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term R was such that CPR represented the whole waste loss inness in the surrounding rocks; and that portion of it which the conductor, whilst a included everything wasted outside the contained the highest percentage of potash finally consolidated conductor.- A paper on the vi-cosity of liquids, by Prof. J. | as pegmatite. Special attention is directed to the distribution Perry, F.R.S., assisted by J. Graham and Ć. W. Heath, was of pegmatite. This rock is widely distributed in the Southern read by Prof. Perry. The viscosity was tested by suspending Highlands, and cuts across every known system of folding. It a hollow cylinder within an annular trough containing the is consequently newer than any member of the metamorphic liquid, and measuring the torque exerted on the cylinder when series. The surrounding metamorphic schists are next dealt the trough rotated at various speeds about its axis. In the with. These are remarkable for their highly crystalline conpaper the equation of motion under the conditions of the ex dition, and also on account of the presence of many minerals periment is discussed, the error introduced by assuming that known to occur in regions where thermo-metamorphism has the liquid moves in plane layers being shown to be about 0.5 taken place. The characters of the more important minerals per cent. By measuring the viscous torques exerted with dif. are described in detail. The rocks of the metamphoric area ferent depths of liquid in the trough, the correction for the edge become less and less crystalline as they are followed towards the of the suspended cylinder was found to be o 8 c.m. On plot Highland border. Three zones, characterised respectively by ting the results obtained with sperm oil at different temperatures the ininerals sillimanite, cyanite, and staurolite, have been and constant speed, a discontinuity was noticed about 40°. roughly mapped. The more important rocks found in these For a speed of nine revolutions a minute the viscosity (u) could zones are described in detail, and evidence is given to show that le very approximately calculated from the formula u = 2:06 the boundaries between the zones do not in all cases coincide (0 - 4 2)*656 below 40° C. and u = 21.67 (0 – 4:2) -1°349 above with the strike of the rocks. Thus, a thin bed of quartzite, 40°C., o being the temperature. Experiments on the change which retains its character in consequence of the simplicity of of density of sperm oil with temperature, made by Mr. J. B. its chemical composition, may be followed through all the Knight, indicated a minimum density about 40°. Subsequent | zones; whereas the bed adjacent to it is in the outer zone a experiments with other samples had not confirmed these ob staurolite-schist, in the intermediate zone a cyanite-gneiss, and servations. The paper contains several tables of the results near the contact with the igneous rock a coarse sillimanite-gneiss. obtained in various experiments. Those performed at constant Evidence is given to show that the original rocks formed a sedi. temperatures show that sor slow speeds the torque is strictly mentary series. The phenomena are compared with those of proportional to speed, but afterwards increases more rapidly, other areas where thermo-metamorphism has taken place ; and probably owing to the critical speed having been exceeded. the conclusion is reached that the differences are of degree rather After concluding the paper Prof. Perry read a letter he had than of kind. The special features of the area in question are received from Prof. Osborne Reynolds on the subject, who attributed to the depth at which the change was produced. The doubted whether the true critical velocities had been reached paper is illustrated by a map of the district and a table of original in the experiments. In the particular arrangement employed, analyses. This paper gave rise to a discussion, in which the he would expect no critical velocity in the outer ring of liquid, president, Prof. Judd, Mr. Rutley, General McMahon, Dr. whilst in the inner ring the motion would be unstable from the Hicks, Mr. Marr, Dr. Du Riche Preller, Mr. Teall, and the first. Mr. Rogers pointed out that experiments which corro author took part. borated those of Prof. Perry had been made by M, Couette and published in Ann. de Chim. et de Phys. [6] xxi.

Zoological Society, March 28.-Sir W. H. Flower, Geological Society, March 22.-W. H. Hudleston, F.R.S.,

K.C.B., LL.D., F.R.S., President, in the chair. -A report

was read, drawn up by Mr. A. Thomson, the Society's head. President, in the chair.— The following communications were

keeper, on the insects bred in the insect-house during the past read :-On the jaw of a new carnivorous dinosaur from the

season.-A communication was read from Mr. Herbert Druce, Oxford clay of Peterborough, by R. Lydekker. The author

giving an account of some new species of Lepidoptera Heterocera, describes a fragment of the left side of a lower jaw of a carni

chiefly from Central and South America. -Mr. F. E. Beddard, vorous dinosaur from the Oxford clay of Peterborough, in

F.R.S., read a paper on the brain of the African elephant. The dicating a new genus and species, which he names Sarcolestes

author gave reasons for disagreeing with some of the conclusions Leedsi. Some remarks were made on this paper by the Presi.

of Dr. Krueg, but confirmed others. The outline is more like dent and Prof. Seeley.-On a mammalian incisor from the Wealden of Hastings, by R. Lydekker.

that of the carnivorous than the ungulate brain, but the principal

In this paper a small rodent-like tooth from the Wealden of Hastings, belonging to

furrows appear to be arranged on a plan characteristic of the

elephantidæ. -Mr. W. T. Blanford showed that the various Sir John Evans, K.C.B., is described. It is probably the front

names hitherto employed in systematic works for the bird called tooth of one of the mammalian genera found in the Purbeck

by Jerdon the Himalayan cuckoo (Cuculus himalayanus, Beds, as may be gathered from American specimens. The read.

C. siriatus, and C. intermedius) belonged to other species. He ing of this paper was followed by a discussion, in which the President, Sir John Evans, Mr. C. Dawson, Mr. Oldfield

also gave reasons for not adopting S. Müller's C. canoroides,

and accepted the term C. saturatus, Hodgson, as the correct Thomas, Dr. Forsyth-Major, Dr. H. Woodward, and the author

scientific name. -A communication was read from Mr. F. M. took part.-On an intrusion of Muscovite-biotite-gneiss in the

Woodward, entitled “Further observations on the genitalia of south-eastern Highlands, and its accompanying thermo-metamor.

British earthworms." This paper chiefly dealt with supplephism, by George Barrow, of the Geological Survey. (Com.

mentary gonads which were found to be much more common municated by permission of the Director-General of the

than had been supposed ; in one specimen an hermaphrodite Geological Survey.) The area to which this paper refers lies in the north-eastern part of Forfarshire, and is drained by the

gland was discovered in addition to testes and ovaries. two Esks. The author first describes the distribution, mode of Entomological Society, March 29.—Henry John Elwes, occurrence, and petrological characters of the intrusive masses. President, in the chair. -Mr. G. C. Champion exhibited a living In the north-western portion of the area the intrusive rock is specimen of a luminous species of Pyrophorus, which had been always a gneiss, and occurs in thin tongues which permeate the found in an orchid house in Dorking. It was supposed to have surrounding rocks. Towards the south-east these tongues emerged from the roots of a species of Callleya from Colombia. amalgamate and form large masses, in which the soliation is - Mr. A. H. Jones exhibited living full-grown larvæ of less marked. Moreover, in this direction the large masses are Charaxes jasius, found by Mr. Frederic Raine, at Hyères, often fringed with pegmatite, especially on their southern and feeding on Arbutus unedo.-Surgeon-Captain Manders exhi. eastern edges. Where the rock is a gneiss, it is composed of bited a series of Lycana theophrastus (rom Rawal Pindi, showoligoclase, muscovite, biotite, and quartz, but contains no ing climatal variations, the rainy-season form being of darker microcline. As the gneissose character becomes less marked, coloration, and larger than that occurring in the dry season. the oligoclase diminishes in amount, and microcline begins to The ground colour of the former on the under surface was appear, especially towards the margins of the masses. In the markedly white with deep black striæ ; in the latter form the most south-easterly of these microeline is greatly in excess of ground colour was distinctly reddish, and the marking reduced oligoclase. The differences in structure and composition of these to reddish lines. He said that the latter form had been de. masses are believed by the author to be due to the straining off scribed as L, alteralus.-Mr. S. G. C. Russell exhibited a beau. of the crystals of earlier consolidation during intrusion under tisul variety of Argynnis selene, taken near Fleet, Hants ; two great pressure. The still liquid potash-bearing portion of the varieties of A. selene from Abbot's Wood, Sussex ; typical magma was squeezed out and forced into every plane of weak specimens of A, selene and A. euphrosyne for comparison ; and a remarkable variety of Pieris napi from Woking.-Mr. C. J. | touching each other, and arranged in a line nearly east and Gahan exhibited a microscopic preparation of the antenna of west, forming a very regular street. At the end was a sort of the larva of a beetle (Pterostichus), for the purpose of demon square enclosure of stone, measuring about 2'5 by 3 m., with a strating the sensory nature of the so-called “appendix " of the door towards the south. Inside it presented a circular cavity, antenna. Since he wrote a note describing this structure, a 30 cm. in dianieter and 20 cm. deep, which still appeared to short time ago, he found that Prof. Beauregard had already contain ashes, and whose clay walls were baked to a depth of suggested its sensory character, and was inclined to believe that about 4 cm. Similar hearths have been found among the Kabyles it was an auditory organ.-Mr. H. Goss exhibited a specimen of Algiers. Near this structure was another, of circular form, of Trogus lapidator, Grav., believed to have been bred from a built of rough blocks of limestone and sandstone, with a fri. larva of Papilio machaon, laken in Norsolk by Major-General angular door built of two enormous blocks of sandstone, joining Carden. Mr. Goss stated that he sent the specimen to the at the top, and leaving a space of 50 cm. at the bottom, This Rev. T. A. Marshall, who said it was a well-known parasite of hut also showed traces of cooking operations. A little farther P. machaon on the Continent, but not proved to exist in the on came a series of seven similar huis, followed by two larger United Kingdom.-Mr. F. Merrifield said he knew this para. | ones without hearths, and finally two more like the first. The site, and had bred several specimens of it from pupæ of total length of the village was 114 m. All the masonry consisted P. machaon received from Spain. ---Colonel Swinhoe read a of blocks of limestone or sandstone, cemented with clay. A paper, entitled “The Lepidopiera of the Khasia Hills. Part I.” | large number of stone and Aint implements was found, including A long and interesting discussion ensued, in which Mr. Elwes, half a dozen sandstone hatchets, polished or prepared for Mr. Hampson, Colonel Swinhoe and others took part.- Mr. | polishing. The village is, curiously enough, situated at the very W. Bartlett-Calvert communicated a paper entitled “New bottom of the valley. Chilian Lepidoptera.”—Mr. J. W. Shipp communicated a paper entitled “On a New Species of the Genus Phalacro. gnathus."


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cal Treatise on Bridge Construction, 2 vols.: T. C. Fidler (Griffin). - The the Roumanian frontier, to that of Astrakhan, on the Lower

Steam-Engine, 2 vols : D. K. Clark (Blackie). Volga, the difference of longitude being 19° 11' 55":11. The PAMPHLETS.-Sulla Distribuzione del Potenziale Nell'Aria Rarefatta per measurements gave 1,446,462 m. for the length of the arc, or corsa dalla Corrente Elettrica: Prof. A. Righi (Bologna).-The Funda.

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(Boston). The Imaginary of Algebra : Prof. A. Macfarlane (Salem) everywhere attained. Between Rostov-on-the-Don and Sarepta Australian Museum. Sydney: Catalogue of Australian Mammals, see. the geodetic arc exceeds the astronomical one by 15"-26, whilst (Sydney).-Catalogue of the Michigan Mining School Houghton, between Sarepta and Astrakhan the astronomical arc is the Michigan, 1891-92 (Houghton). larger by 9":82. This deviation shows a remarkable agreement with that obtained in the measurenient of the 52nd parallel and indicates that the plains of Eastern Russia are

CONTENTS. formed according to the same geometrical law over a vast area.

The Planet Mars. By William J. S. Lockyer . . . 553 A comparison of the resulis for the two arcs, with reference to the

Magnetic Observations in the North Sea ..... 555 length of the meridian measured from the North Cape to Dorpat Manual of Dairy Work. By Walter Thorp .... 555 and the Lower Danube, indicates a polar depression of 1 in 299:65, Our Book Shelf:which agrees closely with that found by Bessel for Germany in Moitelay : “ William Gilbert of Colchester, Physician 1841 (1 in 299-26), but differs from that of Clarke (1 in 293-46). —

of London, on the Loadstone and Magnetic Bodies, Condensation experiments of the acetylcyanacetic acids with the

and on the Great Magnet the Earth. A New phenols, by M. A. Held.-Synthesis of erythrite, by M. G. Physiology, Demonstraied with many Arguments Griner.-Action of temperature upon the rotatory power of and Experiments" ...... liquids, by M. A. Aignan. Reasoning from the fact that the Somerville: "Report on Manurial Trials.”_W. T. oxide of isobutylamyl presents a rotatory power which changes

Laurie : “The Food of Plants” .......... its sign at -30°, M. Colson has concluded that “ chemical Letters to the Editor :constitution does not appear to be the preponderating factor in Fossil Floras and Climate.—Sir William Dawson, the value or the sign of the rotatory power." But the fact

F.R.S. . . .
sidir: vino::::::::

. . referred to can be explained as the effect of the mixture of a Notes on a Spider.-H. H. J. Bell. ... negative and a positive rotating substance respectively. A Origin of Lake Basins.-J. C. Hawkshaw mixture of essence of terebenthine (left-handed) and camphor | The Musk-Ox. (Ilustrated.).. (right-handed) was dissolved in benzene, and observed through | On the Carburisation of Iron. II. By John P the 20 cm. tube of the polarimeter in different kinds of light. | Notes .... This mixture changed from negative to positive at a temperature Our Astronomical Column:between 61° and 73°C. for red light, between 13° and 33° C. for Solar Observations at Rome ......... yellow light, and was positive for all the temperatures for green Parallaxes of u and 0 Cassiopeia .... ... light, the angle of rotation being 2° 24' at 13°, and 6° 43' at Fall of a Meteorite .... 90° C. To explain M. Colson's observation, it is not even Jahrbuch der Astronomie und Geophysik . necessary to assume that the oxide contains two substances of The Observatory ......... rotatory powers of different signs. It suffices to admit, as has Geographical Notes .. been done in the case of solutions of tartaric acid, that the The amide and Imide of Sulphuric Acid. By A. E. molecules of isobutylamyl are susceptible of polymerisation in Tutton.... the liquid state, so that the sign of the rotatory power character. The Densities of the Principal Gases. (With Dic: ising the molecule of the substance is that observed at the higher grams.) By Lord Rayleigh, F.R.S. temperatures.-Neolithic village of the Roche-au-Diable, near Electrical Railways. By Dr. Edward Hopkinson. Tesnières, canton of Lorez-le-Bocage (Seine-et-Marne), by M. Hail Storms. By H, C. Russell, F.R.S. (Mustrared.) Armand Viré. In the course of excavations in the valley of Scientific Serial ................. Lunain a village was discovered of a type not met with up to Societies and Academies . now. It consists of a series of ground-works of square huts / Books and Pamphlets Received .........,


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