Sperm-oil, lard, tallow, etc., have been superseded to such an extent by kerosene that it is scarcely worth while to give any special directions in regard to them. In the choice of kerosene, attention should be paid to two points: its _safety_, and its _light-giving qualities_. Kerosene is not a simple fluid, like water; but is a mixture of several liquids, all of which boil at different temperatures. Good kerosene-oil should be purified from all that portion which boils or evaporates at a low temperature; for it is the production of this vapor, and its mixture with atmospheric air, that gives rise to those terrible explosions which sometimes occur when a light is brought near a can of poor oil. To test the oil in this respect, pour a little into an iron spoon, and heat it over a lamp until it is moderately warm to the touch. If the oil produces vapor which can be set on fire by means of a flame held a short distance above the surface of the liquid, it is bad. Good oil poured into a tea-cup or on the floor does not easily take fire when a light is brought in contact with it. Poor oil will instantly ignite under the same circumstances, and hence the breaking of a lamp filled with poor oil is always attended by great peril of a conflagration. Not only the safety but also the light-giving qualities of kerosene are greatly enhanced by the removal of these volatile and dangerous oils. Hence, while good kerosene should be clear in color, and free from all matters which can gum up the wick and thus interfere with free circulation and combustion, it should also be perfectly safe. It ought to be kept in a cool, dark place, and carefully excluded from the air. The care of lamps requires so much attention and discretion, that many ladies choose to do this work themselves, rather than trust it with domestics. To do it properly, provide the following things: an old waiter to hold all the articles used; a lamp-filler, with a spout, small at the end, and turned up to prevent oil from dripping; proper wicks, and a basket or box to hold them; a lamp-trimmer made for the purpose, or a pair of _sharp_ scissors; a small soap-cup and soap; some washing soda in a broad-mouthed bottle; and several soft cloths to wash the articles and towels to wipe them. If every thing, after being used, is cleansed from oil and then kept neatly, it will not be so unpleasant a task as it usually is to take care of lamps.