With tirings there will often be a small quantity of castings which will be swallowed with the pickings of meat. The trainer must judge for himself whether enough of them has been thus taken during the day to form a proper pellet, or whether more should be given in another way. In feeding up upon quarry which they have themselves killed, whether on the fist or on the ground, hawks will almost always naturally take castings enough. But when the meal consists of beef, or of anything that has been skinned or plucked quite bare, it will be necessary either to add some feathers or fur, or the like, scattering it about on the meat which the hawk is about to swallow, or else the casting may consist of a strip of skin with fur or feathers left on it, and a piece of meat at one end. While swallowing the meat the hawk will gulp down the skin attached to it, and thus with one or two mouthfuls give herself the required quantity of castings. Some falconers make up the casting into a sort of pill, and cram their hawks with it; and I believe this plan answers the purpose very well, though I have seldom if ever tried it. It is not, of course, necessary to give castings every day. But they are generally beneficial, and always, as far as I know, harmless. Some of the old falconers advise not to give castings on days when a hawk has bathed; but I am unable to give the reason for this. Castings are taken daily by wild hawks, which certainly have less need of them than tame ones. And if, through laziness or any other cause, the falconer omits for days in succession to give any, it is pretty certain that his hawk's crop and stomach will become clogged with a sort of mucus, which will either make her dull, sluggish, and morose, or otherwise impair her general health. Castings should be given rather late in the day than early; and after they have been taken the hawk must always be kept unhooded at about the time when she may be expected to throw them up, _i.e._ from about the fifth hour after she has swallowed the casting, until she has cast. For this reason, if for no other, when it is intended to train passage hawks in any place, it must always be possible to darken artificially a part of the room, so that hawks can sit there bareheaded on the perch after castings have been given.