The period of the nightingale's return throughout the greater part of Germany, is the middle of April, rarely either earlier or later[74]: it is always when the white-thorn begins to expand its leaves. Advancing slowly and gradually, these birds are not so likely to suffer from bad weather as those which go straight to their destination by one stage. In the middle of August each family prepares to depart; this is done quietly, removing gradually, and passing from grove to grove to the end of their journey; then it is that these birds are caught with nooses or springes, by using elderberries or currants for a bait. The middle of September is the latest period at which they are seen in Germany. All then disappear imperceptibly, so that the time they employ in the rest of their journey is altogether unknown. Other birds, whose instinct leads them to travel in large flights, do not so easily escape observation. If by accident a nightingale is met with at the end of September, or in October, it must have been delayed by some peculiar circumstance; for instance, it may be a young one that has lost its way, or that was hatched late, or it may be an invalid. In confinement nightingales may be allowed to fly freely, as I have often permitted them; but they do not then sing so well as when in a cage, where they are less subject to interruptions, and where also they live longer and more healthily, from being fed with more care and regularity. The nightingale's cage, of whatever form, must not be less than a foot and a half in length, by about one in width, and one or more in height. The top should be made of linen or soft stuff, that when jumping and struggling, especially when first caught, he may not injure his head. The drinking-cup and feeding-trough are fastened on the outside, unless it is preferred to introduce the latter within, in the form of a drawer. The following are the best form and proportions for a nightingale's cage, that I am acquainted with:--Length, one foot and a half; breadth, eight inches; height, fifteen inches in the middle; thirteen at the sides, because the roof is arched. The sides are made of osiers about a quarter of an inch thick; the bottom is made of the same material, but it is covered by a drawer an inch and a quarter in depth. In order to clean it more easily, I cover it with coarse paper, which I renew every time. The feeding-trough is introduced on one side, with edges high enough to prevent the bird's spilling too much of the food. In the middle of the front of the cage, and extending from top to bottom, is a cylindrical projection in the form of a belfry, in which is suspended a large drinking-glass. The upper stick of the cage is confined here, terminating in a fork, or fixed to a semi-circle, that the projection may not be prevented from moving. This projection is made of osiers,