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Alpha range. The change to hardenite is somewhat advanced when Ac 1 merges into Ac 2 at about 720° C. owing to these points always overlapping in the heating curve. The hardenite areas probably remain unchanged on the sites previously occupied by the pearlite until the Gamma range Ac 3 is reached (at about 810° C.), when the hardenite and ferrite dissolve into each other, forming a homogeneous molecular mixture. In a saturated steel there is, on heating, a single absorption of heat at the change point Ac 1, 2, 3, the amplitude of which ranges from about 710° C. to 730° C. This change marks the transformation of the whole mass from pearlite into hardenite. On cooling, there is a very considerable evolution of heat at the single point Ar 1, 2, 3, the amplitude of which ranges from about 690° C. to 660° C. This recalescence marks the transformation of hardenite into pearlite. The particular phase of pearlite obtained depends upon the rate of cooling from 660° C. to atmospheric temperature. The emulsified phase is produced by very rapid cooling, normal pearlite by ordinary cooling, and laminated pearlite by very slow cooling. Pearlite, in which the carbide is emulsified or 'sorbitic," may also be produced by tempering hardenite. The micrographic and thermal transformations of a supersaturated steel are as follows:-At Ac 1, 2, 3 the sectional ground mass of pearlite changes to hardenite, the cementite slowly segregates into larger masses until a temperature of about 900° C. is reached, then the cementite and hardenite dissolve one into the other, and a homogeneous mass of hardenite and cementite is obtained. On cooling, at about 900° C. the cementite falls out with a faint evolution of heat, and is completely segregated long before the point Ar 1, 2, 3 is reached, hence the micrographic transformations of cementite and hardenite are quite unconnected with the three thermal critical points or any of them, and are due entirely to the influence of temperature.

Mr. A. W. Richards and Mr. J. E. Stead, F.R.S., read a paper on overheated steel, describing experiments supplementing their previous work on the subject, and showing that re-heating overheated good steel can be relied upon to restore good properties to brittle material. Steel initially bad, brittle, and dangerous owing to irregularity in the distribution of the elements cannot, however, be made good by any kind of heat treatment.

Mr. L. Guillet (Paris) contributed a paper on the special steels used for motor-car construction in France. Steels with low percentages of carbon and nickel are used for parts which require case hardening and quenching. Steels with medium percentages of carbon and low percentages of nickel are used after quenching and re-heating for a large number of parts. Steels low in carbon and high in nickel are used for valves. Chromium steels with high carbon and low chromium are used for bearings. Silicon steels are used for springs and for gearing. Nickel chromium steels are used for numerous parts requiring resistance to shock.

Mr. Guillet also submitted an exhaustive paper on the use of vanadium in metallurgy. Vanadium improves the properties of alloys. In normal steel it increases the tensile strength and elastic limit, and in quenched steel it acts in the same way without increasing the brittleness. Vanadium is certainly the element which, together with carbon, acts with the greatest intensity in improving alloys of iron.

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The paper read by Mr. B. Talbot (Middlesbrough) on segregation in steel ingots was one of great interest, as, although attention has been directed to the effects of segregation, little has been published as means of lessening the amount of such segregation. The author's investigations, in which parallel tests have been made on ingots from the same heat with and without the addition of a small amount of aluminium, are of special value. The ingots were obtained from both acid and basic openhearth furnaces, and were 5 feet 6 inches in height, the drillings for analysis being taken over the whole surface of the divided ingot. When no aluminium was added excessive segregation down the central line of the ingot occurred from 6 inches from the top to about half way down the ingot. Sulphur is the element that tends to segregate most, phosphorus next, then carbon, and finally manganese. NO. 1875, VOL. 72]

With the use of aluminium, a billet of much more regular composition is obtained.

Mr. Douglas Upton (Jarrow) described an ingenious mechanical device for handling steel bars during the process of manufacture.

Mr. L. Dumas (Paris) read a lengthy paper on the reversible and irreversible transformations of nickel steel. The starting point of the investigation was Prof. John Hopkinson's well known experiment in 1889. Nickel, manganese and carbon, introduced into a steel, the author finds, determine alike the appearance of the same phenomenon, irreversible transformation, which is the more intense the higher the proportions in which they are present. They must also be in solution, a state which is often, as regards carbon, impossible of attainment without the aid of chromium. The nickel steels which have not undergone transformation, although too costly to be of industrial use, are of great interest as showing the result of adding nickel to steel. The homogeneity is increased, and the proportion of B-iron intensified.

Mr. G. B. Waterhouse (New York) submitted a paper giving the results of the investigation of a series of steels of constant nickel with varying carbon percentages. The results showed that nickel raises the tenacity without materially lowering the ductility. Annealing lowers the tenacity without greatly raising the ductility. lowers the transformation points Ar 3, 2 and Ar about 20° for every 1 per cent. of nickel.

Nickel

Captain H. G. Howorth, R.A., contributed a paper on the presence of greenish coloured markings in the fractured surfaces of test-pieces. The attention of the Ordnance Committee was directed to defects of this kind in testpieces from tubes for guns, and the object of the paper was to ascertain to what extent the presence of such defects should weigh in accepting or rejecting the forgings for this purpose. The flaws appear to be due to slag, and in any forging subject to violent alternating stresses these flaws in prolongation may easily develop into cracks. Interesting contributions to the discussion were made by General O'Callaghan, president of the Ordnance Committee, and by General Sir J. Wolfe Murray, Master-general of the Ordnance.

Mr. Thomas Andrews, F.R.S., contributed a paper on the wear of steel rails on bridges. He received from a railway company the fractured portions of an acid Bessemer steel rail which had broken in main line service after eleven years and five months' service on a bridge. It had borne 148,000,000 tons of passing traffic, and had lost 0.69 lb. per yard per annum in weight. One of the chief causes of the fracture has been the defective segregated chemical composition of the rail. The percentages of combined carbon and manganese, found in the top of the rail head and in the bottom flange, were in excess of what should obtain in good rail steel. The chemical composition was an undesirable one, and such as is liable to lead to brittleness and sudden fracture in rail service. The highpower microscopic examinations confirmed the results arrived at by the chemical analyses and physical tests, and they demonstrated the non-uniformity of the physical and crystalline structure of the rail. The microscopic examinations have also shown the undesirability of employing rails having too high a percentage of combined carbon and manganese, and they have indicated that great care should be exercised in the thermal treatment of rails, from the ingot to the finished rail, in order to obtain a suitable microcrystalline structure resulting in a good durable rail. The existence of troostite can no longer be questioned, but opinions as to its divided. Dr. C. Benedicks (Upsala), in a paper on the subject, expressed the view that troostite is a pearlite with ultra-microscopically small particles of cementite. In all probability troostite is formed by a transformation in situ of martensite.

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Prof. E. D. Campbell (Michigan University) contributed' a paper on the occurrence of copper, cobalt, and nickel in American pig-irons. The percentages varied in the specimens analysed from 0.011 to 0.039 of copper, from a trace to 0.048 of cobalt, and from a trace to 0.072 of nickel. The only two irons containing any considerable amount of cobalt and nickel possess valuable properties for car-wheel castings.

ELECTRONS AND MATTER. THE inaugural address on "Electronen en Materie,"

delivered by Prof. C. H. Wind upon taking the chair of mathematical physics and theoretical mechanics at the University of Utrecht on February 20 of this year, has lately been published (Leyden: A. W. Sijthoff). Beginning with a brief account of the gradual development of the conception of electrons, mainly through the works of H. A. Lorentz, and of its sudden corroboration after the discoveries made by Zeeman and Röntgen, the address goes on with an exposition of the notions of ether, electric displacement, electrons, and magnetic force in their present form, and traces the way to the idea of an electromagnetic mass of the electrons.

The measurements made by Kauffmann, though showing that these particles of matter probably do not possess any mass besides this electromagnetic one, of course do not prove that the same should be the case with all other particles of matter in our universe, as Wien had suggested. Yet they make this suggestion-the basis of what the author calls an electron theory à outrance-to some extent a plausible one. Several of the brilliant and fascinating views which this ultimate theory opens having been expounded by Mr. Balfour in his presidential address at the Cambridge meeting of the British Association, the present author directs attention to those concerning the structure of atoms, mechanism of radiation, and origin of chemical differences. He also enters into some more details, and, assuming for a while that an atom of hydrogen consists of a single positive and a single negative electron, calculates that in this system the two components would be separated by a distance perhaps 100,000 times greater than the diameter of the largest of them, and that there must be stored up in the atoms constituting one gram of hydrogen an amount of energy equivalent to that required by a mail steamer to cross the Atlantic ten times.

Poincaré has raised several serious objections against the theory. Some of these relate to the temperate electron theory only, and lose their weight as soon as the ultimate theory is adopted. To take an example. Poincaré does not feel satisfied with the changes of length in solid bodies owing to their motion through ether, as suggested by Lorentz and by Fitzgerald in order to explain the result of Michelson's experiments. Lorentz himself, however, has already shown that this hypothesis, though appearing rather bold at first sight, becomes plausible as soon as molecular forces and masses are supposed to be in the same way as electromagnetic ones affected by a translation through ether; and it is clear that this supposition is involved in that of all matter consisting of electrons, which therefore at once clears the way.

The second category of objections, those arising from the dependency of electromagnetic mass upon velocity and direction of motion, from so many instances of unequal action and reaction, from the violation even of the law of inertia, whenever electrons move with a higher speed than light, are, on the other hand, most serious in the light of the ultimate electron hypothesis, whereas the temperate theory has a way left open to dispose of them. The latter theory, indeed, does not deny the existence of matter apart from electrons, and considers electromagnetic mass as something secondary. By assuming as stituents of ether hidde:: natter, obeying the classical principles just as well as ordinary or coarse matter, this theory will be able to account for every apparent deviation from the principles which by mathematical reasoning should be deducted as occurring in ccarse matter.

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But if by progress of experiment and theory the electron hypothesis in its ultimate form should continue to gain ground if it should finally prove unavoidable to accept the view that matter consists entirely of electrons, then mass and momentum would cease to be what they are now in our ideas, quantities strictly invariable. There is no denying that this would involve a serious change of our general conception of nature. For the predilection and confidence with which science has for centuries been aiming at a description of the physical universe in terms only of matter and motion were based chiefly-though half unconsciously on the idea of mass and momentum being invariable elements of nature, images or pictures of in

variable elements of reality itself. Now this idea, s fundamental to our whole mechanical conception of nature, would shrink into an illusion in the light of the new theory. Of course, there would be a great advantage also. Whereas it seems now almost hopeless to involve electromagnetic phenomena in a description in terms only of matter and motion, the unity desired in our picture of the physical world would then be secured by putting it in terms of electrons and motion.

UNIVERSITY AND EDUCATIONAL

INTELLIGENCE.

WE learn from Science that an anonymous gift has been made to the Lebanon Valley College, Annville, Pa., of a hall of science to cost 16,000l.

MR. F. R. B. WATSON has been appointed assistant lecturer and demonstrator in engineering at the Merchant Venturers' Technical College, Bristol.

A REUTER message from New York states that the American General Education Board has received from Mr.

John Rockefeller cheques to the amount of 2,000,000l., in pursuance of his promise last June to give that amount in cash or securities for the endowment of higher education.

A PRIZE of 5ol, out of the Gordon-Wigan fund will be awarded at the end of the Easter term, 1906, for a research in chemistry, of sufficient merit, carried out in the University of Cambridge. The research may be in any branch of chemistry. The dissertation, with the details of the research, must be sent to the professor of chemistry nud later than the division of the Easter term, 1906.

THE year-book of the faculty of engineering of the University of Liverpool (1905-6) shows that the courseof study are so arranged as to afford a general scientific training for those intending to become engineers. The honours course affords opportunities for specialisation in a selected branch of the profession. The university training. which extends over three years, is preliminary to or sup plementary of pupilage under an engineer or apprentic ship with an engineering firm.

IT is announced in Science that the University of Pennsylvania will receive 12,000l. from the estate of the late Prof. Maxwell Sommerville, who held a chair of archæology in the university. President Thwing, of Western Reserve University, we learn from the same source, has announced that Mr. Andrew Carnegie has given 5000l. towards the establishment of a fund 20,000l. for the endowment of a chair of political ecoñones at Western Reserve University, to bear the name of the late Senator Hanna.

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THE Engineering and Mining Journal publishes the presidential address delivered by Mr. F. W. McNair before the Society for the Promotion of Engineering Education, in which he shows that the American mining schools have amply proved the necessity for their existence. From statistics of the six largest mining schools in America, he shows that the ratio of graduation to enrolment is increasing, that there is an enormous percentage increase in students enrolled, and that the mining school product is gradually taking the place of the so-called practical man. Dividing the twelve years available for comparisca into three periods of four years, it is shown that the schools under consideration graduated one man to 136 million tons of the total mineral production during the first period, one to 10-2 millions in the second period, ami one to 9.4 millions in the last period.

IN connection with the department of geography of the University of Cambridge, special public lectures will t delivered in the Michaelmas term by Sir Clements R. Markham, K.C.B., F.R.S., and Sir Archibald Gekie. F.R.S. The following courses, which are open to all students, whether members of the university or пог have also been arranged :-A general course in geography (with practical work) will be given by Mr. H. Yule Oleham; courses on the geography of Europe, on the prin ciples of physical geography, and on the history geographical discovery will also be given by Mr. Oldham. Dr. J. E. Marr, F.R.S., will lecture twice weekly on geomorphology; Dr. A. C. Haddon, F.R.S., will gove courses on ethnology and on anthropogeography; and Mr

A. R. Hinks will lecture on geographical surveying (with field work). The duties of the board of geographical studies, which is responsible for the general administration of the department, include the promotion of geographical study and research within the university, the provision of instruction in the several branches of geographical science, the administration of the geographical education fund, and the publication of schedules defining the range of the geographical examinations for degrees and diplomas of the university in geography.

THE development and strengthening of the relation which the work of technical institutes and evening classes bears to the practice and commercial aspects of our industries are undoubtedly necessary parts of further industrial progress. For this reason we welcome a recent circular issued by the Board of Education to the inspectors of these educational institutions. The Board recognises the existence of a great variety in the character and amount of the cooperation between employers of labour on the one hand and the managers of technical institutions and evening schools on the other, and in its circular gives a short account of a few typical examples with a view of showing inspectors and others the kind of work which can be done with advantage in this direction. It is true that the details of such cooperation must vary from place to place in accordance with the special requirements of each important industry, but unless it exists in one form or another full advantage will not be derived from our expenditure on technical education. The circular proceeds to give a helpful résumé of what has been done to encourage artisans in their studies by means of the payment of fees and the award of prizes, by increases of wages, by allowances of time for attendance at classes, and by providing opportunities for higher instruction. The circular may be commended to all employers of labour who desire that the workmen of this country may be put into the way of competing on equal terms with those of other countries.

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ON Friday last Lord Rosebery, as Chancellor of the University of London, opened the Goldsmiths' College at New Cross, formerly the Goldsmiths' Institute. The development of Polytechnics under the London County Council led the Goldsmiths' Company to reconsider the constitution of the institute, which had been carried on by the company since 1888; and last year the buildings were presented by the company to the University of London, with an occupied adjoining site of four and a half acres, and an endowment of 5000l. a year for five years. An additional sum of 5000l. was given by the company to enable the university to carry on evening classes during 1904-5, in cooperation with the London County Council. Under the new scheme the institution has become the Goldsmiths' College, University of London, and its functions are chiefly those of a day training college for elementary teachers. These students will take the ordinary two years' course provided by the regulations of the Board of Education, and will not prepare for a university degree; but the evening class work in science and engineering will still lead up to university degrees. In the course of his remarks at the opening ceremony, Lord Rosebery said :-" The University of London is spreading itself over the metropolis. It is not too much to say that, though we cannot say that it will soon spread itself over the Empire, we may at least say that it will very soon appeal to every portion of the Empire. It is a young university. It deals with comparatively new branches of learning. It deals with the practical and the concrete, rather than with the ancient and the abstract. In that respect there is a marked difference between it and those ancient universities to which some of us owe a loyal and filial allegiance which cannot be obliterated by any newer loyalty or allegiance. The newer universities must be content, and wisely content, with something which is not antiquity, and is not tradition, but may be more immediately useful and practical than either antiquity or tradition. We, placed in the largest community in the world, with our hands, so to speak, on the very heart of the Empire, living among new wants and new aspirations, meeting new needs and new acquirements, ready, as I hope, to face the exigencies of to-day and tomorrow, are the university of the future, though we cannot trace our antiquity back to the hoary past.

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The corresponding ketone may be prepared by acting upon chloracetylcatechol with methylamine, and is a crystalline substance forming stable crystalline salts. The ketone may be reduced electrolytically, and the product may have the structure assigned to natural adrenalin. Although the synthetical base has many chemical and physiological properties in common with adrenalin, it probably is not the racemic form of the latter substance. The base forms extremely deliquescent salts which are unstable in hot solution; on addition of ammonia to aqueous solutions of the salts, the free base is precipitated in the form of a greywhite amorphous precipitate which is extraordinarily unstable in the dry state. Owing to experimental difficulties, satisfactory analytical and molecular weight determinations have not yet been made.

A close physiological relationship between the natural and synthetical bases is shown by the fact that, in the case of a rabbit, intravenous injection of less than 0.000001 gram is followed by a marked rise in arterial blood-pressure.

A base which is probably identical with the substance above described has been obtained by acting upon methylaminoacetylcatechol with aluminium and mercuric sulphate (D.R.-P. 157,300), and it is assumed to be a secondary alcohol. If this be correct, the formula for natural adrenalin will require modification, but more experimental evidence is needed before the question can be settled.

July 1. On the Influence of Collisions and of the Motion of Molecules in the Line of Sight, upon the Constitution of a Spectrum Line.” By Lord Rayleigh, O.M., F.R.S.

Apart from the above and other causes of disturbance, a line in the spectrum of a radiating gas would be infinitely narrow. A good many years ago, in connection with some estimates by Ebert, the author investigated the widening of a line in consequence of the motion of molecules in the line of sight, taking as a basis Maxwell's well known law respecting the distribution of velocities among colliding molecules, and he calculated the number of interference bands to be expected, upon a certain supposition as to the degree of contrast between dark and bright parts necessary for visibility. In this investigation no regard was paid to the collisions, the vibrations issuing from each molecule being supposed to be maintained with complete regularity for an indefinite time.

Although little is known with certainty respecting the genesis of radiation, it has long been thought that collisions act as another source of disturbance. The vibrations of a molecule are supposed to remain undisturbed while a free path is described, but to be liable to sudden and arbitrary alteration of phase and amplitude when another molecule is encountered. A limitation in the number of vibrations executed with regularity necessarily implies a certain indeterminateness in the frequency, that is, a dilatation of the spectrum line. In its nature this effect is independent of the Doppler effect-for example, it will be diminished relatively to the latter if the molecules are smaller; but the problem naturally arises of calculating the conjoint action of both causes upon the constitution of a spectrum line. This is the question considered by Mr. C. Godfrey in an interesting paper, upon which it is the principal object of the present note to comment. The formulæ at which he arrives are somewhat complicated, and they are discussed only in the case in which the density of the gas is reduced without limit. According to the view of the 1 Phil. Mag., vol. xxvii., p. 298, 1889; "Scientific Papers," vol. iii, p. 258. On the Application of Fourier's Double Integrals to Optical Problems," Phil. Trans., A, vol. cxcv., p. 329, 1899.

present author, this should cause the influence of the collisions to disappear, so that the results should coincide with those already referred to where the collisions were disregarded from the outset. Nevertheless, the results of the two calculations differ by 10 per cent., that of Mr. Godfrey giving a narrower spectrum line than the other.

The difference of 10 per cent. is not of much importance in itself, but a discrepancy of this kind involves a subject in a cloud of doubt, which it is desirable, if possible, to dissipate. Mr. Godfrey himself characterises the discrepancy as paradoxical, and advances some considerations towards the elucidation of it. The present author has a strong feeling, which he thinks he expressed at the time, that the 10 per cent. correction is inadmissible, and that there should be no ambiguity or discontinuity in passing to the limit of free paths infinitely long. In connection with some other work he has recently resumed the consideration of the question, and he is disposed to think that Mr. Godfrey's calculation involves an error respecting the way in which the various free paths are averaged. A discussion of the subject is given in this paper.

PARIS.

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Academy of Sciences, September 25.-M. Trost in the chair. On the origin of the principle of virtual displacements: P. Duhem. Descartes proposed to found his system of statics on the proposition It requires the same power (puissance) to raise a given weight a fixed height as to raise a weight K times as great to a height K times less.' M. Duhem has found that this principle was first implicitly used by Jordanus de Nemore, in his Tractatus de ponderibus, dating from the thirteenth century, and traces its use by various writers down to the time of Descartes in 1637.-Observation of the total eclipse of the sun of August 30, made at Robertville, Algeria: M. Salet. The plan of work included (1) a search for the existence of a magnetic field in the neighbourhood of the sun by the observation of the deviation of the plane of polarisation of the coronal light; (2) the photographic study of the distribution of the polarised light of the corona; (3) the study of the atmospheric polarisation; (4) the spectropolarisation of the corona; and (5) the photography of the ultra-violet spectrum of the corona. A résumé of the results, which were successful, is given.-On the observations of the total eclipse of the sun of August 30 made at Guelma by the commission from the Observatory of Algiers: Ch. Trépied. The results obtained include the confirmation of the supposed relationship between coronal structure and the state of solar activity, the photographic impression of the moon's disc on the corona apart from totality, the photographic registration of a very curious phenomenon of elliptical rings, and negative exposed during the whole of totality permitting of the study of the greatest photographic extension of the corona during this eclipse and of contributing to the elucidation of the question of the intraMercurial planets.-New researches on the reproductive apparatus of the Mucorineæ: J. Dauphin. The formation of the mycelium has been followed with the microscope, day by day, up to the production of the reproductive organs. The effect of varying the nature of the carbohydrate present in the culture medium was studied, and observations made with raffinose, dextrin, starch, dulcite, erythrite, glycerin, ordinary alcohol, salicin, and quercite.-On the sensibility of the chlorophyll apparatus in ombrophobe and ombrophile plants: W. Lubimenko. The facts observed show clearly that the assimilating energy depends on the concentration of the pigment in the chlorophyll grains. The curve representing the assimilating energy may, according to the concentration of the pigment, rise to the upper limit of the natural radiation, as in ombrophobe plants, decrease before this limit, as in ombrophile plants, or may remain stationary, starting from a certain intensity, as in the yellow leaves of Taxus.-Spontaneous vegetation and the wholesomeness of drinking water: L. A. Fabre.

GOTTINGEN.

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Royal Society of Sciences.-The Nachrichten (physicomathematical section), part iii. for 1905, contains the following memoirs communicated to the society:February 25. A. Sommerfeld: The electron theory,

iii.; on electrons with velocities equal to or greater than the velocity of light. H. Happel : On the equation of condition of monatomic substances.

May 20.-W. Holtz: How rotation can begin in a planetary nebula. W. Holtz: The reason for the starshaped appearance of the stars. C. Runge: On the numerical solution of total differential equations.

June 3.-H. Gerdien: A new apparatus for the measurement of the electrical conductivity of the air. H. Gerdien Measurements of the density of the vertical electrical conductive current in free air during the balloon ascent of May 11, 1905.

June 24-Wilhelm Blitz: Contributions to the theory of "lakes" in dyeing.

The Business Notices, part i. for 1905, contains a repor on the Samoa Observatory, a long obituary notice of Ernst Abbe by Prof. Voigt, and an appreciation of Georg Meissner by Prof. Max Verworn.

NEW SOUTH WALES.

Royal Society, August 2.-Mr. H. A. Lenehan, president. in the chair.-The refractive indices, with other data, o the oils of 118 species of Eucalyptus: H. G. Smith. In this paper the author records the refractive index, the specific gravity, the specific refractive energy, and the solubility in alcohol of the oil of each species. The material was distilled at the Technological Museum, Sydney, and most of it had been prepared for the work Research on the Eucalypts and their Essential Oils,' by Mr. R. T. Baker and himself. The oils of those species which have been obtained since that work was published are also included.

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Garry: "Notes on the Drawings for Sowerby's
English Botany.'”—B. D. J.

Wells A Text-book of Chemical Arithmetic."
A. S.

Byrom: "The Physics and Chemistry of Mining"
Letters to the Editor:-

On the Absorption Spectrum of Benzene in the Ultraviolet Region.-Prof. W. N. Hartley, F.R. S. Rhymes on the Value of .-F.R.S.

The Celtic Pony.-Dr. Francis H. A. Marshall Greek Archæology. (Illustrated.) By H. R. Hall South African Meeting of the British Association Two Reports of the French Glacier Commission. By E. J. G.. International

Innsbruck

Meteorological Conference at

International Union for Cooperation in Solar Re

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