Page:Cyclopedia of Painting-Armstrong, George D (1908).djvu/428

420 other source enters the perforations in the plate, and, passing through the chambers, causes the agitators to lift the powder and agitate it, and at the same time the air pressure forces the powder through the perforations in the cap in fine streams of dust, and of course by moving the distributor, the dust may be distributed upon the floating oil or varnish as may be desired. It is obvious that the design of the marble, stone, or other article is produced upon the floating body of oil and varnish before it is applied to the glass, and it is also obvious that by coating the surface of the glass with varnish or other adhesive material of a like nature, upon placing the same with the surface having the varnish or adhesive material down, so that it shall be brought in contact with the coloring matter held by the floating surface or layer of oil and varnish, the coloring matter will immediately adhere to the japan or other adhesive coating, and will thereby become fastened to the glass, so that upon the removal of the glass the design laid out upon the floating layer of japan and oil is removed from the water, together with such of the floating oil and japan as unites therewith. Of course the coloring or mottled or other appearance of any marble or other stone, or of any other material, may be reproduced upon the glass by this process, as it will only be necessary to change the dry colors to correspond to those of the stone or article to be imitated or copied.

Metallizing Wood. A new method of treating wood, which gives it the appearance of a piece of shining polished metal, with a surface so hard and smooth as to be susceptible of a high polish, is as follows: The wood is first steeped in a bath of caustic alkali for two or three days, according to its degree of permeability, at a temperature of between 165° and 197° Fahrenheit. It is then placed in a second bath of hydrosulphate of calcium, to which a concentrated solution of sulphur is added after some twenty-four to thirty-six hours. The third bath is one of acetate