72 



NAiVRE 



[May 19, 1892 



thermal value of the replacement of H by Na in a tertiary alcohol, 

 by M. de Forcrand. 



C4Hi(,0 sol. +Na sol. = H gas + C4HgONa sol. . . . +27-89 cal. 



For secondary and primary alcohols the values are respectively 

 + 2975 and + 32*00 cal. — Establishment of the fundamental 

 formulae for the calculation of maximum moments of inertia (of 

 molecules), by M. G. Hinrichs. — The constitution of the 

 hydrocarbon derived from perseite, by M. L. Maquenne. — 

 The chemical properties and analysis of acetyl fluoride, by 

 M. Maurice Meslans. (See Notes.) — The acid antimonite of 

 pyrocatecbol, by M. H. Causse. — Action of organic acids on 

 acetylenic hydrocarbons, by MM. A. Behal and A. Desgrez. — 

 On the stranding of a whale mentioned in the 113th Olympiad, 

 by M. G. Pouchet. — On the physiological constitution of the 

 tubercles of potatoes in relation to the development of shoots, 

 by M. A. Prunet. — On the old glaciers of the Cordilleras of 

 Chili, by M. A. G. Nogues. — On the genus Megapleuron, by 

 M. Leon Vaillant. — On a Dicotyledon found in the Upper 

 Cretaceous on the environs of Sainte-Menehould (Marne), by 

 M. P. Fliche. 



Amsterdam. 

 Royal Academy of Sciences. April 29. — Prof, van de 

 Sande Bakhuyzen in the chair. — Mr. Behrens dealt with the 

 microscopic structure of alloys. Crystallization is a common 

 phenomenon in metals. The least crystalline are pure Al, Cu, 

 Ni, when cast without overheating. Rapid cooling has no other 

 effect than to make the crystals of smaller size. Pure Ag does 

 show always crystallization, if properly etched. In alloys 

 crystallization is more easy and perfect than in unalloyed metals. 

 When I gr. of Cu, alloyed with 2 mgr, Ag, is melted and slowly 

 cooled, it will be found chequered by minute threads of an alloy 

 rich in silver. All types of structure found in crystalline rocks 

 can be reproduced in alloys. The most common is rectangular 

 wickerwork, less common are isolated clusters of crystals (alloys 

 with few crystals of high melting-point, as in Zn + 10 per cent. 

 Pt, Cu + 10 per cent. Co). Mechanical stress does not destroy 

 the crystalline structure. A fibrous or lamellar structure is set 

 up, corresponding with planes of sliding or shearing in inter- 

 crystalline matter, and under heavy stresses partly due to flatten- 

 ing and stretching of crystals. By annealing, alloys of Cu with 

 Ni can be made to crystallize even as soft iron, thereby becoming 

 even brittle. — Mr. Schoute treated of movement in space 

 of n dimensions. — Mr. Bakhuis Roozeboom treated of the 

 hydrates of iron perchloride. — Mr. Kapteyn made a communi- 

 cation on the distribution of the stars in space. He has com- 

 pared the spectral type of stars of different proper motion. For 

 this latter element the list given by Mr. Stumpe in the Astr. 

 Nachr., Nos. 2999-3000, was used ; the spectral types were 

 taken from Mr, Pickering's "Draper Catalogue." 476 stars not 

 fainter than 7'om. were found common to the two catalogues. 

 Together with these, 115 other well-determined stars were used, 

 taken from Bradley's catalogue, whose proper motion according to 

 Auwers's reduction is less than 0*0035. in R. A., and less than o""03 

 in Deck This material, arransjed according to the amount of the 

 proper motion, leads to the following conclusion : — The region of 

 the universe nearest to our planetary system contains nearly ex- 

 clusively stars of the second type (Pickering's CI. E-L) ; with 

 growing distances the number of stars of the first type 

 (Pickering's CI. A-D), relatively to the number of those of the 

 secondtype, increases gradually and approximately in inverse ratio 

 with the proper motion {i.e. very probably in direct ratio with the 

 distance) in such a way that equality of number is reached at a 

 distance corresponding to a proper motion of o" "08 or thereabout. 

 At distances still greater, the stars of the first type begin to pre- 

 ponderate, and they are more than twice as numerous as those of 

 the second type at the mean distance of those of Bradley's stars, 

 whose proper motion is insensible. From the differences between 

 visual and photographic magnitudes Mr. Kapteyn shows that 

 analogous results will most probably be found for the southern 

 hemisphere as soon as a catalogue of southern star spectra is 

 published. The investigation further indicates, though far 

 less clearly, for the centre of symmetry of the system, a situation 

 at a certain distance from the sun in the direction of 23 hours of 

 R.A. Lastly, it is demonstrated that, even for distances corre- 

 sponding to proper motion of o"'l6 to o""30, no accumulation of 

 stars towards the plane of the Milky Way is shown ; that for 

 distances considerably greater this accumulation cannot be con- 

 siderable, and that the Milky Way must be attributed therefore 



NO. I I 77, VOL. 46] 



to stars at enormous distances. — ^Mr. Franchimont communicated 

 an experiment used by him in his College during several years to 

 show that the presence of hydriodic acid is necessary for the 

 formation of iodine starch. 



GOTTINGEN. 



Royal Society of Sciences. — The following papers of 

 scientific interest have appeared in the Nachrichten since 

 November 11, 1891 :— 



November li, 1891. — E. Riecke and W. Voigt, the piezo- 

 electric constants of quartz and tourmaline. 



November 25. — Franz Meyer, on a persistence-theorem for 

 algebraic equations. Starting from the theorem that, for a cubic 

 equation, the sum of the number of real roots for the cubic and 

 its Hessian together is always three, the author finds for any 

 equation of odd order a series of forms such that the sum of the 

 real roots of the equation and these forms together is always the 

 same. — Otto Burger, preliminary communication on the Neiner- 

 tina of the Gulf of Naples. — Otto Wallach, on certain new 

 hydrocarbons with a ring of carbon-atoms. 



December 23, — Alfonso Sella, contribution to our knowledge 

 of the specific heats of minerals. — Frobenius, on potential 

 functions whose Hessian is zero. — Schonflies, remark on Hu- 

 bert's theory of algebraic forms. — Alberto Tonelli, remark on 

 the solution of quadratic congruences. — P. Drude and W. 

 Nernst, on fluorescence-effects of stationary light-waves. 



January 27, 1892. — Heinrich Burkhardt, the reduction of the 

 twenty-seven lines of a cubic surface to the transformation prob- 

 lem of the hyper-elliptic functions for p = 2. — David Hilbert, 

 on the theory of algebraic invariants. — Clemens Hartlaub, on the 

 Anthojiiedusa. 



March 9. — ^J. Disse, changes in the renal epithelium during 

 secretion. — Kroeker, the dependence of the specific heat of 

 boracite upon the temperature. 



CONTENTS. PAGE 



The Tell el-Amarna Tablets in the British Museum 49 



A Text-book of Physics 52 



Our Book Shelf:— 



Goodfellow: " The Dietetic Value of Bread " .... 54 



Richardson : " Graduated Mathematical Exercises " . 54 

 "Bihliothek des Professors der Zoologie und vergl. 



Anatomie, Dr. Lud wig von Graff, in Graz" .... 54 



Roberts : " The Canadian Guide-book " 54 



Letters to the Editor :— 



A Question in Physics.— -Prof, H. A. Hazen .... 55 



Aurora. — H. Geelmuyden 55 



Wave-Propagation of Magnetism.— Fred. T. Trouton 56 

 Correction in "Island Life."— Dr. Alfred R. Wal- 

 lace 56 



The International Conference on Chemical Nomen- 

 clature. By Prof. H. E. Armstrong, F R.S. ... 56 

 The Geology of Barbadoes. By A. J, Jukes Browne 



and J. B. Harrison 59 



Eduard von Regel 60 



Notes 61 



Our Astronomical Column :— 



Latitude Observations at Waikiki 64 



Motion in the Line of Sight 64 



The Late Partial Eclipse of the Moon 64 



Declinations of Stars for Reduction of Variations in 



Latitude 65 



Comet 1892 Denning (March 18) 65 



Comet 1892 Swift (March 6) 65 



Geographical Notes 65 



The Variations of Terrestrial Latitudes. By W. J. L. 65 



Magnetic Variations. By William Ellis 67 



Scientific Serials 67 



Societies and Academies 69 



