AGRICULTURAL NOTES.

THE annual report of the Transvaal Department of Agriculture for 1903-4 is a volume of more than 400 pages, which contains, in addition to an introduction by the director, reports on the fourteen sections into which the work of the department falls. In discussing the personnel of the department, the director refers to the difficulty of obtaining expert assistants, a difficulty which, so far as agriculture is concerned, exists in all countries supplied from Britain, and even in such countries as the United States, where the training of the expert receives more attention than it does here. Many of the chief positions in the Transvaal department have now been filled up, but assistants are still required, and as the work expands it is probable that a considerable number will be engaged. The report states that men for scientific work will doubtless best be obtained from amongst students who have had good careers at one or other of the universities, and who have done a certain amount of research after taking their degree. A thorough grounding in pure science is a sine qua non, and if they are not acquainted with the applied side of Science, this knowledge will have to be acquired in our laboratories whilst acting as assistants to the Chief of their particular Division.

The above named report contains many interesting paragraphs. Here is one that appears under the heading "Farmers' Cooperative Experiment Reports":-From General Louis Botha, Pretoria, "They (mangels from England sent for trial by the Department) do not grow so quickly as other sorts of root-crops, but if sown early they will grow splendidly and give a good winter crop in May; therefore I ordered a big quantity which I intend to use this year.

In papers contributed to the first four parts of the Agricultural Journal of the Cape of Good Hope for the current year, Mr. D. E. Hutchins, conservator of forests at Cape Town, makes out a strong case for the extension of tree planting in South Africa. The coast districts have a very favourable climate, growth is rapid, and the quality of the timber produced is good; but while native resources have not been developed, timber to the value of 1 millions is imported annually. There is no reason why most of the wood required for building and mining purposes should not be grown in the country, and it is estimated that every 1. spent in afforesting suitable land would bring in an annual revenue of 11. in thirty-five years' time! If Mr. Hutchins can convince the financier that this estimate is correct, South Africa should soon grow its own timber; but in this branch of agriculture the sower seldom reaps, and the investor is not easily convinced. It is likely, therefore, that in South Africa, as elsewhere, the lack of capital will prove a more serious difficulty to the enthusiastic forester than either soil or climate.

The

In a recent number of the Bulletin of the College of Agriculture, Tokyo Imperial University, there is an article of considerable interest to British agriculturists. Japanese farmer, like the English farmer of half a century ago, is given to employing lime more freely than is good for his land, and in some districts the injury done by liming has caused the authorities to interfere with the practice. Following up some work by Kellner and Böttcher on the effects of lime on the action of certain phosphates, Nagaoka investigated the results of employing a number of phosphatic fertilisers on limed and on unlimed land. Rice was grown, and it was shown that lime greatly interfered with the action of those phosphatic manures which were of animal origin, such as bone meal or fish bones; on the other hand, when the phosphates were derived from a vegetable source, the effects of lime were not very pronounced. The injury was about twice as great in manures of animal as in those of vegetable origin. The injurious action of lime extended into second year. Nagaoka's results confirm those obtained by Kellner and Böttcher in Germany, and indicate that such marures as bone meal and fish meal should not be used on recently limed soils.

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We have received from the committee of the Lawes Agricultural Trust a copy of the report of the director, Mr. A. D. Hall, on the werk dene at the Rothamsted Experi

mental Station for the year ending March 31. The well known experimental fields are still continued without any essential change; in addition, a new field has been laid out to test the residual value of various manures in the second and succeeding years after their application. Other experiments deal with calcium cyanamide, the new manure containing nitrogen derived from the atmosphere, and with the various cultivations of bacteria which have been recently introduced for the inoculation of leguminous crops, with the view of making them more efficient collectors of atmospheric nitrogen. During the year in question seven papers have been issued from the station, all of which deal with investigations on the soil, methods of soil analysis, &c. The annual losses of carbonate of lime in the Rothamsted soil have been determined, both that due to natural agencies and that caused by the use of manures. Certain restorative actions have been investigated which account for the maintenance of the fertility of many soils which are almost devoid of lime. Another of the papers deals with the remarkable accumulations of fertility in certain plots of land which have been allowed to run wild for the last twenty years, and have in that time gained nitrogen to an extent not readily explicable by the accepted theories. The Lawes Trust committee continues to find its income very inadequate to the proper development of the station; only donations and subscriptions from various sources, including 300l. from the Goldsmiths' Company, gol. from the Clothworkers' Company, 5ol. from Lord Rothschild, &c., have prevented a serious deficit on the year's working. Mr. J. F. Mason has also promised to erect and equip a new laboratory for agricultural bacteriology, which will be the first of its kind in this country, as a continuance of the experiments carried on for many years by his father, the late Mr. James Mason, at Eynsham Hall, Oxon.

REPORTS ON SEA FISHERIES.

THE report for 1904 on the Lancashire Sea Fisheries Laboratory at the University of Liverpool and the sea fish hatchery at Piel contains an introduction and general account of the year's work, written, as usual, by Prof. Herdman, the honorary director of the scientific work.

A report upon the sea fish hatchery at Piel, by Mr. Andrew Scott, shows that more than a million plaice fry and more than twelve million flounder fry were liberated, the result of hatching eggs laid by fish caught in the autumn and confined in tanks at the hatchery. The useful results to the fisheries of thus confining spawners and turning out the newly hatched fry have yet to be demonstrated.

A paper upon the tow-nettings collected in the Irish Sea, contributed by Mr. Scott, is of little value, because it is far too general, the contents of the tow-nets not having been identified. Such records as Copepoda, medusoids, gelatinous algæ, a fish egg," are perhaps of some value, but of very little. It appears to us that had less been attempted, and some one group properly worked, the value of the paper would have been much greater. In referring to the occurrence of pelagic fish eggs, the scientific names of the various species might have been mentioned with advantage.

Bacteriological investigations in relation to shell-fish pollution by sewage matter, by Mr. James Johnstone, is an interesting paper continuing an investigation carried on during the previous year. Mr. Johnstone is also responsible for a paper upon plaice-marking experiments, and for another upon the internal parasites and diseased conditions of fishes. The plaice-marking experiments are upon a small scale, but no doubt will give results of interest in time. Dr. J. Travis Jenkins, recently appointed to the post of superintendent of fisheries of the district, contributes an interesting discussion of official fishery statistics, from which it appears that the Board of Trade returns are not always accurate. Dr. Jenkins's remarks

1 Report or 1904 on the Lancashire Sea Fisheries Laboratory at University of Liverpool and the Sea-fish Hatchery at Piel; and Syllabu Lessons on Marine Biology. (Liverpool, 1905.

upon the cockle industry are both interesting and important.

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The volume contains several plates and woodcuts, and is in paper covers. The education committee of Lancashire County Council provided funds for the instruction of fishermen at the Piel hatchery, and forty-five fishermen attended the class which was held in the spring by Mr. James Johnstone. A "Syllabus of the Lessons in Marine Biology given in the Practical Classes for Fishermen" has been revised, and is now published as a separate volume. It is difficult to estimate the value to the fishermen of the benefit to be derived from a superficial knowledge of marine biology, but the value to the laboratury no doubt lies in the fact that the men send in specimens of animals and plants taken in the course of their fishing operations.

The Danish fishery and hydrographical contributions to the international North Sea fisheries investigations,' lately issued, include two papers dealing with fishery matters, one by Mr. Johs. Schmidt being concerned with the pelagic post-larval stages of the two species of halibut Hippoglossus vulgaris, Flem., and H. hippoglossoides (Walb.). Mr. Schmidt points out that the best distinction between these two species is not in the number of fin-rays, but in the number of vertebræ, and he found certain post-larval fishes off Iceland and the Faroe Islands which agreed in the number of vertebrae with the adults of H. vulgaris. The material from which he determined the young stages of H. hippoglossoides was taken by the Danish Ingolf Expedition.

The other fishery paper is by Dr. A. C. Johansen, and is entitled Contributions to the Biology of the Plaice with Special Regard to the Danish Plaice Fishery," and is the first report published upon the subject. The paper is exceedingly interesting, the results, chiefly in regard to the growth and migrations of the plaice, having been obtained by recording the length of a number of fish, marking them with a label, and returning them to the sea to be caught later on by one of the numerous fishing boats. A fair percentage of the fish have been recovered, and by re-measuring these fish their rate of growth during the time between their marking and re-capture has been determined. An interesting part of this experiment was the transplanting of fish from one ground to another, by which it was found that on some grounds they would grow three or four times as rapidly as upon other grounds. Experiments upon the same lines have been carried out by the English staff with similar results, but the official English report is not yet published. The marking experiments have also shown that in Danish waters there are decided migrations of plaice at different times of the year, the tendency being for the fish to work into shallower water during the spring and into deeper water during the

autumn.

Dr. Martin Knudsen contributes a paper upon the hydrography of the North Atlantic Ocean, while Mr. J. N. Nielsen writes upon the hydrography of the waters of the Faroe Islands and Iceland during 1903. In both these papers we should have liked to see either an introduction stating the objects of the investigation or a summary of results, as, to those who are not hydrographers, the results obtained are not very clearly set forth. It is perhaps too early to attempt to connect the observed physical phenomena with the movements of the fish, but no doubt, as more material comes to hand, the biological results of the international investigations will be shown to be closely dependent upon the physical conditions observed by the hydrographical staff.

A paper by Mr. Neils Bjerrum, on the determination of oxygen in sea-water, is bound in with Mr. Nielsen's paper already referred to. Mr. Bjerrum has adopted a method of ** preserving" the water samples taken in mid-ocean until they can be accurately analysed on land, and it appears that his method of adding to the water samples a solution of manganous chloride and caustic soda containing iodide of potassium has been very satisfactory.

FRANK BALFOUR BROWNE.

1 Meddelelser fra Kommissionen for Havundersøgelser. (Copenhagen, 1904-5-)

UNIVERSITY AND EDUCATIONAL INTELLIGENCE.

OXFORD.-A statute was brought before Congregation on June 6 to provide a delegacy to superintend the in- ̧ struction of candidates for the Indian Forest Service, and to grant diplomas in forestry. The proposal to establish a diploma in forestry in the university has arisen from the recent decision of the Secretary of State for India to send the Indian forestry students, hitherto trained at the Cocpers Hill Engineering College, to receive their special training in forestry at Oxford. Those students under the regulations just issued by the India Office will be selected by a competitive examination held by the Civil Service examiners every summer. They must be natural born British subjects of not less than eighteen or more than twenty years of age on the January 1 before their selection. They will be required, before becoming candidates, to have passed Responsions or an equivalent examination. The subjects of be:the competitive examination will (1) mechanics and physics; (2) chemistry; (3) zoology ; (4) botany.

After selection the students will be probationer for about three years. For the first two years they will be required to study at Oxford, and their course will include theoretical and practical forestry, and subjects auxiliary to forestry, viz. organic chemistry and the chemistry of soils, geology, forest botany, forest entomology, mathematics, German, and book-keeping. During the third year of probation they will receive practical instruction, visiting Continental forests under suitable supervision. The first competitive examination will be held on August 20 for the selection of not less than nine candidates. Applications for admission must be made to the India Office by July 1.

The Junior Scientific Club gave a conversazione in the museum on Tuesday, May 30, at which more than a thousand visitors were present. Lectures and demonstrations were given by Prof. Poulton, Dr. Tutton, Dr. Brereton Baker, and Mr. E. P. Poulton, and there were a large number of scientific exhibits.

The Robert Boyle lecture for 1905 was given by Sir Victor Horsley on Monday, June 5, in New College Hall. The subject of the lecture was "The Cerebellum."

CAMBRIDGE.-A little pamphlet has just been published on the authority of the Vice-Chancellor containing the names of all those who voted on the report of the examinations and the way they voted. An analysis of the poll shows that amongst the resident members of the university 288 voted in favour of allowing a substitute for Greek in the previous examination and 240 against. Thus the residents had, out of a total of 528 votes, the substantial majority of 48; they were, however, swamped by the nonresident vote. Only four colleges, King's, Christ's, Trinity, and Downing, showed a majority amongst both residents and non-residents in favour of the proposed change.

Prof. Lewis gives notice that a course of lectures and demonstrations in crystallography will be given in the mineralogical lecture-room during the long vacation, beginning at 9 a.m. on Friday, July 7.

The observatory syndicate has reported upon the management of the sum of 5000l. bequeathed by the late Mr. Frank McClean for improving the instrumental equipment of the Newall Observatory. It recommends that the sum be invested, and that the disposal of both the interest and, if advisable, the capital, be in the hands of the syndicate, and that the accounts be annually audited and published with the university accounts.

The special board of medicine has drafted ordinances which, if they pass the Senate, will allow a candidate for the M.B. or M.D., if resident abroad, to take his degree in absentia.

THE annual conversazione of University College, London, will be held on the evening of Wednesday, June 28. There will be scientific and other exhibits illustrating the work of the various departments of the college.

MR. E. BROWN, lecturer on applied mechanics at the University of Liverpool, has been appointed assistant professor in civil engineering and applied mechanics in the McGill University at Montreal.

DR. J. E. DUERDEN, of the University of Michigan, formerly curator of the museum, Jamaica, has been appointed professor of zoology at the Rhodes University College, Grahamstown, Cape Colony.

A COURSE of eight lectures in advanced zoology on "The Prosobranchiate Mollusca " is being given in connection with the University of London in the lecture room of the Chelsea Physic Garden by Mr. J. E. S. Moore on Mondays and Thursdays during June. There is no fee for the course; cards of admission and a detailed syllabus may be had on application to the academic registrar, University of London, South Kensington, S.W.

THE King has approved the charter for the constitution of the University of Sheffield. On June 3 the ProChancellor formally handed over the charter to the ViceChancellor, Dr. Hicks, F.R.S., and congratulatory speeches were made. The King and Queen have consented to open the new university buildings in July. An endowment fund of about 140,000l. has been raised in Sheffield, and the City Council and the councils of neighbouring boroughs and counties have guaranteed annual rate aid equivalent to an even larger capital sum. The first Chancellor of the university is the Duke of Norfolk.

WE learn from Science that Prof. Asaph Hall, jun., has resigned the professorship of astronomy and directorship of the observatory at the University of Michigan. Prof. W. T. Hussey, of the Lick Observatory, has been elected his successor. Prof. S. J. Barnett, of Stanford University, has accepted the chair of physics at Tulane University, vacant by the resignation of Dr. Brown Ayres to accept the presidency of the University of Tennessee. At Williams College, Mr. W. E. McElfresh has been promoted to the Thomas T. Reed professorship of physics, and Mr. H. L. Clelland to a professorship in geology. M. Gabriel Bertrand has been appointed to succeed the late M. Duclaux as lecturer on biological chemistry at the Paris Faculty of Science.

IT is announced, Science states, that 360,000l. has been contributed toward the endowment of 500,000l. which is being collected to increase the present amount available for the salaries of the teaching staff of the college of Harvard University. The circular which appeals for additional subscriptions says:- The position of Harvard to-day among American universities is due not so much to its age, traditions, or able administration as to its noble line of teachers. That the teachers in the college should be the best in the land; that the older professors should be free from the cares of a straitened income; that the younger teachers should be able to give themselves without distraction to their work, and that the best men should not be drawn away to other colleges, but should see before them reasonable promotion in work and salary, is essential to the leadership of Harvard and the culture of her sons." It is pointed out that the total of salaries in Harvard College is about 87,600l., and the average per capita allowance for the staff of 279 teachers is only 3147.

AN article entitled Some Candid Impressions of England" is contributed to the current number of the National Review by a "German Resident." The first fact which strikes the contributor is the indifference of Englishmen to their individual duties as citizens of a great Empire, and it seems to him, looking at English schools, that the mainspring of German success is here. He says:-" Our youths, like your youths, are human, and would be lazy if there were no penalty for idleness. But the fact that those who are negligent and lazy at school have to put in an extra year of service, acts as a stimulus and compels the German boy to work, where the English boy spends his time in play." In another place :-"I look at England and see the want of such an influence even in your public schools, which are good in a way, so far as they form character, but bad in that they neglect intellect." As for our primary education, its product seems to the critic surprisingly bad. He says the knowledge imparted in our

elementary schools does not seem to be such as is required for the making of good citizens. The majority of our workers, he remarks, read little but the sporting Press, and care for little but betting and sport. It is pointed out that the Germans have destroyed in this generation the superstition that Germany makes only poor and cheap articles. "Our Mercedes motors and scientific and optical instruments are the best and most expensive in the world, and no English article of their class can for a moment compete with them.'

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THE annual report of the council of the City and Guilds of London Institute was adopted at the yearly meeting of the institute held on June 1. The council directs attention to the diminished income of the institute, owing to the fact that the Mercers' Company, the Fishmongers' Company, and the Corporation have made reductions in their contributions. No reason, it is said, has been assigned for these reductions. At the invitation of the Lord Chancellor, a meeting of the representatives of the principal companies has been held to discuss the situation, and a resolution has been passed expressing a hope that the livery companies will increase, rather than diminish, their subscriptions. The total income for the past year, including donations for special purposes, amounted 43,4321., of which the Corporation and the livery companies contributed 23,3081., the remainder coming from fees and other receipts. In the previous year the income was 46,8291., of which the Corporation and livery companies contributed 29,3851. Sir John Wolfe Barry, in his speech moving the adoption of the report, alluded to an interview with the chairman of the Departmental Committee on the Royal College of Science, South Kensington. He gathered that the general idea of the scheme which will be submitted to the council of the institute is a federation or coordination of all the teaching institutions which are gathered round about South Kensington, and when this takes place the institutions will be in intimate connection with the university. It is held that a system of this kind will be a very great benefit, not only to the general teaching given, but also to post-graduate teaching, which will be largely developed, it is hoped, in the future.

THE report of the Commissioner of Education for the year 1903 has now been published by the United States Bureau of Education. It contains in its 1327 pages an abundance of information concerning all grades of American education, and parts of the educational systems of other countries. It is only possible here to refer to a few of its contents. Dr. Charles F. Thwing, president of Western Reserve University, contributes a chapter on the development of American universities, their organisation, conduct, and relations to the life of the nation. The chapter shows that the growth of university endowment funds has kept pace in the United States with that of the wealth of the country at large. For example, the productive funds of Yale College have increased from about 6000l. in 1830 to more than 1,000,000l. at the present time. The growth of libraries also has been significant in particular instances, yet Dr. Thwing says the "libraries of most colleges are inadequately furnished and inefficiently administered.' The functions of universities in American communities are considered under various aspects. First, as conserving forces in the presence of a democracy inclined to make all things new; then as inspiring with high moral ideals an age inclined to pursue mere material aims. As an agency to promote systematic research-the seeking after truth as such the university fulfils an increasingly useful function. It presents, as the chapter points out, materials for the study of all truth, in the world of nature and in the world of man. Another chapter of the report deals with education in France, and includes some interesting statistics concerning French universities. It appears that the registration in State universities has increased by about 60 per cent. since 1887, the total registration for 1901 being 20,931 students. The University of Paris greatly outnumbers all others in this respect, its total registration being 12,289 students. Lyons, with 2458 students, and Bordeaux, with 2119, stand next to Paris. As the distribution by faculties, law leads with 10,152 students, medicine follows with 8627, science comes third with 3910 students, and is closely followed by the faculties of letters with 3723 students.

SOCIETIES AND ACADEMIES.

LONDON.

Royal Society, March 30.-"The Theory of Photographic Processes, Part ii. On the Chemical Dynamics of Development, including the Microscopy of the Image." By S. E. Sheppard and C. E. K. Mees. Communicated by Sir William Ramsay, K.C.B., F.R.S.

This paper forms a continuation of a preceding one on the kinetics of development (Proc., Ixxiv. pp. 447-473). By microscopical methods, the growth in the thickness of the reduced layer of silver particles, in their size and their number, under varying conditions of exposure and development, has been studied. For the structure of the developed negative the following facts were ascertained :

(a) With constant development for a short time the depth of the image is independent of the exposure.

(b) With increased time the depth increases very rapidly at first, reaching a maximum for each exposure, after which it is constant, while the density of reduced silver still increases.

(c) With long development the depth increases somewhat with the exposure, a limit naturally being fixed by that of the film.

Size of the Grain.-This increases with the time of development, the rate being a function of the exposure, but the limiting size independent of this, and fixed by the original haloid grain. Thus in the early stages of development the size of the grain increases with exposure, but on ultimate development is independent of it.

Soluble bromides at moderate concentration give a smaller grain for the same time of development, but depending on the exposure. On ultimate development the

size becomes the same.

Number of Grains Reduced.-In the surface-area the number is independent of the exposure, but in the volume unit for moderately long development the number increases with the exposure, and is nearly proportional to the density. It increases rapidly with the time of development, more so than the density, and soon reaches a maximum.

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When plates are exposed through the glass side, the thickness of the reduced layer is much the same, but the numbers less. Further, the grains nearer the glass are larger, showing that the more exposed grains start development first. Generally, each grain develops as an isolated system, only uniting to form aggregates when the packing is close, as in high exposures. The true reactionlaver is in the gelatin skin surrounding the grain, its thickness being of the order 0-0005 mm., and the reaction is similar to the catalysis of H2O, by colloidal metals, with convection excluded.

Early Stages of Development.-From considerations of the order of reactions the validity of the Watkins factorial method of development is discussed, and the "time of appearance" shown to be a measure of the developmentvelocity for the initial stage of development. For ferrous oxalate this initial velocity is shown to be proportional to the concentration.

Effect of temperature for ferrous oxalate can be represented by the formula of van 't Hoff, log K=-A/T+C, but the temperature-coefficient for 10°, K+10°/K, varies for different developers and emulsions, and cannot serve as a criterion for distinguishing rate of chemical action from diffusion in development.

It is further shown that "tanning" the film with formalin does not alter the development-velocity.

For the "penetration" of the developer, it was found that with plates exposed from the back the image appeared on the glass or film side first according to the exposure. This is explained by consideration of the micro-structure of the exposed film, and the conclusion is again obtained that the re-activity or readiness to start development of the individual grain is a steady function of the exposure.

From the absolute "time of appearance" of the image at the bark it is concluded that the diffusion-induction is not great, especially since other considerations show that in the early stages of development the chemical reaction has more influence than diffusion.

Chemical Society, May 17.-Prof. R. Meldola, F. R.S., president, in the chair.-The desmotropic form of substances of the ethyl acetoacetate type in the homogeneous state and dissolved in neutral media: J. W. Brühl and H. Schröder. The authors claim to have established by optical measurements with solutions in various media that both the ethyl acetoacetates and their secondary and tertiary alkyl derivatives, and also the camphorcarboxylic esters and their alkyl derivatives, display a pure uniform ketonic structure, and are free from the enolic forms.The chlorination of methyl derivatives of pyridine, part i., 2-methylpyridine: W. J. Sell. The compound CHCI,N was obtained by chlorinating 2-methylpyridine in hydrochloric acid solution.-The absorption spectra of uric acid, murexide, and the ureides, in relation to colour and their chemical structure: W. N. Hartley. The ureides, diureides, and some oxypurin derivatives are divided by the characters of their absorption spectra into two groups, the oximino-ketones with no ethylenic linking associated with the carbonyl groups, and the substances which have one or more such linkings.-Observations on chemical structure and physical properties associated with the theory of colour: W. N. Hartley. The main feature in a coloured substance is the occurrence in two parts of the molecule of ethylenic and benzenoid groupings and of ketonic groupings. The explanation of colour, based on the change from a double linking (ketonic) to a single linking (enolic), should, if sound, be capable of explaining the occurrence of six bands in the spectrum of benzene, four in that of naphthalene, and four in that of anthracene. It is shown how this is possible from Kekulé's formula for benzene, and how this formula may be reconciled with the "centric formula. Further studies on dihydroxymaleic acid: H. J. H. Fenton. This paper describes the results of a study of the condensation of the acid with ammonia, and the behaviour of the acid and its esters towards various hydrazines.-The influence of light on diazo-reactions, preliminary notice: K. J. P. Orton and J. E. Coates, and (in part) F. Burdett.-Behaviour of solutions of propyl alcohol towards semi-permeable membranes A. Findlay and F. C. Short. Some years ago Pickering stated that when a porous pot containing a 57 per cent. aqueous solution of propyl alcohol was immersed in either pure water or pure propyl alcohol, the water or the alcohol passed inwards to the solution. authors have been unable to confirm Pickering's experiments, and suggest that the behaviour observed by him might be temporary and due to differences in the velocity of the diffusion of the pure liquids and the solution.-The thermal decomposition of formaldehyde and acetaldehyde : W. A. Bone and H. L. Smith. Formaldehyde decomposes at all temperatures between 400° and 1125° in accordance with the equation CH,O=CO+H2, and acetaldehyde at 400° in accordance with the equation CH,.CHO=CH,+Co. -The synthesis of formaldehyde: D. L. Chapman and A. Holt, jun. The authors have succeeded in synthesising formaldehyde by maintaining a platinum wire at a high temperature in the following mixtures: (a) carbon monoxide and hydrogen; (b) carbon monoxide, hydrogen, and steam; (c) carbon monoxide and steam; (d) carbon dioxide and hydrogen.-Oxymercuric perchlorates and the action of alcohol on mercury perchlorates: M. Chikashigé. Three new oxymercuric perchlorates are described.--The constitution of pilocarpine, part v., conversion of isopilocarpine into pilocarpine: H. A. D. Jowett.

The

Royal Meteorological Society, May 17.- Capt D. Wilson-Barker, vice-president, in the chair.-Measurement of evaporation: R. Strachan. The author pointed out that the rainfall, evaporation, and percolation are related to each other, and that rainfall is commonly considered to form the sum of evaporation and percolation. If two of these quantities are found by experiment or observation, the other is assumed to be known. This, however, does not always hold good. A month may be very dry, and still evaporation will go on at the expense of previous percolation-and otherwise. A month may be excessively wet, then there may be another item to take into account, viz. overflow. As, unfortunately, it is not possible to make evaporation and percolation the subject of experi

ment, except at a very few observatories, the author thinks it is desirable to be able to estimate, even empirically, the probable amounts of each. By using the meteorological data published for the Royal Observatory, Greenwich, he has calculated the probable evaporation for the year 1898, which agrees very closely with the observed evaporation Camden Square and also at Croydon. On logarithmic slide-rule for reducing readings of the barometer to sea-level: J. Ball. This has been devised for the purpose of saving the time and labour usually occupied in working out the corrections from the international meteorological tables.

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Royal Microscopical Society, May 17.-Dr. Dukinfield H. Scott, F.R.S., president, in the chair.-The movements of diatoms and other microscopic plants: D. D. Jackson. The author describes the observations and experiments made by him, some with artificial diatoms, which have led him to the conclusion that the movements referred to are caused by the escape of oxygen gas evolved in these organisms.

Faraday Society, May 18.-Dr F. Mollwo Perkin. treasurer, in the chair.-An application to electrolytes of the hydrate theory of solutions: Dr. T. Martin Lowry. The object of the paper is to consider the possibility of extending the hydrate theory to electrolytes in such a way as to take account of the observations which form the experimental basis of the theory of electrolytic dissociation. The hydrate theory postulates that an aqueous salt solution consists of a mixture of hydrates in equilibrium with the solvent and with one another. But it must be supposed that even in solution there is a limit to the possibility of hydrate formation, so that ultimately a stage will be reached at which the molecule as such will be unable to combine with any further quantity of water. The ionisation of an aqueous electrolyte consists essentially in a further process of hydration whereby the fully hydrated molecule combines with an additional quantity of water to form two or more hydrated ions. The hydration of the ions is thus conceived to be the primary cause of the ionisation of aqueous electrolytes. It is believed that this extension of the hydrate theory to the phenomena of electrolysis may help to remove the fundamental difficulty of Arrhenius's theory, namely, the absence of a motive for electrolytic dissociation.

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Physical Society, May 26.-Meeting at the National Physical Laboratory by invitation of the director, Dr. Glazebrook. The following special demonstrations made-The specific heat of iron at high temperatures: Dr. J. A. Harker. A knowledge of the specific heat of iron is important in the determination of high temperatures by calorimetric methods. Dr. Harker has determined the total heat of iron up to temperatures of 900° C. by heating the specimen in an electric furnace, the temperature of which was determined by a resistance thermometer, and dropping the iron into a water calorimeter. Dr. Harker also exhibited some new types of electric furnace for the attainment in absence of noxious gases of temperatures between 800° C. and 2200° C. The conductor conveying the electric current is a tube of solid electrolytes similar in composition to the filament of a Nernst lamp. An essential feature is that, for many purposes, the usefulness and life of a furnace constructed in this way may be much increased by adopting a "cascade" system of heating.-Apparatus for the measurement of small inductances: A. Campbell. The method of measurement is that adopted by Max Wien, and described by him in a paper on Magnetisation by Alternating Currents" (Wied. Ann., xiii., August, 1898). It is a modification of Maxwell's method of comparing two self-inductances, the source of voltage being alternating, and the indicating instrument a tuned optical telephone or vibration galvanometer.-Two new optical benches constructed for the laboratory by Messrs. R. and J. Beck J. Selby. One of these is specially designed for the rapid testing of spherical and cylindrical lenses, such as are found in oculists' trial cases. The second bench is designed for the determination of the loss of light by absorption and reflection in telescopes and binoculars.

CAMBRIDGE.

Philosophical Society, May 1.-Pro'. Liveing, vicepresident, in the chair. On the striation of the positive column in electric discharges: Prof. Thomson. The author considered the ionisation in a discharge tube by the collision of charged ions as well as of corpuscles against the molecules of a gas, and showed that if the pressure in the tube and the electric current through it had values situated between certain limits, there would be periodic alternations in the positive column analogous to striations.-On the calculation of the coefficient of re-combination of the ions and the size of the ions: Prof. Thomson. The re-combination of ions is due to oppositely charged ions attracting each other and forming a single system. When the ions are at a distance r apart the work required to separate them to an infinite distance is e2/r, hence two ions starting from a distance r apart will not describe closed orbits about each other, i.e. will not combine if their kinetic energy is greater than er. Since the ions behave like the molecules of a gas, their kinetic energy will depend only upon the temperature, and can be calculated when that is known. If T is this kinetic energy, then for combination to take place er must be greater than T, or r less than e2/T. Hence to find the number of re-combinations in any time, all we have to do is to find the number of pairs of ions which within that time get within a distance e2/T of each other. This number, and hence the coefficient of re-combination, is easily calculated. If we assume that the ions in hydrogen are charged molecules of hydrogen, the coefficient of re-combination at o° C. would be 1.5 X 10-; the value found by experiment is about 10-, hence we conclude that the hydrogen ion is more complex than the hydrogen molecule. The kinetic energy due to temperature is shown to prevent the ions getting very much larger than the molecules; thus if the radius of the molecule were 10-8 cm., the radius of the ion could not exceed 3× 10-.-Some physical properties of sodium vapour: P. V. Bevan. The experiments described in this paper were made to investigate the phenomena of the cloud of sodium vapour formed by heating a piece of metallic sodium in vacuo or in an atmosphere of hydrogen. In certain circumstances the sodium vapour forms a very sharply defined cloud with apparently a definite surface across which diffusion does not take place. The formation of this cloud, which was discovered by Prof. R. W. Wood, was found to be conditioned by the presence of water vapour in the atmosphere in which the sodium was heated. In vacuo the sodium vapour behaves like any other vapour, and in perfectly dry hydrogen there is no definite surface to the vapour observable when the sodium is heated. It was also shown that in vacuo the sodium begins to form vapour at the temperature of boiling water. The view is put forward that when the sodium cloud is seen on heating sodium in a vacuum tube the effect is due to the formation of an atmosphere of hydrogen occluded by the sodium and formed by the action of the sodium on sodium hydroxide.-A null method of measuring small ionisations : N. R. Campbell. Measurements have been made of spontaneous ionisations by adjusting the pressure of the air in a closed vessel containing a constant amount of uranium until the current through that vessel was equal and opposite to that through the spontaneously ionised gas. By this device certain difficulties connected with the measurement of capacity and the preservation of insulation are avoided. The reflexion of sound at a paraboloid: Rev. H. J. Sharpe.

DUBLIN.

Royal I ublin Society, April 18.—Prof. J. A. McClelland in the chair.-Notes on the constitution of nitric acid and its hydrates: W. Noel Hartley. The author referred to a paper by him published in 1903 in the Chem. Soc. Trans. on the absorption spectra of nitric acid in various states of concentration. He had assigned the formula H,NO, to normal nitric acid, and suggested that the several hydrates described were hydrates of this acid; but H. Erdmann, also in 1903, having isolated and described five nitric acids, the author was led to revise the formulæ of the hydrates in accordance with the constitution of these