cause of the negative potential exhibited by the voluntarily contracted muscles of one limb when compared with the opposite but unexerted limb, and is therefore the current which du BoisReymond took for the muscular functional current of man.1 B.-NERVES The Functional Current of Nerves remote from all Transverse Sections In the nerves of the frog, according to Helmholtz, excitatory waves are propagated at the rate of twenty-eight metres per second. Hence, if the two ends of a galvanometer circuit were laid upon two points of a nerve a functional current should be manifest on stimulation of the nerve, and should consist of two phases according as the excitatory wave was passing one or the other of the electrodes. Nevertheless the functional current of nerves, owing doubtless to its exceedingly fleeting character, has hitherto escaped detection. Since the excitatory wave of nerves does not diminish in its course, it is to be expected that the two phases of the nervous functional current will be equal; and hence also it is that in tetanic stimulation, where we have to do with the algebraical sum of these two equal and opposite phases, we obtain no functional current whatever in uninjured nerves. The Functional Current of Nerves at a Transverse Section The functional current of nerves bounded by an artificial transverse section was discovered by du Bois-Reymond; it is an equalising current, and consists, therefore, in a diminution of the constant demarcation current. Du Bois-Reymond only found this current in nerves tetanically stimulated, but Bernstein, by means of his apparatus already referred to, succeeded in demonstrating its presence in the case of single excitatory waves.3 If the poles of the galvanometer circuit are applied, one to the artificial cross-section, and the other to a point in the longitudinal surface, the diminution of the demarcation current occurs in the instant that the excitatory wave passes the latter, or longitudinal pole. By altering the position of this pole, the progress and the course in time of the excitatory wave may be examined. The rate of progression so deduced was found to agree with that determined in other experiments by varying the distance between the point of the nerve at which a stimulus was applied and the fixed point at which the result of stimulation was manifested, viz., the dependent muscle, or the pole applied to an artificial cross-section. And this similarity of result established the identity of the process occurring during excitation, and the wave of negative deflection. The way in which the wave comports itself on approaching the artificial cross-section will be explained below. The Functional Current of Polarised Nerves: the Polarisational Increment of Excitation In 1866 Bernstein found that the electrotonic currents of nerve, on stimulation of the nerve, suffer diminution like the demarcation-currents. As a disciple of the molecular theory he explained this phenomenon in the following way: Since the electrotonic currents depend upon an altered arrangement of the molecules, and since the force of each molecule diminishes on stimulation of the nerve, therefore the electrotonic currents must also be lessened during excitation. And so the new phenomenon seemed to be completely covered by the molecular theory. In my view, however, the electrotonic currents are merely offsets diverted from the main polarising current owing to the internal polarisation of the nerve itself. Since these offsets could not be supposed to be modified during excitation, I concluded that every apparent diminution depended upon a functional current which arises owing to the polarised condition of the nerve, and which is opposite to the polarising current in direction. I assumed, as the cause of this functional current, that the excitatory wave failed of maintaining its magnitude while passing through the polarised portions of nerve; it in creased as it reached more positively or less negatively polarised areas, and diminished under the opposite conditions. This is called the doctrine of the “polarisational increment of excita These experiments have been recently published; cf. Hermann and Zuchsinger, Arch. f. d. ges. Physiol.," xvii. p. 310, 1878. 2 I have succeeded in detecting these currents by extending the rate of propagation in the nerve by cold; and by using a bundle of four or six nerves together. Cf. "Arch. f. d. ges. Physiol.," xvii., p. 574, 1878. 3 J. Bernstein, loc. cit. 4 The new experiments referred to in the last note confirm this indirect conclusion in a more direct manner. 5 J. Bernstein, "Arch. f. Anat. u. Physiol." p. 596, 1866. tion," and it is clearly competent to explain Bernstein's observations. If this assumption be reasonable, the excitatory condition travelling along the nerve should be most intense at the anode of the polarising current, and least intense at the cathode; and hence there should be present in the intrapolar region a powerful functional current of like-direction with the polarising current and reinforcing it. Such an intrapolar current I did, in fact, discover to be constantly present; though afterwards it appeared that a similar observation had previously been made by Grünhagen, by whom, however, the current was otherwise explained as the effect of a diminished resistance in the nerve during excitation, leading to an increase in the polarising current. Before I had any knowledge of this early observation of Grünhagen, the probability of the explanation which he assigned to it had been tested by me, and numerous indications had been found that the intrapolar increase of current was indeed an electromotive phenomenon and not due to a diminished resistance. But later I was enabled to settle the question in the most direct manner, by the discovery that the transverse resistance of nerves is not diminished during excitation-excitation having in general no manner of influence upon the resistance offered by the nerve.5 Further Physiological Support of the Doctrine of Polarisational Increment In order to grasp the doctrine of polarisational increment, let us regard the axis n n' in Fig. 5 as representing a nerve, the conditions of polarisation of which are indicated by the vertical ordinates, positive polarisation being exceptionally represented by descending lines, and negative by ascending lines. With these ordinates we can trace out the polarisation curve, n Ki An (already spoken of in describing Fig. 5, which see), the lowest point of which corresponds to the anode, and the highest to the cathode. Let us now suppose a ball, e, devoid of friction, and travelling through space with a certain horizontal initial velocity, to be set rolling along this curve. The tis viva of the ball will then represent the magnitude of excitation. It is at once evident that the initial velocity is increased in the part of the curve below the line nn', i.e., in the anelectrotonic region, but is diminished in the upper portions of the curve, i.e., in the catelectrotonic region. If the initial velocity is too small, the ball will not be able to reach the summit of the catelectrotonic portion of the curve, or, in other words, the excitation becomes dissipated in the corresponding region of nerve, and never succeeds in passing the cathode. Moreover, if the ball, with a certain initial velocity, were to be set going at some point of the inferior (anelectrotonic) portion of the curve, it would reach the outlying parts beyond the polarised region with a diminished velocity; while, if it were set going upon a part of the curve (catelectrotonic) superior to the line n n', it would reach the outlying parts with an increased velocity. All these deductions from the doctrine under discussion have been verified, in part by already established facts and in part by recent observations. The experiments by Eckhard and Pflüger have shown that a certain stimulus applied to a nerve produces a greater effect in the cat electrotonic region than in the anelectrotonic. And it is clear that these phenomena are as intelligible under my theory as under the assumption usually made to explain them, viz., that the irritability of the nerve itself is diminished during anelectrotonus and increased during catelectrotonus.6 Moreover, certain facts are known which seem to imply that, with a sufficient degree of polarisation, or with a suffi ciently slight stimulus, the excitatory wave becomes blocked at the cathode. If to this we add that excitation does not indefinitely increase with the stimulus, but soon reaches a maximum, we may further conclude that, under certain condi tions, a diminution of excitation must take place even during the passage of the wave through the anodic area.8 In the last place it is to be noticed, that the artificial section of a nerve induces a negative polarisation or catelectrotonus of "Arch. f. d. ges. Physiol.," vi., p. 359, 1872; vii., p. 323, 1873 2 Ibid., vi., p. 560, 1872; vii., p. 355. 1873; x., p. 215, 1875. 3 Grünhagen, Zeitsch. f. rat. Med." (3), xxxvi., p 132, 1869. 4"Arch. f. d. ges. Physiol.," x., p. 215, 1875. 5 Ibid., xii., p. 151, 1875. 6 Ibid., vii., pp. 325, 497, 1873. Ibid., vii., p. 354, 1873; x., p. 226, 1875. Ibid., vii., p. 361, 1873. April 17, 1879] NATURE the fibres in the neighbourhood of the section, owing to the extension of the demarcation-current along the nerve.1 By this electrotonic extension we can explain-or for the most part explain-the so-called "weak currents" of the longitudinal section. A stimulus applied to the nerve near the line of secG P FIG. 8. tion, according to the law of polarisational increment, should have a greater effect than when applied to points more remote, and this experiment shows to be the case. Finally, an excitatory wave travelling along the nerve towards the cut end of it must, according to the same law, gradually diminish before it disappears entirely in the area of section itself. V. CONCLUDING REMARKS The whole of the electrical phenomena of muscle and nerve, therefore, may be readily deduced from a few very simple propositions. Irritable protoplasm responds both to destructive The and to exciting influences by an electromotive sign. altered substance takes on a negative potential with respect to the unaltered. This, together with the doctrines of internal transverse polarisation and of the polarisational increment of excitation, appears fully competent to explain all the facts hitherto observed. That these fundamental doctrines have the closest reference to the whole life of irritable tissues no one will be disposed to doubt. Yet much examination will be needed to disclose the exact nature of the interdependence. Although it must now be confessed that the theories which were based upon facts discovered more than thirty years ago, have failed to withstand the criticism of a wider experience, the domain of animal electricity has not lost, but rather gained in interest. And the services of the man who not only discovered this region of physiology, but created the means of conquering it, and who made himself master of its most important fundamental features, are in no danger of becoming dimmed in our estimation by the theoretical changes we have been compelled to accept. BAROMETRIC PRESSURE IN a work of great importance,3 recently published by Prof. Bert, on the physiological effects of barometrical pressure, the author sums up the conclusions to be drawn from his researches as follows: A. The diminution of barometric pressure acts on living beings only by diminishing the tension of the oxygen in the air which they breathe, in the blood which animates their tissues (anoxytienne of M. Jourdanet), and by thus exposing them to the dangers of asphyxia. B. The increase of barometric pressure acts only by increasing the tension of the oxygen in the air and the blood. Up to about three atmospheres this increase of tension gives rise to intra-organic oxidations a little more active. Beyond five "Arch. f. d. ges. Physiol.," vii., p. 363, 1873. This polarisation, of course, still occurs even when the demarcation-current is not abducted, or when the abducted portion is counterbalanced by an opposite current. In the latter case, according to Bosscha's law, the nerve behaves just as if no "Arch. f. d. ges. Physiol.," ix., p. 29, abducting circuit were applied to it. 1874 X., p. 237, 1875. In Fig. 8 the core of the nerve-fibre is obliquely shaded. Even in the absence of polarisation of the core the boundary current would become distributed after the manner shown in the figure, and would pass into the galvanometer circuits G and G' as the so-called weak longitudinal and transverse currents of du Bois-Reymond. But, with polarisation, the extension along the core is very much greater than without it, and at the same time the polarisational curve is produced. 3 "La Pression Barométrique; Recherches de Physiologie Experimentale." Par Paul Bert, Professor à la Faculté des Sciences de Paris. (Paris: G. Masson. 1878.) in their nature, and, when the pressure rises sufficiently, are atmospheres the oxidations diminish in intensity, probably change completely arrested. It follows that all living beings, aërial or all the anatomical elements, isolated (blood-globules, &c.) or aquatic, animal or vegetable, complex or mono-cellular-that grouped in tissues, perish more or less rapidly in air sufficiently compressed. This rule appears only to suffer exception for the reproductive corpuscles of some microscopic beings. For the higher animals death is preceded by tonic and clonic convulsions of extreme violence. Among vertebrates the rapid accidents due to the too great tension of oxygen only commence to manifest themselves at the moment when the hæmoglobin, being saturated with oxygen, that gas enters into the state of simple dissolution in contact with the tissues. C. Diastases, poisons, and true virus resist the action of oxygen at high tension. D. The inconvenient effects of diminution of pressure may be efficaciously combatted by the respiration of an air sufficiently rich in oxygen to maintain the tension of that gas at its normal value (209). Those of the increase of pressure may be combatted by employing air sufficiently poor in oxygen to arrive at the same result. E. Generally the favourable or noxious gases (oxygen, carbonic acid, &c.) act only on living beings in accordance with the tension which they possess in the surrounding atmosphere, a tension which is measured by multiplying their centesimal proportion by the barometric pressure; the increase of one of the factors may be compensated by the diminution of the other. F. When animals possess reservoirs of air either completely closed (swimming bladder of acanthopterygians, &c.) or in communication with the air during decompression alone (swimming vessel of the Cyprini, intestines of aerial vertebrates, &c.), or in communication with the air during both compression and decompression, but by very small orifices (lungs of aerial vertebrates, &c.), the diminution or increase of pressure may have physico-mechanical effects. G. Sudden decompression from several atmospheres has only the effect (except for some cases comprised under conclusion F) of allowing to return to the free state the nitrogen which was, under favour of pressure, dissolved in the blood and the tissues. H. The beings actually existing in a wild state on the surface of the globe are accommodated to the degree of oxygenated tension under which they live; all diminution, all increase, appears to be unfavourable to them when they are in a state of health. Therapeutics might make something out of these modi fications in various patholgical conditions. I. Barometric pressure and the proportion per cent. of oxygen have not always been the same on our globe. The tension of that gas has apparently been, and will without doubt continue There is here a factor which we have to go on, diminishing. not yet taken into account in biogenetic speculations. The power of reaction against these various modifications leads to the supposition that microscopic beings must have appeared first, and that they will be extinguished by the insufficient tension of oxygen. K. It is inaccurate to teach, as is ordinarily done, that vege. tables must have appeared in the earth before animals, in order to purify the air of the great quantity of CO, which it contained. In fact, germination, even that of mildew, does not take place in air sufficiently charged with CO2 to be fatal to warm-blooded animals. It is quite as inaccurate, as I have observed long ago, to explain the anteriority of reptiles with warm-blooded animals by the impurity of the air tainted with too much CO,; reptiles, in fact, are more injured by this gas than birds, and still more so than mammals. SCIENTIFIC SERIALS THE Sitzungsberichte of the Vienna Imperial Academy of Sciences (Natural History Section, vol. lxxvi. parts 1-5, and vol. lxxvii. parts 1-4) contain the following more important papers :Addenda to our knowledge of annelids, by Dr. Aug. v. Mojsisovics. On the orthoptera of the Senegal River, by Dr. H. Kraus. -On the fauna of the Cypris slates of the Eger tertiary strata, by O. Novák.-On the natural history of glimmer, by G. Tschermak.-Researches on cystolithes and some similar formations in the vegetable kingdom, by K. Richter.-On the genesis of salt deposits, particularly of those in western North America, by F. Posepny.-On the fresh-water fish of South-Eastern Brazil, by Dr. F. Steindachner.-On the "Salse di Sassuolo" and the " Argille scagliose," by Theodor Fuchs.-On the flora of the countries round the Mediterranean and their dependence from the soils, by the same.-On the fossil flora of Parschlug, in Styria, by Dr. C. von Ettingshausen.-On the development of the embryo of Asplenium shepherdi, Spr., by F. Vouk.-On the internal cells in the antheridium cell of the pollen grain of certain coniferæ, by A. Tomaschek.-On the origin of aptychus-limestone, by Th. Fuchs. On the light line in the prism cells of seed scales, by Dr. R. Junowics.—On the encircled specks in the wood of trees, by Dr. J. Kreuz.-On the firmness and elasticity of vegetable tissues and organs, by Th. Weinzierl.-On the resinous ducts of certain coniferæ, by Dr. Kreuz.-On the development of the pollen of Colchicum autumnale, L., by A. Tomaschek.-On some accessory appendages to the skull of Leporida, by Dr. A. von Mojsisovics.-On cork and cork tissues, by Dr. F. von Höhnel.-Histo-chemical researches on xyllophiline and coniferine, by the same.-On the phanerogamic flora of the Sandwich Islands, by Dr. H. W. Reichardt.-On the protoplasm of the pea, by Dr. Ed. Tangl.-On the undulating nutation of the internodes of the stems of plants, by J. Wiesner.-On the be haviour of Phloroglucine and of some similar substances towards the woody cell membrane, by the same.-On the degeneration in the leaf-shoots of some Amygdaleæ, caused by species of Exoascus, by E. Rathay.-Researches on Tunicata, by C. Heller.-On some new genera and species of Neuroptera, by Dr. F. Brauer.-On the originals to Ign. von Born's Testaceis Musei Cæsarei Vindobonensis, found in the Imperial Zoological Museum, by the same.-On the embryology of ferns, by H. Leitgeb.-Geological researches in the western part of the Balkan and the surrounding districts, by Franz Toula.-On some peculiar apertures in the corolla leaves of Franciscea macrantha, Pohl, by M. Waldner.-On the basaltic lava of the Eifel Mountains, by E. Hussak. On the origin of holes and indentures in the leaf of Philodendron pertusum, Schott, by F. Schwarz.-Ichthyological researches, by Dr. F. Steindachner.On the subterranean water-courses and basins, as well as on the clearness and transparency of certain lakes, and on the formation of lakes generally, by Dr. A. Boué. Sitzungsberichte der physikalisch-medicinischen Societät zu Erlangen (part 10, November, 1877-August, 1878) contain the following more interesting papers-On the fertilisation and division of the ovum of toxopneustes, by Dr. E. Selenka.-On the history of development of Jacobson's organ, by Dr. R. Fleischer.— On the theory of absorption and fluorescence, by E. Lommel.-On the physiological action of nitro-benzole and of aniline, by W. Filehne. On the so-called soor-fungus and its identity with Mycoderma vini, by M. Reess.--On the changeability of the angles of crystals, by Dr. Fr. Pfaff.-On the theory of normal and abnormal dispersion, by E. Lommel.-Various mathematical papers, by M. Noether and Prof. E. Lüroth.-On the modification of sound phenomena in the human body, by F. Penzoldt.On the theory of double refraction, by E. Lommel.-On the equations of the seventh degree, by F. Klein.-On some experiments made with drosera, by Drs. C. Kellerman and E. von Ramner. On chelidonic and malic acids, by Dr. O. Liezenmayer.-Thermophysiological investigations, by J. Rosenthal On the derivates of cymol and of toluylic acid, by E. von Gerichten. On the sexual organs of dibranchiate cephalopoda, by Dr. J. Brock.-On two new fluorescent substances, by E. Lommel.-On the influence of the changes in temperature and pressure upon the double refraction of light, by Dr. E. Pfaff, Jahrbuch der k.k. geologischen Reichsanstalt (vol. xxviii. part 4, October-December, 1878) contains several highly interesting treatises, viz. :-On Alpine phosphates, by J. Gamper. -On the production of common salt from the Russian steppe lakes, by Dr. C. O. Cech.-Observations on the Jurassic formation in the Carpathian cliffs, by Victor Uhlig.-On the artesian well in the Stadtwäldchen near Budapest, by Wilhelm Zsigmondy.-On Emanuel Kaiser's views on the hercynian fauna, and the limit between the Silurian and Devonian formations, by Dr. E. Tietze. Reale Istituto Lombardo di Scienze e Lettere. Rendiconti. Vol. xii. fasc. iii. We note the following papers in this number :New phenomena observed in treatment of wine and must, with lime (continued), by Prof. Pollacci.-New physio-pathological researches on pulmonary phthisis (continued), by Prof. Giovanni. -Project of an electrical indicator of the level of water in a flood, by Prof. Ferrini.-Amplitude of oscillations of the declination-needle during 1877 and 1878, at the observatory of Brera, in Milan, communicated by S. Schiaparelli. --Determi tion of the difference of longitude between Milan Observatory and those of Padua, Monaco, and Vienna, by Prof. Celoria. Fasc. iv.-First lines of introduction to the study of Italian bacteria (continued), by S. Trevisan.-Composition of butters in Lombardy, and analysis of butter in general, by Dr. Menozzi. -New researches on the rot of vines, by Prof. Garovaglio.Researches on polar systems, by Prof. Jung.-On provision against trichina, by Prof. Bizzozero. Fasc. v.-A new process of microscopic art, by Prof. Golgi.Fruitful copulation of a dog with a cat, by Prof. Lemoigne.On the intestinal anguillula, by Prof. Cantoni. Atti della R. Accademia dei Lincei, February, 1879.-Necrological memoir of Gastaldi, by S. Sella.-On the expression of one of the limits in the correction of the elliptical co-ordinates in the theory of planetary perturbations, by S. De Gasparis.On the composition of rocks of the mines of Montecortini, by S. Cossa. Rivista Scientifico-Industriale, Nos. 4 and 5, 1879.-We note in these numbers a memoir by Prof. Perotti, on governing combination of the elements of gaseous mixtures. No. 6.-On a baricentric property of the triangle, by Prof. E. Cavalli.-On a new experiment on electrolysis with weak electromotors, by Prof. A. Bartoli.-On_the_telephone and microphone as musical instruments, by G. Mocenigo.-Description of some new plants recently introduced into horti culture, by E. O. Fenzi. There plants are Gentiana algida, Primula capitata, and P. stuartii, Nicotiana acutifolia and N. suaveolens, Eremurus robustus.-On two new species of Myriapoda, Polydesmus siculus and Atractosoma nigrum, by Prof. F. Fanzago.-On a new reagent for cobalt, by Mr. Tattersall.-On poisonous colours, by the editor. Archives des Sciences physiques et naturelles, March.-From this part we notice the following papers of interest:-On the influence of coloured light upon the development and growth of animals, by Emile Yung.-On the effects of induction coils upon the nervous system, by M. Schiff.-On an acceleration of the process of tanning by means of phosphoric acid, by E, Ador. -On methyl-aniline and toluidine and the colouring-matters derived from these compounds, by MM. Reverdin, Monnet, and Nölting. On alizarine blue, by M. Graebe.-The other papers contained in the part have been noticed by us elsewhere. SOCIETIES AND ACADEMIES Mathematical Society, April 10.-C. W. Merrifield, F.R.S., president, in the chair.-Mr. Donald McAlister was elected a Member, and Messrs. A. J. C. Allen and E. Anthony were proposed for election.-The following communications were made :-Notes on quantics of alternate numbers, used as a means for determining the invariants and covariants of quantics in general, by the late Prof. Clifford, F.R.S. (communicated by Dr. Spottiswoode, P. R.S.).—Note on geometrical maxima and minima, Mr. J. Hammond.-On a class of fractions, Mr. R. Tucker. Linnean Society, April 3.-William Carruthers, F.R.S., vice-president, in the chair.-Mr. W. T. Th'selton Dyer exhibited the inflorescence of Gynerium saccharoides, grown at Kew, ing through Mr. Spruce's researches on the Amazons, little is but which had died during the winter severe weather. ExceptPampas grass in habit, and is tropical like maize, &c.-Dr. H. known respecting this handsome plant, which differs from the Trimen, in dealing with the subject of the myrrhs of commerce Nees. It was gathered by Hildebrandt in Somali Land, 1873, and pharmacy, showed the unique Balsamodendron myrrha, however, saw the myrrh exuding from the tree itself. and possesses but few leaves and a single fruit; the traveller, original type specimens of B. myrrha, collected by Prof. Ehrenberg in Arabia, were also exhibited, and, according to Dr. Trimen, Hildebrandt's late statement of their identity with the foregoing seems well founded. Ehrenberg's other myrrh plant, the B. Ehrenbergianum, Berg., with his notes attached, and the B. Playfairii, Hook. fil., from Somali Land, with its gum called "Hotai," and other examples of varieties of myrrh and bdellium were placed before the Society and commented on by Dr. Trimen. He specially adverted to the liberality of the authorities The April 17, 1879] NATURE of the Royal Berlin Herbarium and of the Hanbury Collection for being enabled to study the rare valuable specimens laid before the Fellows of the Linnean Society.-The account of a remarkable peat flood in the Falkland Islands, by Mr. Arthur Bailey, was communicated by Mr. W. T. Thiselton Dyer. About midnight, November 29, 1878, it was discovered that a black moving mass of peat, several feet high, was making its way towards the settlement at the rate of between four and five miles an hour. The next morning (30th) it was found that the town of Stanley was cut in two, intercourse between its east and west ends alone being possible by boats. Fortunately no lives were lost, and by the energy and activity of the inhabitants in the formation of a trench, much injury and destruction were considerably arrested. The Secretary read in abstract some notes on Moquilea, with a description of a new species by Mr. John Miers. The author specially compares and marks the differences between the genera Moquilea and Licania, they having often been confounded, and he afterwards points out the distinctive characters constituting his new species, Moquilea organensis. Chemical Society, April 3.-Mr. Warren De La Rue, president, in the chair.—The following papers were read :-On terpin and terpinol, by Dr. Tilden. The author has continued his previous researches, and has succeeded in obtaining crystals of terpin hydrate from essence of lemon; the author considers terpinol to have the constitution of an alcohol. Oil of lemon cajeputol, oil of coriander, and citronella contain bodies closely resembling terpinol.—On a gold nugget from South America, These nuggets are found in alluvial soil in by Mr. G. Attwood. Venezuela. Numerous gold-bearing quartz-veins are found in About one-half of the nuggets are the neighbouring hills. covered with a dark brown substance resembling a silicate of iron. When this is dissolved much finely divided gold separates, and the nugget is partly covered with dull fine gold. The gold obtained from the quartz is less pure than that of the nuggets. The author concludes that gold nuggets gradually increase in size owing to the accumulation of fresh particles of finely-precipitated gold.-On lead tetrachloride, by Mr. W. W. Fisher. The author has not isolated this compound, but has obtained it in solution by dissolving lead dioxide in hydrochloric acid; the yellow solution thus formed precipitates brown hydrated peroxide The author of lead when treated with solutions of alkalis, &c. also suggests the use of chlorine or bromine in the presence of sodium acetate as a means of quantitatively determining lead by precipitation as a peroxide.-On the transformation of aurin into trimethyl pararosanilin, by Messrs. Dale and Schorlemmer. This is effected by the action of an aqueous solution of methylamine at 125° on aurin.-On the solution of aluminium hydrate by ammonia and a physical isomeride of alumina, by C. F. Cross. By boiling the ammoniacal solution of aluminia hydrate a precipitate is obtained, which on drying and ignition furnishes alumina which is extremely hygroscopic, absorbing 35 per cent. of water.-Researches on dyeing, Part ii. Note on the emission of colouring matter, by Dr. Mills and Mr. Campbell. The experiments were made with silk and a dilute solution of Nicholson's blue. The authors affirm that a real and uniform dyeing effect can always be obtained with silk and Nicholson's blue, the heat and souring used by dyers being unadvisable. The authors recommend the addition of common salt to the vat. Geological Society, March 26.-Henry Clifton Sorby, F.R.S., president, in the chair.-William Adamson Barron, Gregory Dent, Julian John Leverson, and Rear-Admiral Francisco Sangro Tremlett, R.N., were elected Fellows of the Society. The following communications were read :-Results of a systematic survey (in 1878) of the directions and limits of dispersion, mode of occurrence, and relation to drift-deposits of the erratic blocks or boulders of the west of England and east of Wales, including a revision of many years' previous observations, by D. Mackintosh, F.G.S. The author's researches lead him to the following conclusions :-Boulders from the NorthCriffel range and Lake-district can be traced from the Solway Firth to near Bromsgrove (about 200 miles), and over an area in greatest breadth (from near Macclesfield to Beaumaris) of 90 miles, those from Criffel being particularly abundant near Wolverhampton. Boulders from the Arenig occupy a triangular area, limited by a line drawn northward from Chirk to the Dee estuary, and to the south-east of that town are found as far as The dispersion of the more Birmingham and Bromsgrove. distant Criffel boulders would require submergences of from 400 to 1,400 feet; of the Lake-district a little deeper; while the distant dispersion of the Arenig boulders took place at sub mergences between 800 and 2,000 feet. The author describes MANCHESTER Literary and Philosophical Society, January 8.-Charles Bailey, F.L.S., in the chair.-Mr. Thomas Rogers read a paper on, and exhibited many specimens of, ballast plants collected at Cardiff in September, 1878. February 25.-E. W. Binney, F.R.S., in the chair.-On the mean temperatures of the winters of the last twenty-nine years, by the Rev. Thomas Mackereth, F.R.A.S., &c. March 4.-J. P. Joule, F.R.S., president, in the chair.-On a modification of Bunsen's calorimeter, by Prof. Balfour Stewart, LL.D., F.R.S.-The poisonous qualities of the yew, by William E. A. Axon, M.R.S.L., F.S.S. March 18.-J. P. Joule, F.R.S., president, in the chair.-On siliceous fossilisation, part 2, by J. B. Hannay, F.R.S.E., F.C.S., Assistant Lecturer on Chemistry in the Owens College. EDINBURGH Royal Society, March 17.-Prof. Kelland, president, in the This paper chair.-Sir William Thomson communicated a paper on vortex motion, gravitational oscillations in rotating water. contained an investigation of oscillations under the influence of gravity, of a mass of rotating liquid; former communications having been chiefly directed to the discovery of the vortex theory of atoms. In Laplace's great work on the theory of the gravitational oscillations of a mass of water spread over an approximately spherical body, he takes account of the fact that the earth is rotating and of the effects produced thereby on the motions of the ocean, and how these motions are affected by the tion due to the rotation of the earth affects the tides very congreat continents. Sir William Thomson finds that vortex mosiderably, even in such comparatively small areas as those of the He shows that in a English Channel and the North Sea. limited basin without an aperture, covering from, say, one to ten degrees of latitude, any tidal phenomenon which there may be, due to the gravitation attraction of the moon, is greatly affected by the rotation of the earth, if the greatest period of free oscillation of liquid in the basin is comparable with the period of rotation of the earth. It is to this fact that the peculiar phenomenon of the tides in the English Channel is due. The peculiarity is this, that for instance when it is high water at Dover, there is low water at the other end of the channel, and simultaneously a nodal line at St. Alban's Head, i.e., no rise or fall there; moreover, there are currents across this nodal line towards the end of the channel at which the tide is rising, i.e., water is flowing east across this line when tide is rising at Dover, and west when it is On rising at the other extremity. This phenomenon holds true only for ten or twenty miles on the English side of the Channel. the French side there is nothing of this kind but a gradual On the transition of the time of high tide along the coast. English coast, within a comparatively short distance, not more In than thirty miles, on either side of the nodal line referred to, there will be high tide on the east simultaneously with low tide on the west. He explains this by showing that in a canal of uniform breadth and depth, along which a wave is travelling, the effect of the rotation of the earth is to make the wave cling to the right hand side in whichever direction the wave is travelling. This manifests itself by the crest of the wave not being of equal amplitude all across the canal, but falling off from the right side down to nothing on the other side if the breadth of the canal is great enough. Where y is the distance of a point from the right bank and x the distance along the bank, the expression for the height of the crest is e sin (px - qt). a canal which has non-parallel sides, i.e., in which the sides converge, the effect is more marked. This is true of the English Channel or of any other where the time of an oscillation running across from one side to the other and back, is comparable with the period of rotation of the earth. He has worked out the problem in the case of the canal mentioned above, and also for forced and free oscillations in a circular basin.-The next paper was one by Dr. Joseph Coats, Dr. Wm. Ramsay, and Prof. McKendrick, on the action of anaesthetics on the blood pressure. The question they originally wished to solve was whether, in cases where the use of chloroform destroyed life, the result is due to its effect on the respiration or to the action on the heart. They found that at first sight it affected the respiration, but by keeping up artificial respiration they found that it also had an action upon the heart. They experimented both on rabbits and on dogs with the following results:-Chloroform and ethydene chloride reduce the blood pressure, while ether has no appreci. able effect. Chloroform reduces the blood pressure much more and much more rapidly than ethydene. It has also an apparently capricious effect on the heart's action, the blood pressure being reduced to nothing and pulsation being very rapid. Sometimes the heart's action was affected as much as a minute or more after the chloroform had ceased to be administered and after the blood pressure had recovered nearly its normal state. The effect of ethydene was to reduce gradually the blood pressure. Chloroform causes death in dogs primarily by paralysing either the heart's action or the respiration according to the individual's peculiarities. The respiration generally stops before the heart's action ceases. They found that artificial respiration was very effective in restoring animals in danger of dying from the effects of chloroform. Ethydene never produces absolute cessation either of the heart's action or of respiration. The results ob tained confirm and amplify those of the Committee of the Royal Medical Chirurgical Society of 1864.-Prof. McKendrick showed some experiments by Mr. Aitken on the physiological action of rotating disks on the retina.-Mr. Thomas Muir gave some general theorems on determinants, viz., an expression for the product of a determinant by one of its minors; a theorem for the reduction of the order of a determinant, another for [the multiplication of a determinant by an expression of a number of terms equal to the order of the determinant. He laid on the table a note on alterants. PARIS Academy of Sciences, April 7.-M. Daubrée in the chair. -The following papers were read:-On the iodides of stannpropyls, by M. Cahours.-On complementary pirouettes, by M. Chevreul. A disk having one half painted with colour a, and the other half white, and being rotated not more than 160 times a minute, nor less than 60, the complementary c of a appears on the white half.-Consequences of experiments made to imitate terrestrial fractures, with regard to various characters of exterior forms of the ground, by M. Daubrée. He points out several examples of the influence of diaclases and paraclases in determining the form of land, their directive influence on erosion, &c. -M. de Lesseps presented a brochure of the International African Association, containing a recent lecture by him, and a catalogue of African products at the recent exhibition.-The following elections were made :-M. Alphonse Milne Edwards, member in anatomy and zoology, in place of the late M. Gervais M. Abich, Correspondent in Mineralogy, in place of M. Damour, elected Free Academician; Mr. Lawes, correspondent in rural economy, in place of the late Marquis de Vibraye.-Analysis of the physiological action of sulphates of magnesia and soda, by M. Moreau. This describes an experiment wherein, some time after ingestion of magnesian sulphate into the intestine, he introduced yellow cyanide of potassium as a test of absorption. The urine afterwards showed no trace of cyanide. The sulphate causes afflux of liquid in the intestinal cavity; so that this occurred in ; the present case without manifest absorption.--On the summa. tion of a particular species of series, by M. André.-On displacements produced in the interior of an elastic ground by normal pressure exercised at a point of its surface, by M. Boussinesq.-Heat-centre produced by molecular shocks, by Mr. Crookes.-Reply to M. Flammarion's note on the declina. tion of the magnetic needle, by M. Marié-Davy. The reason of the alleged different action of the needle at Paris he finds in the dissimilarity of the methods employed in calculation of the averages grouped in M. Flammarion's tables.-On the gravivolu meter, by M. Houzeau. In this instrument liquid is forced up out of a vessel into a siphon by blowing through a caoutchouc tube, which is then closed with a spring pincer; on pressing the latter, air enters, and the liquid comes from the siphon drop by drop, with great regularity; the numeration of the drops gives precisely the weight of the liquid.-On determination of the presence of fire-damp in the atmosphere of mines, by MM. Mallard and Le Chatelier. They use a lit jet of hydrogen, which gives a larger and more distinct blue aureola than the flame of a common safety-lamp in presence of fire-damp, and reveals the presence of even o'25 per cent. of the latter gas. The flame, within a cylinder of copper, is viewed through a lens closing a lateral orifice.-On some conditions of alcoholic fermentation, by M. Richet. Oxygen renders more rapid lactic fermentation of milk. Boiling, by coagulating an albuminoid matter origin. ally soluble, diminishes by one-half the activity of the fermentation. Digestive juices which give soluble albumen and peptones increase the rapidity of lactic fermentation.-On the amylaceous and amyloid granules of the egg, by M. Dastre. He opposes M. Dareste's affirmation of the presence of amyloid bodies in eggs, maintaining that they are certainly not starch, and have not even the appearance of it.-Determination of sugar in the blood, by M. d'Arsonval. He defends a method of the late Claude Bernard's against recent objections by M. Cazeneuve.— On the method used by Claude Bernard for determination of reducing sugars in the blood, by M. Picard. If there are some animal substances which have the same action on cupric liquors as glucosic solutions, there are a very large number which have rotatory power.-On the distribution of phosphates in the different elements of the blood, by M. Jolly. Alkaline phosphates predominate in the aqueous part of the blood. All the elements contain a variable quantity of phosphate of iron, but it is chiefly accumulated in the corpuscles.-On the formation of a peculiar amyloid matter in the asci of some Pyrenomycetes, by M. Crié. What distinguishes this essentially is (1) its formation in profound darkness by a protoplasm without chlorophyll, and (2) its insolubility in the cellular liquids. This amyloid matter, the physiological rôle of which is not yet known, M. Crié calls amylomucine.-On ancient glaciers in the Maritime Alps, by M. Desor. THE RESULTS OF RECENT RESEARCHES IN ANIMAL ELECTRICITY. |