This basin consists of the two haunch bones which meet together in front, but behind are separated by the lower part of the backbone (called the sacrum), to which the haunch bones are attached, and which forms the hinder portion of the pelvis. The pelvis has a depression, or socket," on each side, into which fits the head of one of the thigh bones. Each "haunch bone" consists of three parts, which are, in man, primitively distinct, but afterwards anchylose together, and all three elements (in each haunch bone) take a share in the formation of the bony thigh-socket, or acetabulum. These three elements are named—1, ilium; 2, ischiam; and 3, pubis. It is the ilium which is adjoined to the sacrum. The pubis, in man, meets its fellow of the opposite side in the middle line in the front of the body. The two ischia (one to each haunch bone) support man's body when in a sitting pos

ture.

The pelvis of man is often quoted as one of the most peculiar and characteristic parts of his skeleton, and its shape in him is very peculiar. Nevertheless the pelvis as it exists in frogs and toads is a far more exceptional structure. It is so in the extraordinary elongation, yet small vertebral attachment, of the haunch bones ilia, as also in the fact that these bones as well as the other pelvic elements (ischia and pubes) are all closely applied to each other in the middle líne of the body. Thus these elements form a bony disc, and the two sockets (acetabula) destined, respectively, for the heads of the two thigh bones, come to be closely approximated one against the other. The great elongation and small attachments of the ilia allow the pelvis as a whole to be bent upon the backbone. Thus the hinder part of the body is moveable and forms as it were an additional common root segment for the two limbs. ST. GEORGE MIVART

(To be continued.)

SOUNDINGS IN THE NORTH PACIFIC Ο VER a year ago the United States Congress authorised preliminary measures for laying a submarine cable from the west coast of America to Japan. The United States steamer Tuscarora, then on duty off the Isthmus of Darien, was despatched on this business, and started September 22, 1873, from San Francisco for the Straits of Juan de Fuca. Reconnaissances off Victoria, Vancouver's Island, discovered a gradually shelving bottom in all respects suitable for a cable landing. The steamer coaled at Nanaimo. Coal is also found at Newcastle Island, which is not far distant. It may be mentioned that the coal of this region is semi-bituminous, and that recent discoveries have largely increased its product.

The line of soundings extended along a great circle drawn from Cape Flattery to Oonalaska Island. At lat. 53° 58' N., long. 153° W., within about 400 miles of Oonalaska, the coal was exhausted, and the vessel returned to Victoria. The ocean bed sank rapidly from Cape Flattery to lat. 48° 54′ N., long. 126° 21′ W., then rapidly and steadily to lat. 49° 26' N., long. 128° 37' W., then more rapidly to lat. 49° 46' N., long. 129° 27′ W., at which point the depression was 1,452 fathoms. Thence a peak rose in the sea bottom, with a summit at 1,007 fathoms depth, in lat 51° 40′ N. long, 137° 32′ W. Its rise was fully as rapid as the depression preceding it, and the depression beyond it, the side being equally steep, was somewhat greater. The slope after the western bottom of this submarine mountain was reached was exceedingly gradual, and somewhat undulating. Perhaps the following estimates, roughly made from a sketch, will give a clearer notion of the ground surveyed. At about 100 miles from Cape Flattery, depth about 400 fathoms ; at 150 miles, 1,000 fathoms; 170 miles, 1,400 fathoms; 200 miles, 1,0co fathoms; 300 miles, 1,600 fathoms; 400,

1,900 fathoms ; 500, 2,000 fathoms; 600, 2,000 fathoms ; 700, 2,100 fathoms; 800, 2,200 fathoms; 900, 2,300 fathoms; 1,000, 2,300 fathoms; 1,100, 2,50c fathoms.

During soundings on the return voyage to San Francisco, another submarine mountain was discovered in lat. 41° 30' N., long. 127° 11′ W., the depth at its summit, which the sounding instruments showed to be of a rocky character, being only 996 fathoms. Around it, at distances of 20 miles, the depth was between 1,600 and 1,700 fathoms.

The water temperatures along the line of soundings for the cable, at depths of over 1,000 fathoms, varied from o° 45′ C. to 2° 43' C.; surface, 10° 35′ C. to 14° 15' C. In lat. 53° 58′ N., long. 153° 00′ W., the increase from 50 fathoms to surface, was gradual; but at 50, 100 and 200 fathoms the same temperature was found as at 2,500 fathoms.

The conclusion has been reached in the course of a series of observations made during the return voyage, and subsequently, that what is known as the "California coast current," is really a warm, and not as hitherto supposed, a cold stream. The observations determined the existence of a warm current, presumably a continuation of the "Great Japanese Circle Current," setting toward the south and east, of a surface temperature averaging 15° C., between the positions lat. 48° 36' N., long. 126° 36′ W., and lat. 50° 34' N., long. 131° 38′ W. Outside of this current the temperature was but 10° C. Its width, between what is known as "Fleurier's Whirlpool" and the coast of California, is about 700 miles; its depth in lat. 44° 54' N., long. 125° 13′ W. is about 200 ft.; its speed, one to two knots per hour. Under-currents below this stream have been determined, setting to the north and west. The counter-current does not appear to extend more than 30 to 35 miles from shore, moving at a half to one knot per hour, with a depth of 200 to 300 fathoms.

The expedition was equipped with a great variety of sounding apparatus, of which only a few instruments gave perfect satisfaction, and several proved quite useless. The vessel carried 32,000 fathoms line, of which 21,000 were 1 in., carbonised. Among the satisfactory instruments, Prof. Thomson's is mentioned. This is worked by hand, winding No. 22 piano wire, capable of resisting a strain of 200 pounds. It has a registering indicator and a dynamometer attached. For bringing up material from the bottom, Belknap's cylinder, No. 2, gave the best results, the lower half of the cylinder being usually filled with about three ounces of sea-bottom material, and the upper half with water that had rested on the sea-bottom. The material is brought up secured in the case of a

Sand's cup" by a cylindrical sleeve. The latter is held by a spiral spring, in a position just covering a small orifice in the hollow cylindrical case. On striking bottom, the sleeve is forced up, permitting the material of the ocean bottom to enter the orifice. The instrument is driven into the bottom material by a weight which carries it down with great velocity. This weight, consisting of two hemispheres of iron attached just above the spring, is automatically detached when bottom is struck, by the slackening of the line. Upon drawing up the line, the spiral spring again forces the sleeve down, covering the orifice. The material drawn from the greatest depths was the usual chalky, pasty mud, smooth and homogeneous, rarely containing sand, chiefly composed of casings of diatoms and foraminifers, with here and there the spicule and siliceous skeletons of the smaller sponges and polycystina.

Although the expedition met for the most part with unsettled and unfavourable weather which interfered with its work, that which it has accomplished is regarded as eminently satisfactory. There is little doubt but that the route upon which the soundings have been made, will be the one selected for the cable; and next spring the work will be extended from the point at which it was discontinued.

NOTES

To the large number of his paleontological discoveries Prof. Owen has quite recently added that of a most peculiar bird from the London clay of Sheppey, which he has named Odontobteryx toliapica. This new form, known only from the skull, though perfectly ornithic in general structure, and exhibiting many of the characters of the Steganopodes (Gannets and Cormorants), presents a peculiarity not found in any existing bird. The trenchant margins of the bones of both jaws, instead of being simple, are provided with long conical bony processes, like the serrations in a coarse saw. The posterior of these serrations, which are alone preserved, are directed somewhat forwards; the anterior were probably less inclined, or even directed backwards like the homologous horny processes in the Goosander. The theoretical importance of this new form is great; for it is as good an example as can be brought forward of the loss in modern times, from a persistent type of animals, of a well-developed specialised structure. Many who criticise the evolution hypothesis appear to assume that progress, or what is the same thing, development in the individual of a maximum number of specialised organs, is an indispensable element of the Darwinian hypothesis. Such, however, is certainly not the case after a certain degree of elaboration has been reached. For, taking Odontopteryx as an example, it is evident that though this bird had in the struggle for existence acquired a dentigerous mouth, in which point it was in advance of all other members of the bird type, nevertheless its being thus able to obtain food which others could not hold, did not render it in the least less liable to be exterminated by many of the other accidents associated with existence.

The upheaval of the sea-bottom, for instance,

in its accustomed haunts, would have been destructive to it as to any other of its kind, and probably more so; for the specialisation of the jaws is certain to have been attended with a similar modification in the limbs, resulting in the loss of the power of flight, which would not allow of its removing to a new locality on the change in the physical geography of its home. So with the equally modified Moa, Dodo and Auk, the term of existence of the Odontopteryx was a short one, because the tendency of its development was too much towards a degree of uniformity in surrounding circumstances, which the human mind alone knows is not justified by facts.

THE autumn show of the larger fungi at the Royal Horticultural Society has so steadily increased in interest and popularity, that it is intended to considerably extend it next year (1874). The following extract from the recently issued official schedule states the classes which are admissible, and the number and value of the prizes, which are entirely open to all competitors :Wednesday, Oct. 7.--Class 1, Collection of Fungi, arranged according to their botanical affinities. Neat arrangement and correct nomenclature will be taken into account in awarding the prizes. The edible and poisonous species are to be so marked on their respective labels; the edible species being named on white labels, the poisonous on red ditto, the rest on yellow ditto. Prizes: 57, 3, 21. Class 2, Collection of Edible Fungi. These should be shown, when possible, in juxtaposition with specimens of similar but noxious species. Prizes: 31., 2., Il. Class 3, Collection of New or Rare Fungi. Prizes: 31., 2., 17. Class 4, Cultivated Edible Fungi. This class is intended for species likely to be useful as esculents, but which are not now known in the cultivated state. Prizes: 31., 2., Il.

THE following has been announced as the Cambridge Natural Science Tripos:-First Class.-Martin, Christ's; Balfour, Trinity; (a) Bettany, Caius; (a) Hartog, Trinity; (a) Sollas, John's; Koch, John's-those marked (a) being equal in merit. Second Class. (a) Balderston, Caius; (a) Davies, John's;

(a) Jukes-Browne, John's; (a) Ogilvie, Trinity; (a) Salomons, Caius; Coe, Sidney; Ds. Fletcher, St. Peter's; Ds. Myers, Trinity: Symons, Trinity; Ds. Vinter, Caius; Ds. Yonge, Trinity Hall, the last six equal in merit as well as the first five Third Class.-Ds. Hawker, Trinity; Lighton, Trinity, equal. The undermentioned acquitted themselves so as to deserve an ordinary degree :-Crallen, Emmanuel; Mogg, Pembroke ; Slater, St. Catharine's.

MR. ROBERT E. BAYNES, B.A., Wadham College, has been elected to a Lee's Readership in Physics at Christ Church, Oxford. Mr. Baynes gained a First-Class in Mathematical Moderations in Trinity Term 1871; and a First-Class in the School of Natural Science, Michaelmas Term 1872. The stipend of the Lee's Reader is 300/. per annum for the first four years after election, 400/. for the next three years, and 500l. after seventh year from election. He has also a right to occupy rooms in college rent free.

AMONG the more important of the numerous current publications of the United States Hydrographical Office, under Com"Coast Pilot" of the modore Wyman, is the first volume of a coast of Brazil, prepared by Lieutenant Gorringe, and covering the region from Cape Orange to Rio Janeiro, forming a volume of nearly 400 pages, in which the peculiarities of that portion of the coast are detailed with great minuteness, and accompanied by numerous profile sketches of the shores as observable from the vessel at sea. Another report of a very practical bearing is the result of the observations made by the United States steamer Narraganset during a cruise between Honolulu and Sidney, conducted between July 6 and September 7, 1872. The points visited were Christmas Island, the Gilbert group, Mulgrave Islands, the Disappointment and Duff Islands, and the Vanikoro Islands.

THE Council of the Society of Arts have given notice of their intention to provide a short course of lectures suitable for a juvenile auditory during the Christmas holidays. For this purpose arrangements have been made with Mr. Frank Buckland, M.A., Her Majesty's Iespector of Salmon Fisheries, to deliver two lectures "On the Structure and Habits of Beasts, Birds, and Fishes, as showing Beauty and Design," on Friday, January 2, and Friday, January 9, at 8 P.M. The lectures will be illustrated by specimens. It is intended to make every effort to obtain an entirely juvenile audience, and the notice in the Society's Journal impresses strongly upon the members the fact that only children, not adults, are wanted. The plan is, as far as the Society of Arts is concerned, quite a new one; though the Royal Institution have before now had courses of juvenile lectures.

Taylor, F.G.S., F.L.S., at Ipswich, on WE are glad to hear that the course of lectures by Mr. J. E. "Physical Geography and Geology," has been so successful that the place of meeting has had to be changed to a larger building. The average attendance, we believe, has been 500.

"THE Fifth Annual Report of the Trustees of the Peabody Academy of Science for the year 1872" (Salem, U.S.) is a very cheerful one. The collections in the museum of the Academy are mainly in Natural History and Archeology, and to both departments very large additions were made during the year 1872; the museum, indeed, promises to become one of the most valuable collections in the United States. By the indefatigable researches of Dr. C. C. Abbott a collection of 3,000 implements of the stone age has been brought together, all obtained from the immediate vicinity of Trenton, N.J., on the banks of the Delaware and adjoining fields and hills. The greater part of the present Report is occupied by a number of papers by Mr. A. S. Packard, jun., the Curator of the Articulates. These papers are:"Synopsis of the Thysanura of the Essex County, Mass., with

descriptions of a few extralimital forms," "Descriptions of New American Phalanidæ," "Notes on North American Moths of the Families Phalænidæ and Pyralidæ in the British Museum," "On the Cave Fauna of Indiana," and "Record of American Entomology for 1872."

THE Dundee Advertiser is a daily paper of wide circulation and of considerable influence in the north, and is, therefore, we presume, able to keep a competent "London Correspondent." That gentleman, however, in writing in a recent number of the Advertiser about Mr. Prestwich's paper on tunnelling the Channel, is made to make the extraordinary statement that "in order to get under the chalk to the Palæogovic rocks the Company would have to go to a depth of ten miles on either side!" We had recently occasion to point out that science is at a discount in Dundee.

THE Bordeaux district branch of the French Association for the Promotion of Science has resolved to hold its meetings weekly on Mondays.

GOVERNMENT has sanctioned the appointment of a Professor of Physical Science at the Madras Presidency College, on a salary of 500 rs., rising to 700 rs. per month.

THE New York papers have lately contained quite a number of articles urging the propriety of establishing an Aquarium in Central Park, on the same scale as that at Brighton.

WE learn from La Revue Scientifique that two specimens of the Ibis, a bird found only in Egypt and at the mouths of the Danube, were recently shot by a hunter in the department of the Somme.

WE can only briefly refer to the following new books and new editions "Where there's a Will there's a Way; or, Science in the Cottage" (Hardwicke), is the title of a little volume by Mr. James Cash, containing an interesting collection of lives of persons in humble life who have to some purpose pursued the study of science, especially of Natural History.-" Mountain, Meadow, and Mere, a series of Outdoor Sketches of Sport, Scenery, Adventures, and Natural History," by Mr. G. C. Davies

(Henry S. King & Co.), is a series of articles which originally appeared in the Field and some magazines. The sketches are generally graphic and racy, and contain information that, we should think, would be valuable to sportsmen of various kinds, with occasional observations on the natural history of the districts referred to by the author.--Mr. John Murray has just published third editions of Mr. H. W. Bates' "Naturalist on the River Amazons," and Mr. J. G. Bertram's interesting work, "The Harvest of the Sea, including Sketches of Fisheries and Fisher

Folk." The latter work, which has been the means of doing good service to our fisheries, has been revised, and a considerable amount of new matter added.

A Times telegram dated Rome, Dec. 20, states that Colonel Gordon, who has accepted from the Khédive the leadership of a scientific expedition into Upper Egypt, is furnished by his Highness with a credit of 100,000l.

WE are glad to hear that a Section for Microscopical Investigation has been formed in connection with the Leeds Naturalists' Field Club and Scientific Association, one of the most efficient of local scientific societies. An excellent microscope has been purchased by liberal subscriptions among the members. WE have received the Report of the 16th Session, 1872-3, of the Birkenhead Literary and Scientific Society, which numbers 134 members. The Report, among other papers, contains an address by the President, the Rev. G. H. Hopkins, on "the

Insufficiency of Facts to establish a Scientific Law," characterised by considerable acuteness and knowledge. A paper read before this Society by Dr. Ricketts, F.G.S., on "Fissures, Faults, Contortions, and Slaty Cleavage," has been printed in a separate form.

THE Annual Report for 1872 of the Birmingham Natural History and Microscopical Society, is on the whole very satisfactory. Prefixed to the Report is a very able and extremely interesting address by the retiring President, the Rev. H. W. Crosskey, F.G. S., on some of the general principles on which geology as a science depends. Some of his illustrations are very forcible and ingenious.

THE Mining Commission, consisting of Savot Bey and Osmin Bey, sent into the district of Lom, in the Danubian viceroyalty of Turkey in Europe, has been compelled, on account of the winter, to bring its labours to a close. It has, however, discovered two good coal mines, one ten and the other twenty miles from Lom. There are other mines of iron, copper, and bitumen.

ON November 26, at 11 P.M., a smart shock of earthquake was felt at Prevesa, in European Turkey. Though reported to have been violent, the shock only lasted a few seconds and did no damage. The earthquake of November 10, in Anatolia, extended to Ak Hissar, where it did some damage, and also in the village of Suleimanieh. On October 11, there was a slight shock at Lima, in Peru.

THE following statistics relating to Swedish Universities are from the Medical Record :-In the University of Upsala there are 52 ordinary and 2 extraordinary professors, 24 ordinary and 2 extraordinary assistant-professors, and other teachers, making a total of 109 persons engaged in instruction. The number of pupils is 1,607, of whom 172 belong to the faculty of medicine. The University of Lund has 64 teachers, including 28 ordinary and I extraordinary professor, and 28 ordinary assistant-professors. There are 545 students, of whom 33 are medical.

THE Journal of the Society of Arts informs us that from a recent report to the Congress by the Inspector-general of Public Instruction in Chili, some idea of the educational condition of that republic may be formed. There are 1,190 schools in Chili, of which 726 are public and 464 private. It appears from the latest census that the population of the towns is 520,668, being at the rate of one school for every 1,769 inhabitants; and in the country, with a population of 1,298,560, there would be one school for every 3,020 inhabitants. In 1872 these schools were attended by $2,162 children and young persons of both sexes, and the amount expended by the Government for education purposes amounted to 414, 127 piastres. The number of teachers in

the primary schools was 1,544, of which 896 were male and 657

female teachers.

ACCORDING to the "Reports of the Mining Surveyors and Registrars," the yield of gold in the colony of Victoria for the quarter ending June 30, was:-from Alluviums 123,643 oz. 6 dwt.; from quartz reefs, 159,604 oz. 17 dwt; total 283, 248 oz. 3 dwt.

WE have received No. 3 of Albert Müller's "Contributions to Entomological Bibliography," up to 1862.

THE additions to the Zoological Society's Gardens during the last week include an Alpaca (Lama pacos) from Peru, and a Pileated Parraket (Platycerus pileatus) from Australia, purchased; a Violaceous Plaintain-cutter (Musophaga violacea) from West Africa, received in exchange; a Puma (Felis concolor) from America, and two Tuberculated Iguanas (Iguana tuberculata) from the West Indies, deposited.

SCIENTIFIC SERIALS

THE Journal of the Franklin Institute, November 1873.-In this number Mr. Richards, mechanical engineer, communicates the first part of a treatise on "The Principles of Shop Manipulation for Engineering Apprentices ;" the points dealt with being these plans of studying (and here he advocates the order, first, machine functions, next, plans or adaptations of machines, third, construction of machines), nature of mechanical engineering, engineering as a calling, and the conditions of apprenticeship.-Dr. Coolley, in a lecture-extract, shows how convection may be usefully applied in detection of heat. He has an instrument somewhat like a Coulomb electrometer; in a glass case, a thin glass tube with black pith ball at one end is suspended horizontally by a silk fibre over a graduated disc. A heated body is introduced near the ball, which immediately swings towards it; while a cold body will repel the ball; these effects being due to air currents. The experiments Dr. Coolley makes, show that this forms a very sensitive thermoscope.-An account is furnished of the Cleveland Waterworks Tunnel, just completed, and which is similar to the one at Chicago. The shore section and lake section were carried on simultaneously, 40 ft. to 70 ft. below the bottom of the lake; the starting-points being a mile and a quarter apart. The work was somewhat disturbed by quicksands, but the sections met on an exact level. The capacity of the tunnel is 60 to 70 million gallons daily; though the average daily consumption is at present only about 6 million gallons.-A new process is described for utilising coal waste. The inventor uses, as a cement, only yellow clay with some milk of lime, but no bituminous or resinous matter; merely waterproofing the surface with a solution of rosin. From first to last no handling is required; and the lumps are delivered, in shape and size like hen's eggs. The process is highly commended.-We find notes on American machinery abroad, friction of screw propellers in water, &c., and, among other novelties of construction described, a planing bar, a compound beam engine, an antifriction journal, an irrigating machine, and a new optical toy (Prof. Dolbear).

Annalen der Chemie und Pharmacie. Band 169, Heft 1, u. 2. -We notice that in this number Liebig's name disappears from the list of editors, and the title is changed to Justus Liebig's Annalen der Chemie und Fharmacie. The following papers are published :--Hubner and Post on the constitution of bromtoluol in relation to its hydrogen atoms. The authors give a collection of minor papers by various authors, dealing with the substitution of different hydrogen atoms in the formula by various radicles.On the estimation of nitrogen, by S. W. Johnson. The author finds that a mixture of sulphate or carbonate of sodium with slaked lime can be employed instead of the soda-lime usually used in Varrentrapp's and Will's processes. The mixture, when heated, of course, yields sodic hydrate and sulphate or carbonate of calcium. Experiments made with such mixtures are described. On the nitro derivatives of naphthalin, by F. Beilstein and A. Kuhlberg. The mono-, di-, and tri-nitro compounds are described. On atacamite, by E. Ludwig. The author proposes some alteration in the ideas of the constitution of this mineral advocated by Rammelsberg and others, his suggestions being based upon the way in which the substance gives up its water at different temperatures; he also makes some suggestions as to formula of brochantite. On the action of sulphocarbonyl chloride on amidogen compounds, by B. Rathke and P. Schäfer. Note on a polyacetone, by W. Heintz.-On the production of talanin by means of potassic cyanide, and on a by product of the reaction by W. Heintz. The author gives details of the preparation of alanin, the by product is lactyt-urea.-On the constitution of natural silicates, by Dr. K. Haushofer, is a lengthy paper dealing with the probable constitutional and graphic formula of these bodies.-On the polyolenes and on the change of ethylene into ethyl alcohol, by W. Goriainow and A. Butlerow.-On protein substances, by H. Hlasiwetz and J. Habermann.-On the compounds of the camphor group, by J. Kachler. The author describes pimelinic acid, C,H,,O4, and many of its salts. -On the isomers of amylene obtained from the amylic alcohol of fermentation, by F. Flavitzky.-On the synthesis of anthracene and dimethyl-anthracene, by W. A. van Dorp.-On cœrulignon and its derivatives, by C. Lieberman. The author regards coerulignon as a quinone.-On pentabrom resorcin and pentabromorcin, by C. Lieberman and A. Dittler.-The number concludes with an abstract from M. L. d'Henry's late paper in the Comptes Rendus, on the use of the sodium flame for observing litmus tints in alkalimetry.

Verhandlungen der k. k. geologischen Reichsanstalt. Nos. I to 6. (1873.) Amongst many other papers of interest contained in these numbers of the Proceedings we note the following:— On the occurrence of a new genus and new species of palm seedvessel (Lepidocaryopsis Westphaleni) in the cretaceous sandstone of Kaunitz in Bohemia, by D. Stur.-Notices of the earthquake at Vienna on the 3rd January, by Dr. G. Stache.-Hugo Rittler's sketches of the rothliegende in the environs of Rossitz, by D. Stur. On the analogies of the three carboniferous resins, anthracox, middletonite, and tasmanite, and their probable origin, by O. Feistmantel.-On the geological position and distribution of the silicified woods in Bohemia, by the same author.-The usual literary notices and other matters, accompany each part of the Proceedings.

Ocean Highways, December. This number commences with an appreciative memoir of the late Sir Robert Maclure. An article entitled "The Straits of Magellan" contains some very interesting information concerning the little known region in that quarter of the world, and what has been done recently for the settlement of the mainland-coast of the straits. The paper recommends to emigrants Sandy Point, the Chilian settlement at which most of the steamers touch on their way to and from the West Coast, and which "is admirably situated on Brunswick Peninsula, nearly on the line of demarcation between the dense forests which cover the whole western end of the Straits, and the naked, rolling Pampas, which spread uninterruptedly northward to the very shores of the river Plate."-H. H. Giglio sends a letter, with some remarks from Dr. Beccari, on the latter's

Exploration of Papuasia. Three small maps of parts of New Guinea illustrate the discoveries of Beccari, D'Albertis, Moresby, Cerruti, and Meyer.

SOCIETIES AND ACADEMIES

LONDON

Royal Society, Dec. 11.-"On the Action of Heat on Gravitating Masses," by William Crookes, F.R.S.

The experiments recorded in this paper have arisen from observations made when using the vacuum-balance, described by the author in his paper "On the Atomic Weight of Thallium,' for weighing substances which were of a higher temperature than the surrounding air and the weights. There appeared to be a diminution of the force of gravitation, and experiments were instituted to render the action more sensible, and to eliminate sources of error.

After discussing the explanations which may be given of these actions, and showing that they cannot be due to air-currents, the author refers to evidences of this repulsive action of heat, and attractive action of cold, in nature. In that portion of the sun's radiation which is called heat, we have the radial repulsive force possessing successive propagation required to explain the phenomena of comets and the shape and changes of the nebula. To compare small things with great (to argue from pieces of straw up to heavenly bodies), it is not improbable that the attraction now shown to exist between a cold and a warm body will equally prevail when, for the temperature of melting ice is substituted the cold of space, for a pith ball a celestial sphere, and for an artificial vacuum a stellar void. In the radiant molecular energy of cosmical masses may at last be found that "agent acting constantly according to certain laws," which Newton held to be the cause of gravity.

Dec. 18.-" On Double Refraction in a Viscous Fluid in motion," by Prof. J. Clerk Maxwell, F.R.S.

According to Poisson's t theory of the internal friction of fluids, a viscous fluid behaves as an elastic solid would do if it were periodically liquefied for an instant and solidified again, so that at each fresh start it becomes for the moment like an elastic solid free from strain. The state of strain of certain transparent bodies may be investigated by means of their action on polarised light. This action was observed by Brewster, and was shown by Fresnel to be an instance of double refraction.

In 1866 I made some attempts to ascertain whether the state of strain in a viscous fluid in motion could be detected by its action on polarised light. I had a cylindrical box with a glass bottom. Within this box a solid cylinder could be made to roThe fluid to be examined was placed in the annular space

tate.

* Phil. Trans. 1872.

✦ Journal de l'Ecole Polytechnique, tome xiii. cah. xx (1829).

between this cylinder and the sides of the box. Polarised light was thrown up through the fluid parallel to the axis, and the inner cylinder was then made to rotate. I was unable to obtain any result with solution of gum or syrup of sugar, though I observed an effect on polarised light when I compressed some Canada balsam which had become very thick and almost solid in a bottle.

It is easy, however, to observe the effect in Canada balsam, which is so fluid that it very rapidly assumes a level surface after being disturbed. Put some Canada balsam in a wide-mouthed square bottle; let light, polarised in a vertical plane, be transmitted through the fluid; observe the light through a Nicol's prism, and turn the prism so as to cut off the light; insert a spatula into the Canada balsam in a vertical plane passing through the eye. Whenever the spatula is moved up or down in the fluid, the light reappears on both sides of the spatula ; this continues only so long as the spatula is in motion. As soon as the motion stops, the light disappears, and that so quickly that I have hitherto been unable to determine the rate of relaxation of that state of strain which the light indicates.

If the motion of the spatula in its own plane, instead of being in the plane of polarisation, is inclined 45° to it, no effect is observed, showing that the axes of strain are inclined 45° to the plane of shearing, as indicated by the theory.

I am not aware that this method of rendering visible the state of strain of a viscous fluid has been hitherto employed; but it appears capable of furnishing important information as to the nature of viscosity in different substances.

Among transparent solids there is considerable diversity in their action on polarised light. If a small portion is cut from a piece of unannealed glass at a place where the strain is uniform, the effect on polarised light vanishes as soon as the glass is relieved from the stress caused by the unequal contraction of the parts surrounding it.

the time from maximum to maximum, for the same hemisphere, being variable between 18 and 32 days, but having a mean value of about 25.2 days.

It occurs at once that if the variations of the mean terrestrial magnetic force are connected in any way with the solar spots, or the causes which produce them, we might here find some explanation of the magnetic period of 26 days, the difference of spot area in one hemisphere from that in the other being related to a difference of the solar magnetic action.

In order to determine whether such a connection existed, I projected first the curves of excess of spot-area given in the paper of Messrs. De La Rue, Stewart, and Loewy, and below them the daily mean horizontal force of the earth's magnetism during the same periods. The conclusion from these projections is, that there is no relation whatever between the two classes of curves. The maxima and minima of the one agree in no ways with those of the other; the greatest excesses of sun-spot area in the one hemisphere over those in the other occur when the earth's magnetic force is the most constant; the greatest variations of the earth's magnetic force from the mean occur in several instances when the sun-spot area is equal in the two visible quarter-spheres.

It should be remembered, in considering the curves of sunspot excess, that the minima and maxima are in some cases only relative; sometimes the one, sometimes the other being really cases in which there is neither maximum nor minimum; that is to say, cases in which the sun-spot area is equal, or nearly so in the two visible quarter-spheres.

The body of a sea-nettle has all the appearance of a transparent jelly, and at one time I thought that the spontaneous contractions of the living animal might be rendered visible by means of polarised light transmitted through its body. But I found that even a very considerable pressure applied to the sides of the sea-nettle produced no effect on polarised light, and I thus found, what I might have learned by dissection, that the sea-nettle is not a true jelly, but consists of cells filled with fluid.

On the other hand, the crystalline lens of the eye, as Brewster observed, has a strong action on polarised light when strained, either by external pressure, or by the unequal contraction of its parts as it becomes dry.

I have enumerated these instances of the application of polarised light to the study of the structure of solid bodies as suggestions with respect to the application of the same method to liquids so as to determine whether a given liquid differs from a solid in having a very small "rigidity," or in having a small "time of relaxation,' or in both ways. Those which, like Canada balsam, act strongly on polarised light, have probably a small "rigidity," but a sensible "time of relaxation." Those which do not show this action are probably much more "rigid," and owe their fluidity to the smallness of their "time of relaxation."

"On the Period of Hemispherical Excess of Sun-spots, and the 26-day Period of Terrestrial Magnetism." By J. A. Broun,

F.R.S.

It appears from the interesting communication to the Royal Society, June 19, by Messrs. De La Rue, Stewart, and Loewy, t that the difference of the area of spots on the visible northern and southern quarter-spheres of the sun seems, during periods of considerable solar disturbance, to obey a law such that the difference is a maximum in the same quarter-sphere during several successive rotations of the sun, the difference being a maximum alternately in the northern and southern hemispheres ;

The "time of relaxation" of a substance strained in a given manner is the time required for the complete relaxation of the strain, supposing the rate of relaxation to remain the same as at the beginning of this time. + Proc. Royal Soc. vol. xxi. p. 399.

It will be obvious also that this investigation refers only to one visible hemisphere of the sun; an approximation to the spotdistribution on the other hemisphere will, however, be frequently possible.

"On the Nervous System of Actinia," Part I., by Prof. P. Martin Duncan, F. R.S.

"On certain Discrepancies in the published numerical value of π," by William Shanks.

Mathematical Society, Dec. 11.-Prof. Cayley, F.R.S., V.P., in the chair.-Prof. Clifford gave an account of his paper on the graphic representation of the harmonic components of a periodic motion. The paper was an application of a theorem of Fourier's, which asserts that any motion having the period P may be decomposed into simple harmonic motions having periods P, P, P, &c., and assigns the amplitudes and phases of these motions by means of definite integrals.-Prof. Cayley next spoke on the subject of Steiner's surface. The author stated that he had constructed a model and drawings of the symmetrical form of Steiner's surface, viz. that wherein the four singular tangent planes form a regular tetrahedron, and consequently the three nodal lines (being the lines joining the middle points of opposite edges) a system of rectangular axes at the centre of the tetrahedron. He then described the general form of the surface, and finally discussed its analytical theory.-Lord Rayleigh, Mr. Roberts, Prof. Clifford, and Prof. Cayley made further extempore communications to the Society.

Linnean Society, Dec. 18.-G. Bentham, F. R. S., president, in the chair. -Dr. Hooker exhibited a magnificent zoophyte from Bermuda, sent by General Lefroy; also a six-lobed Seychelles cocoa-nut (Lodoicea Seychellarum) and two tazzas made from the shell of a Seychelles cocoa-nut sent from the Seychelles by Mr. Swinburne Ward to the Kew Museum; also some small boxes from Mauritius and Madagascar made from some grass-haulm; and two walking-sticks from Bermuda made of the "cedarwood" of commerce (Juniperus bermudiana).-Mr. Bowring exhibited an inflorescence of an orchid with a remarkable smell, probably a Bulbophyllum.-The following papers were then read, viz. :-"Contributions to the Botany of the Challenger Expedition," No. 2, by H. N. Moseley, M.A. On the Vegetation of Bermuda and the surrounding sea. About 160 species of flower