3. Feather beds--if used in the nursery--will inevitably discharge more or less of dust and down; both of which are injurious to the tender lungs of the infant. Mattresses are better for persons of every age, than soft feather beds. They may be made of horse hair or moss; but hair is the best. If the mattress does not appear to be warm enough for the very young infant, a blanket may be spread over it. Dr. Dewees says that in case mattresses cannot be had, "the sacking bottom" may be substituted, or "even the floor;" at least in warm weather: "for almost anything," he adds, "is preferable to feathers." Macnish, in his "Philosophy of Sleep," objects strongly to air beds, and says that he can assert "from experience," that they are the very worst that can possibly be employed. My theories--for I have had no experience on the subject--would lead me to a similar conclusion. A British writer of eminence assures us that the higher classes in Ireland, to a considerable extent, accustom themselves and their infants to sleep on bags of cut straw, overspread with blankets and a light coverlid; and that the custom is rapidly finding favor. I have slept on straw, both in winter and summer, for many years, yet I am always warm; and those who know my habits say I use less _covering_ on my bed than almost any individual whom they have ever known. I have no hostility to soft beds, especially for young children and feeble adults, could softness be secured without much heat and relaxation of the system. On the contrary, it is certainly desirable, in itself, to have the bed so soft that as large a proportion of the surface of the body may rest on it as possible. But I consider hardness as a much smaller evil than feathers. It is worthy of remark how generally physicians, for the last hundred years, have recommended hard beds, especially straw beds or hair mattresses, to their more feeble and delicate patients. This fact might at least quiet our apprehensions in regard to their tendency on those who are accustomed to them in early infancy. Some writers on these subjects appear to doubt whether, after all that they say, they shall have much influence on mothers in inducing them to give up feather beds for their infants. But they need not be so faithless. Multitudes have already been reformed by their writings; and multitudes larger still would be so, could they gain access to them. It is a most serious evil that they are often so written and published that comparatively few mothers will ever possess them. The pillow, as well as the bed, should be rather hard; and its thickness should be much less than is usual, or we shall do mischief by bending the neck, and thus compressing the vessels, and obstructing the circulation of the blood. But on this subject I will say more, when I come to treat on "Posture."