FUELS AND THEIR UTILIZATION. 41 



facture from lignites. The labor of the most prominent chemists and manu- 

 facturers was long directed to the development of the process of its manufac- 

 ture; and although it has lost in importance since the utilization of the large 

 deposits of ozocerite for this purpose, and since kerosene oil has so extensively 

 taken the place of candles, a number of factories are still profitably engaged 

 in its manufacture. 



Parafime was discovered in 1830, by Reichenbach, who at once recom- 

 mended it for the manufacture of candles, because it burned without soot. 

 Notwithstanding its valuable qualities for this purpose were fully recognized 

 at this early day, the cost of its manufacture limited its common use until in 

 1850 James Young erected a factory at Manchester, manufacturing the paraf- 

 fine from coals and lignites. Ever since this time it has kept a prominent 

 place in the industry of candles, and its manufacture has been highly devel- 

 oped. 



One of the oldest methods of manufacturing parafifine from lignite will be 

 mentioned here, as the principle of the process has not changed, though the 

 details have been altered and improved. This process consisted of the fol- 

 lowing various manipulations: The lignite is broken into fragments of the 

 average size of a walnut, and if it contain sulphur it is moistened with lime- 

 water. The coal so prepared, is transported to the drying oven, which is 

 generally two hundred feet long by twenty feet wide, and so constructed that 

 the hot ash remaining after the distillation in the retorts can be used for the 

 dessication of the lignites. After the coal has been thoroughly dried it is 

 subjected to distillation, one firing being sufficient for the heating of two re- 

 torts. The firegas is conducted below them into a chimney of considerable 

 draft, usually forty feet high. A large reservoir receives the liquid products 

 of distillation and serves to separate the ammonia from the tar. The ash is 

 treated with the ammonia and furnishes an excellent fertilizer largely in de- 

 mand. To remove the hydrosulphuric acid and ammonia still contained in 

 the tar, it is well mixed in a large revolving drum with a solution of copperas 

 and then subjected to distillation with superheated steam. The vapors, as 

 distilled, are condensed in cooling spirals and separated into mineral oils 

 (photogene and solar oil), lubricating oils, and parafifine. The paraffine is 

 obtained from the remaining liquid through crystallization, and the raw pro- 

 duct purified through repeated pressing and washing with sulphuric acid and 

 liquor of potash. The construction of the oven can be such and the process 

 can be so conducted that but little coke is produced, and principally ash, tar, 

 ammonia, water, and volatile matter be produced from the distillation of the 

 lignite. 



As mentioned before, the process has been greatly improved in all its 

 phases, but only a few of the most important changes need be noticed. In 



