284 



NA TURE 



\_Jan. 



in the region of the loins, but is completely absent from the 

 blood and liver. Its study may yield important results for the 

 treatment of cholera, and must pos-ess great interest for toxolo- 

 gists. — Observations of Encke's comet made at the Paris 

 Observatory (equatorial of the West Tower), by M. G. Bigour- 

 dart. — Note on the theory of periodic transformation-, by M. S. 

 Kantor. — On some partially-derived linear equations of the 

 second order, by M. Lucien Levy. — On the simultaneous effects 

 of rotatory force and of double refraction, by M. Gouy. The 

 author finds that these effects are in every respect conformable 

 to those resulting from the hypothesis of Airy, that they may be 

 completed by determining the values of K and S, and gene- 

 ralised by extending them to other mediums besides quartz. — 

 Action of boric acid on some coloured reagents, by M. A. Joly. — 

 On the hydrates of the sesquichloride of chromium, by M. L. 

 Godefroy. — On the alkaline feirocyanates and their combina- 

 tions with the chlorohydrate of ammoniac, by MM. A. Etard 

 and G. Bemont. — On a combination of acetic ether and the 

 chloride of calcium, by M. J. Allain-Le Canu. An analysis is 

 here given of this compi iund, which was fust indicated 1 >y Liebig. 

 — On three new compounds of iridium, yielded by the combina- 

 tion of the perchloride of iridium, IrCl 4 , with the hydrochlorates 

 of mono-, di-, and trimethylamine, and corresponding in their 

 composition to the chloro-iridate of ammoniac, by M. C. 

 Vincent. — On various haloid derivatives from substitutes of 

 propionic acid : chloruretted and ioduretted derivatives, by 

 M. I,. Henry. — On the significance of the polarimetric ex- 

 periments made with the solution of cotton in Schweizer's 

 liquid, by M. A. Bechamp. — On the influence of sunshine 

 on the vitality of the germs of microbes, by M. E. Duclaux. 

 From experiments marie with Tyrothrix scabtr, cultivated in 

 milk and Liebig's extract, the author finds that the light of the 

 sun is fifty times more destructive than its heat, and its hygienic 

 properties are thus fully confirmed. — Studies on the head and 

 mouth of the larva? of insects, by M. A. Barthelemy. — On some 

 points in the anatomy of the Cidarkte of the genus Dorocidaris, 

 by M. Prouho. — On a marine Hemiplera, sEpophilus Bonnarei, 

 Signaret, by M. R. Koehler. — On aveinous cirrhosi- determined 

 in the rabbit by Cysticercus pisiformis (Auct. ), and in connection 

 therewith on the embolic origin of certain gigantic cellules, by 

 M. Laulanie. — On a disease of the carob plant causing 

 hypertrophy of certain parts analogous to the so-called malady 

 of "la loupe" in the olive, by M. 1.. Savastano. — On the 

 actual value of the magnetic elements at the Observatory of the 

 Pare Saint-Maur, by M. Th. Mourceau. — On the earthquakes 

 that occurred in Andalusia on December 25, 18S4, and the 

 following weeks, by M. Macpherson, with remarks by M. 

 Daubree. — On the ascending movement observed in certain 

 waterspouts, by M. E. Vibert. 



Berlin 

 Meteorological Society, December 2, 1884. — Dr. Lcewen- 

 herz, after briefly sketching the history of the invention of the 

 thermometer and the early improvements made on it, showed a 

 large number of different constructions of the column and the 

 inclosure thermometer for meteorological purposes, comprising 

 the common as well as the maximum and minimum ther- 

 mometer, and, in concluding his address, discussed the produc- 

 tion of thermometers, the successive stages of which he illus- 

 trated by bringing forward glasses connected respectively witli 

 these. — Dr. Vettin spoke on the observations of clouds, and 

 described an apparatus for measuring their height. Suppose 

 the cloud projected to a distance of four miles, it then possessed 

 at that distance a "projected" speed, in its actual height it 

 possessed the actual speed, and from these two data the actual 

 height could be calculated according to the proportion ; the pro- 

 jected height H is to the actual height h as the projected speed 

 C is to the actual speed c. The actual speed was measured by 

 Dr. Vettin from the movement of the shadows of clouds, which 

 he could in most cases determine directly by means of the sharp 

 edges of the shadows cast on a large field of vision, where 

 the objects and their distance from each other were known 

 to him. In the case of cirrus clouds, again, the wandering 

 o 1 ill. darker and brighter spots along a street could mostly 

 be determined likewise with the help of a time piece. For the 

 purpose of determining the pr jected speed, Dr. Vettin made 

 use of a special apparatus, a longish camera obscura, containing 

 a lens which projected the image of the cloud on an inclined 

 mirror, which in turn reflected the image on a dim glass plate 

 at the side of the apparatus. This plate was round, and had 

 scratched into it at its periphery a circular division, at which 



the movement of the cloud-image from the centre towards the 

 periphery along a determined radius was measured. From the 

 observed time and the inclination of the apparatus witli the 

 help of tables calculated by Dr. Vettin, the projected speed could 

 readily be foun:!. Another method of measuring the height of 

 clouds consisted in determining the angle of the last ray after 

 sunset, or the first ray before sunrise, falling on a definite point of 

 the cloud formed with the horizon. Besides the tables referred 

 to in the first method described, Dr. Vettin had drawn up tables 

 for ascertaining this angle from the observed time and for calculat- 

 ing the height of the observed cloud-point. — In accordance with 

 earlier data adduced by Dr. Vettin, Prof. Boernstein showed two 

 experiments which brought into beautiful exhibition the process 

 by which ascending whirling currents of air were generated. A 

 glass plate, on which stood a high glass bell, was covered with 

 a layer of tol.acc j-smoke, which was heated from below by a 

 small flame applied near the centre. At once arose an upright 

 column of smoke, which broadened at the top and recurved 

 outwards and downwards so as to form a beautiful whirl. In 

 oiid experiment a closed glass case was set on a rotatory 

 apparatus capable of imparting to it a revolution such as the 

 earth possessed on the northern hemisphere, or the reverse. 

 The bottom of the glass case was warmed at a place of circum- 

 scribed area, from which arose a softly-ascending current of air 

 analogous to that of the fir t experiment. If the case were now 

 put in uniform rotation, and if, by means of a tube running 

 through the lid down to the bottom of the case, tcbacco-smoke 

 were blown into it, so soon as the smoke came in contact with 

 the heated place, a whirl was formed, and the smoke mounted 

 upwards in the shape of a spiral, which, under a rotation of the 

 ease similar to that of the northern hemisphere, was in a direc 

 tion opposed to the rotation of the hands of a clock. On the othei 

 hand, it the ease rotated in a manner corresponding with the 

 rotation of the southern hemisphere of the earth, the whirl of 

 tobacco-smoke and the ascending spiral rotated in the direction 

 of the hands of a clock. These simple and very instructive ex- 

 periments may easily be performed if too much smoke be not 

 admitted into the closed space and if the part heated at the 

 bottom of the case be restricted to little more than a mere point 



CONTENTS 



High-Level Meteorology .... 

 Our Book Shelf:— 



Day's " Exercises in Electrical and Magnetic Measure- 

 ment " 



Letters to the Editor ; — 



Earthquakes and Terrestrial Magnetism. — William 



Ellis . • 



Teaching Chemistry. — M. M. Pattison Muir . . 

 A Method of Isolating Blue Rays for Optical Work. 



H. G. Madan. (Illustrated) 



Barrenness of the Pampas. — Edwin Clark .... 



Japanese Magic Mirrors. — T. C. A 



Peculiar Ice-P'orms. — B. Woodd Smith : John D. 



Paul ... 



Iridescent Clouds. — Dr. H. Geelmuyden .... 

 Solar Phenomenon. — Dr. C. M. Ingleby .... 

 A Cannibal Snake. — Rev. Edward F. Taylor ; 



Rev. M. J. Bywater 



The Canadian Geological Survey. — Prof. T. G. 



Bonney, F.R.S 



Astronomical Phenomena for the Week 



Dust. By Prof. Oliver J. Lodge 



Hereditary Deafness. By Francis Galton, F.R.S. 

 Astronomical Telescopes for Photography, II. By 



A. Ainslie Common 



Some Experiments on Flame. By George J. Burch 



(Illustrated) 



A Line-Divider. (Illustrated) 



Universal Time and the Railways 



Notes 



Our Astronomical Column : — 



Comets of Short Period. (1) Encke's Comet . . . 



(2) Barnard's Comet 



(3) Wolf's Comet 



Geographical Notes 



Geology of Afghanistan 



University and Educational Intelligence 



Scientific Serials 



Societies and Academies 



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