CANDLE 683 



agitating tub; where, for every 1,000 Ibs. of the stearic acid, about 2 Ibs. of common 

 black oxide of manganese, and 40 Ibs. of concentrated sulphuric acid, diluted with 

 200 Ibs. of pure water are to be used. This solution ('mixture'), while warm from 

 the heat evolved in diluting the acid, is placed in a suitable vessel above the agitating 

 tub. The stearic acid being at the melting point, in the vessel below, agitation is to 

 be given with a revolving shaft, while the mixed manganese and acid are run slowly 

 down into it, till the whole be well mixed, which generally requires about two hours. 

 The mass is allowed to lie in this state for 48 hours ; after which it may be boiled by 

 steam for 2 or 3 hours, when it will be sufficiently refined. The sulphuric acid, which 

 is at the bottom, is now run off, and the stearic acid which remains is well washed with 

 pure water. It is then put into large conical vessels of stone-ware, inclosed in a box 

 or jacket, kept warm by steam-heat, and lined with conical bags of a suitable strong 

 filtering paper, through which, being warm, it finds its way ; and when the stearic 

 acid has been thus filtered, it is run into blocks, when it will be found to be a beau- 

 tiful stearic acid or palm-wax, and is ready to be made into candles in the usual way. 



The chief solid constituent of palm-oil is margaric acid. This they direct to be 

 melted with tallow, in the proportion of from 10 to 20 Ibs. of the former to 100 Ibs. of 

 the latter. See Newton's Journal, C. 8., xi. 207. 



Messrs. Price and Co. introduced, in 1840, on the occasion of Her Majesty's marriage 

 (when, for the illuminations, a cheap self-snuffing candle was required), a new compo- 

 site candle, which was a mixture of stearic acid and cocoa-nut stearine. Mr. George 

 Gwynne, in 1840, patented a process for purifying the fatty acids by distillation ; this 

 was followed by a similar patent by Dubrunfant ; and Mr. Wilson, of Belmont, Vaux- 

 hall, obtained in August 1842, a patent for improvements in treating fats for making 

 candles. These advances led to many modifications in candle-manufacture. 



If distilled fats are used in making composite candles, they are bleached and 

 hardened in that operation. When palm-oil is the material, it is first saponified, then 

 distilled, granulated by fusion and slow cooling, and cold-pressed; by which 

 means stoaric acid and a light-coloured oil are obtained, which may be mixed with 

 the stearine of cocoa-nut oil, or other stearine. A cheaper article may be had by 

 mixing the entire product of the above distillation with half its weight of distilled 

 and cold-pressed stearic acid of tallow. Tallow is deprived of its oleine by pressure, 

 accompanied by artificial cold if necessary; this being added to the other hard 

 matter, the mixture is converted into fatty acids, and distilled, and the entire product 

 of distillation is employed for making candles ; or it may be pressed to make them 

 harder. As distilled stearic acid is more crystalline than undistilled, 2 or 4 per cent, 

 of wax may be added to assist the combination of the fatty acid with the stearine. 



Candles consisting of alternate layers of tallow and stearine have been made by 

 dipping their wicks alternately in these two fatty bodies in a fluid state. Mr. W. 

 Sykes has gone to the expense of a patent on the contrivance. The wicks are 

 impregnated with a solution of bismuth or borax. 



In a lecture delivered before the Society of Arts by Mr. Wilson, and published in 

 their Journal, he described the progress of the more recent improvements. In this he 

 says: 'Candles, beautiful in appearance, were made by distilling the cocoa-nut 

 acids ; but, on putting them out, they gave off a choking vapour, which produced 

 violent coughing.' This prevented those candles from being brought into the market. 

 ' By distilling cocoa-nut lime-soap, we made beautiful candles, resembling those made 

 from paraffine, burning perfectly ; but the loss of material in the process was so great, 

 that the subsequent improvements superseded its use. Under one part of this patent, 

 the distillation was carried on sometimes with the air partially excluded from the 

 apparatus by means of the vapour of water, sometimes without, the low evaporating 

 point of the cocoa-nut acids rendering the exclusion of air a matter of much less 

 importance than when distilling other fat acids.' At this time, in conjunction with 

 Mr. Jones, Mr. Wilson appears to have first tried using the vapour of water to exclude 

 the air from the apparatus during distillation. This led, in 1842, Messrs. E. Price and 

 Co. to patent, in the names of Wilson and Jones, a process which involved the treatment 

 of fats, previously to distillation, with sulphuric acid, or nitrous gases. M. Fremy, in his 

 valuable paper in the ' Annales de Chimie,' describes treating oils with half their 

 weight of concentrated sulphuric acid, by which their melting point was greatly 

 raised. Ho gave, however, particular directions that the matter under process should 

 be kept cool. Instead of doing this, Mr. Wilson found it advantageous to expose 

 the mixture of fat acid and fat to a high temperature, and this is still done at Price's 

 works. 



1 Our process of sulphuric acid saponification was as follows . Six tons of the 

 material employed usually palm-oil, though occasionally we work cheap animal fat, 

 vegetable oils, and butter, and Japan wax were exposed to the combined action of 

 6| cwts. of concentrated sulphuric acid, at a temperature of 350 F. In this process 



