When in full operation, we run twenty-one large machines, and as it requires twenty-seven days to close up each hatch, of course we have a hatch come off nearly every day. Now as each hatch is supposed to occupy two brooder-pens with the corresponding yards, in the course of five or six weeks that brooding-house will be filled with its complement of 3,000 ducklings. These will be of all ages, from the little puff-balls just from the machine, to the half-grown bird of six weeks old. The brooding pipes are supposed to radiate the same amount of heat at the extreme end of the building as they do next the heater, consequently the brooders are of the same temperature in all their parts. Not so the building. As the heater radiates a great deal of heat, the end in which this is located is always 12 or 15 degrees warmer than the other and is thus better adapted to the comfort of the newly hatched ducklings than the other, so I always put the birds fresh from the machine next the heater, while the older ones are passed down the building. This is a very simple process. One end of the partition board is lifted up a little, food scattered in a trough in the empty pen adjoining, the ducklings will rush under in a moment, then the board is dropped. The same process is continued until all are moved and the building filled. [Illustration: INSIDE PLAN OF DOUBLE BROODING HOUSE.] The building just described we term our nursery, and has a capacity of about 2,500 birds. When full, the older birds are probably about two weeks old, and of course these older ones must be removed to make room for successive hatches of younger birds. For this purpose, we constructed a building 125 feet long, 32 feet wide, which we style our double brooding house. It runs east and west with a walk four feet wide through the centre, with brooding-pens on each side. This building has the same capacity of a single building 250 feet long, and accommodates about 5,000 birds. On the south side of this walk our brooder boxes are arranged. At one end of the building is a heater, from which an inch-and-a-half flow and return pipe runs under the brooder boxes the entire length of the building and furnishes heat for the little birds. The brooder-boxes are located twenty inches from the side of the walk. The ducklings are fed and watered in this space, and are not allowed in it except for that purpose. To effect this, the covers of the brooding-boxes, which are six feet long by two feet wide, are cut in the centre the entire length, and hinged with a perpendicular lip, which when closed, meets an upright board below, some two inches high, shutting brooders tight, excluding ducklings from feeding apartment, so that it is always sweet and clean.