Chemistry and Physics. 67 



ammonia being 71*93, 7 1*60, 71 '2 8 and 71'] 8. Theory requires for 

 NH 3 Li, 29-16 of lithium and 70*83 of ammonia. It is much less 

 soluble in liquid ammonia than the sodium compound. The metal 

 calcium exposed at 15° to a current of ammonia gas takes a yel- 

 lowish-brown tint, becomes heated and increases in volume. At a 

 temperature between 15° and 20° only a solid compound is formed, 

 which takes fire in contact with the air and which fixes liquid 

 ammonia and becomes pasty, being then soluble in the liquid. 

 Like lithium, it gradually decomposes at the ordinary tempera- 

 ture, yielding transparent crystals of amide (NH 2 ) 2 Ca and evolv- 

 ing hydrogen. On analysis calcium-ammonium gives numbers 

 agreeing with the formula (NH 3 ) 4 Ca. — C. P., cxxvii, 685-692, 

 November, 1898. g. f. b. 



5. On the Spectra of Iodine. — The results of a measurement 

 of the lines in the emission and absorption spectra of iodine from 

 wave-length 3030*5 to wave-length 6191, expressed in Angstrom 

 units, have been given by Konen. As is well known, either a 

 line spectrum or a band spectrum can be obtained in a vacuum 

 tube. The latter is composed of two different portions which 

 may be designated as B R and B v ; the former of these, B R , is iden- 

 tical with the absorption band spectrum, while B v is not. When 

 the discharge is very intense, however, B R disappears, while B v 

 increases in intensity ; so that the author is inclined to the view 

 that B R is due to the ordinary iodine molecules, and B v results 

 from dissociation. In the line spectrum also, two series may be 

 distinguished, but it is quite possible that in this case the second 

 series may be produced by an impurity. Tables of the wave 

 lengths are given in the paper. — Ann. Phys. Chem., II, lxv, 257- 

 286, 1898. G. F. B. 



6. A Manual of Chemical Analysis, Qualitative and Quanti- 

 tative; by G. S. Newth, Demonstrator in the Royal College of 

 Science, London ; 8vo, pp. xii, 462. New York, 1898 (Longmans, 

 Green and Co.). — The author tells us in the preface to his book 

 that he has " done his best to make it as little of a cram-book as 

 possible, but has endeavored to teach analytical chemistry as well 

 as analysis — that is, the theoretical as well as the practical side of 

 the subject." Book I treats of Qualitative, Book II of Quantita- 

 tive Analysis. The quantitative work is divided into gravimetric 

 methods, including electrolysis, and volumetric methods, includ- 

 ing gas analysis; special methods following these. The great 

 convenience of having the leading facts well set forth in a work 

 of moderate size, for the use of students taking short courses, is 

 well exemplified in this manual. The portion on volumetric work 

 seems especially good. g. f. b. 



7. Stratified Brush Discharges in Atmospheric Air. — M. 

 Toeplee has described a species of stratification in brush dis- 

 charges (Wied. Ann., lxiii, p. 109, 1897) and the present paper is 

 a continuation of his studies in this direction. A sixty-plate 

 Toepler-Holtz machine was employed, and it was found that the 

 increase of potential-difference was closely proportional to the 



