PROCEEDINGS OF THE POLYTECHNIC ASSOCIATION. 3G5 



of tlio Minin^i^ Engineer, Mr. Charles Aubel, at the Iron and Copper Smelt- 

 ing- Works of Prince Dcniidoft', in Nishnc Tagiisk, at the foot of the Ural 

 Mtiuntains. After three years of suecessful practice, the same engineer 

 introduced the furnace into Germany, where it has been liighly approved. 

 It Ins been patented in this country, as well as in the prominent kingdoms 

 of Europe. It is called tlie "universal" furnace because with but slight 

 nitHlilications it can be succ(\^.sfully used in smelting iron, copper, nickel, 

 tin, lead, silver, gold, and other ores. Also, for the direct production of 

 caststeel, and the liquefaction of metals in general. 



The tranverse section of this furnace is a parallelogram. The hearth is 

 usually three feet by eighteen in extent, and the width of the chamber 

 gradually increases to the top, where it is seven feet. The height is about 

 thirty feet. There arc twelve tuyeres, six on each side, alternating at 

 regular intervals of about two feet. It is claimed that this arrangement 

 gives a more perfect melting zone tlian is found in the ordinary furnace, 

 and that there is a great saving of fuel and time in the reduction of ores, as 

 well as expense, in erecting such a furnace. 



Dr. D. D. Parmelee thought the material saved in not building the furnace 

 so high as those now used, would not make np for the increased amount 

 required to give the same capacity as the circular furnace, because of all 

 figures of the same dimensions the circle includes the greatest area. 



The Chairman remarked it would require more power to drive the same 

 quantity of air through twelve tuyeres than through four, as is usually 

 done; still this increase of power to produce the blast need not be taken 

 into serious consideration if there is a saving of time and coal in the 

 reduction of the ore. He hoped there would be soon such a practical 

 application of the method in this country as would test its efficiency and 

 economy. 



New Gold Separatee. 



5Ir. Floury also presented illustrations of Dr. A. W. Hall's qnartz-crusli- 

 ing and amalgamating machinery. After reducing the ore to an impalpa- 

 ble povvder it is united in the trough with the (|nicksilver, but to complete 

 the work, by gathering the invisible golden scales that accurately float in 

 the water, the liquid is drawn out of the trough by means of a syphon, the 

 bottom of which is bent upwards and contains mercury ; the pressure on 

 the column of water in the syphon causes it to pass through the mercury, 

 which, it is claimed, will arrest the remaining particles of gold. Mr. 

 Fleury illustrated, with a glass syphon, water, and mercury, this part of 

 the apparatus. 



In discussing its efficacy, the Chairman said there must be considerable 

 dittereiice between the height of the bottom of the trough and the place of 

 final discharge to make it eifectivo; and were it reciuisite to again lift the 

 water, to discharge it from the building, it would be more economical to 

 force the gold-bearing water, in fine jets, through the mercury, by other 

 means than the syphon. 



Mr. Clinton Rosovelt, Mr. Fleury, and others, offered suggestions touch- 

 ing the cause which allows water to suspend in it a metal having nineteen 

 times its specific graviiy. 



