500 Scientific Intelligence. 



be formed. Experiments with pure sodium nitrite showed that 

 there was no odor of nitrous gases in the nitrogen escaping from 

 the reaction with hydrazine sulphate, and that the solution after 

 the reaction was complete gave no test for nitric acid with diphe- 

 nylamine in concentrated sulphuric acid. — Zeitschr. anorgan. 

 Chem., lxxiv, 52. h. l. w. 



3. The Chemical Constitution of Ilmenite. — W. Manchot has 

 made analyses of a massive titanic iron ore from Ekersund in 

 Norway and a crystal of ilmenite from the Urals. The results in 

 the two analyses are very dissimilar, and the ilmenite analysis is 

 incomplete, but the latter is of some interest because the ferric 

 oxide was determined by dissolving the substance, out of contact 

 with air, in hydrochloric acid and using iodimetry. This deter- 

 mination indicates that the ratio of Ti0 2 to FeO approaches 1:1. 

 This is used as an argument in favor of the ilmenite formula 

 Ti0 2 .FeO, and in opposition to the view that it is a mixture of 

 Ti 2 3 and Fe 2 3 . It appears that the same formula was indi- 

 cated much more satisfactorily by the work of Penfield and Foote 

 (this Journal, iv, 108, 1897). The author has attempted to show 

 by direct experiment that Ti 2 3 is not contained in the mineral 

 by demonstrating that the powdered samples when boiled either 

 with alkalies or acids evolve no hydrogen gas. Although the 

 author considers these experiments to be conclusive, it does not 

 appear that this is the case, for if a titanous salt and a ferric salt 

 were formed at the same time it is perfectly well known that, at 

 least in acid solution, the ferric salt would be reduced, and if the 

 ferric salt were in excess no hydrogen could possibly be given off. 

 In the case of alkalies, if any reaction at all occurred, it might 

 happen that nascent hydrogen would reduce ferric oxide instead 

 of forming a gas. — Zeitschr. anorgan. Chem., lxxiv, 79. 



H. L. W. 



4. Determination of Alkalies in Silicates. — For this determi- 

 nation E. Makinen has used fusion with about 10 parts of cal- 

 cium chloride in the place of J. Lawrence Smith's method. The 

 platinum crucible in which the fusion is made is placed in a hole 

 in a piece of asbestos board in such a way that only the lower half 

 of the crucible comes in contact with the flame. This part of the 

 crucible is gradually brought to a full red heat by means of a 

 Teclu burner, and so maintained for 25 or 30 minutes. The 

 treatment is then similar to that usually employed in Smith's 

 method. Specially prepared calcium chloride was required, as 

 the commercial product was found to contain alkalies. The 

 results with several feldspars and rocks were good, but it appears 

 to the reviewer that, on account of the very large amount of cal- 

 cium chloride going into solution, which necessitates a double 

 precipitation of calcium carbonate, the process will not replace 

 the usual one. — Zeitschr. anorgan. Chem., lxxiv, 74. h. l. w. 



5. A Dictionary of Applied Chemistry ; by Sir Edward 

 Thorpe, C.B., LL.IX, F.R.S., assisted by Eminent Contributors. 

 Revised and Enlarged Edition in Five Volumes. Volume I (A- 



