Chemical Science. 401 



mixed well at a gentle heat, and will yield twelve parts of the 

 preparation. 



When to be used, the linen is to be spread on a table, and the 

 preparation applied by means of a hair brush, and stencil plates of 



ropper*. 



8. NEW APPLICATIONS OF ARTIFICIAL ULTRAMARINE. 



It is well known that a few years since M. Guimet discovered a 

 process of manufacturing ultramarine from its proximate elements, 

 and without the use of lapis lazuli. He has latterly described a 

 great extension of this, his manufacture, in a letter to M. Gay 

 Lussac. A paper manufacturer wished to apply this ultramarine in 

 place of smalt to the coloration of his papers, and was, in conse- 

 quence, supplied with a sufficient quantity to make a large experi- 

 ment. The latter paper made had as good a tint as that coloured 

 with smalt, and was more uniform, but it was found that, in producing 

 this effect, the lib. of ultramarine, because of its extreme division 

 and intense colour, was as effectual as lOlb. of the finest smalts. 

 After this 200lb. of ultramarine were sold to the paper-makers of 

 Lyons at the price of 20 francs per lb., and proved to be more 

 economical than smalt. In consequence, M. Guimet has very much 

 extended his manufactory, and is able to sell ultramarine for these 

 uses at the price of 16 francs per lb. 



The ultramarine for painters requires a particular purification, as 

 well as careful selection from all that is manufactured. The price for 

 the finest quality is 60 francs the lb. The second quality is 20 francs 

 the lb. 



Besides its use in paper-making, the manufacturers of calicoes, 

 muslins, &c., &c., are beginning to use it, and M. Guimet expresses 

 a hope, that shortly France will be entirely independent of other 

 countries for the blues required for these uses *. 



9. REDUCTION OF TITANIUM. (Liebig.) 



Recently prepared chloride of titanium and ammonia (of Rose) is to 

 be introduced into a glass tube, two or three feet long and half an 

 inch in diameter, so as, without being pressed, to occupy the half of 

 It. The tube is to be placed horizontally in a furnace, and attached 

 to an apparatus, by means of which, ammoniacal gas, dried by 

 passing over caustic potassa, may be supplied. The vacant parts of 

 the tube are first to be heated whilst a little ammonia is passed in : 

 gradually the part containing the salt is to be heated and the tempe- 

 rature raised until the tube softens. The chloride is entirely reduced, 

 and the tube being opened, when cold the metal is taken out in the 

 form of a dark blue powder, or in plates, having the lustre of copper. 

 If exposed to the air before it is cold, it will inflame and burn into 

 titanic acid. 



* Jour, de Pharm,, 1831, p. 388. f Arm, de Cbimie, xlvi. 431. 



