688 



NATURE 



{Oct. 24, 1878 



— Researches in theoretical crystallography, by G. Uzielli.— On 

 the experimental determination of the electric density on the 

 surface of conducting bodies, by E. Beltrami. 



Reale Istituto Lombardo di Scienze e Lettere, Rendiconti, vol. xi. 

 fasc, xiv.-xv. — We note the following papers in this number : — 

 Colouring matters contained in the grape and a new means of 

 judging of the degree of ripeness of this fruit, by S. Pollacci.— 

 Transformation of hydroxylamine into nitrous acid, by Dr. 

 Bertoni. — Action of solar rays on haloid compounds of silver, 

 by Dr. Tommasi. — Reduction of chloral, by the same. — Results 

 of vivisection of the cerebellum, the transverse peduncles, the 

 semi-circular canals, and the nerves of taste, by Dr. Lussana. 



SOCIETIES AND ACADEMIES 



London 



Entomological Society, October 2.— H. W. Bates, F.L.S., 

 F.Z.S., vice-president, in the chair. — Mr. J. Lawrence Hamilton, 

 M.R.C.S., was elected a Subscriber, and Mr. Thos. Nottidge a 

 Member of the Society. — In reference to the statement of Mr. 

 F. Smith at the last meeting of the Society, to the effect that the 

 Linnean collection of insects contained in the apartments of the 

 Linnean Society had fallen into a state of complete neglect, Mr. 

 McLachlan read a report on the result of an examination he had 

 since made of that collection. Mr. McLachlan considered that 

 the collection was now in the same condition as it had been for 

 probably a quarter of a century, and that the charge of neglect 

 could not be sustained. Mr. S taint on fully corroborated this 

 view, and stated that from a recent examination of the lepidop- 

 terous portion of the collection he had been unable to detect any 

 appreciable deterioration in it since the year 1848, when he had 

 first occasion to consult it. — Mr. Jenner Weir exhibited specimens 

 of Hipparchia semele from various localities, showing a tendency to 

 vary in colour on the under side in accordance with the nature of 

 the soil of the district in which the specimens had been taken. — 

 Mr. McLachlan exhibited the eggs and young larvse of Ascalaphus 

 longicornis, found by M. E. L. Ragonot, in the Forest of Lardy, 

 apparently the northern limit of distribution of the species. Mr. 

 McLachlan also exhibited, on behalf of Mr. Edwin Birchall, an 

 example of Heliothts saitosa, captured by Mr. Campbell in the 

 north of Co. Donegal, Ireland. — Mr. Rutherford exhibited and 

 communicated a description of a new species of cetoniidse, from 

 M«unt Camaroons. Mr. Rutherford also exhibited a specimen 

 of Ranaleosoma ruspina, which was curiously and symmetrically 

 destitute of scales. — Mr. Champion exhibited specimens of 

 Amara infma, taken at Cobham, Surrey. — Mr. Forbes exhi- 

 bited a collection of insects from Switzerland. — Mr. Wood 

 Mason read a note on a saltatorial Mantis, and exhibited a speci- 

 men of the insect which had been captured on the banks of the 

 Tagus. He also read notes on the hatching period of Mantidse 

 in Eastern Bengal, and on the presence of stridulating apparatus 

 in certain Maniidce. Mr. Wood Mason also stated that he had 

 discovered a remarkable case of viviparity in an orthopterous 

 insect, Pancsthia javanica, a cockroach inhabiting the tropical 

 forests of Southern Asia and Australia. 



Paris 

 Academy of Sciences, October 14. — M. Fizeau in the 

 chair. — The President announced the death of M. Delafosse, 

 member in the Section of Mineralogy. — The following papers 

 were read : — Presentation of vol. ix. of the " Observations of 

 Pulkowa," by M. Otto Stnive. This contains micrometric 

 observations made by the author during forty years (with the 

 same instrument and by the same method) on double and mul- 

 tiple stars. They continue the series of twelve years' like 

 observations by his father at Dorpat. By these measurements 

 M. Struve has been able to observe, e.g., the epicycle idal 

 motions of the third star in f Cancri, to determine approxi- 

 mately the orbit of 42 Coma: Ber.,and clear up the controverted 

 system of 61 Cygni. The measurements in this volume relate 

 chiefly to double stars of the Dorpat catalogue, in the northern 

 he iiisphere, and to all systems discovered at Pulkowa. Another 

 volume will contain extended observations. — Formulee relating to 

 perforation of iron armour plates, by M. Martin de Brettes. — 

 M. Decharme presented a supplement to his memoir on vibratory 

 forms of solid or liquid bodies ; it relates to experiments with a 

 large glass plate, with which the former results (with small 

 plates) were confirmed. — M. Cham pin communicated an ob- 

 servation regarding transformation of aptei'ous into winged 



phylloxera in the galls. — Third letter of Prof. Watson on the 

 discovery of intra Mercurial planets. M. Mouchez considered 

 the information here given answered his objections in great part, 

 and left no doubt of the reality of the discovery of at least one 

 of the two planets. — Reply to a communication by Herr Weber 

 on thermodynamics, by M. Levy. — On a new micrometer, meant 

 especially for meteoi-ological researches, by M. Govi. In this 

 the threads or fine wires are replaced by the two edges of a slit 

 made in a very thin layer of silver, gold, platmum, or other in- 

 alterable metal, placed on the surface of a plate of glass having 

 perfectly plane and parallel faces. The slit is produced 

 by means of a light metallic tracer; and for larger slits 

 the tracer is made to remove the metal in advancing parallel 

 lines. Advantages attach to the extreme thinness of the 

 metallic layer, its opacity, rigidity, and inalterability under con- 

 siderable thermometric and hygrometric changes, the possibility 

 of easily making slits as narrow or as wide as may be desired, 

 and the facility of substituting different plates for each other in 

 the same frame. — On a new metal, philippiwn, by M. Dela- 

 fontaine. It is so called in honour of M. Philippe Plan- 

 tamour, of Geneva, the friend and pupil of Berzelius. The 

 author's, former conclusions are confirmed ; the new earth 

 (of samarskite), which has a colour and a molecular 

 weight intermediate between those of yttria and terbine, is 

 not a mixture of these two bodies, but an oxide of a 

 new metal. Supposing provisionally that Philippine is a 

 protoxide, its approximate equivalent^ is between 90 and 

 95. M. Delafontaine gives the properties of some com- 

 pounds, the philippic formiate, sulphate, nitrate, &c., and 

 describes the spectroscopic appearances gievn by concen- 

 trated solutions of philippium. These present a very broad 

 characteristic absoption band which is absent from terbic, 

 yttric, and erbic solutions. — Action of the juice of beet-leaves 

 on perchloride of iron, under the influence of light, by M. 

 Pellet. It has, in absence of chlorophyll, the power of re- 

 ducing salts of iron easily, in light. This reduction may take 

 place in the dry state, and with solutions having no longer 

 vitality. It is due to oxidation of f:everal organic substances 

 contained in the leaves, such as sugars, tannin, azotised matter, 

 &c. — M. Ronder presented a note on an arrangement for ob- 

 serving the stars in broad daylight, without the aid of a telescope ; 

 it consists in the use of a long tube, the lower end of which ter- 

 minates in a dark chamber. 



CONTENTS Pagb 



The Conshrvation of Rivers 66i 



Stellar Ohjects seen during the Eclipse of 1869. By J. R. 



Hind, F.R.S f63 



Lake Dwellings £64 



Our Book Shelf :— 



" Annual Record of Science and Industry for 1877 " fe? 



Whitworth's " Choice and Chance " 665 



Magnus' " Hydrostatics and Pneumatics " (,t(> 



Brown's " Pine Plantations on the Sand-Wastes of France " . . eCo 



Caruel's " Vegetable Morphology " 667 



Letters to the Editor :— 



American Exploration. — Capt. W. A. Jones 667 



Geological Climate and Geological Time. — Prof. Joseph le 



CONTE 668 



The Magnetic Storm of May 14, 1878.— W. H. Preece .... 668 



Giddiness. — F. G 669 



Our Astronomical Column :— 



The Saturnian Satellite, Hyperion (:(>-) 



The Mean Parallax of a Star of First Magnitude 669 



0.\ THE Tides of the Southern Hemisphere and of the Medi- 

 terranean. By Capt. Evans, R.N., F.R.S., and Sir William 



Thomson, LL.D., F.R.S 670 



The Physical Functions of Leaves (JVith Illustrations') .... 672 



Edison's Inventions {With Illustrations') 674 



Colour Blindness in Relation to the Homeric Expressions 



for Colour. By Dr. W. Pole, F.R.SS. L. and E 67S 



Chemical Notes : — 



Ti^stimation of Mercury . . . _. 679 



Separation of Antimony and Arsenic 679 



.Specific Heats of Mercury and Iron 679 



Latent Heat of Water at Temperatures below 0° C 679 



Preparation of Salts of Nitrous Oxide £79 



On Manganese Tetrachloride (MnCU) .......... 679 



Spontaneous Ignition of Hydrogen by Finely-divided Zinc . . . 679 



Meteorological NotesJ 6£o 



Geoora»hicai. Notes 6S0 



Notes .... 681 



On a New Method of Studying the Optical Characters of 



Minerals. By H. C. Sorby, F.R.S., Pres. G.S., &c 684 



Recent Observ.\tions upon the Placentation of the Sloths. 



By J. C. Galton f>£6 



University and Educational Inteiligencb ^87 



Scientific Serials ^ 87 



Societies and Academies ^^3 



