We could not have a more pleasant day, children, for a ramble in the fields than to-day. It is warm and bright, and the birds are singing merrily, thoroughly enjoying the sunshine; the little lambs are frisking about, and running races with each other. Put away lessons then, and we will have a holiday. "Oh," said Willy, "it will be so pleasant, and I will take one or two bottles, and my gauze net, because we are sure to find something interesting to bring home. Where shall we go?" "I do not think it much matters where, for there is always much to observe and to admire wherever we stroll in the country." "Let us go on the moors, then," said Jack, "for you know, papa, a little boy in the village told me the other day he had found a peewit's nest with four eggs in, and I should like to try and find one myself." Well, here we are, then; we shall have to jump over a drain or two in our ramble, and as the banks are soft it will be necessary to take great care, or we may tumble in. Ah! do you see, there are two sand-martins, the first I have seen this year. See how fast they fly, now sailing high up in the air, now skimming quite close to the ground. I have not seen any swallows or house-martins yet, but no doubt they will make their appearance in a few days. "Where do they come from, papa," asked May, "because we never see these birds in the winter? You often say, when the spring comes we shall see the swallows, and then they go away again towards the end of summer." Let us sit down on this clump of wood, and I will tell you about the swallows.