1865.] Alining, Mineralogy, and Metallurgy. 123 



These blocks are placed ou a furnace with an inclined hearth, and 

 subjected to a low degree of heat, sufficient to cause the lead to melt 

 and run off, but not to melt the zinc, silver, and gold. 



A discovery, which promises to be an important one, has been 

 made by M. Basset, of Paris, in the process of reducing the chlorides 

 of aluminium. It is that the metalloids and metals which, by double 

 decomposition, will form more fusible and more volatile compounds than 

 the chloride of aluminium, may be employed in reducing the latter. 

 Zinc is used in preference to any other metal. When the chloride of 

 aluminium is brought into contact with zinc, at a temperature of 

 from 250° to 300° centigrade, a chloride of zinc and free aluminium 

 is formed. This latter will dissolve in an excess of zinc, and the 

 chloride of zinc combining with the chloride of sodium, the mass be- 

 comes thick or pasty, and eventually solid, while the alloy of zinc and 

 aluminium remains fluid. If the temperature of the mass is raised 

 it again liquifies, and the zinc reduces another portion of the chlo- 

 ride, and the excess of zinc becomes enriched with an additional 

 quantity of aluminium The rich alloy is then melted with the 

 addition of more chloride of aluminium, and kept well stirred until 

 very nearly pure aluminium is obtained. The small quantity of zinc 

 remaining is volatilized at nearly a white heat, and pure aluminium 

 is obtained. If this process answers upon a more extensive trial, 

 aluminium will be produced at a much cheaper rate than hitherto, 

 the great cost in its manufacture at present being due to the sodium 

 employed. 



Amongst the curiosities of modern metallurgy, we must regard 

 some of the enormous castings which are made by our iron manufac- 

 turers. At the end of October, Messrs. J. M. Stanley and Co. cast 

 two anvil blocks, each weighing 160 tons. The mould was twelve 

 feet square at the base, and eleven feet six inches deep. This was 

 dug out in the centre of the workshop, and from five furnaces con- 

 structed around the building the molten iron was run. The first 

 furnace was tapped at six o'clock in the morning, and twelve hours 

 were necessary to fill the mould. This enormous mass of iron took 

 six weeks to cool, and it was then, by means of hydraulic power, 

 lifted from the mould. 



These anvils are intended for the gun-manufactory of Messrs. Firth 

 and Sons, and each anvil is prepared to receive the blows of a twenty- 

 five ton Nasmyth hammer. 



Mr. Griffith's puddling machine, which we noticed in a former 

 number, promises to produce a revolution in the puddling system. It 

 is being adopted in several iron works. An experienced correspon- 

 dent writes : — " The puddlers are treating the ' Iron man ' as a friend 

 and helper. It is not to be expected that this machine, or any other, 

 will supersede entirely human skill and exertions. The judgment, 

 attention, and practical skill of the puddler, will always be required ; 

 but this apparatus will lessen very much the physical toil now endured, 

 and it more than pays for its application in the increased quantity and 

 better quality of the work accomplished." 



