In the first place, then, mere stuffiness of a room will be often quite sufficient to wake an ordinarily good sleeper, and if continued, to get him into the habit of sleeping badly. If the air in a room gets exhausted of its oxygen, he will during sleep breathe through his mouth as well as his nostrils, the lungs rebelling against their starvation. This continued for several hours will by the consequent dryness of mouth and throat, and the discomfort ensuing upon it, be quite sufficient to wake him, wake him thoroughly, that is to say, with a sense of uneasiness amounting to positive discomfort. A proper bedroom, therefore, should be incapable of stuffiness, that is to say, a window should always be open, and the room be as free as possible from curtains and carpets. No doubt the absence of them (of carpet, anyhow) affects the stuffiness of a room only in a very small degree, but it has its value in this way, that the air is far freer from dust, which is an important point, if for eight hours or so out of every twenty-four you are breathing that air. But it is true that the influx of light in the early morning tends to wake some people, and the absence of curtains lets in light. For this there are two remedies, both equally simple: have blinds of the ordinary dark-blue stuff which quite effectually excludes light, or better, pass a couple of nights, three or four perhaps, in which you are awakened by light. After that you will fail to notice it, and one of the present writers, who for years thought he must awake when light came in, found after doing so once only, that it made not the slightest difference, and he who carefully drew curtains, and had the position of a strange bed altered so as to be away from the light has now often awoke, when called, in a blaze of sunshine. He is, therefore, you will conjecture, a naturally good sleeper. Naturally, no--that is to say, in early life he was a persistently bad one, who used to adopt all kinds of means to go to sleep, of which presently. But for the last six years his record is this: he has, as far as he remembers, through good and ill report, through such anxieties as are inseparable from life itself, through one attack of typhoid fever, and two of influenza, in spite of hard work up till the time of going to bed (in fact, particularly then, since he finds he works best when the small hours begin to grow bigger), lain awake for never more than one complete hour on three occasions. Once he had coincidently a bad cold, on the other two occasions he failed then, and fails now to account for so extraordinary a proceeding. All told, then, in six years he has been awake for three solid hours when he meant to be asleep. Otherwise, he extinguishes his light--and is called.