CHEMISTRY. 437 



cblormes of iodiue are the trichloride, and tw^o modifications, a and 

 /i of the uionochloride. The oe compound crystallizes in long, red nee- 

 dles, melting at 27". 2, while the (i modification forms brownish red 

 lamella?, which fuse at 13'^.9. All these bodies can exist below their 

 points of fusion in liquid mixtures containing an excess of either ele- 

 ment, and varying in composition with temperature. In the gaseous 

 state only the molecule ICl. is possible, and it dissociates slightly at 

 80°; the trichloride dissociates completely in passing from solid to gas. 

 (Rec. Trav. Chim., Vii, 152.) 



The valency of boron. — Lorenz, from a study of the oxychlorides, con- 

 cludes that boron is trivaleut. Neither of the compounds BOCl nor 

 BOCI3 could be prepared; but a substance B8O11CI2, analogous in all 

 respects to several well-known salts of trivalent antimony, was obtained. 

 (Am. Chem., CCXLVii, 226.) 



The same subject is also discussed by Georgievicz from other points 

 of view ; but with the same final conclusions. He points out as evidence 

 of the trivalencyof boron the isomorphism of euclase and datolite, and 

 also describes a reaction by which when iodine is boiled with a solution 

 of borax, sodium iodate is formed. (Journ. Prakt. Chem. (2), xxxviii, 

 118.) 



The preparation of boron. — The following method is proposed by S. 

 G. Eawson : A mixture of 3^ parts of boron trioxide and 11 parts of 

 calcium fluoride is treated iu a flask with strong sulphuric acid. On 

 gently warming, a steady stream of boron fluoride is evolved, which is 

 then passed through a glass tube on which several bulbs have been 

 blown. In each bulb a small piece of potassium is placed, and these 

 are heated successively. Decomposition ensues with formation of po- 

 tassium fluoride and liberation of boron. Finally, the mass is thrown 

 on a filter and washed with water, boron remaining behind. Amor- 

 phous silicon may be easily prepared in a similar way. (Chem. News, 

 LViii, 283.) 



According to Hampe amorphous boron may also be prepared by the 

 electrolysis of fused borax between electrodes of platinum and gas 

 carbon. The free boron accumulates about the negative pole, and may 

 be separated from slag by means of water and hydrochloric acid. 

 (Berichte, xxi, ref. 827.) 



The manufacture of aluminum. — Under the patents of Mr. H. G. Cast- 

 ner, of New York, the manufacture of aluminum has been begun at 

 Uldbury, near Birmingham, England. The process revolves itself into 

 four stages. First, sodium is produced from caustic soda by reduction 

 by means of iron carbide in steel retorts at a temperature of 800°. 

 From 6 pounds of caustic soda and 5 pounds of carbide 1 pound of 

 sodium is obtained at a cost of about 18 cents. A residual product is 

 crude carbonate of soda of commercial value. Second, chlorine is pre- 

 pared by the Weldon process, the necessary hydrochloric acid being 

 supplied by the makers in return for the crude carbonate of soda above 



