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carefully done, it is surprising how soon this process will pro-duce a glowing fire. Ashes and small cinders mixed with water into a mass, and put on the back of a fire with a few coals, burn well, so that ashes may thus be entirely burnt up. In stoves under boilers, this mixture is very useful, as it lasts long, with little addition.
SMOKY CHIMNEYS.
The cause of smokiness in chimneys are various; but all .re connected with the properties of air and heat, for the smoke is only particles of culm ascending through the agency of heated air. To make a chimney vent well, the column of heated air from the fire must not be entangled with cold air from beneath nor retarded by cold air coming down the chimney. To effect these objects, the fire-place must not be much larger than the grate, and the chimney must be of a certain length and bent. The great leading cause of smoki-ness is cold air somehow or other mixing with the warm air about the mouth or throat of the chinmey, and so causing a sluggishness in the ascent, or no ascent at all. Therefore, the nearer the air is made to pass the fire on all sides, the more rarefied it will be; and the less vacancy there is in the chim-ney-place, it will ascend with the greater rapidity. A proper contraction of the mouth of the chimney, at the same time allowing the fire to be fed freely with air, will be found in most instauees to cure smoke. Of late, certain contrivances called dampers, by which the chimney throat can be narrowed,have been the means of effecting draughts, and so curing smoke. It should be noted, that in contracting chimney-throats, the contraction should not be all at once, but at first gradual, and then straight upward, so as not to allow a volume of cold air to lurk in a hollow above. A chimney being wide at bottom, and gradually narrowing towards the next storey, allows the coldish air to hang about the lower parts, by which, when a gust of wind comes, the smoke is driven back into the room. This kind of smokiness is the most teasing of all the forms of chimney diseases. Every little puff of wind sends a smaller or larger quantity of smoke into the apartment, and often when it is least expected. Perhaps this kind of smoki-ness is not in all cases caused by wrong construction, but arises from the situation of the house; and of this we shall imme-diately say a few words. If a funnel of a chimney be made too narrow to afford an easy passage to the top, the smoke will then naturally be forced into the room to find some otber passage; this defect
