National Union of Scientific Workers. THE proceedings at the annual Council meeting of the National Union of Scientific Workers, held at the Imperial College of Science on January 26, tre enlivened by a spirited discussion on the position f the general secretary, Major A. G. Church, now hat he has been elected member of Parliament for Leyton (East). The suggestion was made that his ersonal association with a political party might give he Union a political complexion, but the majority f the representatives present were evidently of the pinion that the more scientific workers there were Parliament, irrespective of party, the more likeliood there would be of science exercising its proper fluence in national affairs. Mr. F. T. Brooks (Cambridge), in presenting the Exth annual report, emphasised the need for more ropaganda among leaders of industry and public odies in order that the importance of science to the ation should be more fully appreciated. During he year, a number of public meetings were arranged a different centres of industry, presided over by epresentatives of Chambers of Commerce and other ublic men. A questionnaire had been addressed to l members of the last Parliament with the view of scertaining their attitude towards research and the ublic endowment of research institutions, and an er had been made to certain industrial undertakings O put at their disposal the services of the Research ouncil, with the view of their making proposals for e proper utilisation of science in their industries. he fact is fully appreciated by the Executive of he Union that upon fuller recognition of the otentialities of science depends the welfare of the ientific workers who are being turned out from our niversities yearly. It is hoped that the prominence iven to this question at the forthcoming British mpire Exhibition at Wembley through the efforts CONSIDERABLE of the British Science Guild will have far-reaching effects. For the past two years at least, the claims made by the Union to the Treasury and other Government departments for the improvement of the salaries and conditions of service of scientific workers in Government departments have been weakened by the prevailing conditions of scientific workers in industry and in the universities. The attitude of the administrative heads of departments is demonstrated in the terms of the report of the committee on the pay of State servants. In this report it is stated that while the salaries of administrative officers cannot be based upon those which can be obtained by men of similar standing in outside professions, those of the scientific and technical officers were rightly based upon the current market rates. The Union will continue to press for a new inquiry into the position of civil servants engaged in scientific and technical work, and the setting up of the new Civil Service National Whitley Council, representation on both sides of which shall be confined mainly to scientific and technical officers. On the existing National Whitley Council, science has practically no voice, and to this fact can be attributed the want of success which has attended the efforts of the Union to obtain any measure of justice or equity of treatment. Dame Helen Gwynne-Vaughan, the retiring president, in her address dealt with the need for a federation of scientific bodies with the view of the ultimate creation of a General Scientific Council similar to that of the General Medical Council; this would lead to the ideal of science as a self-governing profession. Prof. G. H. Hardy, of Oxford, was elected president of the Union for the ensuing year, while Dr. J. W. Evans was unanimously elected president of the Research Council. Orographical Compensation in Northern India. discussion has arisen in recent years regarding the precise meaning of e gravity variations revealed by the geodetic survey I India. The Himalayan region and bordering ains in the foreground, which are of special interest ecause of Archdeacon Pratt's mathematical developent of the theory of mountain compensation, have rmed the subject of revived discussion on account the novel suggestion of subterranean rifting, made v Sir Sidney Burrard and his colleagues of the dian Trigonometrical Survey and criticised by Mr. . D. Oldham and the late Sir Henry Hayden of the eological Survey. The geologists considered that sufficient allowance had been made for the low -nsity of the large mass of alluvium in the foreground, ed an analysis of the data by Mr. R. D. Öldham lem. Geol. Surv. Ind., xlii., part 2, 1917) developed is aspect of the question as a partial explanation the observed deficiency in gravity. Since 1917, rther data have been published by the Survey ficers and by Prof. A. Alessio as the result of the lippi expedition to Central Asia. These results ve been examined by Mr. R. D. Oldham in a per recently published in the Records of the ological Survey of India (vol. lv., part 1, 1923), d he concludes that the fuller observations now ailable confirm the conclusions given in his previous emoir. In one of the professional papers of the Survey of dia (No. 18, 1921) Col. H. McCowie criticised Mr. dham's method of computation from an "imaginary range," but the method adopted was the only one possible without an organised computing staff with full topographical data, and the adoption of a simplified topography was frankly for the purpose of obtaining a sufficient approximation in results to estimate the relative values of the alternative theories. Other methods which have been criticised were similarly adopted in the absence at the time of data for a sufficient number of stations, and these, having now been supplied, permit of more precise computations being made. Along the outer Himalaya there is a zone of superelevation where the defect of density, or compensation, corresponds to a lesser altitude than that of the surface, and along a parallel zone at the foot of the hills there is a region of over-depression of the surface, and consequently excessive deficiency of gravity. These two conditions, according to Mr. Oldham, can be sufficiently explained, when allowances are made for the rock densities, by assuming for the earth's crust a degree of rigidity which prevents it from taking up immediately and fully the flexures which followed the Himalayan uplift and coincident Gangetic depression. A bye-product of Mr. Oldham's original line of argument was his conclusion that the excess of mass in the outer Himalayas would not continue over the whole range, but would disappear into the interior, and the results obtained during the course of the Filippi expedition to Central Asia seem to show that this is so. University and Educational Intelligence. CAMBRIDGE. The University of Cambridge Commissioners have authorised and directed the University to limit to December 31, 1925, the tenure of all officers appointed after the present date, except where the person before election shall have undertaken to hold the appointment subject to conditions that may be made or approved by the Commissioners. An offer of 5000l. has been made to the University by Mrs. Pinsent, Sir Francis and the Hon. Lady Darwin for the purpose of promoting research, by studentship or otherwise, into any problem which may have a bearing on mental defects, diseases, or disorders. In the letter in which the offer is made, the donors express the belief that the racial and social problems involved by the existence of such large numbers of mentally incapable persons in the community are of great national importance, and that their solution may have far-reaching effects. The gift is made in memory of Hume C. Pinsent, scholar and fellow of St. John's College; Erasmus Darwin, exhibitioner of Trinity College; David Hume Pinsent, scholar of Trinity College; and of Richard Parker Pinsent, exhibitioner of Balliol College, Oxford. Mr. T. T. Barnard, research student of King's College, has been elected to the Anthony Wilkin studentship for research in ethnology and archæology in Southern Sumatra; Mr. R. A. Webb, research student of Gonville and Caius College, to the Charles Abercrombie Smith research studentship at Peterhouse. The Army Council has asked the University if it would be willing to undertake the examination qualifying Royal Engineer officers to receive engineer pay. In view of the prominent part which the Department of Engineering takes in the training of Royal Engineer officers, the Special Board of Engineering Studies recommends that the University should undertake this work. LONDON. Dr. A. W. Porter has been appointed as from August 1, 1923, to the University chair of physics tenable at University College. Prof. Porter has been a lecturer and assistant professor at University College, and, since 1913, University reader in thermodynamics. Mr. E. C. Rhodes has been appointed to the University readership in statistics tenable at the London School of Economics. From 1919 to 1922 Mr. Rhodes was assistant in the Department of Applied Statistics at University College, London, and since 1922 has been lecturer in charge of the Department of Mathematics at University College, Leicester. The following Doctorates have been conferred: D.Sc. in Zoology, Rev. S. G. Brade-Birks (SouthEastern Agricultural College), for a thesis entitled "Notes on Myriapoda; the Economic Status of Diplopoda and Chilopoda and their Allies." D.Sc. in Chemistry, Mr. Sri Krishna (King's College), for a thesis entitled "Synthesis of Derivatives of Thianthren and Phenothioxin." Early Science at the Royal Society. February 1, 1676. Read a letter from Mr. Leewer hoeck relative to observations with his microscope. February 3, 1663. Mr. Hooke's account both the weight of the air in a large receiver 119 Englis wine pints, and of the proportion of the weight of th air to the weight of the water, was read. It wa ordered that whoever make report of an experimer but once made, should repeat it, for the sake of mor accuracy and certainty. 1669. Mr. Hooke produced a contrivance of his try whether a mechanical muscle could be made b art, performing without labour the same office whic a natural muscle doth in animals. 1675. The reading of Mr. Newton's observation on colours was continued. 1685. Dr. Papin for the entertainment of t Florentine envoy showed again the experiment water boiling in vacuo. February 4, 1662. Dr. Charleton moved, th the eyes of some animals might be frozen, in order see their structure the better. The operator w ordered to freeze some cats' eyes against the ne meeting, if the frost should hold. 1668. Two experiments with balls were made verify Dr. Wren's laws of motion. 1674. Mr. Hooke declared that he had made son discovery of the structure of a muscle by inspectio with a microscope. February 5, 1661. Dr. Wren was desired to thir of an easy way for an universal measure, different fro that of a pendulum. 1673. An experiment was made with Mr. Lister styptic liquor upon a dog, by opening one of his cru arteries lengthwise without cutting it asunder. 1679. The method of making experiments w further discoursed of; that they should be made in ord to prove a theory propounded: but Sir William Pet was of opinion, that they would be more faithfully ma and delivered if they were not made to help out a theo because that might prepossess and bias the expe menter. February 6, 1660. A committee was appoint for considering of proper questions to be inquired in the remotest parts of the world. 1666. A letter was read from the Duke of Brun wick to Mr. Oldenburg containing both his desire to made acquainted with the experiments made, and 1 offer of communicating in return what should come his knowledge in Germany and out of Italy. 1667. Mr. Oldenburg read a letter sent by Jo Denis, M.D., professor of philosophy and mathemat at Paris, relating to a late cure of an invetera phrensy by the transfusion of blood. 1678. Mr. Henshaw mentioned M. du Pont's pape which were in the hands of Mr. Evelyn, about the w of setting in new teeth artificially. dews. February 7, 1677. A discussion concerning m February 8, 1664. Mr. Bagnall produced a ba full of lapis amiantus or asbestos. He was desired procure more of it, in order to the making of paper 1687. Ordered that money be laid out for erecti a pole in the quadrangle of Gresham College management of a telescope. February 9, 1670. Mr. Hooke being asked wheth the air - vessel for a man to sit in was yet read answered that it was, and that he intended to m some experiments in it. 1686. Ordered that a committee who will voluntar meet once a week in Dr. Pope's lodgings be allow a fire and candle at the Society's charge. Societies and Academies. LONDON. Royal Society, January 31.-A. Mallock: Summary the results obtained from experiments made during e years 1918-1923 of the effects of temperature n the properties of metals. The results relate to the roperties of iron and steel in the neighbourhood of he critical temperature. The principal change which cours at that temperature is an abrupt alteration in pecific heat, which, as the metal passes to the highmperature state, is reduced to about one-third of is previous value. The coefficients of rigidity and hermal expansion undergo no discontinuous change. The rigidity decreases slowly as the temperature rises a low red heat, but at higher temperatures the hange is rapid. At a bright red heat the metal still tains elastic properties, but with greatly increased scosity, and thus oscillations which depend on igidity are quickly damped out. The presence of mall quantities of silicon, sulphur, phosphorus, and anganese in the samples used prevents any absolute onclusion being formed as to the effect produced by arbon alone, but it is clear that carbon lowers the ritical temperature, and prolongs the time occupied n changing from the high to the low temperature tate while the metal is cooling.-A. K. Goard and E. K. Rideal: Catalytic and induced reactions. t. I. An electrode of special type has been devised whereby it is possible to effect the comparison of the otentials of certain substances which behave irre-ersibly towards the platinum electrode. The action t cerous salts in effecting the induced oxidation of potassium arsenite, and the catalytic oxidation of ve reducing sugars, have been investigated from the point of view of oxidation potential. In the former ase the potentials observe the order: Cerous salt Inductor)-arsenite (acceptor)-equilibrium mixture - perceric salt; in the latter, the order: Reducing ugar-cerous salt-perceric salt. Pt. II.: Schönein's reaction (the separation of iodine from potasium iodide solution in the presence of hydrogen roxide and ferrous salts) conforms to the schemes or coupled and catalytic reactions described in Part I. of this paper. Direct evidence has been btained of the formation of a peroxide of iron by the action of hydrogen peroxide upon ferrous sulphate n neutral solution; it decomposes according to a nono-molecular law. This peroxide has been shown, by the method of electrometric titration under special conditions, to possess the essential formula Fe2O. -H. B. Dixon and G. Greenwood: On the velocity of sound in gases and vapours, and the ratio of the -pecific heats. The velocity of sound in certain apours and condensable gases was determined by ming the passage of a sound-wave between the two ends of a coiled lead pipe filled with the vapour or gas between 20° C. and 100° C., and comparing he rates with the velocity of sound through air in he same pipe. From the velocities found in the ipe the velocities in the free" gas are calculated, and from these results the specific heats of the gases and vapours are computed.-J. R. Partington and A. B. Howe: The ratio of the specific heats of nitrogen and of oxygen. The adiabatic expansion method of determining accurately the ratio of the pecific heats of a gas has been applied to nitrogen and oxygen. The gas was contained under pressure na spherical copper globe of about 60 litres apacity, immersed in a water-bath maintained at Constant temperature by means of an electrical hermostat, and is put into communication with free ir so that equalisation of pressures takes place Y Nitrogen at 20° C. 0-1759 0.2470 4.929 6.922 1.4045+0.0003 Oxygen at 20° C 01581 0-2204 5.056 7051 1.3946+0.0002 S. Barratt: The absorption spectra of mixed metallic vapours. In an absorption band spectrum, which is developed only in mixtures of the vapours of sodium and potassium, contrary to previous statements, the line IS-2p of magnesium has been observed in absorption.-E. P. Metcalfe and B. Venkatesachar : On selective absorption by luminous mercury vapour. The absorption of the components of the 5461 Å group (IIS) by luminous mercury vapour has been examined, with the aid of a Lummer-Gehrcke plate and an absorbing column 100 cm. long. All the satellites are strongly absorbed, under suitable conditions, with the exception of - ·237 Å, which is also absorbed, but to a much less degree. The ratio of emission to absorption is fairly constant for all the lines, except -237 A. All the resolved satellites, except 237 Å, have been reversed on a continuous bright background. The absorption and reversal of the lines 5769 Å (IP – 2d') and 5791 Å (1P −2D), for which the absorption centres are the same, and in the state IP, have been observed. Two satellites of 5769 Å (044 Å and -·050 Å) have been reversed. The effectiveness of long columns as radiators of weak lines is brought out by the observation of the feeble satellite -112 Å of 5679 Å in the light radiated from the end of a 100 cm. column carrying a current of 0.06 ampere per sq. cm. Association of Economic Biologists, December 7.R. S. Troup: Our tropical forests and their economic significance. The area of tropical forest within the British Empire is probably not less than 750,000 square miles, much of which is at present inaccessible or commercially unprofitable. Forests should be regarded as so much capital producing a steady interest or increment, and exploitation should extend to the utilisation of this increment while the capital is maintained and improved in quality. A definite forest policy having been laid down, the following steps are indicated: (1) reservation of areas to be retained permanently as forest, (2) settlement of rights, (3) demarcation, (4) detailed survey, and (5) preparation of working plans for the regulation of fellings and the conduct of regeneration and other works. So far as the utilisation of timber and other forest products is concerned, much research work remains to be carried out, for which purpose a Forest Products Research Board under the Department of Scientific and Industrial Research has recently been set up. Steps are also being taken to provide for the more efficient training not only of forest officers but also of research officers in specialised branches of forestry.-M. Grabham : Pseudococcus sacchari was and its associates in Madeira. Sugar cane introduced into Madeira early in the fifteenth century, but was wiped out in 1877 by a fungus, probably Aspergillus fulvus. Pseudococcus sacchari is known to have been present before the arrival of the Aspergillus, and the attack of the fungus was probably facilitated by the puncture of the coccid. After 1877 no sugar was grown for quite three years; then the Bourbon cane hitherto planted was replaced by the Yuba cane from Natal. The Pseudococcus either survived or was reintroduced, and has latterly enormously increased owing to the fostering care of the introduced Argentine ant. Though no control measures are undertaken, the Yuba cane flourishes and shows no deterioration in the crystallisable sugar yield. The Pseudococcus appears to have few parasites, and Coccinellid predators are thoroughly removed by the Argentine ant. A widely diffused red staining of the sheath accompanies the Pseudococcus attack. Its nature has not yet been satisfactorily determined. January 18.-E. B. Poulton: The relations of pure and applied biology (Presidential address). and Mineralogical Society, January 15.-Dr. A. E. H. Tutton in the chair.-A. F. Hallimond: The chemical classification of the mica group. Muscovite and phengite can be represented as mixtures of the molecules K2O. 3Al2O, . 6SiO, . aq. and K2O. (Fe,Mg)O . 2Al2O3, 6SiO. aq., the amount of water being somewhat variable. The best-known lithia micas are represented as follows: Lepidolite, K2O . Li2O . 2Ál2O ̧ . 6SiO,. aq.; cryophyllite, K,O. Li2O . (Fe, Mg)O. Al2O6SiO2. aq.; polylithionite, K2O. 2Li2O. R2O3. 6SiO2. aq. In the same way the dark micas can be represented as mixtures of phlogopite, K,O. 6(Mg,Fe)O. Al2O ̧ . 6SiO2 . aq., and two biotite types, namely, K2O. 4(Fe, Mg)O. 2Al2O3. 6SiO,. aq. K2O.6(Fe,Mg)O. 2Al2O3.6SiO2. aq. In the most acid biotites (from granite) the Al2O, is somewhat greater, with a corresponding replacement of (Fe, Mg)O. Al2O3 is, of course, often replaced by Fe2O3, (OH)2 by F2, etc. Graphical formulæ of oxidic compounds (salts) can be simplified by writing the connecting group -O- as a single symbol. The above empirical formulæ can be represented as salts of the single-chain hexa-silicic acid with K,Mg,Fe, etc., and with a diacid alumina group Al(OH),O, in which hydroxyl is replaceable by fluorine. The greater acidity of the white micas is accounted for by the presence of three acid groups -Si: O: Si- in the chain; biotite results from the addition of 3 (Fe, Mg)O to these groups, to form a normal salt; the most basic dark micas contain Al(OH),O,R in place of the simple group Al(OH),O, the aluminium becoming "amphoteric when the solution is very rich in (Fe,Mg)O.—A. Brammall and H. F. Harwood: Gold and silver as accessory minerals in the Dartmoor granite. Visible gold occurs as scanty minute specks in a porphyritic oligoclase-quartz-orthoclase rock containing a pale green fibrous amphibole and abundant sphene, together with apatite, zircon, monazite, and, occasionally, tourmaline. The silver has not been observed in hand specimens; assays show that it is usually in excess of the gold. The rock occurs as large loose boulders on Bittleford Down and at a few other localities.-Arthur Russell: Topaz from Cornwall, with an account of the localities, old and new, at which it is found. All the hitherto recorded occurrences of topaz in Cornwall are described, and new ones at Castle-an-Dinas Wolfram Mine, St. Columb Major; Belowda Beacon Mine, Roche; Beam Mine, St. Austell; and Mulberry Mine, Lanivet. At several localities, topaz is present in considerable quantities in the cassiterite-wolfram lodes; at Belowda it is especially abundant with tourmaline. Royal Meteorological Society, January 16.-Dr. C. Chree, president, in the chair.-C. Chree: Reflections on various subjects, including meteorology and sun-spots. Modern correlation methods applied to the question of the relationship between sun-spot frequency and meteorological, electrical, and magnetic phenomena show the importance of employing a long period of years. The results obtained from single 11-year periods are widely divergent in the case o meteorological data. A difficulty in arriving a conclusions being the length of the sun-spot cycle it is important to study any plan of arriving a results from shorter periods. So far as magneti phenomena are concerned, the difference betwee years of many and few sun-spots is of the sam nature as the difference between magnetically dis turbed and quiet days. The incidence of quiet an disturbed magnetic conditions is the same all ove the earth, but the difference between the two sets o conditions appears to be particularly prominent i high latitudes. There were now issued from de Bi international lists of quiet and disturbed days, 50 each class per month. The meteorological data fro these two sets of (Greenwich) days from stations r presentative of different parts of the earth might b contrasted. The new observatory in Shetland, from its high latitude, should be a promising station f the purpose. Royal Microscopical Society, January 16.-Prof. E J. Cheshire (Presidential address): The design of th petrological microscope. The design of this instru ment has been prejudicially affected by the fact tha the original petrological microscope was made by t simple addition of polarising adjuncts to the ordinar microscope. Its design should be considered de no As regards the necessary polarising elements, the da will soon arrive in which, to economise spa greater use will have to be made of the reflectin polariser, which is better adapted for low-power wor than the ordinary nicol prism. Further, there a serious objections to mounting the analyser immed ately above the objective; a new eye-piece should designed which would permit of the mounting of th analyser between the last lens vertex and Ramsde circle without so much sacrifice of angular field as necessary with the Huygenian eye-piece. The petr logical microscope suffers from the fact that sever of the five primary focal planes are inaccessibl This point should be specially considered in th design of the petrological microscope; as many foc planes as possible should be made accessible for ti introduction and withdrawal of the auxiliary polari ing elements. CAMBRIDGE. Philosophical Society, January 21.-Sir Erne Rutherford in the chair.-Sir Joseph Larmor: early formulation by Stokes of the theories of t rotatory polarisations of light.-H. F. Baker Theorems for a cubic curve in space.-E. H. Hankin On the angle of incidence in soaring flight.-H. V Turnbull Canonical forms of the quaternary cub associated with arbitrary quadrics.-C. G. F. James Complexes of conics and the Weddle surfaceS. Brodetsky and G. Smeal: On Graeffe's method f complex roots of algebraic equations.-J. Brill: the problem of four bodies. DUBLIN. Royal Irish Academy, January 14.-Prof. Sydne Young, president, in the chair.-J. K. Charleswort The glacial geology of the north-west of Irelan The region investigated covers some 4300 square mil It was invaded by an ice-sheet from Scotland moving general in a westerly direction and the western limits which coincided roughly with the line of Lough Swil and curved round the eastern end of the Sperrin Mi on to the shoulders of Slieve Beagh in Co. Monagha Later glaciers, centred in the Donegal hills, flow outwards to the Atlantic on the south-west, west, ar north, while on the east they swept over the Sperr Mts. and Slieve Gallion down the Valley of the Bann, over the site of Lough Neagh in the direction of Belfast, and on the south-east towards the Central Plain. The sequence in time of the two ice sheets is proved by superposition of boulder clays in Co. Derry. A re-advance of Scottish ice along the north Irish cast to the mouth of Lough Foyle succeeded a partial recession of the Donegal ice. The successive stages n the retreat of the Irish glaciers are marked by abundant moraines and by marginal drainage phenomena. PARIS. were Academy of Sciences, January 14.-M. Guillaume Bigourdan in the chair.-Ed. and G. Urbain: The multaneous presence of celtium and yttrium earths in some zirconium minerals. Zircons from four places of origin, malacon from two, and a specimen of brazilian badeleite were examined from the special point of view of the presence of yttrium earths and t celtium. All these zirconium minerals roved to contain rare earths and celtium, the prortion of celtium increasing with the proportion of ttrium earths.-P. A. Dangeard: Sexual reproducon in Marchantia polymorpha in its relations with eilular structure. At the moment of impregnation ne oosphere of Marchantia contains, besides the eniale nucleus, three structures to which the name These or vacuome, plastidome, and cytome are given. hree structures are transmitted to each generation without discontinuity.-Paul Marchal: Contribution the study of the evolutive cycle of Eriosoma arigerum.—André Blondel and Jean Rey: A new erification of the law of perception of light flashes at the limiting range: the case of very short durations. -A. Rateau: Hovering flight against the wind. A mathematical proof of a formula giving the principal ws of the Katzmayr effect.-M. Félix Lagrange was elected correspondant of the Academy for the ction of medicine and surgery, in succession to M Bordet, elected foreign associate.-Ph. Le CorDeiller: The substitutions of the complex modular group which preserves a quadratic form with complex efficients.-Paul Mentré: Complexes with quaduple inflectional focus.-E. Cartan: Similar conxion of surfaces.-Ervand Kogbetliantz : The absolute summation of series by arithmetical means. -A. Vakselj: The linear differential equation of the econd order with four singular points.-D. Menchoff : The convergence of series of orthogonal functions.A. Kolmogoroff and G. Seliverstoff: The convergence of Fourier's series. Constant Lurquin: A fundanental proposition of probability. A discussion of he Bienaymé-Tchebycheff criterion.-R. Risser : Naves of emersion in a canal of given width. Noaillon: Reply to the observations of M. Pascal n superficial circulation.-André Metz: The interpretation of Michelson's experiment. A criticism and orrection of a recent communication by M. Brylinski n tais subject.-J. Le Roux: The co-ordination of ovements and the notion of time.-H. Chipart: The propagation of light in media possessing periodic tructure.-N. Perrakis and A. Massol: A method of etermination of micro-miscibilities. An account of method for the study of the miscibility of alcohol, ater, and petrol, in which the temperature is kept onstant and one of the constituents added until the rbidity point is reacned.-Mlle. Germaine Cauquil : The esterification of cyclohexanol and of some of its omologues. In equimolecular proportions at 95° C., he systems cyclohexanol-acetic acid, o-methylcycloexanol-acetic acid, and dimethyl-1.3.4-cycloexanol-acetic acid give equilibria at 55.6 per cent., 9-8 per cent., and 47.5 per cent. respectively. The esterification velocity constants were measured for the three alcohols.-A. Damiens: The power of spontaneous transformation of yellow mercuric iodide.-Mlle. Suzanne Veil: The evolution of the cupric hydroxide molecule in the presence of water. Measurements of the changes in the coefficient of magnetisation corresponding with the colour changes of cupric hydroxide in water.-V. Auger: Two attempts to replace the theory of ions by a theory based on the molecular theory of water. A critical discussion of the views put forward by Armstrong (Comptes rendus, June 25, 1923, p. 1892) and by Kling and Lassieur (Comptes rendus, July 9, 1923, p. 109).-Maurice Piettre: The proteids of lactoserum. Their separation by the acetone method.J. Thoulet: The circulation of the ocean.-L. M. Bétancès: The primitive cell of the blood.-L. Bounoure: The endodermic dorsal derivatives and first genital outline in the tailless batrachians.Jacques Benoit: The signification of the right rudimentary genital gland in the hen. This gland, hitherto regarded as the right rudimentary ovary, should be considered as having the value of a rudimentary testicle.-Y. Manouelian and J. Viala: Encephalitozoon rabiei, the parasite of hydrophobia.L. Panisset and J. Verge Immunity in bird diphtheria and contagious epithelioma in poultry. CHRISTIANIA. Scientific Society, October 26.-Prof. Halvdan Koht, president, in the chair.-H. H. Gran: The melting of the snow as the chief of the main causes of the increasing production of organic substance in the sea near the coasts of Northern Europe in the springtime. The determination of the production of organic substance was made by quantitative determination of the plankton, by determination of the changing concentration of oxygen in the water, and by determination of the fertilising power of the water. November 17.-Prof. H. Goldschmidt in the chair. -Johs. Lindeman Colloids and the stability of colloid solutions. The stability of a colloid system (the hydrosol of ferric hydroxide) is greater if it is formed in the presence of nuclei. WASHINGTON, D.C. National Academy of Sciences (Proc. Vol. 9, No. II, November).—A. H. Compton: The quantum integral and diffraction by a crystal. From considerations of energy and momentum principles and the quantum postulate, expressions for diffraction by a crystal grating are obtained. Bragg's expression for the diffraction of X-rays by a crystal is derived from the equations.-W. Hovgaard: The principle of minimum energy and the motion of fluids. In the case of an incompressible fluid filling completely a region between two boundaries subject to prescribed motions, the motion of the fluid is irrotational under the condition of minimum energy. It is shown further that, given that the motion of the liquid is irrotational, the motion is of necessity always one of minimum energy.-P. W. Bridgman: The volume changes of five gases under high pressures. The gases used were hydrogen, helium, ammonia, nitrogen, and argon; the maximum pressure was 15,000 kg./cm.2 and the temperature about 60°. Gas under a pressure of 2000 kg./cm.2 is introduced into a cylinder filled with kerosene and additional pressure is applied by a piston. The volume decrease is greatest for the monatomic gases though at very high pressures, nitrogen retains great compressibility owing to its complex structure. The densities under 15,000 kg./cm. pressure are calculated hydrogen 0.1301, |