152 



NATURE 



\pec. 14, 1876 



been going on. The effect of this local cause would, however, 

 not be local, but would contribute to increase the charge of the 

 earth as a whole — as one jar in fact, so that the earth as a whole 

 might, for a short period, be increasing its charge — the local 

 charging causes Ijeinjj in excess of the local discharges. Next, 

 would not this excessive charge appear to increase the barometric 

 pressure of the air over the whole earth ? On the other hand we 

 may imagine the discharging influences to be sometimes in ex- 

 cess of the charging causes, and then the electrical separation of 

 the earth jar would diminish, and the barometric pressure of the 

 air appear to diminish also. These remarks are put forward not 

 as a formal theory, but rather with the view of inviting discus- 

 sion. In considering a fact such as that brought forward by 

 Mr. Broun, we must first endeavour to explain it by the opera- 

 tion of some known cause. I have therefore introduced a force 

 which we know to exist, and a mode of operation which is not 

 at first sight improbable. It may be thought that electrical 

 separation can hardly be great enough to produce a sensible 

 barometrical difference. Let this be proved, and a point will 

 be gained by the dismissal of v/hat seems at first sight a possible 

 hypothesis. Meanwhile — to bring these remarks to a practical 

 issue — might it not be well to examine the records of atmo- 

 spherical electricity corresponding to the dates of Mr. Broun's 

 observations with the view of ascertaining whether Mr. Broun's 

 results are in any way connected with the electrical state of the 

 earth's envelopes ? 



Geneva 



Physical and Natural History Society, October 5. — 

 Prof. Plantamour communicated to the Society the continuation 

 of his investigations into the climate of Geneva, dealing espe- 

 cially with winds, cloudiness, and rain. As to winds, he has 

 obtained for the last fifteen years a confirmation of the previous 

 results, viz., that the local winds at Geneva play an important 

 part in consequence of the action of the lake ; the land breeze 

 at the lake giving a south wind, prevails in the warm season, 

 especially during the morning and evening hours. Generally 

 the south wind prevails from April to October, while the bise, or 

 north wind, prevails from November to March. "With regard to 

 cloudiness, M. Plantamour has established that the daily variation 

 changes in a notable manner with the season. In winter the 

 minimum of nebulosity occurs at 4 P.M., while in summer it is 

 the afternoon hours that are most overcast. In winter it is the 

 night cold which is the principal cause of clouds ; in summer 

 the afternoon heat. December is the most cloudy month ; July 

 and August are the clearest months, with difference from one 

 year to another. Examining next the period of fifty years from 

 1826 to 1875, in reference to the quantity of rainfall, M. 

 Plantamour arranges the years into very dry, dry, wet, and very 

 wet, according to the proportion of rain which they have given, 

 as compared with the mean. It follows from this classification 

 that years of different qualities succeed each other in an order 

 entirely irregular ; that a year may be followed as likely by a 

 similar as by a different or very different year in point of 

 humidity. However, there are series of years in which the 

 rainy prevail, and others in which the dry prevail. Thus, from 

 1826 to 1837 there were eight dry years and four wet ; from 

 1838 to 1856, fourteen wet years and five dry years ; from 

 1857 to 1865, six dry years and three wet. Still there is no 

 regularity, no periodicity in the return of these dry and wet 

 epochs, nothing especially which we may connect with the 

 eleven-year period of sun-spots. 



Paris 



Academy of Sciences, December 4. — Vice-Admiral Paris 

 in the chair. — The following papers were read : — On a note of 

 P. Secchi relative to the formation of hail, by M. Faye. He is 

 surprised at P. Secchi giving out as new the idea of trombes 

 with vertical axes bringing down cold air from the upper regions. 

 He urges the sun-spot analogy.— Indices of a new genus of 

 edentate mammifera, fossil in the Saint Ouen Eocene deposits, 

 by M. Gervais. The peculiarities of some of the fragments 

 (chiefly a calcaneum, and metatarsal or metacarpal bones) are 

 described. The animal seems to have been like Macrotherium 

 and Ancylotheriunt in some respects, unlike in others. M. 

 Gervais names the genus Pernatherium, and the species P. 

 rugosum, in allusion to the wrinkles on many of its bones. — 

 Preparation of alcohol by means of sugar contained in the leaves 

 of beets, by M. Pierre. He calculates that 34 kilogrammes of 

 juice of the leaves may yield o'igS litre of absolute alcohol 



the leaves of i hectare about 173 litres. At the. moment of 

 removal the leaves contained nearly 350 kilogrammes of sugar 

 per hectare. — M. de Lesseps, presenting a brochure on Africa and 

 the Geographical Conference at Brussels, explained the scheme 

 of the Kintj of Belgium of an international association for opening 

 and civilising Central Africa. — On the employment of iodide of 

 potassium in lead colic and paralysis, according to M. Melsens' 

 method, by M. Jacobs. The patient takes i gramme a day, 

 and increases the dose by I gramme up to 6, 8, 10, 12, or 15 

 grammes, then returning gradually to the initial dose. The 

 more iodide he can bear the sooner is he cured. — Researches on 

 the devitrification of vitreous rocks, by M. Meunier. M. Levy's 

 facts do not seem to him to furnish any argument against the 

 production of crystalline rocks at expense of vitreous rocks, by 

 way of devitrification. — Results obtained by the decortication 01 

 vine stocks, by M. Sabate. — Report on the experiments made 

 by the Paris-Lyons-Mediterranean Company for combating phyl-; 

 loxera, by M. Marion. They commend sulphide of carbon an4 

 sulphu-carbonates, which should be applied when the products 

 of the winter eggs have descended to the roots, i.e., about July. 

 The old phylloxera of the roots is thus treated as well. — Scale 

 of platinised iridium (4 m.) of the International Geodesic Asso- 

 ciation, by M. Matthey. Observations on this communication, 

 by M. H. Sainte-Claire Deville, also by MM. Tresca and 

 Dumas. M. Tresca remarked on the high density, about 21 '50. 

 If it contained only 10 per cent, of iridium, ythf^ of rhodium, and 

 TTnnr o^ ruthenium, the manufacture of metals of platinum must 

 have been greatly improved since 1872. — Observation of a new 

 star in the constellation of Cygnus, by M. Schmidt, director of 

 the Athens Observatory. — Observations of the planet (169) Zelia, 

 discovered at the Observatory of Paris, Sept. 28, 1876, by MM. 

 Henry. — On the application of the methods of mathematical 

 physics to the study of bodies terminated by cyclides, by M. 

 Darboux. — New method for studying calorific spectra, by M. 

 Aymonnet. With a constant heat-source, one may, even with a 

 pretty large aperture of thermopile, find approximately the quan- 

 tities of heat in spectral parts smaller than the aperture. Thus, 

 suppose the pile is I mm. in aperture, you advance it (say) two- 

 tenths of a millimetre at a time, noting each time the portion of 

 spectrum passed from and the new part embraced. This is 

 the principle of the method ; by which M. Aymonnet gets 

 some interesting results. The minima present a remarkable 

 periodicity, and are displaced when the temperature of the 

 source vaiies or a liquid screen is interposed. — Productions ot 

 carbonate of soda by the action of chloride of sodium in solution 

 on carbonates of lime and magnesia, in presence of vegetable 

 matters, by M. Pichard. — Researches on sensation compared 

 with motion, by M. Richet. He formulates this general law as 

 applicable both to muscles and to sensitive nerve centres : the 

 number of excitations necessary to produce a perception or a 

 motion is inversely proportional to the intensity and frequency of 

 these excitations. — Experimental researches on the cardiac, vas- 

 cular and respiratory etfects of painful affections, by M. Franck. 

 The immediate effect on the heat is always a stoppage or retarda- 

 tion ot the beats. —On the form and reciprocal relations of the 

 cellular elements of loose connective tissue, by M. Renaiit. — 

 Habits of fishes ; the gourami and its nest, by M. Carbonnier. 



CONTENTS 



Page 



McLennan's Studies in Ancient History. By Sir John Lub- 

 bock, Bart., F.R.S 133 



Our Book Shelf : — 



" Science in Sport made Philosophy in Earnest " 134 



Smith's " Mushrooms and Toadstools " 134 



Barkley's 'Between the Danube and the Black Sea; or Five 



Years in Bulgaria "...... 134 



Beveridge's ' ' District of Bakarganj ; its History and Statistics " . 135 

 Letters to the Kditor : — 



Sea Fisheries.— E. W. H. Holdsworth . 135 



Examinations in Science.— W. Baptiste ScooNES 137 



The Rocks of Charnwood Forest —Rev. T. G. Bonney . . 137 



Self- Fertilisation in Flowers. — Thomas Meeham 138 



On Supersaturated Solutions. — J. G. Grenfell 138 



Karl Ernst von Baer 138 



David Forbes i39 



The Glaciation of the Shetland Isles. By John Horne . . 139 



Prim^.val Switzerland (tf'jM //^?<^^?-rt.'z>?«) ........ 140 



The Brain of the Gorilla. By G. D. Thane [With Illustrations) 147 

 Museum Specimens for Teaching Purposes. By Prof. W. H. 



Flower, F.R.S ^44 



Our Astronomical Column : — 



A New Star in Cygnus 146 



The Opposition of Mars, 1877 . ^47 



Notes 147 



Societies and Academies , . 150 



