摘要:

IF any apology were needed for our return to the third volume published by the Committee on Industry and Trade,' we would refer our readers to the articles and reports dealing with education and industry which have appeared in our columns during the last two years or so. If those articles and reports be carefully scrutinised, it will be seen that we have attempted, very deliberately, to show not only the necessity, but also the origins, directions, and even deflexions of the rapidly growing tendencies towards a scientific view of education in relation to the structure of modern society. We venture to suggest, too, that our interpretation of the term ' scientific education ' has been wide and liberal enough to satisfy the most suspicious guardian of the delectably elusive qualities which are covered by the word ' culture.' Perhaps at another time we shall demonstrate the possibility of realising some of the classical ideals which are still inherent in the life of a commumty developing under an apparently grey and formless industrialism. In the meantime, the attitude of the present volume towards technical education has a special attraction from the point of view of its significance to the educational movements we have been observing. Whatever may be our notions of the contributions which are made towards the solution of the problems before the Committee, we believe that its attitude towards the relationship of technical education to industry will do much to strengthen that relationship, and so aid, not only in the industrial reconstruction which lies ahead, but also in the general intellectual progress towards a less anomalous civilisation than exists at present.It would be easy, perhaps, to criticise the chapter on technical education on certain grounds, the chief of which might be that it is based upon memoranda supplied by government education departments, and that it presents the usual shortcomings of memoranda from such sources, namely, a certain timidity and a platitudinous repetition of possible improvements. But it must not be forgotten that what is platitudinous to the expert may be illuminating and inspiring to the layman; and this volume is primarily for business men rather than for educationists. The charge of timidity, too, loses much of its power when we read the Committee's warning that the volume " is not concerned. with recommendations. Its aim is to assemble and analyse facts and tendencies, and by so doing to narrow the range of economic controversy and prepare the way for the intelligent study of the problems by which British industry is confronted." Three necessities are, however, made clear: expansion of the scope and number of technical classes; the better adjustment of their relationship with industry; and the constant need to adjust the relations of general and technical education.Further, if the Committee does not profess to give detailed recommendations, its survey of the present relationship of technical education to particular industries, and its suggestions as to possible improvements, will be greatly helpful to any national industrial organisation, group of employers, or individual employers. Clearly the Committee is doubtful whether full co-operation can be reached by local advisory committees alone. It realises that as yet there has been little serious study on the side of industry of the possibilities of a considered policy of technical school training for young employees; and it is certain that substantial improvements could be suggested if each industry would survey, from its own point of view, the existing facilities, see what gaps need filling and what developments are desirable, take an active interest in the schools and give effective assistance to their conduct. That assistance could take many forms. Lectureships could be founded or subsidised where the public provision is inadequate; grants to part-time teachers to help them to gain wider experience or to improve qualifications; scholarships to promising students; consideration of the methods of filling the more responsible posts; consideration of the number of men needed annually, and the kind of qualifications they should possess; allowance of ' time-off ' during working hours to students who have shown diligence and ability to profit by instruction in technical schools. Three other serious weaknesses of the present system are indicated. The connexions between universities and technical schools are accidental rather than systematic, even though some technical institutions are of university rank and function as technical universities. Premises, too, are unsatisfactory, and work is sometimes conducted " under conditions which are tolerated rather than approved." Finally, the training of teachers presents a difficult problem. Obviously men of experience and skill in trades and processes they teach are essential. But more than such experience and skill is necessary if the highest results are to be attained. Vacation courses have proved extremely valuable; but these, in themselves, are not sufficient. By what other means can this vital problem be settled ?The Committee's view of its problems is shown excellently in some passages which are worthy of reproduction: " The vitality of modern industry, like that of an organism, is measured by its power of response to external stimulus and of self-adaptation to modern environment. Mobility (in this sense of the term) does not imply incessant and purposeless movement or change. . . . But it does imply the power of spontaneous reaction to changes in economic conditions and of internal modifications and rearrangement to meet such changes. . . . It applies to modes of preparation for industry and the right adjustment between the functions of school education and workshop training which demand continual modification and re-adaptation both to fit the changing needs of modem largescale industry and to counteract some of the dangers of excessive sub-division of employments."Following this line of thought, the Committee does not fail to observe that in our age of flux and transformation, no plan of educational development can be justified which does not maintain unimpaired initiative, flexibility of temperament, powers of adaptation and capacity for co-operation among all the partners in production and distribution. Such a view ought to show very clearly to those who may be fearful, that mere vocational instruction is by no means what the Committee understands by the term 'technical education.' It would, after all, be too much to expect from a single committee and particularly from a committee with such wide terms of reference-a solution of the delicate, far-reaching, and manysided problems presented by an attempt to examine the relationship of technical education to industry. It must not be forgotten that other bodies are also making their contributions to these problems; and if we indicate only some of the activities which we have been observing, it will be sufficient to justify the remark we made above concerning rapidly growing tendencies."The Board of Education's Consultative Committee has presented its report on the education of the adolescent; a Committee on Education and Industry (under Mr. D. 0. Malcolm) has presented the first part of its report, and is preparing the second part; a Ministry of Labour Inquiry into the general question of apprenticeship is not yet completed; the League of Nations recently held a conference on conciliation in industry, and will shortly continue that conference at Geneva; finally, the committee brought into being by the many learned and professional institutions and teaching associations under the chairmanship of the late Lord Emmott, is now in the stages of compiling its report on the relationship of technical to other forms of education and to industry. When such activities are reviewed the importance of the present volume may be rightly judged, especially when it is recalled that the President of the Board of Education informed a deputation of the Emmott Committee, last May, that not until he had before him the reports of at least four of these bodies could he begin to formulate the changes which may be immediately necessary.The contribution of the present volume, too, falls further into its place when we note that it divides its educational problem into three main parts: industrial output is not a mere question of volume, but depends essentially on quality; under modern industrial conditions the relative range and potency of apprenticeship have tended to diminish; school education before entering, and concurrently with, employment has increased in importance. There is not yet any consensus of opinion, however, as to the mutual relations and limits of workshop training and school education, looked upon as complementary factors. In making its surveys of technical education and apprenticeship, the Committee hoped to be " of assistance in arriving at clearer views on this vitally important question." That the volume achieves that object is beyond all doubt.Committee on Industry and Trade. Factors in Industrial and Commercial Efficiency: being Part I. of a Survey of Industries. With an Introduction by the Committee. Pp. v+544. (London: H.M. Stationery Office, 1927.) 5s. net

ISSN:0028-0836    

DOI:10.1038/119517a0

出版商:Nature Publishing Group    

年代:1927

数据来源: Nature

摘要:

THIS is an able and interesting volume, in which there is at once great learning and considerable power of speculation. Prof. Catlin has an important thesis to maintain, and his urbanity of manner will not conceal from the reader that he is prepared to maintain his ground against all comers. The field, indeed, is already, as if in advance of conflict, strewn with the illustrious dead; at least I seem to discern there the scalps of Plato and Aristotle, Kant and Hegel, exposed as a warning to prospective combatants. In a sense, Prof. Catlin's book is difficult to review; for it is to be followed by a book already in preparation in which the thesis he here lays down is to be applied to our problems. Obviously, therefore, we shall not fully know what the method he advocates can do until he himself has applied it; and conclusions upon his analysis must be provisional until he has given us the full opportunity to see it at work. But as I understand his views, his purpose is to construct a science of politics which shall seek to do for man in society what the early economists did for the phenomena they survey. It will be abstract and deductive; it will have its axioms and postulates; and the test of its validity will lie in the verifiability of its predictions. Such a science, he argues, must free itself from the shackles which the historian and the philosopher have sought to impose upon it. For values it will have no concern. It will be concerned only with the observed behaviour of men. Assuming that there is a political man with the appetite for power, it will seek to construct the laws of his behaviour in adjusting means to purpose. With right or wrong it will have no more concern than the chemist with the moral qualities of hydrogen. It will be quantitative in character in that, upon the basis of its assumptions, it will seek from observation the largest possible number of examples from which to draw its conclusions. Having made abstraction of ethics, it will be able to approach the facts without a parti pris; and, instead of offering futile sacrifices upon the altar of teleology, it will be able to say (p. 199) that the " social situation only admits of certain appropriate measures." For studying what men do, it will be able to tell us what they will do; between the two Prof. Catlin injects a formidable therefore; and as this science of politics is refreshed by the constant accumulation of facts about the behaviour of men in their desire for power, as, also, such sister sciences as psychology contribute their due quota of knowledge, we may hope for the discovery of truths which will have value and influence of the same magnitude as those to which the economists have given birth.There is an air of promising certitude about these propositions, which have at least the merit of interesting audacity; though I observe with a little surprise that Machiavelli is appealed as their benevolent compurgator. For if ever a man had a definite end in view (which, as a passionate Italian patriot, he would have regarded as ethical), if ever, also, a man selected his facts to suit the thesis his experience dictated as best suited to his end, that man was Machiavelli. Perhaps the best thing one can do is to indicate, though with appreciation, some of the doubts to which Prof. Catlin's argument gives rise. The victories of economic science as built in terms of ' economic man' seem to me less outstanding than he claims, and its main successes have been won in spite of, rather than because of, its original and rigorous abstraction. The chief influence of the late Prof. Marshall, for example, was mainly due to the ingenuity with which he transformed the classic economics into something approaching the complexity of the facts; in no other way, moreover, could the economists answer the challenge of Marx, whose own 'economic man' led, by the technique of his construction, to quite different conclusions. Prof. Catlin, moreover, has a simple faith in facts as such, which, in the social sciences, at least, I do not find it easy to share. They are not born free and equal. The expert interpretation of a social environment is coloured by the personal equation of the observer in a way that is momentously different from an expert interpretation of a physical or chemical environment. What Mr. Justice Holmes has called the ' inarticulate major premiss' of the judiciary is, as a rule, the main clue to their decisions; and yet the best of judges usually believe that they are finding the law in an unbiassed and scientific way. Nor is this all. The maxim 'as men behave, so they will behave,' is, statistically, probably true in a static world; the trouble with this world is that the environment changes at a pace so rapid that the forms of behaviour in one place or period are no clue to those forms in another. I agree that most social situations admit only of certain appropriate measures. But the difficulty here (and I cannot find that Prof. Catlin deals with it) is that the measures have to be chosen in terms of an end deemed right or wrong. We are, in fact, at once outside the realm of scientific politics; for here we are dealing with argument that has reference to ethical value which Prof. Catlin deems irrelevant. I would venture here to add that if the 'political man ' were what he describes him to be, in any sense that can be called significant, he represents so small a proportion of mankind that prediction built upon his behaviour would be no clue to the general habits of men. I wish, indeed, that Prof. Catlin had given us some examples of the political 'laws' that his science would establish. Provisionally, at least, he still leaves me with the impression that Burke's ' little mirror of circumstances ' would be vital in the battle.Perhaps I may put my difficulty in terms of an analogy. The Common Law for long proceeded upon the assumption (akin in character to that of Prof. Catlin) that where there was no remedy there could be no wrong; and in order that it might be adequate and effective it was necessary to invent the remedies of Equity, which proceeded upon the assumption (akin to that of political philosophy) that wrongs as such were entitled to redress. My own conviction is that Prof. Catlin's science of politics would need a similar supplement. What seems to me really valid (and brilliantly demonstrated) in his book is its plea for the systematic collection of facts and the deliberate undertaking of experiment. We need, in fact, an inductive study of politics, based on quantitative tabulation, instead of deductions moulded from our private desires. To have shown with wit and point and learning how much might be expected from such a development is the very considerable service Prof. Catlin has rendered us.

ISSN:0028-0836    

DOI:10.1038/119519a0

出版商:Nature Publishing Group    

年代:1927

数据来源: Nature

摘要:

THE ever-growing output of research that Tmarks the progress of chemical science is reflected in the increasing size of the chemical journals; and the task of the researcher whose text-books these form becomes more onerous each year. The work is lightened by the publication of the Chemical Society's Annual Reports, and by the appearance from time to time of monographs dealing with the more important theoretical aspects of the problems under investigation, but the wealth of information 'tied up' in the experimental work of the original papers is not so easily rendered accessible. This difficulty has been partially solved by the compilation of such comprehensive treatises as Houben-Weyl's " Die Methoden der organischen Chemie," or Meyer's " Analyse und Konstitutionsermittlung organischer Verbindungen," and the first two of the three books under review are frank attempts on the part of the authors to provide for Englishspeaking chemists similar correlated information on definite problems connected with laboratory practice. (1) Mr. Bate seeks to give in a short and concise form the various methods available for the synthesis of organic compounds that may be of utility both to senior students and research chemists, and the present pioneer volume is concerned with the synthesis of derivatives of benzene. The subject is discussed in twelve chapters, each dealing, usually, with one type of reaction. Thus in the chapter on nitro compounds, the nitration of different types of compounds by means of nitric acid is described; then follows a description of other methods of nitration; of the conversion of amines into nitro compounds; of anomalous cases occurring in nitration; and finally, the effect on certain groups of the presence of the nitro group in the molecule is discussed. The text contains full references to the original papers and patents up to April 1925, as in very few cases is sufficient detail supplied to make the reader independent of the original memoir. The reviewer suggests that in a future edition the names of the investigators be given as well as the references, in order to facilitate cross reference to abstract journals; and also, that the present scanty index be considerably extended.The general arrangement of the book is excellent, the printing clear, and the text remarkably free from errors, but in a few cases confusion arises from the use of italics at the beginning of a paragraph for the introduction of a new main section, whilst a sub-section is placed under headlines in heavy type. Not a few formulae are faulty owing to the misuse of the dot and bracket; and the printing of such expressions as " to react the substance," and " the substance to be amidated," and " oxy " for " hydroxy," are not pleasing to the English ear. These minor blemishes do not detract from the value of a book of such excellence that it should form a unique and most useful addition to the reference library of the organic chemistry departments of all university and technical institutions. (2) Prof. MacArdle's book is the first part of a treatise on the operative technique of synthetic organic chemistry, similar in a general way to the first sections of the well-known German works of Lassar-Cohn and of Weyl. The first chapter is devoted to " General Considerations," and treats of solution, methods of bringing about solution, choice of solvent, interliquefaction, crystallisation, solvent of crystallisation, and mixed crystals. In the following seven chapters the uses of the various types of solvents are discussed, the question of the purifying of the substance being treated critically and the fullest practical details being supplied. These chapters are rich in references to special cases in which the solvent in question has proved of unique value, and also of instances when anomalous reactions have occurred which limit the use of the solvent. The remaining two chapters are devoted to a consideration of "Special Means to Induce Crystallisation " and to "Salting Out "; a full bibliography and two exhaustive indexes are appended.The arrangement of the book and the presentation of the subject leave nothing to be desired; for, in addition to its eminently practical value, the book is a readable one and holds the interest of the reader from the first page to the last. The statement on page 138 that the dangers attending the use of dimethyl sulphate have been very much exaggerated cannot be generally endorsed, for in the experience of the reviewer more than one case of serious and prolonged indisposition has resulted from the use of this substance without special precautions being taken to remove all vapours in an effective draught.(3) The last of the three books with which this review is concerned differs widely in scope and purpose from the others. It is the fifth volume of " An Annual Publication of Satisfactory Methods for the Preparation of Organic Chemicals "; and indeed so eminently satisfactory are the methods described therein that the issue of the yearly volume marks a red letter day in the organic laboratory. Since the publication of the first volume, when the editors invited the co-operation of other organic chemists, the response has become wider each year, and in this volume twenty-four of the thirty-three preparations have been submitted by eighteen contributors.

ISSN:0028-0836    

DOI:10.1038/119520a0

出版商:Nature Publishing Group    

年代:1927

数据来源: Nature

摘要:

N ORTH-EASTERN Asia has entered the field 1N as one of the competitors with southwestern Asia as the home of man. The discovery of some fossil vertebrates that are common to Europe and western America but are absent from eastern America led Prof. H. F. Osborn in 1900 to predict that these animals had developed in northern Asia and thence migrated eastward into Europe and westward into America. The ocean they crossed was therefore the Pacific and not the Atlantic. Faith in this theory led Dr. R. C. Andrews to organise an expedition to search for the remains of these animals in the steppes which they must have crossed during their migration from inner Asia to the Rocky Mountains. The generosity of American patrons of science provided £50,000 for the purpose, and Dr. Andrews led to Mongolia a series of well-equipped expeditions which there made several sensational discoveries. The most dramatic was the finding of the eggs of Cretaceous dinosaurs. They were found in such abundance in one locality that one Mongolian woman brought in fragments of egg-shells in tinfuls. The eggs belong to three genera, one of which, Protoceratops, is a primitive form of the Ceratopsidoe. Dr. Andrews describes this locality as a dinosaur incubator, and he attributes its selection as the breeding-ground to the nature of the sand, which would have formed comfortable nests. Of still greater importance was the discovery, also in the Middle Cretaceous beds, of some mammal skulls. The first found had been sent to New York as a reptile, and recognised by Dr. W. D. Matthew as a primitive mammal. Stimulated by his report of the importance of the discovery, the search was renewed and other specimens found-. A preliminary account of the skulls is given in the volume, but a more detailed account has been recently published elsewhere. The expedition also discovered a series of important Eocene mammals. The first of the vertebrate fossils found by the expedition were some bones of the Baluchitherium, an Oligocene mamma], which was discovered by Cooper in northern India. The expedition found later a skull and a skeleton of this mammal, and Dr. R. C. Andrews was led by the discovery to the expectation that, as the human family probably began to diverge from the ordinary primates in the Oligocene, the remains of some primitive ancestors of man should be found in Mongolia. Large numbers of stone implements were found; they represent two periods-Neolithic and Upper Pal.Tolithic. The age of the latter is suggested as Azilian. Some members of the expedition were at first under the impression that the rough stone cores represented a pre-Chellean culture; but ultimately they were convinced by the large series collected and arranged by the archeologist, Mr. Nelson, that the cores were the residue of Upper Palholithic flaking. Nothing human was obtained by the expedition earlier than the Mousterian, of which implements have already been found in China, in the valley of the Hoang-ho. While the paleontologists were excavating the fossils, the two geologists with the expedition-Prof. Berkey and Mr. F. K. Morris-surveyed the area, worked out its history, and thus made a valuable contribution to Asiatic geology. Amongst other points of interest they find that there is no evidence of glaciation in the district, except in some small corries on the highest hills.The volume tells the narrative of the expedition. It is graphically and racily written, and gives a delightful picture of a group of men in cordial co-operation and all enthusiastic in their work. Probably in the effort to be popular the author constantly states the age of the beds in years, reporting, for example, that the earlier implements date from 40 thousand, and the later from 15 thousand years ago; such estimates are about as useful as if a historian tried to date an Act of Parliament by reference to the birth of John Smith. The book is well illustrated by photographs showing the expedition at work and the nature of the country, and by ideal pictures of the fossils skipping about in their native haunts

ISSN:0028-0836    

DOI:10.1038/119521a0

出版商:Nature Publishing Group    

年代:1927

数据来源: Nature

摘要:

To those who have used this work of reference, the new issue requires no commendation. For those who have not yet handled it, emphasis may be laid on the words from the title-page: "Compiled from Official Sources." The information provided as to the titles, addresses, officers, and activities of the scientific and learned societies and Government institutions in Great Britain and Ireland has been obtained from officials of the societies concerned, so the volume serves as a directory. In addition, the lists of authors and titles of papers presented before each society during 1925 gives some indication of the amount and direction of progress made in science and the arts. Take, for example, the Royal Society: the total number of papers, 226, shows great activity in the scientific world, while the fact that nearly three-quarters of them were published in Series A of the Transactions or Proceedings testifies to the fertile field of the mathematical and physical sciences. The various societies are grouped according to the subjects of their interests, beginning with those dealing with science generally. As regards classification, there will obviously be differences E of opinion; we think, however, that the Rontgen Society would be better in the Physics Section I than under Chemistry and Photography, while the Spelaeological Society (University of Bristol) is certainly archaeological rather than biological. The index, however, soon smooths out little difficulties of this kind. The new address of the British Cast Iron Research Association, at 24 St. Paul's Square, Birmingham, was probably announced too late for insertion. We are still of the opinion that all the research associations in Great Britain now in existence should be included and indexed under ' Research.' Some of the more recently formed scientific bodies have not yet appeared in the volume, but meanwhile we must be grateful for the valuable collection of data with which the publishers of this-annual continue to supply us.

ISSN:0028-0836    

DOI:10.1038/119522a0

出版商:Nature Publishing Group    

年代:1927

数据来源: Nature

摘要:

THE first article on the speed and height of the flight of birds is a very brief account of the subject. In the second one, on the respiration of insects (about 80 pages), the function of the spiracles and the movements which ventilate the tracheae are discussed, and the principal methods for investigating the movements are described and illustrated. Due attention is given to the physical and chemical aspects of the problem, e.g. the technique of gas microanalysis. The third article discusses the flight of insects and of birds and the methods which have been employed in the elucidation of the movements and of their mechanics.

ISSN:0028-0836    

DOI:10.1038/119523c0

出版商:Nature Publishing Group    

年代:1927

数据来源: Nature

摘要:

IN the Journal and Proceedings of the Asiatic Society of Bengal (vol. 8, No. 9; 1912) there is a paper by Dr. L. L. Fermor entitled “Preliminary Note on the Origin of Meteorites.”In approaching his subject Dr. Fermor deals with the effects of pressure in determining the mineral constitution of rocks. He refers especially to the case of eclogite, wherein the development of garnet, and occasionally of diamond, is remarkable. The first represents the allocation of the normal elements present in a gabbroid magma in such a manner as to give rise to the development of minerals possessing the maximum density; the second, the same effect in the relatively rare case of carbon being present. He instances the well-known occurrence of both diamond and garnet in certain eclogites of South Africa. Dr. Fermor concludes that there must be what he calls an infra-plutonic zone deep in the earth's surface materials, and probably extending far downwards, composed of rocks of eclogitic type and, probably, at such a temperature as maintains them in a plastic-solid state. He explains the occasional appearance of this infra-plutonic rock at the surface as due to special conditions whereby cooling forestalls the effects of reduction of pressure during the ascension of the rock; which in this way attains a region of negligible pressure while preserving a mineral structure proper to very great depths. The well-known kelyphite rims, sometimes surrounding the garnets of eclogites, indicate a partial break-down into mineral structures of lesser density. The recent results arrived at by Dr. Harold Jeffreys (NATURE, Sept. 25, 1926), based upon the velocity of transmission of compressional seismic waves, point to the existence of a zone of the density of basaltic glass underlying the granitic continents; the basaltic zone being succeeded downwards by one which Dr. Jeffreys suggests may be dunite. The granitic layer may possess an average thickness of from 20 km. to 30 km. The basaltic zone may have a thickness of about 20 km. The underlying layer may extend to a depth of 1500 km.Daly has contended for the existence of a general basaltic layer extending beneath the continents and oceans. Other eminent petrologists have held this view. We desire here, in the first place, to cite some recently added evidence in its favour. Washington's discovery of the chemical resemblance of the plateau basalts ejected at various times and at different points of the earth's surface, might in itself be regarded as conclusive. The resemblance, however, seemed to fail respecting the radioactivity of the rocks; the Oregonian basalt showing a much higher radioactivity than the Deccan and Hebridean (Phil. Mag., Nov. 1924). However, we pointed out at the time that the authenticity of our 'Oregonian' material was not perfectly assured. Thanks to the courtesy of Prof. Daly, Prof. Landes, and Prof. W. P. Smith, we have been able to examine specimens of Oregonian basalt of undoubted authenticity, and even a fragment from the specimen chemically investigated by Washington. The average radium and thorium contents of Oregonian rocks from twelve localities come out as closely alike with those already determined for the Deccan and Hebridean areas. Those who are inclined to limit radioactivity to local conditions will find it difficult to explain away the chemical and radioactive similarity of these enormous and widely sundered outpourings. Coming now to the third terrestrial layer-the high-density medium underlying the basaltic-it appears that there is no necessity, so far as seismic evidence is concerned, to suppose this layer to differ from the basaltic save in the matter of its mineral structure. The gabbros and the eclogites are magmatically the same. We have found that an eclogite possessing the density 3-415 yielded upon fusion a glass which when cold possessed a density of 2-746, which agrees with the results obtained by Day, Sosman, and Hostetter (Am. Jour. Sci., 37,1914) for the density of basaltic glass. The density of eclogitethe piezocrystalline form of the magma-would agree with the seismic evidence. It ranges from 3 2 to 3 5. That of dunite is 3-3. We see, then, that seismic evidence is not opposed to the simplifying assumption that the sub-continental materials as revealed in the plateau basalts may extend downwards to a depth approximating to 1500 km. In short, the assumption of the eclogitic character of the third terrestrial layer involves little more than the acceptance of Dr. Fermor's inference that the pressure conditions which convert carbon into diamond in eclogites is also responsible for the high-density mineral structure of these rocks.However, there is something more to be said. We have found recently that the eclogites possess on the average barely one half the radium and thorium contents of the plateau basalts. An explanation, we believe, can be offered for this apparently contradictory result; an explanation which, if it is correct, seems to throw light on the origin of terrestrial surface structure and surface history. Yet the explanation we would suggest is very elementary and simple. We assume that the outer material of the primeval earth was originally compounded of all those siliceous aggregates afterwards differentiated into the layers we have been discussing; and that it was not throughout uniform in chemical composition. There was heterogeneity on, probably, a very varied scale; in some places coarse, in others fine: and this heterogeneity of distribution and association affected the stable chemical elements as well as those that are radioactive. These assumptions seem to be the most general we can make as well as the most probable.Let us consider first the effects of heterogeneity in the distribution of radioactive elements. This would carry with it thermal heterogeneity. Some parts would melt before others, and when their surroundings were melted would retain a higher temperature and lower density. These parts would gravitate upwards. Again, some parts of lesser radioactivity would retain for longer periods the solid state. In the depths this condition would be especially effective, for here the pressure confers upon the medium the maximum density, as we have seen. Thus the temperature and pressure conditions conspire to preserve to, or confer upon, the medium a high density; and accordingly it gravitates downwards when the fusion of its surroundings permits. Hence it would come about that such gabbroid magma as was poor in radioactive elements-poor in uranium, in thorium, and in potassium-would retain the solid state longest and sink into the depths. It is a fact that eclogite is poorer than the plateau basalts in all three radioactive elements. Respecting potassium, the mean content of K2O in the five plateau basalts analysed by Washington is 0-89 per cent. The mean K20 content of seventeen eclogites cited by Rosenbusch is 0 70 per cent., and of eleven cited by Mile. Briere (Bull. Soc. Franeaise de Min., 43, 1920) it is 0-37 per cent. They are, in fact, at once the poorest in the heat-producing elements and the densest rocks known. There would, also, exist a lack of homogeneity respecting the distribution of the non-radioactive elements. Some parts would be richer in silica, alumina, etc.; others in metallic oxides, etc.; such parts would for ever seek to ascend or to descend. Or, in times of thermal loss, certain well-known factors concerned in magmatic differentiation would operate in the same directions.The final results should be precisely what we find; a highly siliceous and aluminous surface layer rich in radioactive elements and-what seismic evidence reveals-in the depths, rocks of maximum density and, as we now find, of minimum radioactivity. Should these inevitable final conditions be disturbed by the circulation attending a great revolution, they would gradually be re-established during the long later period of thermal loss. We perceive, in short, that heterogeneity in the circumstances is not stable, but must result in radioactive and gravitational stratification. Reversing our line of argument, we might justify our assumption of initial heterogey in recognition of the revealed surface structure of the earth.If these views are correct, it would appear that radioactivity mainly has been responsible for the stratification of the earth's outer materials. It has determined the origin of the radioactively rich and gravitationally light continental layer, of the isostatic layer of intermediate radioactivity and density, and of that more deep-seated layer which only at long intervals takes part in the great events of surface history: the major revolutions (" The Halley Lecture," 1924, pp. 31 et seq., and A. Holmes, Geol. Mag., July 1926). In short, it would appear to have fashioned those structural conditions which have been responsible for geological history and for the development of life upon the globe. Further evidence of stratification in the earth's great basaltic layer is revealed in the petrology of the oceanic islands. The island basalt-which we must regard as representing the same lava as composes the ocean floor or prevails immediately beneath it -is richer in all the radioactive elements, and at the same time lower in density, than are the plateau basalts. These island lavas reveal, in fact, the final differentiation of the substratum where it attains the surface of the globe; a differentiation referable to physical causes similar to those we have referred to above.As bearing on all our views of earth-history we would point out that the low radioactivity of eclogite directly affects estimates of geological time based upon the period required to bring about a major revolution. The length of previous estimates will require to be doubled.

ISSN:0028-0836    

DOI:10.1038/119524a0

出版商:Nature Publishing Group    

年代:1927

数据来源: Nature

摘要:

I THINK that all those who have worked on the spectrum of the aurora will congratulate Prof. Vegard on the notable success he has achieved in photographing so distinctly the line or band about λ5238 as recorded in his letter in NATURE of Mar. 5, p. 349. The technical difficulties which he had to overcome were formidable.The present letter is not written in an unsympathetic spirit, but it seems worth while to point out that an interpretation alternative to that of Prof. Vegard is possible. He identifies the band with one which he has observed in the phosphorescent spectrum of frozen nitrogen. But there is a band in about the same position in the negative band spectrum of gaseous nitrogen. Angstrom and Thalen (quoted by Kayser in " Spectroscopie ") gave the wave-length as x5227-5. The stronger bands of the same series come out with great intensity on Prof. Vegard's photograph as on other photographs of the auroral spectrum: so that it is probable, indeed nearly certain, that a long enough exposure would bring out this band. If, as would appear from Prof. Vegard's letter, precise wave-length comparisons are not feasible, the criterion of intensity distribution remains. I hope Prof. Vegard may think it worth while to photograph this negative nitrogen band with the same instrument, for direct comparison with the auroral spectrum. It is not unlikely that this would help a decision

ISSN:0028-0836    

DOI:10.1038/119525b0

出版商:Nature Publishing Group    

年代:1927

数据来源: Nature

摘要:

THE following few lines give a necessary elucidation to my critical note and to the answer given by Messrs. H. B. Baker and H. L. Riley (NATURE, Mar. 5, p. 348). My principal first theoretical argument is based on theinterdependenceof the atomic weights of the elements silver, nitrogen, and chlorine, resulting from the classical life-work of Richards and his school, in which I have the greatest confidence. If the atomic weight of silver = 107.876, then nitrogen = 14.006±0.0011, and chlorine = 35.456±0.002, most probably 35.458. If we accept Baker and Riley's value, silver = 107.864, then nitrogen would become 13.999, a value exceedingly improbable, especially having regard to the fact that Baxter found recently (Proc. Amer. Acad.,12, 12, p. 699, Dec. 1926) by an extremely careful physico-chemical research the value N = 14.006(7), which confirms the higher atomic weight of silver, namely, 107.876. This important argument was not referred to by Messrs. Baker and Riley.My second, no less important, practical argument was based on the assumption that Messrs. Baker and Riley have lost exceedingly small quantities of silver vapour on fusing the metal in hydrogen, so that the atomic weight found by them is slightly lower than the true one. They did their best to convince themselves that no visible condensation of metallic silver could be observed in their tubes, and they say that they have begun a new series of experiments to investigate the volatility and condensability of silver. I beg to remark that some experiments on a large scale in this directi6n were published by J. S. Stas so long ago as 1865 ("CEuvres completes," T. I, p. 457), who was my first " atomic weight teacher " in 1875 (but who would read such 'antiquated' papers to-day ?). He describes the distillation of 50 gm. of his purest silver in the flame of the oxyhydrogen blowpipe and says: " Je dois avouer toute fois que, dans les operations que je viens de d6crire, la moiti6 au moinas de I'argent employe a Ut6 perdue. En effet, il a 6t6 entrain4 a 1'6tat de vapeur bleue pale avec le courant de gaz tonnant, quoiqu'il fit cependant moder6, et sans excbs trop grand d'oxygene; il a 6te repandu dans l'air ambiant dont il a trouble la transparence, et auquel il a communique une saveur m6tallique tres sensible." From this important observation it follows that when silver once passes into the state of vapour it is not easily condensed in a solid state, but forms only a colloidal dispersion as a fog. Large quantities of silver heated in tubes give a condensation of the metal, but when a small quantity was heated and fused, the silver vapour-the weight of which was, in the said experiments, of the order of 0 0001 gm. and which would occupy in the solid state 0 00001 cm.3-may have passed out of the apparatus.Messrs. Baker and Riley say that they controlled the weight of the fused silver obtained by repeatedly melting and weighing it to constant weight. But the question arises: What was the weight of the silver obtained in a fine state of division immediately after decomposition of its oxide by heat and before fusion ? Such silver has a very great surface, and during fusion a small loss by evaporation may have taken place. After fusion, its surface has become very small and, last but not least, it was " coated with a very thin film of dross consisting of silica." To these circumstances the fact is very probably due that no appreciable loss of weight of the silver was observed after repeated fusio

ISSN:0028-0836    

DOI:10.1038/119526c0

出版商:Nature Publishing Group    

年代:1927

数据来源: Nature

摘要:

THE convection of heat to or from the walls of a circular tube conveying fluid in turbulent motion has been studied by a long line of investigators, among whom may be mentioned Joule, Reynolds, Stanton, Nüsselt, Soennecken, Jordan, Stender, Heinrich, and Stückle. From dimensional considerations Rayleigh (NATURE, Mar. 18, 1915, p. 66) deduced a formula which, written in non-dimensional form, is equivalent to.where a = coefficient of transmission of heat. d = diameter of tube.V = mean velocity of flow. Ic = conductivity of fluid.= viscosity of fluid. v = kinematic viscosity of fluid = ,4p.h = diffusivity of fluid = k/sp. s = specific heat of fluid. -p = density of fluid. For gases Stanton (Tech. Report Adv. Committee for Aeronautics, 1912-13) gave a formula reducible to ad (vd) '" const. i k . (2) in which n = 0 75 approximately for smooth tubes.Niisselt (Z. V. d. I., 1909) proposed a formula for gases reducible to his later form: ad lVd\" a =const. Vd) ' k C .. (3) which is equivalent to (2) (n = 078). Formulae for water of the form: a proportional to Vn, . (4) have been proposed by Stanton (Phil. Trans. Roy. Soc., 1897), Soennecken (Forsch. Heft 108/109), Stender (" Wtrmeubergang an strdmendes Wasser," Springer, 1924), and others. These formulae do not make explicit mention of the conductivity. Stender finds that the index 'an' depends on an equivalent mean temperature r0 C. = 09Tm + 0-lTw, where Tm = mean water temperature and Tw wall temperature.Experiments with oil have been carried out by Heinrich and Stickle, but not fully analysed (Forsch. Arb. Heft 271). The object of the present note is to suggest a general formula applicable to all fluids, liquid or gaseous, under conditions of turbulent flow in circular tubes, namely: ad 0 0260(YA\ fQ%) k V * (5) in which f(k/ys) is given approximately by the following values: h/v=l/cls 0 01 0 10 0 40 1-30 f(h/t) =f(k/ls) 0-97 0 895 0-835 0-785 which lie well on a smooth graph.This formula agrees well with the experiments of Heinrich and Stfickle for oil, those of Stanton, Soennecken and Stender for water (r= 100 C. to 7=700 C.). It also agrees as well with the results of Jordan, Niisselt, Pannel, and others for air, as these agree amongst themselves. A crucial test of the value of formula (5) would be given by experiments with mercury for which the value of k/us lies outside the range of the experiments referred to above.A complete formula should take account of the ratio of length to diameter of tube, or else the ratio of initial to final excess temperatures, but (5) is put forward as a step towards the correlation of the results of diverse experiments in which the ratio of length to diameter of tube exceeds about 2

ISSN:0028-0836    

DOI:10.1038/119527a0

出版商:Nature Publishing Group    

年代:1927

数据来源: Nature