NA TURE 



\yan. 28, 1886 



presented to the Academy by Admiral Paris. — Considerations 

 relative to the illumination of lighthouses by means of electri- 

 city, by M. Felix Lucas. It is shown that the voltaic arc pre- 

 sents two decided advantages over mineral oil : greater bril- 

 liancy and less expense. The only drawback is the somewhat 

 capricious instability of its light, a defect so inherent in the 

 nature of the voltaic arc, that at present it seems impossible 

 completely to remove it. — Note on the solar statistics of the 

 year 1885, by M. Rod. Wolf. The tabulated results of solar 

 observations made at the Zurich Observatory, and of magnetic 

 observations made at Milan, shows that the relative numljer 

 and magnetic variation have both considerably diminished at 

 about tiie same rate since the ye.ar 18S4. — On hitherto un- 

 recognised wave-lengths, by M. Langley. From his protracted 

 researches the author concludes with some reserve that the 

 radiations, whose lower limit was determined by Newton at 

 O'ooo7 mm., have nov/ been extended to o'oi5o mm., that is to 

 say, to over twenty ti.nes Newton's limit. Thus the great gap 

 that existed between the lowest known vibration of light and the 

 highest of sounds, has been partly filled up. — On the velocity of 

 the flow of liquids, by M. Th. Vautier. — On the secondary or 

 persistent luminous impressions, second note, by M. F. P. 

 Le Roux. The author concludes for the present that the 

 seat of the phenomenon, to which these persistent images 

 are due, lies about the back part of the eyeball, and 

 that probably one or more fluids play an important part 

 in its production. — Action of the sulphur of antimony on 

 the sulphur of potassium, by M. A. Ditte. — Note on a 

 new synthesis of an inactive borneol, Co,H,i;(H„02), by 

 MM. G. Bouchardat and J. Lafont. — Action of high pressure 

 on the animal tissues, by M. P. Regnard. — Influence of the 

 antesthesia produced by the inhalation of the protoxide of pure 

 nitrogen on various functions of the animal system, by M. M. 

 Laftont. This species of anaesthesia is not only more or less 

 injurious in itself, but constantly causes functional disturbances, 

 which may give rise to serious dangers, especially in certain 

 physiological conditions. — Researches on the physiological and 

 therapeutic action of acetophenone, by MM. Mairet and 

 Combemale, From their experiments the authors conclude that 

 acetophenone, which acts chiefly on the nervoiis system, is not a 

 sedative, while its healing virtues appear to be very doubtful. — 

 On the histogenesis of the eleinents contained in the ovaries of 

 insects, by Si. J. Perez. — A contribution to the study of the 

 Eocene palms of West France, by M. Louis Crie. — Note on the 

 Jurassic and Lower Cretaceous formations of the provinces of 

 Grenada and Malaga, by MM. Marcel, Bertrand, and W. Kilian. 

 These Andalusian formations appear to be of an essentially 

 Alpine character, their composition resembling those of Sicily 

 and South Tyrol. The upper layers also show strong analogies 

 with the Balearic IsKands, the .\pennines and .\lps of Lombardy. 

 — Note on the photography of speech and its reproduction by 

 oxhydric projection, by M. Leon Esquile. The author claims 

 to have succeeded, by means of the photophone, in fixing on a 

 photographic plate the modulations of the voice, afterwards 

 reproducing the words by the telephone, projecting in oxyhydric 

 light the positive image of the plate on Mercadier's selenium 

 receiver. — The election was announced of M. Boussinesq as 

 member of the Section for Mechanics, in place of the late M. 

 RoUand. — The Academy was informed by the Mayor of 

 Chamounix that the commune of Chamounix intended celebrat- 

 ing the centenary of the first ascent of Mont Blanc by de 

 Saussure in the month of August 1S87, when a monument 

 erected to his memory will be unveiled. Subscriptions for the 

 monument will be received by the Secretary of the Institute. 



Berlin 

 Physical Society, November 20, 18S5. — Dr. Gerstm.ann 

 having given a report on the " Molecular Physics " of Herr 

 Wittwer, Prof. Schwalbe delivered an address on wind-holes 

 and ground-temperatures, a theme on which he has frequently 

 before made communications to the Society. Notwithstanding 

 that he had been engaged for years in the study of ice-cavities 

 and wind-holes, the speaker had yet arrived at no conclusive 

 judgment respecting the cause of them. H.aving been pre- 

 vented in 1884 from instituting observations of his own, he 

 had collected the liter.ature of the subject, and had ascertained 

 that ice-cavities and wind-holes were very widely diffused, but 

 had not yet excited general interest to such a degree as to have 

 become the subject of continuous observations. In the summer 

 of 1885 Prof. Schwalbe made a searching investigation into the 

 cold cavities and wind-holes in the neighbourhood of Questen- 



berg, in the Southern Hartz. The gypsum here constituting the 

 main mass of the soil showed very many cavities and wind- 

 holes. The ice-cavity he had described on a former occasion, 

 with its entrance by a smooth gypsum wall, was found by him 

 this year entirely free of ice, and the temperature of the air in 

 it was, on three different visits, always between 4° and 5° C. 

 On the other side of the gypsum mountain he found a hole 

 which, on former visits, was almost entirely filled with water, 

 but was on this occasion quite dry, so that it could be examined 

 to the interior extremity. Here, too, he found a low and un- 

 commonly constant temperature of 5^ in the proximity of the 

 mouth, and of 4° at the far end. A large number of more or 

 less small holes, whence cold air issued, was found on the same 

 side of the mountain, which was almost bare, except for a few 

 fruit-trees. Occasionally these holes were very close to the 

 surface illumined by the sun, and yet their temperature, in 

 all kinds of weather, was perfectly constant and low, mostly 

 from 4° to 5°, — in one case o'. Although, too, most of these 

 cavities communicated by broader or narrower crevices with the 

 interior of the gypsum mountain, yet nowhere in them could 

 there be demonstrated any stronger current of air that might be 

 claimed as the cause of a more powerful evaporation and cooling. 

 Prof. Schwalbe, in conclusion, drew attention to two interesting 

 phenomena he had observed in the gypsum strata of the 

 Southern Harlz. These were the sinking of rivers, often 

 accompanied by loud uproar, and the occurrence of intermittent 

 lakes. The so-called " Bauerngraben '' (peasants' ditch), near 

 Rosslau, was, even in the last century, as the old contracts 

 between the two neighbouring villages proved, sometimes a 

 lake serving the one village for fishing purposes, and sometimes 

 dry land, which w.as then tilled by the other village. Several 

 channels at the bottom of the lake led to the interior of the 

 gypsum rock, nevertheless the water, when it gathered here, 

 stood for several years at a depth of from 10 to 15 metres, 

 suddenly to disappear again. In the years 1876, 1877, and 

 1S78 the " Bauerngraben " was filled with water, and since this 

 last date it had been dry land. The meteorological conditions 

 appeared to exercise no influence on this phenomenon. The 

 cause of the sudden accumulation of water, and the just as 

 sudden desiccation, was yet wholly unknown. 



CONTENTS Page 

 Louis Agassiz. By Arch. Geikie, F.R.S., Director- 

 General of the Geological Surveys of the United Kingdom 289 

 Our Book Shelf:— 



Graber's " Die ausseren mechanischen Werkzeuge 



der Thiere" 29 1 



Brown's " Animal Life on the F.arm " 292 



Letters to the Editor : — 



Iridescent Clouds. — Charles Davison. (Ilhistraled) 292 



Parallel Roads in Norway. — ^James Melvinj- . . . 293 



Dew.— H. F. P 293 



Clouds and Upper Wind-Currents over the .\tlantic 



Doldrums. — Hon. Ralph Abercromby .... 294 



Ventilation. — William Cunningham 294 



A Family of Rare Java Snakes.— Miss Catherine 



C. Hopley 295 



Vibration of Telegraph-Wires. — E. de M. Malan . 295 



Hereditary Stature.' By F. Gallon, F.R.S 295 



Deposits of the Nile Delta. By Sir J. William 



Dawson, F.R.S 29S 



Notes on the " Muir Glacier " of Alaska. By G. W. 



Lamplugh. {Ilh(slrated) 299 



Notes 301 



Our Astronomical Column : — 



The Density of Saturn's Ring 303 



The Orbit of Tethys 303 



The Orbit of lapetus 303 



A New Method of Determining the Amount of Astro- 

 nomical Refraction "^^"^ 



Astronomical Phenomena for the Week 1886 



January 31 to February 6 304 



Geographical Notes 304 



The Benefits which Society Derives from Uni- 

 versities. By D. C. Gilman, President of the 



Johns Hopkins University 305 



A New Island in the South Seas 308 



University and Educational Intelligence 308 



Scientific Serials 309 



Societies and Academies 310 



