592 



NA rURE 



{April 17, 1884 



pleochroic ; and they exhibit the oblique extinction in basal 

 sections first pointed out by Mr. Whitman Cross, and which 

 is characteristic of triclinic and not of monoclinic ciystals. A 

 careful examination of the question has led the author to con- 

 clude that the mineral which has lately been regarded as a 

 rhombic pyroxene (probably hypersthene) is really only ordi- 

 nary augite cut parallel to the optic axis. He does not regard 

 the property of pleochroism as distinctive of hypersthene, while 

 the absence of a brachypinacoidal cleavage and the presence 

 of 10 per cent, of lime in the mineral forbids our referring it 

 to that species. The other abundant minerals in these augite- 

 andesites are magnetite, which is always present, and quartz, 

 which occurs in some of them, both as a primary and a second- 

 ary constituent. Hornblende is very rare in these rocks, and 

 when present the peripheral portions of the crystals are seen 

 to be converted into augite, probably by the action of the 

 caustic magma upon them. Enstatite is rare in these rocks, 

 but apatite is always found in them, while tridymite occurs 

 not unfrequently. The -author described a number of struc- 

 tural variations in the augite-andesite from different localities. 

 Among the most interesting is a variety containing as much 

 as 69 per cert, of silica. Among the less abundant rocks are 

 the enstatite-andesite, the quartz-augite-andesite, and the horn- 

 blende-andesites. The plagioclase-basalts of Japan can only 

 be distinguished from the augite-andesites by the presence in 

 them of olivine. Magma-basalts are rare, most of the varie- 

 ties being of the dolerite type ; but under the name of " basalt- 

 lavas" the author describes varieties with a glassy base. In 

 an appendix some account is given of a number of pre-Ter- 

 tiary rocks, including granite, one variety of which contains 

 the new mineral, reinite, of Fritsch (the tetragonal form of 

 the ferrous-tungstate), quartz-mica-diorite, diorite-porphyry, and 

 diabase. 



Victoria Institute, April .7. — A paper was read by the Rev. 

 J. M. Mello, F.G.S., on the prehistoric flint implements at 

 Speinnes, implements used by man before the mammoth and 

 rhinoceros had disappeared in Europe. The author described 

 the works at Speinnes, and afterwards said there was one ques- 

 tion, namely, were these early men of Europe always in the 

 condition in which they appear to have been living, or were they 

 offshoots of the parent stems of humanity, and had their ancestors 

 no higher civilisation ? 



Edinburgh 



Mathematical Society, April 10. — Mr. Thomas Muir, 

 F.R..S.E., president, in the chair. — Dr. Alexander Macfarlane, 

 F. R. S.E., submitted a note on simple, combination, and cumu- 

 lative voting, after which Mr. A. J. G. Barclay read a paper on 

 the teaching of geometry. — Mr. Muir gave an explanation of an 

 algebraical theorem communicated by Prof. Tait to the January 

 meeting of the Society. 



Manchester 



Literary and Philosophical Society, February'5. — Charles 

 Bailey, F.L.S., in the chair. — On the introduction of coffee iuto 

 Arabia, by C. Schorlemmer, F.R.S. 



February 19.— H. E. Roscoe, Ph.D., LL.D., F.R.S. , &c., 

 president, in the chair. — Notice of the geology of the Haddun 

 district, eight miles siuth-west of Ballarat, Victoria, by K. M. 

 Krause, Piofessor of Geology in the School of Mines, Ballarat. 

 Communicated by the President. 



Paris 

 Academy of Sciences, April 7. — M. Rolland in the chair. 

 — An exact or highly a])proximate calculation of the thrust of 

 sandy masses against their retaining walls, by M. de Saint- 

 Venant. — On the specific heats of water and of carbonic acid at 

 very high temperatures, by MM. Berthelot and Vieille. — Note on 

 Brioschi's theorem respecting symmetrical functions; by i\I. 

 Sylvester. — Documents relating to the liquid air condensers for 

 several years employed in the piercing of the Mount Cenis 

 Tunnel, by M. A. de Caligny. — Tabulated results of the various 

 circumstances attending electric discharges during the thunder- 

 storms that occurred in France during the second half of the year 

 1883, communicated by the Minister of the Posts and Tele- 

 graphs. — Telegraphic determinations of the differences of longi- 

 tude in South America, by M. de Bernardieres. — Charts of the 

 atmospheric movements passing over Europe in the various 

 regimes ; remarks on their application to the prediction of storms, 

 by M. A. Poincare. — Note on the influence of luni-solar attrac- 

 tion on the action of pendulums, by M. A. Gaillot. — On 



the solar spots observed in Rome during the first three months 

 of the year 1884, by M. P. Tacchini. — Note on the halos of 

 diffused light observed round the sun on March 31 at Auteuil, 

 by M. Ch. Moussette. — On the aspect presented by the Pons- 

 Brooks comet on January 13, 1884, by M. L. Cruls. — Note on 

 an error committed in detemiining the exact moment of the 

 chief eruption at Krakatoa last year, by M. A. A. Buijskes. 

 This disturbance, generally stated to have occurred a few minutes 

 before noon on August 27, really took place exactly at eight 

 o'clock in the morning of that day. Hence the calculations of 

 the velocities of marine and atmospheric currents based on the 

 former date must be rectified accordingly. — On the ]>rinciple of 

 the prism of greatest thrust laid down by Coulomb in the theory 

 of the equilibrium of sandy masses, by M. J. Boussinesq. — On the 

 quaternary quadratic formulas, and on the corresponding hyperabe- 

 lian groups, byM. E. Picard. — On the theory of quaternions in con- 

 nection with Prof. Sylvester's recent solution of equations in which 

 all the given quaternions are found on the same side as the 

 quaternion sought for, by M. Ed. Weyr. — Note on the applica- 

 tion of Faraday's law to the''study of the conductivity of saline 

 solutions, by M. E. Bouty. — Note on the verification of the laws 

 of transverse vibrations in elastic rods, by M. E. Mercadier. — 

 Fresh experiments in the liquefaction of hydrogen ; solidification 

 and critical point of pressure for nitrogen, by M. K. Olszewski. 

 — On the chief circumstances attending the transformation of super- 

 heated octahedral sulphur into prismatic sulphur, by M. D. Gernez. 

 — Quantitative analysis of the phosphoric acia found in arable 

 lands and in rocks, by M. Ad. Carnot. — On the artificial produc- 

 tion of fayalite, by ^I. Alex Gorgeu. The author's experiments 

 show that the protochloride of iron, fused with silica, produces 

 fayalite under conditions in which the chloride of manganese 

 yields tephroite. It appears incapable of producing a bisilicate 

 corresponding to rhodonite, and yields chlorosilicate of iron with 

 difficulty. Highly crystallised magnetite and hausmannite may 

 be obtained under analogous conditions by the fusion iif their re- 

 spective chlorides in contact with the air. — Claim of priority of 

 discovery in connection with recent communications on the 

 vitality of virus and of the yeast of beer ; letter addressed to the 

 President by M. Melsens. — Researches on the incubation of 

 hens' eggs in confined air, and on the part playevl by ventila- 

 tion in the development of the embryo, by M. C. Dareste. — On 

 the variations of electric excitability and of the period of latent 

 excitement in the brain, by M. H. C. de Varigny. — Note on a 

 Siberian pseudo-meteorite, by M. Stan. Meunier. 



CONTENTS pagp 



Samoa. By J. A. Farrer 569 



Voice, Song, and Speech. By Dr. W. H. Stone . 570 

 Our Book Shelf:— 



Casey's "Sequel to the First Six Books ..f the 



Elements of Euclid " 571 



Ricketts's " Ores of Leadville, and their Mode of 



Occurrence, &c." 5"' 



Wiesner"s " Elemente der Oi'ganographie, Systematik. 



und Biologic der Pflanzen " 572 



Letters to the Editor : — 



On the Motion of Projectiles. — E. Ristori .... 572 



Christian Conrad Sprengel. — Dr. H. A. Hagen . . 572 

 Salt-water Fish-Types in Fresh Water. — Prof. Theo. 



Gill 57; 



"The Axioms of Geometry." — Prof. O. Henrici, 



F.R.S 57; 



Wild Duck laying in Rook's Nest. — ^John H. Will- 

 more 57 •; 



The Remarkable Sunsets.— S. E. Bishop .... 57,; 



Cats on the District Railway. — E. de M. Malan . 57.; 



The Geodetic Survey of the United States .... 57.; 



Agriculture in Sussex 575 



Socotra 57.^ 



The Three Hundredth Anniversary of the University 



of Edinburgh, liv Prof. G. Chrystal 577 



The Congo. I'.y Prof. A. H. Keane (With lUiis'.ra- 



tinns) 57'' 



Notes 5^' 



Geographical Notes 5S4 



Volcanic Ashes and Cosmic Dust. Bv John Murray 



and A. Renard (l/V/'i ////H/ra/;>«,() .' 5S5 



University and Educational Intelligence 500 



Societies and Academies 591 ■ 



