You keep bees. Here is a hive, I see, crowded with the busy insects. By the numbers that I observe clustering about the low arched door, and bustling out and in so incessantly, I learn that the industrious little fellows must be very closely packed together in their straw house. There must be many thousands of them dwelling together in a place that can not, at the most, equal more than a couple of square feet; and there is not a single window in the straw wall; no opening of any kind but the low, and half-choked entrance. Really, if those bees need to breathe, you who have furnished them with their dwelling must be nearly as bad as the cruel nabob, who shut up his prisoners in the Indian Black Hole! Those bees certainly do need to breathe every bit as much as men and women; and what is more, they manage to breathe ten times better than you do at night. Notwithstanding all the crowding there is within their close dwelling, the air never gets there into the poisonous state in which the air of your sleeping room is by the morning. The bees take care that it shall not do so. Just bend down your ear and listen near the hive for a minute. Do you hear that incessant low humming? That is the bees hard at work, making an artificial wind. It is the sound of a couple of score of broad, stiff fans, flapping to and fro with great rapidity. Look, I drop this piece of light thistle-down near the door of the hive, and you see it is at once blown away from it by a steady draught. If you could see through the straw walls, you would notice twenty little sturdy fellows holding on to the floor of the hive with their feet, just within the door, and flapping their wings backwards and forwards without a moment’s pause. Now and then one or two tired insects drop out from the line of the fanners, but their places are immediately filled by fresh recruits, who lay hold of the floor and fall vigorously to work with their wings. This is the appointed band of air-purifiers, plying their business for the good of the entire community, and wafting a fresh breeze continuously through the hive. The bees take it by turns to carry on this necessary labor, and some of them are always at it. The humming caused by the rapid vibrations of their fans, scarcely ever ceases. It has been ascertained that air taken from the inside of a hive, is quite as pure as the fresh air that floats in the open space around; so perfectly do these little earnest workmen perform their purifying task.