36o 



NA TURE 



{August II, 1887 



nvestigation was undertaken with such an expectation. He re- 

 marks, however, that the conditions for a separation from a 

 mass which is strongly concentrated at its centre, are necessarily 

 very different from those which he has treated mathematically. 



However, both his investigation and the considerations ad- 

 duced here seem to show thit, when a portion of the central 

 body becomes detached through increasing angular velocity, the 

 portion should bear a far larger ratio to the remainder than is 

 observed in our satellites, as compared with their planets ; and it 

 is hardly probable that the heterogeneity of the central body can 

 make so great a difference in the results as would be necessary 

 if we are to make an application of these ideas. 



It seems then at present necessary to suppose that after the 

 birth of a satellite, if it takes place at all in this way, a series of 

 changes occur which are still quite unknown. 



Paris. 



Academy of Sciences, August i. — M. Janssen in the chair. 

 — On the silicates of thorine, by MM. L. Troost and L. Ouvrard. 

 It was lately shown by the authors that the study of the double 

 phosphates formed by thorine and zircon with phosphoric acid 

 and potassa or soda furnished no argument for associating thorine 

 with zircon. Their further researches on the combinations of 

 thorine and silica have yielded a compound substance, in which 

 this base seems to be still further removed from zircon. The 

 silicates of thorine were prepared by heating a mixture of silica 

 and thorine with the chloride of calcium used as a solvent, ani 

 by varying the conditions two silicates were obtained, differing 

 entirely in their composition and crystalline form. The crystals 

 belong to the orthorhombic system, with density 6"82 at 16° C, 

 analysis yielding i8"Oi silica and 81 "So thorine. This com- 

 pound corresponds to the formula 2ThO . SiOg (Th = 58 'i), or 

 Th'Oj . SiOa (Th' = Ii6'2). There is no isomorphism between 

 this silicate of thorine and zircon Zr02 • SiO.^ ; but here thorine 

 may be regarded as playing the part of a bioxide. This 

 conclusion has been confirmed by the recent experiments of 

 MM. Kriiss and Nilson, who, when determining the vapour- 

 density of thorium, obtained numbers approaching, but always 

 inferior to, that corresponding to the formula Th'Clj. — New 

 fluorescences with well-marked spectral bands, by M. Lecoq de 

 Boisbaudran. The new fluorescences here described are specially 

 remarkable both for the number and the position of their dis- 

 tinct rays. They are often very bright, and are obtained by 

 taking as agents the oxides of S n, Za, Z/3, and as solid solvents 

 alumina or gallina. Alumina with 1/50 of samarine shows a 

 red, an orange, and a green band, whose positions differ little 

 from those occupied by bands obtained from the inversion 

 of the induction-spark on a solution of chloride of sama- 

 rium. The red is extremely weak, the orange more 

 visible, the green easily distinguished, although less luminous 

 than the orange. — Fluorescence of spinel, by M. Lecoq de 

 Boisbaudran. The natural spinels give both a red fluorescence, 

 whose spectrum has been carefully described by M. Edm. 

 Becquerel, and also occasionally a greenish fluorescence. It is 

 here shown that the former is due to the presence of chromium, 

 the latter to that of manganese. By introducing i/ioooof MnO 

 into the composition of artificial spinel, the beautiful green 

 fluorescence gives the same green band, but considerably more 

 intense. By replacing the manganese with i/ioo of oxide of 

 chromium, there is developed a magnificent red fluorescence 

 presenting all the characters of that of the ordinary natural 

 spinels.- — Heat of formation of some crystallized tellurides, by 

 M. Ch. Fabre. It is shown that several metallic tellurides may 

 be obtained by heating in nitrogen a mixture of powdered tel- 

 lurium and filings of the metal. The tellurides of iron, nickel, 

 cobalt, and thallium not hitherto obtained, are crystallized, 

 resisting hydrochloric acid and sulphuric acid at a low tempera- 

 ture, but slowly changing in a moist atmosphere. Reduced to a 

 fine powder thty are easily dissolved in bromine and the water 

 of bromine yielding the corresponding bromide, hydrobromic 

 acid, and tp'lnrous acid. A comparison of the heats of forma- 

 tion of the crystallized tellurides and selenides seems to show 

 that in the same group, according as the equivalent weight of 

 the metalloid combined with the metal increases, the quantity 

 of heat liberated by the combination diminishes. But in order to 

 verify this hypothesis, it would be necessary to determine the heat 

 of formation of the corresponding crystallized sulphides. — On the 

 succinimidoacetic and camphorimidoacetic ethers, by MM. Alb. 

 Hallerand G. Arth. In order to obtain these ethers, the authors 

 have employed the sodified derivatives of succinimide and cam- 



phorimide, the latter behaving like its analogues in the presenc 

 the alkaline metals. — On a new isomere of benzine, by M. 

 Griner. Besides the dipropargyle belonging to the fatty se 

 discovered by M. L. Henry, the author has obtained anot 

 isomere of benzine, which does not combine with ammoni; 

 cuprous chloride, and consequently is not acetylenic. 

 simplest formula would seem to be CH.^— C = C— C=C— C 

 — Remarks in connexion with the observations of M. Gra\ 

 on the preparation of the chromates of aniline and their appl: 

 tions, by MM. Ch. Girard and L. L'Hote. The authors rep 

 that they were the first to isolate and study the bichromate 

 aniline, a crystalline salt, of which they gave the formula : 

 chemical properties, and from which they have succeeded 

 preparing certain colours such as mauveine, pheno-safrani 

 violaniline, &c. — On the effects of salting on pig's flesh affec 

 by charbon, by M. F. Feuch. The experiments here descril 

 show that even in thoroughly salted bacon the charbon is ; 

 killed, but its virulence is destroyed. — On a new microbe det 

 mining indigotic fermentation and the production of blue indi] 

 by M. E. Alvarez. The author's experiments show that ind: 

 is a product of fermentation determined by a special micrc 

 greatly resembling those of pneumonia and rhinosclerome, wh 

 also have the power of setting up indigotic fermentation. 1 

 microbe of indigo also possesses pathologic properties determ 

 ing either a passing local inflammation, or even rapid de: 

 with congestions of the viscerse and fibrine exudations. 



BOOKS, PAMPHLETS, and SERIALS RECEIVE: 



A New Mode of Geometrical Demonstration, with Examples ; D. Mai 

 (Brown, Aberdeen). — Terra: A. A. Anderson (Reeves and Turner) 

 Annales de TObservatoire de Nice, tome ii. (Paris). — Food Adulte 

 tion and its Detection : J. P. Battershall (Spon). — Electricity : W. Lard 

 (Longmans). —British Dogs, Nos. 9 and 10: H. Dalziel (Gill). — Bees a 

 Bee-keeping, vol. ii. parts 9, ip, 11: F. R. Cheshire (Gill).— McGill U 

 versity Annual Calendar, Faculty of Medicine (Montreal).— On the Edui 

 tion of Engineers : H. Dyer (Munro, Glasgow). — Hints to Meteorologii 

 Observers, 2nd edition (W. Marriott (Stanford). — Archives Neerlandai; 

 des Sciences Exactes et Naturelles, xxi. (Harlem). — Brain, part xxxv: 

 fMacmillan). — Quarterly Journal of the Royal Meteorological Society, .\p 

 (Stanford). — Meteorological Record, vol. vi. No. 24. vol. vii. No 25 (Stj 

 ford). — Annalen der Physik und Chemie, i8'J7, No. 8/» (Leipzig). — BeiblatI 

 u den Annalen der Phy.sik und Chemie, 1887, No. 7 (Leipzig). 



CONTENTS. PAG 



The Topography of Galloway. By Joseph Lucas 3; 

 Our Book Shelf :— 



Candler: "The Prevention of Consumption."— Dr. 



E. Klein, F.R.S y^ 



Millis : " Metal Plate Work " 3.) 



Lindley : " Walks in the Ardennes " ....... 34 



Letters to the Editor : — 



The Parietal Eye in Fishes. — ^J. Beard 34 



Physiological Selection. — Dr. George J. Romanes, 



F.R.S 34 



The Droseras. — ^J. Rand Capron 34 



Comrades. — E. R 34 



A New Cosmogony. II. By A. M. Gierke .... 34 

 Music in Nature. By Dr. William Pole, F.R.S. . . 34 

 The British Museum (Natural History Branch). 



By Dr. Henry Woodward, F.R.S 34 



Notes 34 



Astronomical Phenomena for the Week 1887 



August 14-20 35 



New Guinea Exploration ^\ 



The Institution of Mechanical Engineers WtA 



The Structure and Progress of the Forth Bridge. HI 



By E. Malcolm Wood fli 



The Machinery employed at the Forth Bridge HI 



Works. By William Arrol 35* 



The Chemistry of the Rare Earths. By A. E. 



Tutton IW 



Societies and Academies 3i.\ 



Books, Pamphlets, and Serials Received 



