"Boxes, of which every carpenter knows the form," says Mowbray, "are to be arranged round the walls, and it is proper to have a sufficient number, the hens being apt to dispute possession, and sit upon one another. The board or step at the entrance should be of sufficient height to prevent the eggs from rolling out. Provision of a few railed doors may be made for occasional use, to be hung before the entrance, in order to prevent other hens from intruding to lay their eggs upon those which sit, a habit to which some are much addicted, and by which a brood is often injured. The common deep square boxes, uncovered at top, are extremely improper, because that form obliges the hen to jump down upon her eggs, whereas for safety she should descend upon them from a very small height, or in a manner walk in upon them. The same objection lies against hampers, with the additional one of the wicker-work admitting the cold in variable weather, during winter or early spring sittings. Many breeders prefer to have all the nests upon the ground, on account of the danger of chickens falling from the nests which are placed above." The ground is preferable for other reasons. The damp arising from the ground assists very materially in incubation. When fowls sit upon wooden floors, or in boxes, the eggs become so dry and parched as to prevent the chicken from disencumbering itself of the shell, and it is liable to perish in its attempts. Hens in a state of nature make their nests upon the ground; and fowls, when left to choose a nest for themselves, generally fix upon a hedge, where the hen conceals herself under the branches of the hedge, and among the grass. In general, the sitting places are too close and confined, and very different in this respect to those that hens select for themselves.
But nests cannot always be allowed to be made on the ground, unless properly secured from vermin, particularly from rats, which will frequently convey away the whole of the eggs from under a hen. And other considerations may render it necessary to have them on a floor, in boxes on the ground, or placed above; in which cases the eggs must be kept properly moistened, for, unless the egg is kept sufficiently damp, its inner membrane becomes so hard and dry that the chicken cannot break through, and perishes. When a hen steals her nest in a hedge or clump of evergreens or bushes, she makes it on the damp ground. She goes in search of food early in the morning, before the dew is off the grass, and returns to her nest with her feathers saturated with moisture. This is the cause of the comparatively successful hatching of the eggs of wild birds. The old farmers' wives did not understand the necessity of damping eggs, but frequently complained of their not hatching, although chickens were found in them, which was, in most cases, entirely caused by want of damping. If, therefore, the weather is warm and wet, all will probably go well; but if the air should be very dry, moisture must be imparted by sprinkling the nest and eggs slightly, when the hen is off feeding, by means of a small brush dipped in tepid water. A small flat brush such as is used by painters is excellent for this purpose, as it does not distribute the water too freely. The ground round about, also, should be watered with hot water, to cause a steam. But the natural moisture of a damp soil is preferable, and never fails.
The nest may be of any shape. A long box divided by partitions into several compartments is much used, but separate boxes or baskets are preferable as being more easily cleaned and freed from vermin. Wooden nest-boxes are preferable to wicker baskets in winter, as the latter let in the cold air, but many prefer wicker baskets in summer for their airiness. A round glazed earthen pan, with shelving sides, like those used in the midland counties for milk, and partially filled with moss, forms a good nest, the moss being easier kept moist in such a pan than in a box. The nest should be made so large that the hen can just fill it, not very deep, and as nearly flat inside at the bottom as possible, so that the eggs may not lean against each other, or they may get broken, especially by the hen turning them.
The best filling for hatching nests is fine dry sand, mould, coal or wood ashes placed on a cut turf, covering it and lining the sides with a little well-broken dry grass, moss, bruised straw, lichen, or liverwort collected from trees, or dry heather, which is the best of all, but cannot always be had. Hay, though soft at first, soon becomes hard and matted, and is also said to breed vermin. Straw is good material, but must be cut into short pieces, for if long straw is used and the hen should catch her foot in it, and drag it after her when she leaves the nest, it will disturb, if not break, the eggs. The nests of the sitting hens in Her Majesty's poultry-yard at Windsor are made of heather, which offers an excellent medium between the natural damp hedge-nest of the hen and the dryness of a box filled with straw, and also enables her to free herself from those insects which are so troublesome to sitting hens. A thick layer of ashes placed under the straw in cold weather will keep in the heat of the hen. A little Scotch snuff is a good thing to keep the nests free from vermin.
Where only a few fowls are kept, and a separate place cannot be found for the sitting hen, she can be placed on a nest which should be covered over with a coop, closed in with a little boarding or some other contrivance for a day or two, to prevent her being disturbed by any other fowls that have been accustomed to lay there. They will then soon use another nest. She should be carefully lifted off her nest, by taking hold of her under the wings, regularly every morning, exercised and fed, and then shut in, so that she cannot be annoyed.
It is best to allow a hen to keep the nest she has chosen when she shows an inclination to sit; and if she continues to sit steadily, and has not a sufficient number of eggs under her, or the eggs you desire her to hatch, remove her gently at night, replace the eggs with the proper batch, and place her quietly upon the nest again. Hens are very fond of choosing their own nests in out of the way places; and where the spot is not unsafe, or too much exposed to the weather, it is best to let her keep possession, for it has been noticed that, when she selects her own nest and manages for herself, she generally brings forth a good and numerous brood. Mr. Tegetmeier observes that he has "reason to believe, indeed, that whatever care may be taken in keeping eggs, their vitality is better preserved when they are allowed to remain in the nest. Perhaps the periodical visits of the hen, while adding to her store of eggs, has a stimulating influence. The warmth communicated in the half-hour during which she occupies the nest may have a tendency to preserve the embryo in a vigorous state."
It is a good plan, before giving an untried hen choice eggs, to let her sit upon a few chalk or stale eggs for a few days, and if she continue to sit with constancy, then to give her the batch for hatching. When choice can be made out of several broody hens for a valuable batch of eggs, one should be selected with rather short legs, a broad body, large wings well furnished with feathers, and having the nails and spurs not too long or sharp. As a rule, hens which are the best layers are the worst sitters, and those with short legs are good sitters, while long-legged hens are not. Dorkings are the best sitters of all breeds, and by high feeding may be induced to sit in October, especially if they have moulted early, and with great care and attention chickens may be reared and made fit for table by Christmas. Early in the spring Dorkings only should be employed as mothers, for they remain much longer with their chickens than the Cochin-Chinas, but the latter may safely be entrusted with a brood after April. Cochins are excellent sitters, and, from the quantity of "fluff" which is peculiar to them, keep the eggs at a high and regular degree of heat. Their short legs also are advantageous for sitting. A Cochin hen can always be easily induced to sit, and eggs of theirs or of Brahma Pootras for sitting, are not wanted in the coldest weather.
Old hens are more steady sitters than pullets, more fond of their brood, and not so apt as pullets to leave them too soon. Indeed, pullets were formerly never allowed to sit before the second year of their laying, but now many eminent authorities think it best to let them sit when they show a strong desire to do so, considering that the prejudice against them upon this point is unfounded, and that young hens sit as well as older fowls. Pullets hatched early will generally begin to lay in November or December, if kept warm and well fed, and will sit in January or February.
Broody hens brought from a distance should be carried in a basket, covered over with a cloth.
The number of eggs to be set under a hen must be according to the extent of her wings and the temperature of the weather. Some say that the number may vary from nine to fourteen, but others would never give more than nine in winter and early spring, and eleven in summer, to the largest hen, and two fewer to the smaller fowls. A Cochin-China may have fifteen of her own in summer. A hen should not be allowed more eggs than she can completely cover; for eggs that are not thoroughly covered become chilled, and fewer and weaker chickens will be hatched from too large a number than from a more moderate allowance. It is not only necessary to consider how many eggs a hen can hatch, but also how many chickens she can cover when they are partly grown. In January and February, not more than seven or eight eggs should be placed under the hen, as she cannot cover more than that number of chickens when they grow large, and exposure to the cold during the long winter nights would destroy many. "The common order to set egges," says Mascall, "is in odde numbers, as seven, nyne, eleven, thirteen, &c., whiche is to make them lye round the neste, and to have the odde egge in the middest."