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Prof. A. Young described a remarkable case of an artesian well in the Karroo which shows a daily fluctuation in its discharge. The curve obtained during some weeks by a self-recording apparatus is very regular, and mas a period of almost exactly 12 hours. The ampliEude shows a marked variation, corresponding in time with the phases of the moon, and analogous to marine spring and neap tides. The outlet is more than 2700 feet above sea-level, and the author suggests that the water, which contains a large amount of inflammable gas, is forced up from a great depth through fissures by the pressure of natural gas, and that the observed fluctuation is a minor effect, due to the moon, superimposed on the effect of the constant gas-pressure. The phenomenon is scarcely affected by barometric changes.

At a joint meeting with the Geographical Section on the second day, Mr. H. C. Schunke-Hollway gave an accunt of the physical geography of Cape Colony. Mr. Rogers read a paper on Glacial periods in South Africa, in which he described the glacial deposits of Table Mountain Sandstone- (Silurian?) and of Dwyka- (Carboniferous) ge, each formed of materials derived from the north. There is no satisfactory evidence of glacial action in later times, the glaciated forms of certain hills in Griqualand West, cited by Stow, being now known to have been produced at any rate not later than Dwyka times, since similar forms may be traced underneath the surrounding Dwyka conglomerate. They have been preserved by a thick covering of Dwyka and other beds, which have only recently been removed.

Prof. A. Penck (Vienna) contributed a paper on changes of climate as shown by variations of the snow-line and upper tree-limit since Tertiary times, in which, from a nsideration of the geological evidence as to the relative hight of the snow-line and tree-line in Glacial times, he frew conclusions as to the cause of the glacial conctions. The facts pointed to a lowering of temperature as the cause of the glaciation rather than to an increase of precipitation. Prof. Penck suggested that an examination of the higher parts of the Drakensberg might probaly reveal traces of a Pleistocene Ice age in South Africa, though hitherto satisfactory evidence of this has been Wanting.

Prof. W. M. Davis, of Harvard, brought forward evidence for the sculpture of mountains by glaciers.' He based his arguments principally upon the marked differerce in form between valleys proved in other ways (e.g. by The presence of striations) to have been once glaciated, and those which have not been glaciated, the differences being in nature and distribution such as glaciers would Cause on the assumption that they could erode.

Papers were also read by Prof. Sollas, on the continent rf Africa in relation to the physical history of the earth; by Prof. J. Milne, on recent advances in seismology; by Mr. E. H. L. Schwarz, on “ Baviaan's Kloof, a Contribuon to the Study of Mountain Folds "; and by Mr. H. T. Ferrar, on the geology of South Victoria Land, giving 1 results of his observations on Antarctic rocks and aciers made during the voyage of the Discovery. Prof. Sollas sketched a possible way in which the present tribution of oceans and continents on the globe may hay arisen. The earth is not strictly a spheroid, but sembles an ellipsoid, of which the shortest axis passes hrough the poles, while the longest lies in the plane of he equator and emerges in Central Africa. The distribuion of land and water is such as would obtain if the arth had the form of a pear which had been somewhat ompressed in the direction of its core, and thereby caused bulge laterally. Africa would be situated on the broad d of the pear, and would represent the remains of the imeval continent-a supposition consistent with the hown absence of marine sediments over the greater part the interior, notwithstanding the thick accumulations flat-bedded strata existing there.

Mr. Schwarz's paper contained an account of a remarkle piece of geological structure observed in the valley of Baviaan's River, a tributary of the Gamtoos River, in e neighbourhood of Port Elizabeth. On the Baviaan's ver occur certain outliers of Enon conglomerate (CretaThe papers by Prof. Penck and Prof. Davis will be published shortly in Geographical Journal.

ceous) which have been found by bore-holes to occupy steepsided, basin-shaped depressions with no outlet, in Palæozoic rocks of the Bokkeveld and Witteberg series (Cape system). The basins are bounded by faults or steep dipslopes, and are explained as having been formed by two series of cross-foldings trending E.S.E. to W.N.W. and N.E. to S.W., which took place while the country was covered with the Enon conglomerate, the latter being faulted down upwards of 1000 feet. The author objects to the usual explanation of rock-folding as produced by a direct tangential thrust against an obstacle, caused by shrinkage of the earth's crust, and suggests that it may in

fact be gradually produced by earthquake-waves travelling through one kind of rock (say sedimentary beds resting on granite) and encountering a mass of rock having a different modulus of elasticity (as, for example, a boss of the underlying granite). The effect of this would be to heap up the strata in folds against the obstacle, somewhat as when waves break on the shore.

At Johannesburg a considerable number of the papers were, appropriately, of mineralogical and petrographical interest.

The proceedings opened with the delivery of the presidential address by Prof. Miers (NATURE, August 24, vol. Ixxii. p. 405).

Prof. J. W. Gregory followed with two papers of special interest to gold miners. In one of these, on the Rhodesian Banket, he stated that he had found during a recent examination of the district that the name had been applied to several different rocks which are locally auriferousnot only to an undoubtedly sedimentary conglomerate forming the main mass of the material, but also to crushconglomerates and breccias, and to a diorite dyke with segregations of amphibolite. The Rhodesian conglomerate may probably be rightly called Banket, but differs considerably from the Banket of the Rand in its fluviatile origin, the greater variety in size and composition of the pebbles, and its probably greater age. The question as to the right of the Rhodesian deposit to the name of Banket aroused considerable discussion.

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In his second paper (on the Indicators of the goldfield of Ballarat-a study in the formation of gold pockets) Prof. Gregory showed the secondary origin of the so-called indicators, or thin iron-stained bands, which traverse the slaty country-rock of Ballarat and lead to rich pockets of gold at the points where they intersect the otherwise barren quartz reefs. The indicators are shown by microscopic and field evidence to be narrow seams of chlorite or rutile needles, which are not quite, though, as a rule, nearly, parallel to the bedding, and cannot therefore be of sedimentary origin.

Prof. R. Beck, of Freiberg, gave a summary of recent investigations on the origin of pegmatites as products of the crystallisation of the residual mother liquors of a solidified plutonic magma. Certain ore-veins have been formed thus as metalliferous pegmatites, for example the tin veins of Zinnwald and Embabaan, the copper ores of Telemarken and the auriferous quartz-reefs of Berezowsk, the Yukon district and Passagem, and other places in Brazil. The presence of tourmaline in certain gold-quartzes bears out this view of their origin.

Prof. A. P. Coleman, of Toronto, dealt with the magmatic segregation of sulphide ores. The recent complete mapping of the eruptive sheet with which the nickel-ore deposits of Sudbury (Ontario) are all connected, shows that the Sudbury ore is, like the pyrrhotite nickel ores of Norway described by Vogt, really a product of segregation from the rock, of which it forms an integral part with every gradation between ore and rock. Gravitation has probably played a large part in the segregation process.

Prof. Grenville A. J. Cole read a paper on marginal phenomena of granite domes, in which he upheld the view that banded gneissic rocks are due rather to the incorporation of the surrounding rocks with the materials of an invading granite than to simple dynamic metamorphism; the banding is produced by igneous flow, and is especially marked in cases where the absorbed rocks were sedimentary or already foliated.

On the second day Mr. G. W. Lamplugh gave his report of a journey, made under the auspices of the association to examine the zigzag gorge of the Zambesi

below the Victoria Falls, from which he had just returned. Mr. Lamplugh, who penetrated down stream for a distance of 70 miles from the Falls, accepts and confirms the explanation given by Mr. Molyneux, of Bulawayo, who attributes the zigzags to the guidance of the stream-erosion by transverse joints in the basalt plateau through which the gorge has been cut.

Prof. Penck read a paper, illustrated by a fine series of lantern slides, on the Glacial deposits of the Alps.

Mr. Kynaston, director of the Geological Survey of the Transvaal, gave an account of the recent work of the survey. Since its re-organisation in 1903, the attention of the survey has been chiefly occupied with the later formations forming the central portion of the country, and the results obtained bear testimony to the able way in which the work has been carried on. The igneous complex of the Bushveld to the north of Pretoria may be mentioned as forming an interesting petrographical province. illustrates the differentiation of a magma, in what is probably an enormous laccolite, intruded between the Pretoria and Waterberg series, into zones of increasing basicity, ranging from the red granite of the central region to the norites, pyroxenites, serpentine, and magnetiterock of the margin.

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Dr. F. H. Hatch explained the views arrived at by Dr. Corstorphine and himself as to the correlation between the pre-Karroo beds of the Transvaal and those of Cape Colony ("Geology of South Africa, 1905). Dr. Hatch also exhibited an instrument, devised by Mr. Oehmen, for surveying bore-holes, that is, for determining the amount and direction of the inclination of the bore-hole to the vertical at any given depth-a problem of considerable importance in a country where diamond drilling is so largely used as in South Africa, as a deep bore-hole may deviate as much as 30° or more in its lower levels.

The Rev. S. S. Dornan gave an account of his observations on the geology of Basutoland. The rocks belong to the Stormberg series, and consist of sandstones, mudstones, and shales forming the Molteno Beds and the overlying "Red Beds." Fossils are rare, but a few plant and reptile remains have been found in the former. Above the Red Beds lies the Cave Sandstone, a thick-bedded sandstone, which forms the crests of the hills and contains caves sometimes showing Bushman paintings. Reptile tracks are frequent, but few other fossils occur. The higher ridges of the Drakensberg and Maluti ranges are formed of lava-flows and intrusive sheets belonging to the volcanic series. This communication was of special interest on account of the difficulty of making observations and collecting fossils in Basutoland, as it is a native reserve, and the natives are unwilling to allow any prospecting, fearing lest they might lose their country should gold be discovered.

On the last day of the meeting Mr. C. B. Horwood read a description of the Dolomite formation, which is important as being practically the only source of underground water supply in the Transvaal. The rock is probably a deep-sea deposit, which has subsequently undergone dolomitisation in shallow water, and has lost in the process all trace of organic remains, so that its age is unknown. Mr. W. Anderson contributed a paper describing the first Tertiary rocks of marine origin which have been discovered in South Africa. These comprise sands, marls, and shales, with marine Mollusca (identified as probably of Eocene age) and Foraminifera in the upper beds, while in the lowermost shales occur numerous isolated bones of Mammalia (elephant, rhinoceros, hippopotamus, &c.), with water-worn fragments of fossil wood, and fish and crustacean remains. The beds, which are confined to the coast of Natal and Zululand, are probably of estuarine origin. A calcareous grit, forming the Bluff at Durban, is also probably Tertiary in age.

A paper by Mr. E. T. Mellor dealt with the evidences in the Transvaal of glacial conditions in Permo-Carboniferous times, and the distribution of the glacial conglomerates forming the base of the Karroo system, which corresponds to the Dwyka conglomerate of Cape Colony. Here, as in the country to the south, the striations, as well as the nature of the boulders, point to a northerly origin. Mr. Lamplugh read a note on the occurrence of Dwyka conglomerate at Kimberley Mine.

In a paper on the diamond pipes and fissures of South Africa, Mr. H. S. Harger expressed his view that the source of the diamond lav in a zone of ultra-basic rocks -eclogites, lherzolites, and pyroxenites-in which it may be an original constituent crystallising from the magma, for it has been frequently found in garnets and more rarely in olivine, and has been produced artificially in the latter. The blue ground filling the diamond pipes and the associated fissures is an altered breccia formed by the shattering of these ultra-basic diamondiferous rocks during a period of volcanic activity, probably in late Triassic or Jurassic times. Mr. Harger's paper was especially valuable as embodying the results of careful personal observations carried on through several years on the occurrence and associations of the diamond in the numerous mines scattered up and down the country, some of which are little known outside South Africa. An interesting collection of specimens of the associated minerals was on exhibition in the adjoining museum.

Papers were also communicated to the meeting by Dr. J. T. Carrick, on the geology of the West Rand; by Mr. F. P. Mennell, on the plutonic rocks and their relations to the crystalline schists; and by Mr. E. Heneage, on a consideration of the Archæan period of North America and South Africa with reference to mineral occurrences.

Apart from the papers read, a more than usual amount of interest attached this year to the geological excursions, of which a large and most interesting series were organised by Dr. Mclengraaff, Prof. R. B. Young, and Mr. Rogers, to whom, with the other gentlemen who acted as leaders, the thanks of the section are especially due. These excursions--many of which occupied several days and were on a scale hitherto unprecedented, except possibly at the Toronto meeting in 1897-afforded the members of the Geological Section a unique opportunity of seeing the most interesting features of the Country under the guidance of the men by whom they had been investigated, members of the various surveys being spared for the purpose by their respective Governments.

After the meeting at Cape Town Mr. Rogers led a party through the Karroo, visiting, among much else of interest. the folded ranges of the Hex River district, and exposures of the Dwyka conglomerate (or Boulder-clay) and of the Beaufort beds which have vielded Pareiasaurus and other characteristic reptiles. While in Natal, several members visited the glaciated surfaces and overlying beds at Vryheid, under the guidance of Mr. W. Anderson, the Government geologist, and Dr. Molengraaff, formerly State geologist of the Transvaal. During the meeting in Johannesburg a number of afternoon excursions were made to the gold mines and other points of interest, while after its conclusion several more extended expeditions took place. These included one to Vereeniging, under Dr. Hatch, to examine the sandstones and coal-seams of the Ecca series, which have yielded the Glossopteris flora, and the associated beds, and to see Mr. T. N. Leslie's collections of fossil plants from the Ecca sandstone and of flint implements from the Vaal River. Another party had an oppor tunity of studying the norites and syenites of the Plutonic complex of the Bushveld, at the Pyramids and in the neighbourhood of the Pienaar's River, to the north of Pretoria, under Mr. Kynaston and Mr. A. L. Hall; while a third party, with Mr. Hall and Mr. Frames, visited the Duivels Kantoor, at the eastern edge of the Transvaal plateau, where the escarpment of the Black Reef series and Dolomite overlooks the floor of Archæan rocks, on the denuded surface of which they rest unconformably.

Excellent opportunities were also afforded of studying the occurrence of the diamond, both at the Premier and other Transvaal mines, under Mr. Cullinan, the chairman of the Premier Diamond Company, and Messrs. Hall Harger, Kynaston, and Trevor, and at Kimberley through the kind offices of Mr. Gardner Williams, the chairman of De Beers.

In addition to this, there was a great deal of interest t the student of surface geology to be seen during the long train journey, among which may be mentioned the hill country in the north of Natal, the flat and sandy bush scenery along the line to the north, and the wonderful examples of weathering in the granite country of the Matopo Hills.

UNIVERSITY AND EDUCATIONAL

INTELLIGENCE.

OXFORD.-Dr. Haldane, Fellow of New College, has been re-appointed lecturer in physiclcgy on the nomination the Waynflete professor. The appointment is for three sears from January 1, 1906. Chemical physiology is the particular subject assigned to the lecturer.

The degree of M.A. has been conferred, by a decree of Convocation, on Dr. Schlich, secretary to the delegacy for superintending the instruction of Indian forestry

students.

CAMFRIDGE.-An election to an Isaac Newton studentship all be held in the Lent term, 1906. These studentships or for the encouragement of study and research in astrorony (especially gravitational astronomy, but including cher branches of astronomy and astronomical physics) and prisal optics. The studentship will be tenable for the erad three years from April 15, 1906. The emolument

the student will be 200l. per annum. Candidates for the studentship are invited to send in their applications toth: Vice-Chancellor between January 16 and 26, 1906, gether with testimonials and such other evidence as to their qualifications and their proposed course of study or research as they may think fit.

An appointment to the Anthony Wilkin studentship in ethnology and archæology (Reporter, May 23, pp. 920-1) will be made in January, 1906. Applicants should send in cer names, qualifications, and a statement of the research which they wish to undertake, to the Vice-Chancellor before January 1, 1900.

Mr. T. S. P. Strangeways, of St. John's College, has been re-appointed demonstrator of pathology for a period five years from Michaelmas, 1905.

Prf. C. S. Sherrington, F.R.S., and Prof. R. Threlfall, FR.S., have been elected honorary fellows at Gonville and Culus College.

I State Medicine Syndicate has nominated Mr. J. E. Purvis, Mr. G. H. F. Nuttall, Dr. J. Lane Notter, Dr. R. D. Sweeting, and Dr. A. Newsholme to be examiners in State medicine in the year 1905; and Mr. G. H. F. Nuttall, Mr. C. W. Daniels, and Prof. Ronald Ross, C.B., F.R.S., to be examiners for the diploma in tropical edicine and hygiene in the year 1905.

Dr. W. A. BONE, F.R.S., has been appointed professor plied chemistry (fuel and metallurgy) in the University Leds.

MR CHARLES W. E. LEIGH, formerly of the Natural History Museum, South Kensington, and late assistant Scary and librarian to the Manchester Literary and Filosophical Society, has been appointed librarian of the University of Manchester.

THE following appointments, Science states, have been mace in the faculties of the George Washington UniSt-General Henry L. Abbott, U.S.A., to be proof hydraulic engineering; Dr. Edward B. Rosa to professor of physics; and Brigadier-General George M. berg, U.S.A., to be professor of preventive medicine. WE learn from Science that President Eliot, of Harvard Unversity, has received a letter from President Pritchett, the Massachusetts Institute of Technology, communiing the fact that, in view of the recent decision of the Spreme Court of the State in the case of John Wilson cthers v. the Massachusetts Institute of Technology, The corporation of the institute find it impossible to proceed h the plan of cooperation between the university and the institute which has been under consideration for the past six months. The committee appointed by the Harvard ard at the request of the institute has consequently been rischarged.

Ar the annual general meeting of members of the Bedfrd College for Women, held on November 17, the chairan, the Right Hon. A. H. Dyke Acland, announced that the Parliamentary grant to Bedford College had for the Current session been increased from 2000l. to 4000l. It was also reported that past students had already contributed 3500l. to the building fund. Principal T. G. Foster, of University College, and Lady Lockyer have been NO. 1882, VOL

elected members of the council, as representatives of the senate of the University of London. The council offers two open scholarships of the value of 20l. each for one year for the course of secondary training beginning in January, 1906. The scholarships will be awarded to the best candidates holding a degree or equivalent in arts or science. Applications should reach the head of the training department not later than Monday, December 18.

SIR W. H. PREECE distributed the prizes and certificates to the students of Birkbeck College on November 14, and afterwards delivered an address on the simplicity of science. Sir William Preece said he has never believed that in scientific and technical training Englishmen are far behind the rest of the world. However lacking we may have been in the upper regions of higher education, we have never failed to encourage education in other ranges, and Birkbeck College was one of the first in this country to spread the love of science and to offer educational facilities to those willing to use them in their leisure hours. What is wanted now, he continued, is that men who make fortunes in the metropolis shall become patriotic founders of endowments for enabling us to distribute the teaching advantages already existing to all classes of society. Sir W. Preece incidentally remarked on the absence of memorials to pioneers of science, mentioning especially Sir Henry Bessemer-an old student of Birkbeck College. Towards the conclusion of his address he suggested that Members of Parliament, before being permitted to legislate, should have to go through a course of instruction in scientific modes of thought.

Ar a dinner given by the Society of Apothecaries on November 14. Mr. John Tweedy, president of the Royal College of Surgeons, responding to the toast The Royal Colleges of Physicians and Surgeons, dealt with the subject of medical education. He said that, in accordance with the promptings of the General Medical Council, the Royal College of Surgeons has raised the standard of general education of medical students, and has increased the multiplicity and severity of the examinations. But Mr. Tweedy would like to see the wheel turned back a little. He thinks that too much is being attempted in the way of examinations, and desires to see steps taken in the direction of simplification, without any sacrifice of efficiency. If some of the restrictions and regulations were relaxed, he believes a better class of practitioner than is possible under the present régime could be produced. The student is over-taught, over-examined, so that he has no time to reflect, to exercise his reason or his intellect. Mr. Tweedy believes that the medical examinations are best entrusted to professional corporations. Although he does not go so far as to advocate deprivation of the universities' power of granting qualifying degrees, he pointed out that the universities do not possess a qualifying degree in law.

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Royal Society, July 29.-"Studies on Enzyme Action. VII. The Synthetic Action of Acids contrasted with that of Enzymes. Synthesis of Maltose and Isomaltose. By E. Frankland Armstrong. Communicated by Prof. H. E. Armstrong.

The belief has grown up of late years that the enzymes which are capable of inducing the hydrolysis of disaccharides or bioses act reversibly; as yet, however, but little has been done to define the theory of the process, and no understanding has been arrived at as to the limitations to which such changes are subject. The same is true of the action of acids, which also act reversibly under certain conditions.

The key to the interpretation of the changes which attend condensation must be looked for in the behaviour of glucose itself in solution.

The term glucose, in fact, has a double connotation, and these two substances must usually be thought of under the single name. As crystallised from alcohol, it consists almost entirely of the a-form; but this changes over into the B-form if maintained during several days at about 105°. If either form be dissolved in water, change takes place of the one into the other; ultimately, the two forms

exist in sclution in equilibrium, in proportions which depend on the conditions, the B-compound predominating. Change takes place in a similar manner in other media.

The process by which a monose is converted into a biose must be regarded as precisely similar to that by which a-glucose and B-glucose are converted into the two methylglucosides the behaviour of maltose, in fact, is such as to characterise it unquestionably as glucose-a-glucoside; isomaltose is presumably the stereoisomeric glucose-8glucoside.

When glucose undergoes condensation

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uncontrolled,"

it should give rise to both maltose and iscmaltose, the proportions of which ultimately present in equilibrium would depend on their relative stability under the conditions operative at the time. But, inasmuch as hydrolysis under the influence of enzymes is an absclutely selective process, being so controlled that it takes place in one direction only, it might be supposed that synthesis under their influence would also be a controlled operation, and that the tendency of the enzyme would be to reproduce the bicse which it hydrolyses apparently this point of view was present in Croft Hill's mind and led him to suppose, at first, that maltose was the actual product; as a matter of fact, it is uncertain at present whether maltose is produced at all: it is certainly not the sole or the predominant product.

even

The formation under the influence of the enzyme of a single biose, isomeric with that which it hydrolyses, could be accounted for on the assumption that both are produced initially, but that the one again undergces hydrolysis as soon as it is formed, so that it all but disappears.

Proof is given in the present communication that when the condensation is effected under laboratory conditions the action takes place in the manner indicated above; in other words, the two products required by thecry are both formed. Evidence is adduced to show that isomaltose is the B-glucoside correlative with the a-glucoside maltose. Experiments are described bearing on the formation of isomaltose by the agency of the a-enzyme maltase and of its correlative maltose by the agency of the B-enzyme emulsin which leave little doubt that the two bioses are producible from glucose. Whilst it is left undecided whether maltase can give rise to maltose, evidence is cited which at least renders it probable that emulsin does not give rise to isomaltose.

"Studies on Enzyme Action.-Lipase." By Herry E. Armstrong, F.R.S.

The study of vegetable lipase is of special importance, as the ordinary fats-which are hydrolysed under its influence with peculiar readiness-are not asymmetric material but simply glycerides of acids of the acetic or oleic series. The interest of the inquiry is enhanced by the fact that animal lipase, according to Dakin, acts selectively but the selective effect of lipase is of a different order from that displayed, for example, by an enzyme of the sucroclastic class, which can only attack one member of a pair of enantiomorphous isomerides.

In the course of the experiments, Connstein's contention has been confirmed that the presence of acid is necessary to condition the hydrolysis and that practically any acid is effective provided a sufficient amount be used. Aspartic and glutamic acids-which are formed at an early stage of the germination of seeds-were found to be highly active; glycin and asparagin, however, were practically without effect.

All attempts resulted in failure which were made to obtain an extract containing an enzyme, whether from the freshly-ground material directly or after this had been deprived of the fatty matter and whether or no acid were present. Apparently, acids do not act merely by liberating the enzyme.

The Ricinus enzyme has been found to have but little action, not only on ethylic butyrate, on acetin and on dimethylic tartrate and racemate but also on ethylic mandelate, which, according to Dakin, is readily attacked by animal lipase.

It is difficult to resist the impression that the differences observed are not merely consequences of differences in stability of the various ethereal salts but that the Ricinus enzyme is possessed of properties which ake it specifically

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ture.

After the contradictory experiments of Müller-Hettlingen, and Elfving, Brünchorst found that strong currents produced a positive, and weak currents a negative, curvaRoots hence appeared to possess a parallelotropic irritability to electrical currents, reversible according to the intensity, as in the case of heliotactic and heliotropi irritability. The experiments were not altogether satis factory, nor did they reveal the mode of stimulation, su further investigations seemed desirable.

These have shown that the curvatures are produced by the acid and alkaline products of electrolysis liberated on opposite sides of the root. The acid products are mor effective than the alkaline, so that when the current is led transversely through the subapical sensitive region the curvature always takes place towards the positive electrode; but if one electrode is placed upon the hypocotyl and the other on the irritable zone, the curvature is always towards the latter electrode, whether it be positive cr negative. These galvanogenic curvatures are hence chemotropic in origin, as has been shown by direct experiments with acids and alkalis. Thus, if the rects are imbedded at varying distances in gelatin through which a Current is passed, the roots curve in regular order towards the electrodes shortly after the acid or alkali, as evidenced by phenolphthalein, has diffused near to them.

In addition, the application of the electrolysed region of a root or of filter paper moistened with decinormal acid or alkali produces similar curvatures.

All these curvatures have been produced on a klinostat and without any injury to the root. Indeed, in many case a constant current of 0-000009 of an ampere is sufficient to cause a curvature. Using non-polarisable electrodes, no response is given unless very strong currents are used. since the stimulation is now dependent upon the restricted internal polarisation in the root.

It is doubtful whether the electrical currents in the soil call this special irritability regularly into play. The power of curving towards faintly acid cr alkaline regions must aid the root greatly in reaching soil where soluble con stituents are most likely to be abundant, or where anaerobic nitrogenous decomposition (with a production of ammonia) or the subsequent aërobic nitrification (with a production of traces of nitrous and nitric acids) are ir progress.

The non-development of any power of curving away from strong acid or alkali is to be explained by the non occurrence of high local concentrations in normal soil Even when a strong local acidity or alkalinity is artificially produced in the soil, the roots are killed before they car curve away from it, and even if the apical zone did curve away, the non-curving zone behind would be rapidly killed.

Sociolo ical Society, October 24.-Sir John Cockburn in the chair.-Biological foundations of sociology: Dr. G Archdall Reid. The author outlined modern teaching on the subject of heredity, accepting the Weissmannian con clusion regarding the non-inheritance of acquired characters. These principles he applied to human qualities with especial reference to the possibilities of selective breeding. Four main conclusions were reached :-(a) That there is a confusion, in popular and in uncritical medical opinion, of variation with acquirement. Many individual acquirements are considered innate. (b) That racial

ange through heredity is a process requiring very long
riods of time, so increase of natural ability by selection
variations must remain, on the whole, inconsiderable.
That the more important factor is individual acquire-
ent or education. The great output of genius during
Athenian and Renaissance periods is to be explained,
t in terms of natural ability, but as arising from ex-
ptional opportunity. (d) That the one practicable method
improving the racial average of natural ability is by
dimination of clearly degenerate types.

Challenger Society, October 25.-Mr. F. W. L. Holt
the chair.-Charts illustrating the physical conditions
the English Channel during 1903 and 1904: Dr. E. J.
llen and D. J. Matthews. The observations, which
ere conducted from the Plymouth laboratory of the
farine Biological Association as a centre, had been made
y the association's steamers Huxley and Oithona, by
cean-going liners and cross-Channel steamers, and
ightships and lighthouses. They extended from about
Jungeness to Cape Finisterre, and showed the north-
asterly movement of oceanic water of high salinity and
emperature, the southerly movement of water of low,
alinity from the Irish Sea, and the varying effects of
nese movements on the waters of the English Channel in
Efferent months.

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Royal Astronomical Society, November 10.-Mr. W. II. aw, president, in the chair.-Observations of the sixth d seventh satellites of Jupiter, from photographs taken the Royal Observatory, Greenwich, with the 30-inch flector of the Thompson equatorial: Astronomer Royal. The photographs were shown on the screen, with diagrams illustrate the crbits of the satellites.-Observations of e satellite of Neptune, from photographs taken at the oyal Observatory, Greenwich, with the 26-inch refractor : stronomer Royal.-Expedition to Vinaroz, on the east ast of Spain, to observe the total solar eclipse of August st: Father Cortie.-Eclipse expedition to Burgos: Mr. hwaites.-Eclipse expedition to Labrador: Mr. aunder. Photograph of the partial phase of the recent lipse showing distinctly the entire disc of the moon: Ir. Saunder. (1) Secular acceleration of the earth's rbital motion; (2) Ptolemaic eclipses of the moon corded in the Almagest: Mr. Cowell. In a paper already rinted the author showed that the ancient sclar eclipses re satisfied by adopting the following secular terms:in the distance of the moon from the node +4"-4, and 1 in the distance of the moon from the sun +6"-8. He w showed that these conclusions are supported by the lipses of the moon as given in the Almagest. Mr. Cowell rsidered that a secular acceleration of the earth's orbital tion does not contravene gravitational theory, as Prof. womb had suggested, since it might be ascribed to the sistance of the ether.-Other papers were taken as read. Physical Society, Noven ber 10.-Dr. C. Chree, F.R.S., ce-president, in the chair.-The question of temperature d efficiency of thermal radiation: J. Swinburne. ng been known that various surfaces have different nissivities, and it is generally held that at a given mperature some bodies radiate a larger percentage of eir total radiation in the form of light. This view is rgely based on some experiments by Evans and ttomley, both of whom, the author remarks, make the slip in confusing difference of emissivity with differre of efficiency at the same temperature. It is urged it a body A at the same temperature as B cannot give radiation corresponding to a higher temperature of B, if it could, and A and B were enclosed in a perfectly Jecting space, A would heat B to a higher temperature n A.-Note on constant-deviation prisms: T. H. kesley. It appears that any prism of three faces can made to give a spectrum in which the light, that upies the centre of the field of view of the telescope at moment, has undergone passage through the acting surfaces of the prism in such a way that its ginal angle of incidence is equal to its final angle of rgence. This condition, which in the ordinary employt of the prism is associated with minimum deviation, st be described as isogonal passage, the property which the minimum value being not the deviation, but the NO. 1882, VOL. 73]

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rate of passage across the field of view for a given motion of the prism, to which alone in these instruments motion has to be given to bring different parts of the spectrum into the field, the telescope and cellimator both remaining fixed. If any triangle having the angles a, B, y is adopted as the shape of a prism, the telescope must be set to make one of these angles, say y, with the line of the collimator. Then the pris.n being placed in the region between them, a position can be found so that any ray selected will be refracted through one of the sides containing the angle 7, reflected at the side opposite y, and finally refracted through the remaining side containing y On emergence it will be parallel to the telescope, and its passage through the refracting faces will be iscgonal. The prism will affect the light to the same degree as one used in the ordinary way, of refracting angle -a, would do. The sine of the angle of original incidence is equal to u. sin (B-a)/2 for every ray occupying the centre of the feld of view. If the prism is turned over, but the same angle employed, the telescope will remain unaltered, but the spectrum will run in an opposite direction to the first. Mr. Blakesley showed the case of two prisms in which the spectra ran in different directions. The top prism was slightly tilted by the insertion of a small piece of silver paper between the prisms. By this means I one of the spectra was shifted upwards by a small amount, and one could see in the telescope a band, at top and bottom, of the component colours, and in the centre a band of the resulting colours. It was suggested that spectroscopes on this plan could be advantageously employed in measuring the motion in the line of sight of heavenly bodies, as a line brought into coincidence with itself for a terrestrial source in the two spectra would, in the case of such motion, split up into two moving different ways in the field of view. It was also explained how such prisms could be placed in trains for increased dispersion.

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Royal Meteorological Society, November 15.-Mr. Richard Bentley, president, in the chair.--The rainstorm of August 24 to 26 in counties Dublin and Wicklow : Sir John W. Moore. The atmospheric disturbance which caused the torrential rainfall was near the shores of Kerry and Cornwall on August 24, and the next morning it was near the Scilly Islands. Thence it travelled slowly northwards up St. George's Channel, its centre passing near Dublin early on the morning of August 26. At this time the system suddenly changed its course, crossing the channel eastwards to Wales, and finally passing over central England and out to sea at the mouth of the Humber in a north-easterly direction. It appears that the rainfall on August 25 exceeded 3 inches at all stations in the counties Dublin and Wicklow, while it rose above 4 inches, and even 5 inches, at stations near the Dublin and Wicklow mountains. Sir John Moore is of opinion that this remarkable downpour was brought about by the cooperation of the following factors :-(1) a chill antecedent to the arrival of the rain-bearing depression; (2) the slow progress of the depression; (3) the fact that the counties Wicklow and Dublin lay to the westward of the cyclonic centre, and so received its north-easterly and northerly winds; and (4) the physical configuration of those counties and their coast line. As the result of this remarkable rainstorm a destructive flood occurred over the low-lying parts of the Bray urban district near the mouth of the Bray River. At Little Bray the water rose to a height of 4 feet in the streets, flooding houses, destroying domestic animals and fowls, wrecking furniture, and covering floors, yards, and gardens with a thick alluvial deposit.-The aquameter : Dr. W. B. Newton. This is a new instrument for measuring accurately the amount of aqueous vapour present in the atmosphere.

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Academy of Sciences, November 13-M. Troost in the chair.-Nitrates and nitrites as manure: Th. Schlæsing, jun. Nitrate of calcium is now produced by electrical means from the air, and the salt thus obtained contains nitrite. It was desirable to ascertain whether the calcium nitrate is equivalent for manurial purposes to the sodium nitrate in crdinary use, and also whether the nitrite was in any way prejudicial. Cultivation experiments showed that the two nitrates were equivalent, and that the presence

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