458 ANNUAL RECORD OF SCIENCE AND INDUSTRY. 



with water, and afterward mixed with the other ingredients. 

 In a half dry state this mixture may be turned in a lathe like 

 wood, and is chiefly employed in making a kind of pottery 

 ware. When used instead of wood, the mass can be colored 

 with aniline, or other coloring matters. 1 A, December 30, 

 323. 



CEMENT FOR UNITING METALS, ETC. 



A strong cement, which hardens rapidly, may be made, ac- 

 cording to Mr. Bottger, by stirring the finest whitening in a 

 solution of silicate of soda, of 33 Beaume, made so as to form 

 a plastic mass. This can be readily colored to any desired 

 shade. The addition of sifted sulphuret of antimony gives a 

 black cement, which by polishing acquires a metallic lustre ; 

 iron filings render it grayish-black ; zinc dust turns it green, 

 but after polishing it appears like metallic zinc, and may be 

 employed for the permanent repair of zinc ornaments, etc. 

 Carbonate of copper imparts a light green color. Other ad- 

 ditions may be made, as oxide of chrome for dark green, co- 

 balt blue for blue, red lead for orange, vermilion for scarlet, 

 carmine for violet, etc. 12 (7, Ob. Ge.,iv.,S0. 



TUNGSTIC GLUE. 



Tungstic glue bids fair to be an acceptable substitute for 

 hard India-rubber, now so high in price. It is prepared by 

 mixing a thick solution of glue with tungstate of soda and 

 hydrocholoric acid, by means of which a compound of tungstic 

 acid and glue is precipitated, which, at a temperature of 86 

 to 104 Fahrenheit, is sufficiently elastic to admit of being 

 drawn out into very thin sheets. On cooling, this mass be- 

 comes solid and brittle, and on being heated is again soft and 

 plastic. This new compound, it is said, can be used for all the 

 purposes to which hard rubber is adapted. 8 A^February 1, 

 30. 



NEW ENAMEL. 



An excellent enamel, according to Duchemon, is prepared 

 from a mixture of thirty parts, by weight, of saltpetre, ninety 

 parts of silicic acid (fine sands or infusorial earth), and two 

 hundred and fifty parts of litharge. Drawings can be made 

 upon this enamel as upon paper, and the characters can be 



