In the large rearing houses there is a special chamber for the incubation. Various simple, convenient, cheap apparatuses, whose main object is to create a permanent warm and damp atmosphere, whose degree of heat can be regulated at will, have been proposed. M. Louis Leclerc, in his pamphlet entitled "Petite Magnanerie," has given a description and drawing of a little box which is very useful for facilitating the hatching of eggs. We refer those of our readers who wish for further information on the subject to that work. As soon as the worms are hatched, the eggs are covered with net, and over this are placed mulberry boughs, covered with tender leaves, on which all the little worms congregate. They are then lifted up with a hook made of thin wire, and the worms are placed on a table covered with paper, leaving a proper space between each. They are given, as their first meal, tender leaves cut into little pieces with a knife. These are the operations gone through for the two raisings of worms on the second and third day of the hatching. During this first age they give them from six to eight meals a day, taking care to distribute their food to them as equally as possible. The first meal is given at five o'clock in the morning; the last at eleven or twelve o'clock at night. When the moult is approaching, the young ones are made to climb on to boughs having tender leaves, so that they can be moved to litters as thin and clean as possible, and there sleep in a good state of health. When the mass of worms is well awake again, the next thing to do is to take them off the litter on which they moulted, and to give them food. If this problem were proposed to a person strange to the operation which is now occupying our attention--to separate the worms from the faded and withered food upon which they are reposing, without touching them--he would certainly be very much at a loss what to answer. The solution of this problem presented for a long time great difficulties, and occasioned numerous reverses in the rearing. Now-a-days, thanks to the employment of a net, the _délitement_, or taking them off their bed, has become an easy operation. Over the worms, placed on a table, is spread a net, the meshes of which are broad enough to allow them to pass through. On this net are spread the leaves which are to compose a meal. The worms immediately leave the old food, and get on to the new leaves. They then lift the litter with the worms, and throw away the old leaves, now unoccupied, clean the table, and replace the net with the worms. At the next _délitement_ the first net is found under the litter. Figs. 211 and 212 represent two forms of these nets made of thread.