I wrote him at once that for every fifteen chicks he had taken out he had taken one degree of heat from his machine, and had he followed instructions he would not have suffered loss. He wrote back that he had shut up his machine for the season, but that he should run it one more hatch just to prove that I was wrong. At the end of three weeks a letter was received saying, "I tender you my hat. I got a splendid hatch of 88-1/2 per cent." Proving that occasionally there is danger of the operator knowing too much. After the ducklings are all out, the egg-trays should be removed, the valves opened, and the machine cooled down to 90 degrees, and the birds allowed to remain in the machine for at least twenty-four hours. I always cover the bottom of machine with an inch of fine wheat-bran, otherwise the ducklings would soon make it filthy and offensive. This acts both as absorbent and disinfectant. After each hatch there will be more or less fertile eggs left in the trays with dead ducklings in them. There will be, comparatively, but few of these in the spring of the year, but during the latter part of the summer there will be more of them, and many of the eggs will have but little vitality in them. Forcing the Bird Reduces the Vitality of the Egg. The reason is this: the bird in its natural condition does not produce her eggs in our climate until April. She will lay twenty-five to thirty eggs, then show a desire to incubate, then will recuperate, and set a second time, perhaps giving a total of thirty-five or forty eggs. Now, we have completely reversed nature in this respect. By judicious feeding, good care, warm quarters, and careful breeding, we have induced the bird to produce her eggs in winter instead of summer, and, not only that, we compel her to lay three or four times as many of them; and when the poor bird shows a desire to incubate and recuperate her exhausted frame, we induce a change of mind, as soon as possible, and set her at it again. As a natural consequence, as the warm season advances many of the birds are off duty, as it were, and the eggs not only decrease in numbers but in size as well, and during the extreme heat of summer, the later part of July and August especially, the eggs show a decided want of vitality. I never expect, at this season, to realize more than one duckling from two eggs. The same machine full of eggs that would give a hatch of 350 ducklings in the early spring, at this season will not give more than 175 to 200. The eggs appear to be as well fertilized during the first two or three days as in the early spring but evidently there is not vitality enough to carry them through, as the germs soon begin to die, and before the hatch is out you have taken nearly one-half of the eggs away as worthless. Nor is this all.