=Broody hens.= When a hen wants to incubate eggs, or, as the common phrase is, to sit, she remains on her nest continuously and, unless very shy, will not leave it when approached and will resent any interference. The hen is then said to be broody. Because the broody hen makes a clucking noise, she is sometimes called a clucking hen. Hens that are shy when they begin to cluck, and that fly from the nest when approached, usually become tame and allow themselves to be handled after a few days. Broody hens cannot always be obtained at the time they are wanted. In that case there is nothing to do but wait, or try to buy, hire, or borrow them. There is no way of forcing or inducing hens to become broody before they would do so of their own accord. When broody hens are hard to get, people think that hatching with incubators will relieve them of trouble and prevent delay, but the incubator, too, has its uncertainties. Success in artificial hatching requires careful attention to the operation of the incubator and good judgment in adjusting and regulating it. [Illustration: Fig. 91. Nest boxes, made in pairs, for sitting hens. Inside dimensions: large, 16" × 16" × 18"; small, 12" × 12" × 15"] [Illustration: Fig. 92. Same as Fig. 91, with nest boxes closed] =Setting the hens.= As many broody hens as can be obtained should be set at the same time. The most convenient style of nest is that shown in Figs. 91 and 92, which can be kept closed if desired. The best nest material is soft hay or straw. In preparing the nest a poultry keeper shapes the nest material with his hand, to give it a bowl shape, pressing it down to make a smooth, firm surface upon which the eggs will lie evenly. It is a good plan to make the nests and place the hens in them, giving to each a few China nest eggs two or three days before the eggs that are to be hatched are given to them. The eggs for hatching should be of good size and shape, with good strong shells, and as uniform in color as can be obtained. The usual number of eggs placed under a hen is thirteen. After the weather becomes warm, even a small hen will cover thirteen eggs well, and medium-sized hens will cover fifteen or sixteen eggs and often hatch every one, but early in the season it is better to give a hen eleven eggs or perhaps only nine. The number of eggs given a hen is almost always an odd number. There is an old superstition that an even number will not hatch. The reason commonly given by writers on poultry is that an odd number of eggs arrange in better form in the nest, but this is mere fancy. However the practice started, the real reason why odd numbers of eggs are placed in nests of sitting hens now is that the custom is so well established, and the habit of thinking of eggs for hatching in odd numbers is so strong, that most poultry keepers do it unconsciously.