MECHANICS AND USEFUL ARTS. 75 



Mr. F. O. Ward and Captain Wynants have utilized, and so far per- 

 fected as to make it available for the production of potash on a man- 

 ufacturing si-ale. The felspar is ground to a fine powder, and then 

 mixed with finely-powdered fluorspar. To these chalk and hydrate 

 of lime are added, and the mixture, moistened with water, is made 

 up into balls. These are exposed to a yellowish-red heat for several 

 hours, by which they arc converted into a sort of porous frit. On 

 subsequent lixiviation with hot water this frit yields the whole of the 

 alkali previously existing in the felspar. The alkaline lye of course 

 contains some silica and alumina, but these are easily removed by the 

 addition of a little lime, and then the filtered liquor has only to be 

 boiled down in order to obtain a product very much resembling 

 American potashes. 



Simple as this process appears, it has only been made practically 

 available after an enormous number of experiments, both on a large 

 and small scale. The best proportions of materials, the best temper- 

 ature, and the best mode of applying the heat, had each to be deter- 

 mined, and could only be arrived at after great labor and expense. 

 All these points, however, appear to be settled, and we may now 

 look to the industrial application of the process to furnish us with an 

 abundance of potash. London Chemical Gazette. 



SUMMARY OF INDUSTRIAL NOVELTIES. 



New Plan for Mural Decoration. M. Baize of Paris has recently 

 brought out a new plan of painting in enamel on a large scale, intended 

 to supersede mosaic, fresco, and other methods of mural decoration. 

 The plan seems to be neither more nor less than the method of the Dutch 

 tile-painters of the sixteenth and seventeenth centuries, by means of 

 which they produced pictures, sometimes of considerable size, upon 

 white tiles. The methods seem identical ; thus, white tiles, such as 

 are used on the continent to surround kitchen fireplaces, and the like, 

 are placed upon the floor and numbered, according to their positions, so 

 as to admit of rearrangement. Upon the ground thus displayed, the 

 artist, with a full brush, paints his picture, the tiles are rebated, and 

 the work, where it requires it, retouched. The tiles may then be 

 placed upon a wall, and the work is done. The result is a durable 

 picture, wholly of the artist's own production, on any scale, compara- 

 tively inexpensive, unaffected by a foul atmosphere such as that of 

 London, which may be cleaned with a birch-broom, and be as brilliant 

 in color as we need to have it. Although this plan is by no means a 

 novelty in Art, or even in domestic decoration, it suggests what might 

 well be done in situations where great refinement of ornament is not 

 required. 



Factitious Blocks of Wood. A patent has been taken out by G. 

 Coloinb, of Aigle, Switzerland, for making ornamental blocks of wood 

 as follows : He takes the shavings of soft pine or other wood, and dyes 

 them different colors, then packs them together so as to form a truss, 

 which is put into a frame and dipped into a solution of warm glue ; it 

 is then subjected to severe pressure and formed into a block, after 

 which it is dried with a current of hot air in a warm room. Such blocks 

 of wood may be cut and used for ornamental purposes, as substitutes 

 for high-priced natural woods that are employed for cabinet work. 



