But the squirrel did not return the farewell, for when he saw the very ridiculous manner in which his friend shuffled along, while he performed the feat which he called running, he was seized with such a fit of laughter that he could make no reply, and he was even obliged to hold fast, lest he should fall off the branch. When he had recovered from his merriment, he began to talk to himself, in an unusually grave and moralizing strain.
"Well, Mr. Leatherwing," said he, "you are an odd fellow, a very odd little fellow indeed! But I have learned something from you this evening, besides the information you gave me about those rats. I have learned that every animal has a different part to perform in the world, and that we all should be content with our situations, and not attempt to do things for which we were never intended. Now I suppose nobody will deny that I can run and leap famously, so that I am quite at home among the boughs of this beautiful oak; but I cannot fly at all, and I believe I should be a very poor swimmer. Then there is my neighbour, the water-rat, who can both dive and swim like a fish, but he can no more fly than myself, and I am sure he cannot leap half so well. As for old Leatherwing, the air is for him, and most delightful it must be to fly and sail about as he does. But then he must be content with flying only, for I think he would be much worse off in the water than I should, and when he attempts to run or to leap—Ha! ha! what fun! I must go and tell Mrs. Brush all about that."
[ 4 ] The membrane of the bat's wing appears to possess a most exquisite and inconceivable sensibility. Cruel experiments have proved that this animal, when deprived of the senses of seeing, hearing, and smelling, will still fly about a room, without ever coming into contact with the walls, or with threads stretched across in all directions. Cuvier supposes, that "the propinquity of solid bodies is perceived by the manner in which the air re-acts upon the surface of the wings." This astonishing faculty, which almost indicates the possession of a sixth sense unknown to us, is no doubt of great use to the bat, as it enables him to pursue his rapid zigzag flight in the dark, without fear of striking against the boughs of trees, or other obstacles.
The animal introduced in the tale is the common bat, Vespertilio pipistrellus of modern naturalists. It is now ascertained that no less than seventeen species of this singular family are natives of this country. Some of them are very much larger than the common bat, measuring fifteen inches in the extent of their wings.
[ 5 ] The common brown rat, which has now been an inhabitant of this island for about one hundred years, is often improperly called the "Norway rat," as if it came originally from that country; whereas, it was quite unknown there when it first received that name. Pennant believes that it was brought over in merchant-vessels from the East Indies.
It is even supposed, that the old English black rat, as it is called, is not originally a native of this island, as no mention is made of it in any author earlier than the middle of the sixteenth century.