L. MECHANICS AND ENGINEERING. 479 



that a considerably increased amount of iron has been the 

 consequence of the elevation in height of the furnaces, and 

 that in districts where tender cokes were used, a height of 

 sixty feet might be safely obtained, but perhaps not exceed- 

 ed. 16 A, January, 1872, 100. 



PREPARATION OF FUEL FROM FIXE COAL. 



Mr. E. Loiseau, of Philadelphia, lately submitted to the 

 Franklin Institute specimens to illustrate his proposed new 

 method of utilizing coal-dust. This consists in thoroughly 

 mixing about seven per cent, of clay with the fine coal, and 

 forming the mass into balls, and then dipping these into a 

 bath of benzine containing some resin in solution the object 

 of this operation being to render them impervious to moist- 

 ure. The solution penetrates the lumps to the extent of about 

 one fourth of an inch, and, after the evaporation of the ben- 

 zine, which takes place rapidly upon exposure to a current of 

 air, a film of resin is left behind, which so effectually stops up 

 all crevices that, in the experiments made by the Franklin 

 Institute Committee on Science and Arts, while investigating 

 the process, masses which had lain in water for twelve hours 

 were found to have lost none of their compactness, and to 

 be still dry in the interior. The consumption of the artificial 

 fuel took place very satisfactorily, all the specimens burning 

 till completely ashed. 



The committee found that the heating power of the mate- 

 rial was somewhat below the average of solid coal, but that 

 the compactness of the substance will probably allow its 

 transportation with as little loss from breakage as is suffered 

 by many kinds of coal now brought to market. The conclu- 

 sion arrived at was that the plan is one of the most practicable 

 yet submitted to the public for utilizing this waste product, 

 the slight cost of its production being one great point in its 

 favor. 1 Z>, January, 1872, 5. 



dank's puddling furnace. 



Iron manufacturers in Great Britain arc conQratulatins: 

 themselves upon the introduction into Great Britain of the 

 invention of Mr. Dank, of Cincinnati, by which machine pud- 

 dling has become practicable. Heretofore the operation of 

 puddling, or the conversion of ores or cast iron into wrought 



