Tracing up the small smith, I found it busy on the trunk of an old Scotch fir, where it found, if not ants, a colony of some other small insects, for it was picking them off right and left as they fled along the bark. This bird has discovered that if it raps upon a bough, the insects in the crevices are startled from their hiding-places by the jarring, and rush out, like human beings after an earthquake shock, into the open air, where the nuthatch soon disposes of them; and, unless I am mistaken, it is the only British bird that arrives at its food by a deliberate guile. All others, I think, catch their food by chancing to find it abroad, but the nuthatch accomplishes the effect by a reasonable cause, and frightens out of their chinks the creatures that it wishes to capture. Sometimes the insects only scuttle from one refuge into another, but the nuthatch rips the bark off in flakes and pursues the poor wretches from covert to covert. It takes its name from another peculiarity, its fondness for nuts, beech-mast and acorns, which it fixes tight into some little crevice in the bark and hammers open. Looking at the shells of hazel-nuts that it has cracked, I believe that it first pecks a hole, and then getting its beak into it crosswise to the natural cleavage of the shell, splits the nut with a sharp rap on the bark. Its beak enters like a wedge and, while the two half-shells drop to the ground, one on either side, pierces and holds the kernel. It must take it out of its vice to split it, for while tightly gripped the bird could only pierce a hole in the nut and not cleave it, and this is evident if we put the two halves together, for we then see that though a hole was made, the shell did not split. The bird had to take it out of the cleft on its beak and knock it on the tree. When nesting, it is not content with a hole that just suits it in size, but must needs choose a large hole and then plaster it up with mud till it becomes small enough. With the rest of the animal world the rule is to select what fits them at first, and failing this to enlarge the house to their needs. But the nuthatch has sense on its side, for it is easier to reduce than to increase, and which of us, if the sizes of houses made no difference in their rents, would not occupy by preference tenements with what auctioneers call "commanding approaches," and "noble entrance halls," even if we only used the back-door to come in and go out at? So the nuthatch picks out a big hole and then reduces it to its own dimensions, and the little nuthatches no doubt, when the tree-creepers happen to come by, speak boastfully of "the woodpecker's house" that they live in, but never say that they keep the great front-doors shut and get in and out by the scullery-window.