London. Indeed, big as London is, it would not be large enough to contain the drawing-board that I should require. It would have to stretch about twenty miles from where we are now assembled. We may therefore dismiss any hope of making a practical map of our system on this scale if Sirius is to have its proper place. 

Let us, then, take some other star. We shall naturally try with the nearest of all. It is one that we do not know in this part of the world, but those that live in the southern hemisphere are well acquainted with it. The name of this star is Alpha Centauri. Even for this star, we should require a drawing three or four miles long if the distance from the earth to the sun is to be taken as one inch. 

You see what an isolated position our sun and its planets occupy. The stars might be very troublesome neighbors if they were very much closer to our system; it is therefore well they are so far off. If they were near at hand, they would drag us into unpleasantly great heat by bringing us too close to the sun, or produce a coolness by pulling us away from the sun, which would be quite as disagreeable.