MECHANICS AXI) USEFUL ARTS. 127 



obvinu<ly affords us the means of multiplying, at very little cost, accurate 

 copies of rare and costly woods, marquetrie, mosaic, and inlaid work 

 generally, the which may be vised for paper hangings, as wainscoting and 

 panelling ; or, if well varnished, with hard varnish, serve for many 

 descriptions of "occasional furniture," toys, and boxes of various kinds, 

 for which purpose choice veneers are now employed ; thus furnishing 

 a great variety of cheap and tasteful things at a cost within the reach of 

 people of limited means. 



M. Abate also describes another process he call? metallography t or print- 

 ing on metallic surfaces from engraved wood blocks. In. this process the 

 block is damped with a solution of such salts as are decomposed by 

 contact with certain salts ; as, for instance, the salts of copper, antimony, 

 &c., applied to the block and printed on zinc and tin ; or of hydro- 

 sulphuret of ammonia, on copper, brass and silver ; salts which deposit 

 either an adherent metallic pellicle, a film of colored metallic oxide, or 

 stain the metal by the formation of a sulphuret ; thus producii)g the figure 

 cut on the block as in ordinary printing. 



Galvano-plastie Niello. Xielio, a peculiar style of enamelling, consists 

 in engraving or stamping figures on a plate of silver or gold, and then 

 filling the incised lines, or impressed pattern, with a sort of enamel, 

 differing, however, from true enamel, which is a kind of glass, by being 

 formed of a mixture of the sulphurets of lead, silver and copper. This 

 mixture is of a black color hence the name niello, from nigellum, derived 

 from, niger, black and when melted into the intaglio parts of a plate, 

 gives it somewhat the appearance of an inked engraved copper plate. A 

 new kind of niello work has lately been introduced on the Continent, in 

 which, however, the figures are not produced by an enamel of sulphuret 

 of silver, as in the true niello, but by a different colored metal : tints on a 

 plate of gold may be produced fine engravings, the lines of which are in 

 silver, and so on. * * * Many highly ornamental and useful appli- 

 cations might be made of these processes, especially in the manufac- 

 ture of church furniture. Instead of simply engraving the r.ame and 

 legend upon pieces of plate presented to persons, it might be put in letters 

 of gold at very little more expense. Jlining Journal, 



GREAT ORGAN AT LIVERPOOL. 



The following particulars of interest are published concerning the 

 monster organ recently placed in the Town Hall of Liverpool, by Mr. 

 Willis : 



The instrument consists of four rows of keys, from G to A, i. e._ GG to 

 A in aitissimo, C3 notes ; and two octaves and a half of pedals, from C to 

 F, i. e. CCC to F, 30 notes. There are 108 stops and 8,000 pipes, varying 

 in length from 32 feet to three- eighths of an inch, ten octaves apart. The 

 grand source of wind is from two immense bellows, each having three 

 feeders, placed in the vaults below the floor of the hall. These are blown 



