The Nuremberg metallic dust is said to have been the invention of an artist of that city, named John Hautsch, born in 1595, died in 1670; his descendants have continued its preparation to the present time. It is produced from filings of metals of several descriptions washed well in a strong lixivious water, then being placed upon a sheet of copper, are put upon a strong fire, and continually stirred till the colour is altered. Those of tin, by this process, acquire every shade of gold colour, with its metallic lustre; those of copper, different shades of flame colour; those of iron or steel, a blue or violet; of tin and bismuth mixed, a white or bluish white colour. The dust tinged in this manner is then put through a flatting-mill, consisting of two rollers of the hardest steel, like those used by gold and silver wire-drawers; for the greater convenience a funnel is placed over them. French covered paper manufactured from this material is called _papiers avec paillettes_. Its lustre is so durable that it is said to continue unaltered for many years even on the walls of sitting apartments. This metallic dust is an article of commerce, being exported from Germany. As early as the seventeenth century, the miners of Silesia collected and sold, for various purposes, a material they call _glimmer_, being bright, shining particles of various metals, which those mines produce in great profusion; even the black, we are told, acquires a gold colour by being exposed to a strong heat. This was manufactured by the holy sisters of Reichenstein, into a variety of ornaments; with it they decorated their images, strewing over them a shining kind of _talc_. The silver coloured glimmer had not, however, so great a brilliancy or variety as the Nuremberg metallic dust; for which purposes that article has a decided superiority. For the various purposes to which these ornaments are to be applied, different adhesive substances should be used; in some cases glue would have the effect, to be first drawn over the substance; in others, a strong varnish, in which wax is dissolved; and for others, various kinds of gums. Those substances being so covered, the dust may be put in a common pepper-castor, and applied by sifting it over the substance to be so covered. Different figures may be drawn with a pencil, and the box of dust shook over them, as far as the extent of the lines covered with glue; the dust will only fasten so far as it meets with what produces adhesion. PAINTING.