84 



NATURE 



[May 1 6, 1878 



averaging eliminates the variable efifects of cyclones and anti- 

 cyclones, on which all weather from day to day depends ; and 

 on this are based some general remarks on the use of synoptic 

 charts, not only in explaining and forecasting weather, but in 

 attacking such problems as the influence of changes of the 

 distribution of land and water on climates, and the cyclic 

 recurrence of rain or cold, (2) That deductions from averages 

 only give the facts, and not the c?.u cs, of any periodic pheno- 

 mena. The position of diurnal and other periodic variations in 

 the general scheme of meteorology is then pointed out, and it is 

 shown that their causes can only be discovered by careful study 

 of meteorograms from day to day. (3) That in taking averages, 

 phenomena are often classed as identical, which have really not 

 one common property. For instance, rain in this country is 

 associated with at least three different conditions of atmospheric 

 disturbance, and it is necessary to discriminate between these 

 kinds before meteorology can be an exact science. — On some 

 peculiarities in the migration of birds in the autximn and winter 

 of 1877-78, by J. Cordeaux. — Mr. Symons gave a verbal descrip- 

 tion of the recent heavy fall of rain, on April 10 and 11, the 

 greatest amount known to have been registered being 4*6 inches 

 at Haverstock Hill. 



Royal Microscopical Society, April 3. — Mr. 11. J. Slack, 

 president, in the chair. — A paper was read by Mr. J. W, 

 Stephenson on a new immersion object-glass which had been 

 designed by him to obviate the difficulty often experienced in 

 the accurate arrangement of the adjusting collars of high-angled 

 objectives. This new glass had a focal distance of ^ and a balsam 

 angle of 113° ; it was stated to bear very deep eye-pieces and to 

 have a very flat field. The great difficulty of obtaining an "im- 

 mersion " fluid having the same refractive index as crown glass 

 had at length been overcome by the adoption of oil of cedar 

 wood diluted with |- part of oil of fennel seeds. The objective 

 was exhibited in the room at the close of the meeting. — A paper 

 was read by Mr. Frank Crisp on the present condition of micro- 

 scopy in England, in which, as regarded a knowledge of the 

 optical and mathematical principles of the instalment, unfavour- 

 able comparisons were drawn between the workers at home and 

 abroad, and a greater degree of attention to the construction of 

 the various portions of the instrument was urged upon English 

 microscopists. — After the meeting Dr. Millar exhibited a small 

 piece of a very beautiful sponge, Acariius innominahts. Gray, 

 Mr. Curties some stained vegetable tissues, and Prof. Cleve some 

 diatoms mounted to illustrate his pamphlet. 



Geological Society, April 3. — Henry Clifton Sorby, F.R.S., 

 president, in the chair. — Rev. Albert Augustus Ilarland, M.A., 

 F.S.A., and Thomas William Shore, were elected Fellows 

 of the Society. — The following communications were read : — 

 On an unconformable break at the base of the Cambrian Rocks 

 near Llanberis, by George Maw, F.L.S., F.G.S. — On the so- 

 called greenstones of Central and Eastern Cornwall, by J, 

 Arthur Phillips, F.G.S. —The recession of the falls of St. 

 Anthony, by N. H. Winchell, communicated by J. Geikie, 

 F.R.S., F.G.S. 



Paris 



Academy of Sciences, May 6. — M. Fizeau in the chair. — 

 The death of M. Malaguti, correspondent in chemistry, was 

 commented on by M. Dumas. — The following among other 

 papers'were read : — Experiments on the heat which may have 

 been developed by mechanical actions in rocks, especially clays ; 

 and deductions regarding metamorphism, &c. (continued), by M. 

 Daubree. He rotated rapidly a circular marble plate on a 

 vertical axis, and applied to a small part of its svirface, near the 

 circumference, a small weighted and fixed marble plate, measur- 

 ing the rise of temperature of the latter with an alcohol thermo- 

 meter. In one minute, with 445 revolutions, there was an 

 increase of 4 "5°. Dry clay was also heated by friction on lime- 

 stone, &c. Apart from all eruptive rocks, the transformation of 

 rocks and appearance of new mineral species may be caused by 

 mechanical actions in the rocks transformed. — On a new memoir 

 by M. Bertin. Observations on rolling and pitching with the 

 double oscillograph, on board various ships, by M. Dupuy de 

 Lome. Inter alia, it is shown that the duration of rolls 

 varies a little (for the same vessel) with the intensity of 

 the wind, and (contrary to what one might at first think) the rolls 

 executed against the wind are always considerably shorter than 

 those in the opposite direction. — M. Chauveau was elected cor- 

 respondent in medicine and surgery, in room of the late M. 



Gintrac. — Researches proving the uDU-necessity of intercrossing 

 of the conductors serving for voluntary movements at the base of 

 the brain, or elsewhere, by M. Brown-Sequard. Two series of 

 arguments are adduced to prove that these conductors do not ' 

 intercross in the rachidian bulb nor in the protuberance ; hence 

 the inference stated. — On the mechanism and use of a differential 

 counter, by M. Valessie. This instrument gives precise indi- 

 cations for regulating the average velocity and working of a 

 machine ; it is used in several French ironclads. Its principal 

 partis a second watch, the case of which turns, by the action of 

 the engine, in the opposite direction to that of the needle. — On 

 the impossibility of propagation of persistent longitudinal waves 

 in ether, free or engaged, in a transparent body, by M. 

 Pellat. This demonstration is based (i) on the fact that 

 the reflection at the surface of an isotropous transparent 

 body, under Brewsterian incidence, extinguishes almost com- 

 pletely a ray polarised in the perpendicular plane ; (2) on the 

 principle of conservation of energy applied to such reflection, 

 supposing it takes place according to Cauchy's formula;. — On 

 the telegraphic employment of the telephone, by M. Gressier. 

 He distinguishes two kinds of disturbing sounds — that arising 

 from induction by currents in neighbouring wires, and a very 

 confused noise (heard most at night and accompanied with deflec- 

 tion of the galvanometer), which he thinks due to the wire 

 passing in different places through air layers which undergo 

 rapid and considerable variations in potential, producing various 

 currents. This suggested a means of studying variations in 

 atmospheric electricity. M. Du Moncel pointed out that these 

 latter currents had been studied with the galvanometer. — 

 On the crystallisation of silica by the dry process, by M. 

 Hautefeuille. Alkaline tungstates may with advantage be 

 used instead of phosphates (as used by M. Rose), for they 

 render obtainable at will, crystallised silica, either in the trydi- 

 mite or quartz form. — On the gold method and the termination 

 of the nerv'es in unstriated muscle, by M. Ranvier. As in 

 striated muscle, these nerves end with an arborised expansion of 

 the cylinder axis on the surface of the muscle-elements. In 

 contraction an organ co-operates which is not under the direct 

 action of the nerve-centres. — Action of morphine on dogs, by 

 M. Picard. The vasoilar dilatation and contraction of the 

 pupil result from paresis of the sympathetic nerve. — On War- 

 telia, a new genus of annelids considered wrongly as embryos 

 of Terebella, byM. Giard. — On the malacological fauna of New 

 Guinea, by M. Tapparone-Canefoi. This belongs quite to the 

 great fauna of the Indo-Pacific region, — Soda in plants, by M. 

 Contejean. More than three-fourths of terrestrial plants (not 

 maritime) belonging to regions not apparently saline contain 

 soda ; it is mostly in the subterranean portion. Aquatic plants 

 have it in all their submerged parts. The aptitude for soda 

 varies according to family, species, &c, 



.I ' . ' i ' .' .' U ' .&i '.: ■; 



CONTENTS Page 



Ths MiCROPHONS {With Illustrations) 57 



Physical Science for Artists, II. By J. Norman Lockykr, 



Y.Vi.S. {IVit/i Illustrations) 58 



The American Storm Warnings. By Jerome J. Collins .... 61 



Solar Radiation 63 



Brain 64 



Letters to the Editor : — 



The New " Oil Immersion " Object-Glass Constructed by Carl Ze's^, 



of Jena. — Rev. W.H. Dallinger ........... 65 



Science for Artists. —Tristram Ellis . 66 



Time and Longitude.— Capt. J. P. Maclear, R.N 65 



Menzlesia Caerulea.— Alex. Craig Christie 66 



"Hermetically Sealed."— W.T 66 



The Structure of Coryphodon. — Prof. E. D. Cope 6-j 



I-ightning Phenomenon. — H. J. Stavles 67 



Secondary Lunar Rainbow. — W. J. Noble 67 



Our Astronomical Colu.mn : — 



The Reappearance of Tempel's Comet, 1873, II 67 



Occultation of Mars 67 



Geographical Notes 68 



Physical Properties of Metals. By Charles R. Alder Wright, 



D.Sc. (IVith Illtistrations) . 69 



Scientific Results of D'Aluertis' Last Expedition to New 



Guinea 72 



The Rev. Robert Main, F.R.S. , Radcliffe Observer 72 



The National Water Supply. By Charles E. De Range ... 73 



Notes • • 75 



Academic Liberty in German Universities. By Prof. Helmholtz, 



F.R.S. 78 



Remarkable Changes in the Earth's Magnetism. By Capt. F. J. 



Evans, C B., F.R.S 80 



University and Educational Intelligence 82 



Scientific Serials 82 



Societies and Acade.mihs 82 



