To test the condition of a sleeping room, leave it closed in the morning, go into the fresh air for ten or fifteen minutes, return to the room, and if the air seems less pure than the outside air the ventilation is imperfect. _The nose is a sentinel to warn us of danger._ It should be educated to tell the condition of the air we breathe. What a benefit to mankind if some one would invent a gauge to determine the amount of impurities in the air, as heat is tested by a thermometer. Would it not on many occasions give us startling revelations? To aid in improving the air of a house, and especially of a sleeping room, we have a safe, efficient and economical means in the use of unslaked lime and charcoal. A small basket of these should be placed in every invalid’s room, or where children sleep, for the purpose of absorbing the carbonic acid gas of the lungs, and the effluvium of the human body. The discovery of this simple method is attributed to Dr. Bonizzardi, of Italy. He claims, “That people die much more rapidly through the deleterious effects of miasma and carbonic acid gas than by the want of oxygen in the air. To prove his theory, he put three fowls on a perfectly even floor, under three glass cases, and placed in the case containing the first bird nothing but the fowl, in the second one a piece of unslaked lime, while the third contained some pieces of charcoal. In half an hour after the birds were confined he examined them, and found that the bird having neither lime nor charcoal was dead, that the one in the second case containing the unslaked lime was barely alive, while the bird in the case containing charcoal was quite active, and showed no sign of suffering. “The first fowl, having neither lime to absorb the carbonic acid gas of the lungs, nor charcoal to collect on its surface the effluvium of the surrounding air, died of blood poisoning, produced solely by the action of the carbonic acid expelled from the lungs. “The fowl that was supplied with the lime was only quite ill, because the lime had removed one of the causes of death by absorbing the carbonic acid gas; while the bird confined in the case containing the charcoal was only slightly indisposed or ill, because the charcoal absorbed all the exhalations of the lungs and body. “These experiments prove that people die far more quickly from the deleterious action of bodily exhalations than from any deficiency of oxygen in the air. The moral of these experiments is: That a small basket of charcoal should be placed in the room of every invalid, in order that it may absorb the carbonic acid gas floating in the air, and thus render the atmosphere purer and more wholesome.” REST. A daily _siesta_ ought to be taken by the pregnant woman. Even if she feels well and is not accustomed to rest during the day, it would be far better for her to take it regularly. She should plan for it as for any other duty, and will gain by the ability to accomplish more.