November i, 1883.] 



THE TROPICAL AGRICULTURIST. 



329 



STEAEINE, GLYCERINE, CANDLES AND 

 SOAP 

 from the oils of the cocouut and African palm 

 were thus noticed by Mr. Leopold Field, in a lecture 

 before the Society of Arts. The Mr. Wilson referred 

 to, is the eminent chemist so long connected with 

 Price's Patent Candle Company, Mr. G. Ferguson 

 Wilson, a brother of the late Mr. David Wilson of 

 Colombo, Ceylon : — 



One of the great obstacles to commercial success in 

 the manufacturing of steariiie was the difficulty of 

 dii-posing of the oil which was a waste product, and 

 would have remained bo, but for the wise step of 

 removing the duty on soap. it is now, however, 

 almost as important as the stearic acid, being em 

 ployed for making what is known as pure oil soap, an 

 article in immense demand among dyers and bleachers. 

 The next process — that of aciditication — requires a 

 short history, by way of preface. Till now, only 

 tallow had been employed for making stearine, though, 

 in 1830, Messrs. Hem pell and Bluudeil took out a 

 patent for making candles from saponified palm oil. 

 These, as you see by the specimen, give a fair light, 

 but are dark iu colour and are greasy to handle, and 

 never became popular. In 1829, Mr. Soames had taken 

 out a patent for pressing coconut oil, obtaining a 

 solid and a liquid. This coconut stearine was a de- 

 cided improvement upon pressed tallow, but the candles 

 made from it still required tnuffing, and eoneequeutly 

 were never extensively used. The composition of 

 coconut oil, as already' shown (Lecture III ), differs 

 very considerably from that of palm oil and tallow ; 

 the proportion of glycerine is comjiaratively small, and 

 the fatty acids very numerous ; some of them, as 

 caproic and caprylic, are volatile at low temperatures 

 and give very jjungent vapours, especially when the 

 candle is blown out, which, of course, tended to 

 render this candle objectionable. It was not till Mr. 

 Wileon brought out his composite candle, which I have 

 already described, composed of the coconut stearine 

 and the new stearic acid, tbat they became popular. 

 Their sale is still very great, though the composi- 

 tion of the present composite caudle difi'ers materially 

 from those first introduced under th.at name. In 1810, 

 Mr. Gv ynne planted a process of distillation in mciio 

 for fatty bodies, and also for distilling fatty acids, 

 under atmospheric pressure. Though the principle was 

 mainly the exclusion of air from the apparatus and 

 was valuable, the working was not found practicable. 

 In 1842, Messrs. Price & Co. — under the name of 

 W. C. J ones— paten tid the process of distillation of 

 iicids from coconut oil alone, and also after combin- 

 ation with lime. Very beautiful candles were iiiaile 

 by this metbod, but were still subject to the same 

 complaint of those of stearine, namely, ;of evolving 

 vapours. The candles made of Ihe product of distil- 

 lation from the coconut lime soap wei'e free from all 

 defects, but their cost was far too great. Various 

 experiments were tried, and patents taken out ; but 

 we cannot stop to consider any till wo reach the 

 patent of Messrs. Wilson audUwynue, in 184.S, which 

 embodied the suj^gestiou of M. Fremy, to heat oils 

 witli acid instead of alkali ; only, inste.ad of follow- 

 ing his recommendation that the vessel should be 

 kept as cuol as possible, the patentees recommended 

 a high temperature, and distillation under superheated 

 steam. I'ho procts-i will be best understood from the 

 actual description. Tallow oil is subjected to the 

 action of strong sulpluiric acid at a very high temper- 

 ature, in the proportion of 6 tons of the oil to 7 cwt. 

 of acid. By this means the glycerine is converted 

 into sulpho-glyccric acid, with evolution of sulphurous 

 acid, and acerlaiu amount of carbon. After the acid 

 trcatincutj the black mass in the vessel looks any- 



thing but promising. A little washing, however, 

 frees it from the residual charcoal and aeid, and it 

 is then transferred into a still, into which super- 

 heated steam plays, and this, with the aid of gentle 

 "bottom heat," distils over the acid. Here is the 

 raw palm oil of a golden-yellow colour. Here the 

 black mass produced by the acid treatment, and 

 this firm white substance the product of distillation. 

 In the still a black thick pitch remains, known com. 

 mercially as palm pitch. What has come over is 

 pure palintio acid. The medium runnings of the 

 distillate are the best. The first and last are not so 

 good, and are used for inferior candles. From this 

 palmlic acid the finest compoeite candles are now 

 made. Price & Co. subject their distillate to hot 

 pressure, and obtain the " Belmont Sperm " thereby. 

 You will remark the beauty of their appearance, and 

 thii clear lustre of the tlame. I have here burning, 

 side by side, a candle of tallow, and a candle of 

 stearic acid, with equal wicks, and you will perceive 

 at once the difference made by the e.xclusion of the 

 glycerine. I have forgotten to mention, in the de- 

 scription of the palm oil the kernel of the nut, from 

 which is obtained a very large amount of oil, equal 

 to, if not exceeding, the quantity produced from the 

 fruit. The composition, however, is quite different, 

 being, in fact, almost identical with tfiat of coconut 

 oil, which it replaces in any instances, especially in 

 the manufacture of soap, for which both these oils 

 are abundantly employed. So much for the saponific- 

 ation and distillation process. Mr. Tilghmaun, in 

 1854, took out a patent for the separation of fats 

 into acids and glycerine by heating with water under 

 pressure. He suggested pumping the mixture of fat 

 and water through a coil heated to a temperature 

 exceeding 600° Fahr., and at a pressure of 'J, 000 lb. 

 to the inch. Messrs. Wilson and Payne patented a 

 method by which superheated steam passed into the 

 fat at ordinary pressure efl'eoted the sepuration, and 

 distilled both acids aud glycerine. By resubjtc- 

 ting the latter to this process, Mr. Wilson 

 obtained the beautiful glycerine for which Price's 

 Patent Candle Co. have so high aud just a reput- 

 ation. I cannot dilate as I shonld like to upon the 

 uses and beauties of this beautiful idcohol. They 

 form part of that brauoh of chemistry known as 

 sapouilicalion, a wide reaching aud deeiily interesting 

 subject. However, Mr. Tilghmann's idia has been 

 amplified, aud on the Coutinent a great part of tho 

 stearine is made by what is called the .autoelive pro- 

 cess. The tallow aud palm oil are introduced into a 

 stout copper vessel provided with astirrer, into which 

 superheated steam is passed tdi the pressure reaches 

 250 lb. oa the inch. After several hours' agitaiinn at 

 this pressure, i he separation is complete. Each of these 

 methods has its particular advantages, and is applied 

 to certain specialities of stearine, in the choice of 

 which experience is the only guide. 1 have on the 

 table samples of caudles produced by all the methods 

 I have named, and many more (which will be parti- 

 culaiized in the last lecture on candles). I cannot 

 conclude without diawing your attention to tlio great 

 results which have followed the discoveries of Chevreul 

 and Wilson. Had it not been shown thai by these 

 processes the worst and darkest greases can bo forced 

 to yield a clean and beautiful substance, palm oil would 

 have been almost useless to the candle- maker. As it 

 is, over 40,000 tons are imported annually into Eng- 

 land, aud no d"Ubt, far more into the (!untiueut and 

 America. The kings of the countries where the palm 

 tree grows find tiiat the labour of their subjects, in 

 collecting the fruit and extracting the oil, is far more 

 remuuerative to them than the selling of these sub- 

 jects into slavery. Being as keenly alive to i heir own 

 interests as any white men can be, they have become 

 humauo as a matter of business. By encouraging the 



