264 



NA TURE 



[July 13, 1905 



in the physical section in the place of the late M. A. 

 Potier. — On the specific inductive power of metals in the 

 case of the calorific and luminous waves : Andr^ Broca. 

 The author concludes that the hypothesis of the existence 

 of a considerable specific inductive power for the metals, 

 although perhaps not sufficient to explain all the optical 

 properties of metals in detail, is at least no more in con- 

 tradiction with the facts than the hypothesis of Planck 

 that this specific inductive power is zero. — An apparatus 

 for measuring the factors, penetration, and quantity of 

 X-rays, and a radiophotometric totaliser : G. Contre- 

 moulins. Silver plates of varying thicknesses are fixed 

 on to rotating sectors, and the effect of interposing these 

 in the path of the rays upon a phosphorescent screen is 

 noticed. — The magneto-optical properties of ionoplastic 

 iron : L. Houllevigrue and H. Passa. — A method for 

 establishing coloured screens, destined to isolate certain 

 groups of special radiations : F. Monpillard. A given 

 weight of a colouring matter is diluted to a certain volume 

 with an aqueous solution of gelatin, and this poured on 

 to a glass plate of fixed area, thus giving an invariable 

 weight of colour per square centimetre. The author has 

 succeeded in producing screens giving a maximum of 

 luminosity in the green (A. 530), yellow orange (\ 588), 

 yellow (A 500), and red (A 630). — The preparation of binary 

 compounds of metals by thermochemical reactions : A. 

 Colanj. Some examples of the application of aluminium 

 powder lor reduction at a high temperature ; the products 

 are usually contaminated with aluminium and sometimes 

 with iron. — The constitution and properties of the alu- 

 minium steels : Lton Guillet. So long as the percentage 

 of aluminium is below 2 per cent., there is no marked 

 change in the properties of the steel. Up to 15 per cent, 

 the aluminium enters into solution in the iron, the iron- 

 aluminium solution thus formed not dissolving carbon. — 

 Combinations of ferrocyanides and sulphuric acid : Paul 

 Chretien. Hydroferrocyanic acid, dissolved in sulphuric 

 acid without any gas being evolved, forms a sulphonic 

 acid of the composition H3FeCy5(S03H). With fuming 

 sulphuric acid another compound is produced, FeCy^SO,, 

 the decomposition and reactions of which have been 

 studied. — A modification of the initial quality of iron and 

 steel used in the manufacture of rivets consequent on the 

 heating required in fixing ; Ch. Fremont. It is found 

 that the metal, after being heated and cooled under traction, 

 is improved in quality mechanically. — On the acid 

 ■y-aldehydes : E. E. Blaise and A. Courtot. The authors 

 have been successful in obtaining these aldedydes in a pure 

 state for the first time. An unsaturated acid is treated 

 with bromine, the dibromo-acid formed heated, a bromo- 

 lactone being then formed by the loss of hydrobromic 

 acid. Hydrobromic acid is then removed from this by 

 boiling with quinoline, and the lactone thus produced, 

 hydrolysed with an alkali, gives the acid aldehyde required. 

 — The synthesis of the lactone of erythric acid : M. 

 Lespieau. — A new method of synthesis of the monoatomic 

 and polyatomic alcohols : V. Grig^nard. This important 

 synthesis has been achieved hy the author by acting with 

 organometallic derivatives of tlie type RlVIgX on the 

 halogen derivatives of the mono- or poly-atomic alcohols. 

 The reaction takes place in two stages, 



RMgX + ClCH,.CH,.OH = RH-|-ClCH,.CH„.OMgX, 

 and this on heating gives with a fresh molecule of a 

 magnesium compound 



R'MgX'+ClCH,.CH.OMgX = 



iVIgX'CI -H R ' .CH,.CH,.OMgX. 

 The action of water on this last substance gives the alcohol 

 R.CHj.CHj.OH. Several examples of the application of 

 this synthetical method are given. — On /3-decahydro- 

 naphthylketone and /3-decahydronaphthylamine : Henri 

 Leroux. — Some new derivatives of the mesoxalic esters : 

 Ch. Schmitt. — The action of ethyl iodide on sparteine ; 

 Charles Moureu and Amand Valeur. The reaction gives 

 sparteine iodohydrate and two isomeric iodoethylates. — 

 The densities of carbonic anhydride, ammonia, and nitrous 

 oxide : Philippe A. Guye and Alexandre Pintza. The 

 results for the densities of nitrous oxide and. carbon dioxide 

 agree with those of Lord Rayleigh within tlie limits of 

 experimental error, 1/6000 to 1/19,000. Special precautions 

 Were taken in the case of ammonia to ensure the absence 



NO. I 863, VOL. 72] 



of amines, the result being 1/700 lower than the figure of 

 M. Leduc. The limiting densities for these gases were 

 worked out, and the atomic weight of nitrogen deduced 

 as 14-006. — The thermochemistry of neodymium : Camille 

 Matignon. — The influence of the elements of brown flour 

 on the extraction of the gluten and bread-making : M. 

 Ljndet and L. Ammann. — On the cause of the withering 

 of the vines in Tunis, Algeria, and the Midi : L. Ravaz, 

 — On the presence of a hydrocyanic glucoside in the 

 leaves of the elder, Sambiicus nigra : Em. Bourquelot 

 and Em. Oanjou. The elder leaf contains a glucoside 

 containing nitrogen, which, under the influence of 

 emulsin, gives glucose, hydrocyanic acid, and an 

 aldehyde. — Modifications and role of the segmentary 

 organs in some annelids : Louis Faee. — On the 

 epipodites of the Eucyphote Crustacea : H. Coutiere. 

 On the discovery of coal at Abaucourt (Meurthe-et- 

 Moselle) : Ren^ Nickles. A layer of coal, 2-65 metres 

 thick, has been found at Abaucourt, near Nomeny. It is 

 at a depth of 896 metres, and on chemical analysis proves 

 to resemble the gas coal of Saarbriick. — Observations on 

 the preceding note : R. Zeiiler. — On the geology of the 

 Pre-alps in the neighbourhood of Jaen : Robert Douville. 

 — Contribution to the tectonic of the southern Carpathians : 

 G. M. Murgoci. — On the origin of lactose. The ablation 

 of the mamm^ in lactation : Ch. Porcher. — The fixation 

 of chemical substances on living cells : MM. Charrin and 

 Le Play. 



CONTENTS. PAGE 



The Popularisation of Science. By W. R. ... 241 

 Theoretical Geodesy. By Captain W. J. Johnston, 



R.E 242 



Our Book Shelf :— 



Vacher : "The Food Inspector's Handbook." —C. S. 243 

 Marro : " Manuale dellTngegnere Eleltricista" . . . 243 

 Smith: " Poisonous Plants of all Countries " .... 243 

 Letters to the Editor : — 



The Constant of Radiation as Calculated from Mole- 

 cular Data. — The Right Hon. Lord Rayleigh, 



CM., F.R.S 243 



Proposed Observation of Mercury during the Solar 

 Eclipse. — Dr. G.Johnstone Stoney, F.R.S. . 244 



The Planet Uranus. — W. F. Denning 244 



The Exploration of the Atmosphere above the 



Atlantic. — A. Lawrence Rotch 244 



Ancient Aniarctica. — Captain F. W. Hutton, 



F.R.S 244 



The British Slugs.— Prof. T. D. A. Cockerell . . 245 

 Notes on Stonehenge. VII. — On the Dartmoor 

 Avenues. {Illustrated.) By Sir Norman Lockyer, 



K C.B., F.R.S 246 



Solar and Terrestrial Changes 249 



The Proposed College of Applied Science . . . 250 



Notes 251 



Our Astronomical Column : — 



July and August Meteors 255 



The Formation of the Martian Snow-caps . ... 255 



Recent Observation of Eros 256 



Standard Time in Various Countries ....... 256 



Harvard College Observatory Annual Report . . . 256 

 The Academic Side of Technical Training. By Dr. 



Alex. B. W. Kennedy, F.R.S 256 



Harvey and the Progress of Medical Science. By 



Dr. Frederick T. Roberts 258 



High Temperature Research on the Felspars. 



(lllusl rated.) By A. H 258 



Primitive Religious Art. By A. C. H 260 



University and Educational Intelligence 260 



Societies and Academies. (Illustrated.) 261 



