“When a strong light, for the purposes of reading or writing, be required, a white silk or paper may be used, as is common, over the skeleton; but when it be required that the light should be dispersed over the room, a glass of a similar shape may be adopted, for the purpose of preventing the flame from being influenced by any agitation of the air of the room. If the upper circle of the shade be four inches in diameter, the apex of the flame will be within it during more than half the time of the complete consumption of the candle; the shade will not, therefore, require adjusting for the purpose of preventing injury to the silk, or whatever else may be used over the skeleton, more than once during that time.
“Being myself much averse to the interruptions which a candle used in a vertical position occasions, and which, though short, may, under some circumstances, be highly vexatious, I wish to extend to others a benefit which I prize rather highly.”
Lord STANHOPE[9] has published a simple method of manufacturing candles, which, according to his Lordship’s statement, is superior to the method usually employed. The principles upon which the process depends are the following:--First, the wick of the candle is to have only three-fourths of the usual number of cotton threads, if the candle be of wax or spermaceti; and only two-thirds of the usual number, if the candle be of tallow. Secondly, it is required that the wick in all cases be perfectly free from moisture, a circumstance seldom attended to in the manufacturing of candles; and thirdly, to deprive the wick of wax candles, of all the air which is entangled in its fibres, and this may conveniently be done, by boiling it in melted wax, till no more air bubbles, or froth appear on the surface of the fluid.
If these circumstances be attended to, three candles of any size thus prepared, last as long as four of the same size manufactured in the common way. The light which they afford is superior and more steady than the light of common candles; and lastly, candles made in this manner, whether of wax, spermaceti, or tallow, do not require to be snuffed as often. Besides all this, they flame much less, and are consequently better for writing, reading, working and drawing, than candles made by the common method.