Motion-retrograde.

29 419 8.26678 Retrograde.

The general resemblance of these elements to those of the The middle observation shows great comet, will excite remark.

a difference from computation of 6'2 in right ascension, and - 3'2 in declination by the second orbit; perhaps unavoidable error in an estimated place, or vagueness of the nebulosity may account for the differences, yet Dr. Schmidt speaks of having observed "Die Positionen des eines Kernes des seitlichen Nebels." Further, it may be observed that the orbit in which the great comet is now moving does not accord with the positions given by Dr. Schmidt: thus with the last elements published in NATURE, the observed and computed right ascension on October 9 will agree if the perihelion passage be assumed to have cccurred September 13732, but the calculated declination is north of that observed by 1° 39', and for the observation on October II, the calculation is in error +1° 56′ in right ascension and +2° 31' in declination. Nevertheless the general similarity in the arrangement of the elements suggests a past connection of the two bodies, and it may be hoped that further light will be thrown upon the question, if either earlier or later observations of Dr. Schmidt's object are forthcoming..

COMET 1882 6.—In an unusually clear sky for the season on the morning of October 23, a fine view of this comet was obtained in the vicinity of London; the length of the more definite portion of the tail was about 164. At 5 a.m. on October 30, with strong moonlight and a somewhat vaporous sky, it was still conspicuous, notwithstanding the material diminution in the theoretical intensity of light. If the tail extended in the same direction from the nucleus on both dates, there was a large increase in its real dimensions in the course of the week. In fact, on October 30, if we assume the tail to have been a prolongation of the radius-vector, it would cover a space considerably greater than the mean distance of the earth from the sun, and with any reasonable assumption as to deviation from that line, its true length could hardly have been less than 70,000,000 miles.

The place given by M. Cruls for the comet he found at Rio Janeiro on September 12 a.m., differs 5° 43′ in right ascension, and 1° 25′ in declination from that occupied by the great comet at the time.

From an observation at the Collegio Romano, in Rome, on the morning of October 25, kindly communicated by Prof. Millosevich, it appears that the elements last published in this column were in error -2'4 in right ascension and -o''3 in declination, small differences, considering that the last observation used in their determination was made on October 1, and a proof of the precision of the observations issued from the Collegio Romano.

GEOGRAPHICAL NOTES

THE Council of the Geographical Society have made the final arrangements for their new African expedition under Mr. Joseph Thomson. Mr. Thomson hopes to leave England in the end of November for Zanzibar, where he will stay some months getting together his retinue and goods, and making other provisions for his hazardous journey. He will probably leave the coast in April or May next. The field of the new expedition lies to the east and north-east of Lake Victoria Nyanza, and may include a running survey of the eastern shore of the lake. The expedition will probably start from Pangani, and ascend the river of that name as far as Kilima Nyaro, whence they will proceed direct to Victoria Nyanza. The route after that will depend much on circumstances, but Mr. Thomson hopes to visit the reputed Lakes Bahringo and Samburu, as also Mount Kenia. Probably Mounts Kenia and Kilima Nyaro will be more carefully examined than they have been, and beyond them the country to be traversed by the expedition is almost totally unexplored. On its borders we

a

meet with the names of such travellers as Denhardt, Krapf, New, Wakefield; but the field is practically virgin. A great part of the region is a wilderness, rendered so by roving Masai, whose depredations have scattered the population and rendered culture impossible. Besides the danger from these roving freebooters, the expedition will be compelled to carry its own provisions to a large extent, as there is no likelihood of getting regular supply on the spot. Water, too, it is feared, will be scarce, so that on the whole Mr. Thomson will have a trying task before him. The expedition will be purely geographical, but it is almost certain that a naturalist will accompany Mr. Thomson as far as Kilima Nyaro, partly at the expense of the Mr. Thomson will, however, be in no

British Association.

way responsible for the safety or the conduct of the naturalist's party. It is probable that Dr. Aitchison, who did good work in natural history during the Afghan war, will be selected for this work, and his retinue and all his arrangements will be quite independent of those of Mr. Thomson; the two parties will simply go together so far as their route is in common.

On

MR. STANLEY has published separately a full report of the address he recently gave in Paris. From this we glean one interesting item of exploration. After he had launched his steamer on the upper waters of the Congo, above the cataracts, he proceeded up the river and entered the Kwango, the great southern tributary. One hundred miles from its mouth he came to where two large streams united to form the main river; a greyish-white stream from south by east, the other, of an inky colour, from east by south. Ascending the latter, much less rapid than the former, Mr. Stanley came, after steaming another 120 miles, to a large lake, into which the river widened. circumnavigating it, he found it about seventy miles in length, and with a breadth varying from six to thirty-eight miles. The natives he found very wild, and naturally astonished at the puffing monster. A splendid country the shore seemed to be -dense, impenetrable-lofty forests, alternating with undu. lating grass lands. Mr. Stanley was altogether three years away from Vivi, and doubtless he has collected much information in the country around the Congo. If the five stations established on the banks-one at the mouth of the Kwango-are left unmolested, much material of value to science may be collected ; they are superintended by Europeans, who have all the apparatus for taking meteorological and other observations.

ON Sunday, October 29, the Paris Society of Topography distributed its medals in the large Hall of the Sorbonne. M. de Lesseps was in the chair. The three great medals were awarded to M. D. Brazza, M. Roudaire, and Commander Perier. One of the others to M. Triboulet, treasurer of the Academy of Aérostation Météorologique, for his continuous efforts in aerial photography and the success obtained nineteen days ago in photographing the horizon visible from a captive balloon, with an apparatus put in operation from the ground.

AT the last meeting of the Section of Physical Geography of the Russian Geographical Society, M. Grigorieff made a report on the results of Arctic exploration during last summer; W. E. Fuss read a communication on his visit to Novaya Zemlya, which was made to determine accurately the position of the new meteorological station; and M. Rykatcheff a communication on meteorological observations he made during an ascent in a balloon.

THE students of the Physical and Mathematical Faculty of St. Petersburg have presented M. Miklukho Maclay with an address of thanks for his valuable researches, and express the wish that the results may soon be given to the world.

A RECENT issue of the North China Herald, published at Shanghai, contains an article on a Chinese work entitled "Travels in India." The work is of interest as exhibiting the impression made on an intelligent Chinese traveller by the results of Western civilisation. The author, Huang Mao-ts'ai, is, it appears, a literary graduate of Kiangsi, who became impressed with the importance to China of knowing what is going on in neighbouring countries, and accordingly obtained, in 1878, a commission from the Governor of Szechuen to pass through Thibet to India. Arriving at Patang he was deterred by the hostility of the hill tribes from proceeding further in that direction, and he therefore retraced his steps, turning southward into Yunnan, whence he crossed into Burmah, and descending the Irawaddy to Rangoon, he took passage for Calcutta. He spent

six months in India, returning to China by Singapore and Saigon.

His four volumes and maps were laid before the throne, and he was rewarded with an appointment in Yunnan. Around China he sees on all hands powerful and aggressive neighbours. To the ambitious schemes of these powerful neighbours and the means of checkmating them he devotes many pages. He dreams even of conquest, and suggests that by encouraging emigration to the southern seas, establishing consuls to look after the emigrants, opening schools to enlighten them in foreign science, and at the same time kee ing up the knowledge of their native language, the great islands of that region could be made to fall like ripe fruit into the lap of China. In the territorial acquisitions of other countries Mr. Huang finds three degrees of villainy, which he describes respectively as "stealthily beguiling," encroaching by degrees," and finally "swallowing up." Notwithstanding the offensive discrimination of these terms, he exhibits a high appreciation of English rule in India. In the latter country, he says, there are no idle officers; each has his sphere, into which no other intrudes. The will of each high functionary is limited by his council. Salaries are sufficiently liberal to prevent extortion. All are animated by a regard for their own good name. The law is faithfully executed and public spirit prompts to efforts for the general good. He is struck by the magnificence of Calcutta and its great public works. On the subject of taxes, he says: "The ground is taxed, houses are taxed, shop-signs are taxed, all manner of beasts are taxed, all handicrafts are taxed, and even fire and water are taxed. There are other taxes more than I can mention; yet you do not hear one murmuring word from the people. Why is this? It is owing to two causes: Firstly, they regard the bumane Government of the English as a great improvement on the oppressive cruelty of their native rulers: and secondly, they are aware that the revenue thus collected is expended for the good of the country-in making roads, founding schools, and so on." The author is so impressed by the railway system of India that he is extravagant in his advocacy of something similar in China. He wants a railway from the north-western frontier of China proper into Ili, as the only mears of retaining that province and Kashgaria. In reply to objections on the score of the enormous expense of this undertaking, he exclaims with true Chinese vanity: "What other countries can do, China can do, as she is ten times richer, and a hundred times more populous.'

NOTICE OF SOME DISCOVERIES RECENTLY MADE IN CARBONIFEROUS VERTEBRATE PALEONTOLOGY

IN the course of my work upon the carboniferous rocks of the neighbourhood of Edinburgh, I have succeeded in obtaining several specimens which throw some additional light upon the little known Selachians of the Paleozoic age. It was considered a great step in advance when Prof. Kner, in Germany, and Sir P. Egerton in England, proved that the spine of the tooth known as Diplodus, which occurs frequently in Carboniferous rocks, was the equally well-known Pleuracanthus, a geuns of not infrequent occurrence in the same beds. A very interesting slab from the ironstone of Burghdee, near Edinburgh, in the Carboniferous Limestone series, advances our knowledge another important stage. Upon it there are several teeth of the species Diplodus parvulus, Traq., associated with cranial cartilage, and a spine which is certainly not Pleuracanthus, but is totally unlike it, and one which does not appear to have been ever described. Upon showing it to my friend, Dr. Traquair, he said it confirmed an opinion at which he had long since arrived, that the Diplodus tooth would be found common to several genera of Selachian fishes. It certainly was a singular fact, and one which must have struck those paleontologists who have most carefully examined the fish-faunas of particular beds and horizons, that the number of the species of spines usually exceed those of teeth. Another important conclusion may be drawn from this discovery, viz. that spines are of very little value in relation to the affinities of sharks. Nothing can be more different than the spine of Pleuracanthus and that of Diplodus parvulus, Traq. These conclusions are supported by another specimen in a nodule obtained from a much lower horizon, viz. on that of the Wardic Shales at Hailes Quarry, near Edinburgh. Here we have a Hybodont tooth associated with the spine known as Tristychius. The tooth, indeed, cannot be distinguished from Hybodus; it is deeply furrowed as in many of the Mesozoic species, and has the two depressed lateral cusps. This form of tooth is

very persistent, extending from the Lower Carboniferous to the Chalk. Germar was the first, I think, to point out the existence of a Hybodont tooth in rocks of Carboniferous age, but (though I have not yet carefully examined his figures and description) the spines appear to be different from those I find associated with the Hailes specimen, though they appear to me to be of the same general type. That a Tristychine spine, with its smooth surface and strongly arcuate shape, should be associated with a Hybodus tooth is certainly unexpected, and shows again the necessity of caution in dealing with spines, for the Mesozoic spines associatewith Hybodns are very different from Tristychius. Hybodus and Diplodus are therefore generalised forms of teeth associated with spines known as Tristychius, Pleuracanthus, with one undescribed genus, probably with many others. Messrs. Hancock and Atthey, to whom British science is indebted for some of the most important ichthyological observations made since Agassiz' time suggested the possibility of Cladodus being the tooth of Gyracanthus. I have seen nothing to confirm or refute this suggestion. They also referred certain small tooth-like bodies with success to the dermal skeleton of that genus. I have obtained a nodule from the Wardic shales, which has these in a remarkably good state of preservation in connection with a large fragment of the fin of that powerful shark. These dermal denticles are so closely approximated to each other that they form a dense covering, through which however appear distinctly traces of the skeleton of the fin. The occurrence of the genus at so low a horizon is of itself deserving of record, and in addition to this fragment, I have found imperfectly preserved speciof spines of the same genus at the same place.

The remains of Labyrinthodonts are exceedingly scarce below the Burdichoun horizon. I am not aware of more than one having been discovered, and that proves to be Ophiderpeton, or a closely allied genus. This specimen was discovered in the Wardie shales, low down in the Calciferous sandstone series. The position of the Wardic shales in the Carboniferous series has not yet been exactly defined. Owing to the confused nature of the rocks, and the fact that they are so deeply covered with drift in a good deal of the Edinburgh area, it has not been found possible to settle quite clearly the relative position of the different members of the Carboniferous series. Nevertheless the opinion appears to be universal that the shales along the shore between Seafield and Granton are very low in the Carboniferous system. All that I have seen confirms this conclusion. I was amused, indeed, to see them in an otherwise well got up map, lately published, coloured as the Millstone grit! Antiquated, surely! The fossils are generally identifiable with those which are everywhere found to underlie the marine limestones (in the Scotch beds, at any rate), and from all that the drift will let one see, there must be several thou ands of feet of such rocks with the Wardic and Granton beds near the base. This being so, the occurrence of this vertebrate so low down is of interest and importance, and helps to confirm Prof. Fritsh's view, arrived at in his case from anatomical considerations, that Ophiderpeton and its allies are the roots of the Amphibian genetic tree. T. STOCK

A NUMERICAL ESTIMATE OF THE RIGIDITY OF THE EARTH1

ABOUT fifteen years ago Sir William Thomson pointed out that, however it be constituted, the body of the earth must of necessity yield to the tidal forces due to the attraction of the sun and moon, and he discussed the rigidity of the earth on the hypothesis that it is an elastic body.

If the solid earth were to yield as much as a perfect fluid to these forces, the tides in an ocean on its surface would necessarily be evanescent, and if the yielding be of smaller amount, but still sensible, there must be a sensible reduction in the height of the oceanic tides.

Sir William Thomson appealed to the universal existence of oceanic tides of considerable height as a proof that the earth, as a whole, possesses a high degree of rigidity, and maintained that the previously received geological hypothesis of a fluid interio was untenable. At the same time he suggested that careful observation would afford a means of arriving at a numerica estimate of the average modulus of the rigidity of the earth's mass as a whole. The semi-diurnal and diurnal tides present phenomena of such complexity, that it is quite beyond the powe Paper read by G. H. Darwin, F.R.S., at the British Association South ampton meeting.

I

of mathematics to calculate what these heigh s would be, if the earth's mass were absolutely unyielding. But the tides of long period are nearly free from the dynamical influences which render those of short period so intractable to calculation, and must in fact nearly follow the laws of the "equilibrium theory." In 1867 it was not, however, even definitely known whether or not the tides of long period were of sensible height at any station. Although there has been a continual advance in the knowledge of tidal phenomena since that time, it is only within the last year that there is a sufficient accumulation of tidal obser vations, properly reduced by harmonic analysis, to make it possible to carry out Sir William Thomson's suggestion. The great advances in knowledge that have been recently made are principally due to the adoption of systematic tidal observation at a great number of stations by the India Government. The results of these observations are now being issued yearly by the Secretary of State for India in the form of tide-tables for the principal Indian ports. I have had the pleasure of carrying out the examination of the tidal records, and a detailed account of the work will appear at § 848 of the new edition of Thomson and Tait's "Natural Philosophy," now in the press.

The tides chosen for discussion were the lunar fortnightly declinational tide, and the lunar montbly elliptic tide. These tides must be free from the meteorological disturbances which make the heights of all the solar tides quite beyond prediction. The fortnightly and monthly tides consist in an alternate increase and diminution of the ellipticity of the elliptic spheroid of which the sea level (after elimination of the tidal oscillations of short period) forms a part. There are two parallels of latitude respectively north and south of the equator which are nodal lines, along which thewater neither rises nor falls. When, in the northern hemisphere, the water is highest to the north of the nodal line of evanescent tide, it is lowest to the south of it, and vice versâ; and the like is true of the southern hemisphere. If the ocean covered the whole earth, the nodal lines would be in latitudes 35° 16' N. and S. (at which latitudes-sin lat. vanishes); but when the existence of land is taken into consideration, the nodal latitudes are shifted. Now according to Sir William Thomson's amended equilibrium theory of the tides, the shifting of the nodal latitudes depends on a certain definite integral, whose limits are determined by the distribution of land on the earth's surface.

For the purpose of examining the tidal records, it was therefore first necessary to evaluate this integral. Approximation is of course unavoidable, and for that end the irregular contours of the continents were replaced by meridians and parallels of latitude, and the integral evaluated by quadrature. This procedure will give results quite accurate enough for practical purposes. It appeared as the result of the quadrature that, if we assume the existence of a large Antarctic continent, the latitude of evanescent tide is 34° 40′, and if there is no such continent it is 34° 57'. Hence the displacement of the nodal latitudes due to the existence of land is very small.

This point having been settled, the mathematical expressions for the fortnightly and monthly tides are completely determinate, according to the equilibrium theory, with no yielding of the earth's mass.

If there is yielding of the earth, either with perfect or imperfect elasticity, and with frictional resistance to the motion of the water, the height of tide and the time of high water must depart from the laws assigned by the equilibrium theory. This conclusion may also be stated in another way, which is more convenient for practical purposes; for we may say that at any station there must actually be a tide with a height equal to some fraction of the full equilibrium height, and with high water exactly at the theoretical time, and a second tide, of exactly the same nature, with a height equal to some other fraction of the equilibrium height, but differing in the time of high water by a quarterperiod from the theoretical time, viz. about three-and-a-halfdays for the fortnightly, and a week for the monthly tide. These two tides may, according to geometrical analogy, be called perpendicular component tides. According to the theory of the composition of harmonic motions, the two components may be compounded into a single tide, with time of high water occurring within a half-period of the theoretical time; and this is the way in which the results of elastic yielding and frictional resistance were first stated above. Thus the actual tide at any station involves two unknown fractions, x and y, being the factors by which two components, each of the full theoretical height, are to be multiplied in order to give the two components in proper amount to represent the reality.

zero.

If the equilibrium theory is fulfilled without sensible elastic yielding of the earth, the first component has its full value, or x is equal to one, and the second component vanishes, or y is If fluid friction exercises a sensible influence, y will have a sensible value; and if the solid earth yields tidally, x will be less than unity. The amount of elastic yielding, and hence the average modulus of elasticity of the whole earth may be computed from the value of x. After rejecting the observations made at certain stations for sufficient reasons, I obtained from the Tidal Reports of the British Association and from the Indian Tide Tables, the results of thirty-three years of observation, made at fourteen different ports in England, France, and India. These results, when properly reduced, gave thirty-three equations for the x and thirty-three for the y of the fortnightly tide, and similarly thirty-three for the x and thirty-three for the y of the monthly tide; in all 132 equations for four unknowns.

The x and y of the two classes of tide were in the first instance regarded as distinct, but the manner in which they arise shows that it is legitimate to regard them as identical, and thus we have sixty-six equations for x and sixty-six for y. The equations were then reduced by the methods of least squares, with the following results :-For the fortnightly tide

x = *675056, y = '020 ± 055. And for the monthly tide

x = •680258, y = '090 ± 218. The numbers given with alternative signs are the probable

errors.

The very close agreement between the x and y for the two tides is probably somewhat due to chance.

The smallness of the two y's is satisfactory; for, as above stated, if the equilibrium theory were true, they should vanish. Moreover, the signs are in agreement with what they should be, if friction is a sensible cause of tidal retardation. But considering the magnitude of the probable errors, it is of course more likely that the non-evanescence of the y's is due to errors of observation or to the method of reduction.

I have already submitted to the British Association at this meeting a paper on a misprint, discovered by Prof. Adams, in the tidal report for 1872. This report forms the basis of the method of harmonic analysis which has been employed in the reduction of the tidal observations, and it appears that the erroneous formula has been systematically used. The large probable error in the value of the monthly tide may most probably be reduced by a correct treatment of the original tidal

records.

It has been already remarked that it is legitimite to combine all the observations together, for both sorts of tide, and thus to obtain a single x and y from sixty-six years of observation. Carrying out this idea, I find :

Taking only the Indian results (forty-eight years in all), which are much more consistent than the English ones, I find

=

x = -931056, y *155*068.

We thus see that the more consistent observations seem to bring out the tides more nearly to their theoretical equilibrium values with no elastic yielding of the solid.

It is to be observed however that the Indian results being confined within a narrow range of latitude give (especially when we consider the absence of minute accuracy in my evaluation of the definite integral) a less searching test for the elastic yielding than a combination of results from all latitudes.

On the whole we may fairly conclude that, whilst there is some evidence of a tidal yielding of the earth's mass, that yielding is certainly small, and that the effective rigidity is at least as great as that of steel.

SCIENTIFIC SERIALS

The Journal of Physiology, vol. iii. Nos. 5 and 6, August, 1882, with Supplement number. No. II contains:-Optical illusions of motion, by H. P. Bowditch and G. S. Hall,-On

reflex movements of the frog under the influence of strychnia, by G. L. Walton.-A contribution to our knowledge of the action of certain drugs upon bodily temperature, by H. C. Wood and E. T. Reichert.-Influence of Peptones and certain inorganic salts on the diastatic action of saliva, by R. H. Chittenden and J. S. Ely.-On cerebral localisation, by S. Exner.-The physiological action of methylkyanethine, by G. L. Walton.On the influence of variations of intra-cardiac pressure upon the inhibitory action of the vagus nerve, by H. Sewell and F. Donaldson.-Preliminary observations on the innervation of the beart of the tortoise, by W. H. Gaskell.-Concerning the influence exerted by each of the constituents of the blood on the contraction of the ventricle, by S. Ringer (plate xix.).—The Supplement contains a list of works and papers on physiology published in 1881.

The American Naturalist for October, 1882, contains :Sketch of the progress of North American Ichthyology in the year 1880-81, by W. N. Lockington.-On the methods of microscopical research in the zoological station at Naples, by C. O. Whitman.- On the homologies of the crustacean 1mb, by A. S. Packard, jun.-On the idols and idol worship of the Delaware Indians, by C. C. Abbott.

Journal de Physique, September.-Dynamo-electric machine; with continuous currents, by M. Potier.-Influence of a metal on the nature of the surface of another metal placed at a very small distance, by M. Pellat.

SOCIETIES AND ACADEMIES

LONDON

Mineralogical Society, October 24.-Anniversary Meeting. W. H. Huddleston, F.G.S., president, in the chair. -Nine new Members were elected.-The officers and Council were elected for the ensuing year, the only changes being the election of Messrs. T. D. Gibb, T. M. Hall, Jas. I'Anson, and H. M. Plattnault, on the Council in place of Dr. Aitken, Professors Crum Brown and Hughes, and Mr. Louis, who retired in rotation. It was resolved to hold the meetings of the Society at fixed dates for the ensuing year, viz, on December 13, 1882, February 15, May 15, and October 23 (Anniversary), the meeting for May to be held in Scotland.-The Report of the Council was read and adopted.

PARIS

Academy of Sciences, October 25.-M. Blanchard in the chair. Herr Wiedemann presented the first volume of a new work by him, "Die Lehre von der Electricität."-On the effect of a stroke of an inclined cue on a billiard ball, by M. Résal. Separation of gallium (continued), by M. Lecoq de Boisbaudran. -Contribution to the study of typhoid fever in Paris; the present epidemic, from September 22 to October 19, 1882, by M. de Pietra Santa. There have been 2225 deaths this year (up to the latter date), more than during the whole of last year 2130), (628 in the last four weeks). All the twenty arrondissements have been affected, and all the eighty quarters, except the four American and that of St. Fargeau in the west and Salpêtrière and Petit-Montrouge in the south. The seventh arrondissement has suffered most. M. Santa notics the unwholesome state of the houses.-On a bed of coal discovered in the province of Algiers, and on layers of white sand accompanying it, by M. Pinard. This is near Bou Saada. The coal is at least equivalent in illuminating power and yield of gas to the best French and English coal. The yield of coke varies between 62 and 66 per cent. The sand, which might be used for the finest glass, and is very abundant, is the product of disaggregation of immense banks of grit.-Results of modes of treatment adopted in 1881-82, in the Alpes-Maritimes, for destruction of phylloxera, by M. Laugier. More than 200 hectares have been treated with sulphide of carbon and sulphocarbonate of potassium, and the results are very satisfactory.-Observations of the great comet (Cruls) at the Observatory of Marseilles, by M. Borrelly.Spectroscopic observations on the same comet, by MM. Thollon and Gouy. On October 9, the sodium lines seen on September 11, had disappeared; the four ordinary carbon bands were present; the nucleus gave a narrow continuous spectrum with many dark and bright lines. On the 16th the violet band was almost gone, and the continuous spectrum considerably weakened. The disappearance of the sodium lines and others observed by M. Lohse shows that under ordinary conditions the spectroscope cannot give us a complete analysis of cometary

matter.

==

If the temperature is sufficient to produce the emission spectrum of carbon compounds, it should be sufficient to produce that of sodium; but the facts are contrary. The authors incline to the electric theory of comets; in the case of a gaseous carburet traversed by the effluve from a Holtz machine, and holding fine metallic dust in suspension, the carbon bands appear, but not the metallic lines.-Relations between the residues of a function of an analytic point (x, y), which is reproduced, multiplied by a constant, when the point (x, y) describes a cycle, by M. Appell.-On the hyper-geometric functions of two variables, by M. Goursat.-Decomposition of a whole number N into its maximum wth powers, by M. Lemoine.-Lunar induction and its periods, by M. Quet.-On the automatic transmission and registration of messages of optic telegraphy, by M. de Brettes. A claim of priority.-On metallic thorium, by M. Nilson. He has reduced thorium by heating with odium, the anhydrous double chloride of thorium and potassium, and adding to the mixture chloride of sodium; all in an iron crucible. The specific gravity of the pure metal is about 1100; the substance, as prepared by Chydenius (density 7'657-7'795), was probably impure. For atomic volume, M. Nilson gets the value 211 (coinciding with the atomic volumes of zirconium (217), cerium (211), lanthanum (226), and didymium (215)). -Determination of the equivalent of thorium, by the same. The equivalent is equal to 58 10, if that of oxygen = 8 and that of sulphur 16. On benzylene orthotoluidine and methyl phenanthridine, by M. Etard.-On the reduction of nitrates in arable land, by MM. Deherain and Maquenne. An earth loses the property of reducing nitrates when it has been heated or submitted to chloroform vapours. Earth that has lost the property through heat, reduces anew when a little normal earth is added. On the convulsing action of curare, by M. Couty. Curare is not only a paralysing poison, but also in the first place, slightly convulsing; nor merely a peripheric poison, but also, in certain measure, a poi on of the nerve-centres.-On parasites of the blood in impaludism, by M. Laveran. He has observed them in 300 cases.-Isanemones of summer in the North Atlantic, by M. Brault. These curves of equal velocity of wind coincide with the isobars.-On turriform constructions of earth-worms in France, by M. Trouessart. He observed them in gardens in Angiers, and found they were produced by Lumbricus Agricola. Darwin knew only of this production by a Perichaeta naturalised at Nice, from the east. M. Gautrelat, in a note, affirmed that M. Le Bon's glyceroborate of soda is not a definite salt, but a mixture of monoborine (monoboric ether of glycerine), sub-borate of soda, and glycerine.-A map, by M. Durand Claye was presented, showing the increase of popula tion in the department of the Seine, and adjacent parts of the department of Seine-et-Oise. The variations of growth are indicated by means of curves called isoplèthes.—Some documents from M. de Lesseps, relating to construction of the hospital of Panama, by the Canal Company, were presented.

CHEMICAL SOCIETY, at 8.-On some Halogen Compounds of Acetylene: Dr. R. T. Plimpton.-On Dihydroxybenzoic Acids and Iodosalicylic Acids: Dr. A. R. Miller.-Crystalline Molecular Compounds of Naphtha. lene and Benzene with Antimony Chloride: Watson Smith and G. W. Davis. Additional Evidence that Quincline belongs to the Aromatic Series of Organic Substances: Watson Smith and G. W. Davis - On Orcin and some of the other Dioxytoluols: R. H. C. Nevile and Dr. A. Winther.

LINNEAN SOCIETY, at 8 -On Ants, Bees, and Wasps. Part X : Sir John Lubbock, Bart.-Medicinal Plants of Queensland: W. A. Armit.-Malformation Leaves of Beyeria opaca : J. G. Otto Tepper -Hybridisation of Salmo fontinalis: Dr. F. Day.-Teratological Notes on Plants: H. N. Ridley.-Remarks on Marine Fauna of Norway: Prof. Lankester. FRIDAY, NOVEMBER 3.

GEOLOGISTS' ASSOCIATION, at 8.-The Geology of Palestine: W. H. Hudleston.

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(Close to South Kensington Museum.)

THE PHONEIDOSCOPE

An Instrument for Observing the Colour-Figures of Liquid Films under the
action of Sonorous Vibrations,
Being a visible demonstration of the Vibratory and Molecular Motion of a
Telephone Plate

The PHONEIDOSCOPE, with 3 Discs, Bottle of Solution, Descriptive Pamphlet, &c., in Cardboard Box, 10s. 6d.

MANUFACTURED AND SOLD WHOLF SALE AND RETAIL BY

S. C. TISLEY & CO., 172, BROMPTON ROAD, LONDON, S.W. TELEPHONIC ELECTRICITY. All Materials supplied for Experimental Purposes.

Price Lists of Electrical and Acoustic Apparatus, with Drawings and Description of the Harmonograph. Post Free, 2d.

NOTICE OF REMOVAL. JAMES HOW & CO.,

SCIENTIFIC INSTRUMENT MAKERS, 73, FARRINGDON STREET, LONDON (LATE OF 5, BRIDE ST., AND 2, FOSTER LANE). HOW'S STUDENT'S MICROSCOPE. HOW'S MICROSCOPE LAMP Rock Sections and other Objects for the Microscope.

&

CO.,

LONDON, W.C.