摘要:

DISCUSSIONS centring round the application of scientific knowledge to the solution of social problems result too often in generalisations which have no regard to the very different positions in which the physical, biological, and social sciences find themselves to-day. It is a commonplace to say that if science is to be of use, research must be entirely unhampered. Generally speaking, there is nowadays freedom of research in all branches of science, though it can scarcely be supposed that, in countries such as Russia, social scientists are wholly free to investigate the institution of private property and the system of private enterprise. The situation of the physical, biological, and social sciences is thus much the same so far as pure research is concerned. When, however, we come to consider the application of scientific knowledge, the situation is very different in each case. Where research continues unhampered there arise from time to time opportunities of employing the results of research, and our attitude towards these possibilities may be either scientific or unscientific. By a scientific attitude is meant the realisation that what research has disclosed is merely a method of producing with a greater or less degree of certainty a particular result. Methods themselves are neither good nor bad. Questions of value do not arise at this point, but only when we go on to consider the effect of the employment of these methods upon those persons who use or are in any way touched by the methods. Methods of mass production either do or do not result in greater productivity. This is a problem preliminary to and wholly separate from the question of the moral effect of mass production upon the workers.So far as the physical sciences are concerned, we are no longer in the mood to regard aeroplanes as 'unnatural' or flying as 'impious.' Here the scientific attitude is in fact general. The social sciences stand at the opposite pole and there is as yet little sign of the emergence of the scientific attitude. Divorce, nationalisation, and capitalism are held to be good or bad in themselves; they may be worshipped or regarded as the evil one barely if at all disguised. The biological sciences occupy a midway position. Prof. Julian Huxley,' in his lecture on " Biology and Human Life " delivered before the British Science Guild on IBiology and Human Life. Norman Lockyer Lecture, 1926, by Prof. J. S. Huxley. (London: British Science Guild, 1926.) Is. Nov. 22 last, discusses the use of the results of biological research in relation to health, quantity, and quality of population. The consideration of health raises the question of the use of vaccines, of the quantity of population that of contraceptive methods, of the quality of population that of controlled breeding. No one at all well acquainted with popular discussions of these matters could claim that the scientific attitude is predominant. It is probably growing. It does not, however, seem to be more prominent in certain of the groups, social, religious, or political, into which the population is divided than in others. People regarded by others or regarding themselves as possessing ' advanced ' views do not seem to be remarkable for their scientific outlook as defined here. A recognised leader of advanced political thought recently described inoculation as ' unclean.' This is equivalent to thinking that the taking of a census is a wicked act displeasing to Providence, and likely to be visited by an 'epidemical distemper,' as widely held in the eighteenth century. There are passages in Mr. H. G. Wells's " World of William Clissold " which suggest that he regarded birth control as an excellent thing in itself-precisely the same error the other way round.Just as it cannot be said that people of certain religious views or of particular political opinions are more scientific than others in their attitude to the possible use of the results of research, so it does not appear that men of science as a whole are especially remarkable for their power of distinguishing between the efficiency of methods and the reactions upon moral conduct of the employment of the same methods. They are apt to think that because a method is effective it is therefore good. This statement cannot, however, be made of Prof. Huxley. He does advocate, it is true, the use of contraceptive methods and the control of breeding, but he sees that he must justify his advocacy not merely by observing that problems of the quantity and quality of population present themselves which these methods might solve, but also by a demonstration, so far as it can be given, that the moral effects would be good. It does not seem, in fact, to be difficult to build up a case to show that few scientific methods have ever offered so much opportunity for the unselfish regard for the welfare of others as those which permit us to regulate numbers-which is a necessary precedent to a life of decency in any community-and to go some way at least towards ensuring that the next generation shall begin life reasonably well endowed with all that makes possible a full and useful existence.It is thus of primary importance that if, as Prof. Huxley desires, use is to be made of our rapidly increasing biological knowledge, what has here been described as the scientific attitude towards the application of the results of research should become more widespread. It cannot be too strongly urged that those who press upon the public the use of contraceptive methods as admirable in themselves are just as reactionary as their opponents. If we now leave this point and pass on to consider the knowledge available for dealing with the problems of quantity and quality of population, it is evident that we are better informed regarding methods of controlling quantity than of controlling quality. It is true that much remains to be done in the way of investigating the precise efficacy and incidental results of methods of controlling quantity. But the problem is of far less magnitude than that of quality. Progress can be made by independent research workers, which is by no means the case in some of the most important aspects of the quality problem.If we are to have adequate methods of dealing with the quality problem, research must be prosecuted in four distinct fields. There is first the problem of the mechanism of heredity, and secondly that of the mode of inheritance of human character. These are problems which the independent investigator can attack. It is unnecessary to refer here to the amazing developments in our knowledge of the mechanism of heredity, which appears to be essentially of the same nature in all organisms. Progress in the second field is of necessity slow because of the impossibility of experiment. The research worker must make the best of such data as are available resulting from the uncontrolled matings of the human species. There is next the third field concerned with the distribution of inherited characters within the population, and the fourth concerned with the change in that distribution. We must know where certain qualities are to be found or, to put it in another way, how far social classes, occupational and economic groups, differ from one another now in respect to these inherited characters, and whether these differences are becoming greater or less. Within these third and fourth fields the independent research worker is nearly powerless so far as the collection of data is concerned. A very little reflection will show that the efforts of independent research workers can never alone be expected satisfactorily to elucidate the position. It would be as reasonable to expect the unaided efforts of research workers in economics to obtain a satisfactory review of the trade or income of the country without recourse to government figures of imports, exports, and income tax, as to expect biologists by their own unaided efforts to give us at all full information as to the genetic composition of the population. It follows that adequate guidance cannot be given, even if the will to use it is there, unless government machinery can be set in motion to collect the data. If we have to wait for a government of this degree of enlightenment, a bleak prospect opens out. But encouragement may be obtained if we refer again to the economists. Income statistics are not collected because an enlightened government wishes to keep a watch upon the national income, but because a hard-pressed government has to find money. Economists have to use these data, inadequate as they are, for their own purposes. There is similarly a possibility of the use by biologists of government data regarding the medical inspection of school children and of official data from the census, for the purpose of elucidating in some detail our biological heritage and the changes which are taking place. The difficulties at present are great, but government machinery exists which, if slightly adapted for this other purpose, would allow an examination to be made of the position and a watch to be kept of changes at least from decade to decade. The most urgent needs are that the medical examination of school children should be standardised in order that the data could be aggregated and the results of one year compared with those of another, and that the questions asked in the census of 1911, which rendered an inquiry into differential fertility possible, be made a permanent feature of the census. At the present time, we can do little more than guess what the position is.The community must be brought to learn that there is no more fruitful use of communal resources than when applied to keeping a watch upon the biological inheritance of the community. It may or may not be desirable for us to copy Sweden, where a State Institute for Race-Biology has been founded for this purpose. But until ways of accumulating the necessary knowledge are found, we shall not be in a position to take effective steps, as Prof. Huxley desires, to "weed the garden of humanity."

ISSN:0028-0836    

DOI:10.1038/119449a0

出版商:Nature Publishing Group    

年代:1927

数据来源: Nature

摘要:

THE cause of research in historical chemistry T owes much to the work and influence of two men: Marcelin Berthelot in France, and Edmund 0. von Lippmann in Germany. It is an interesting coincidence that the approaching celebration, in October next, of the centenary of Berthelot's birth should follow so closely upon a public recognition of von Lippmann's activities in the common field of these two eminent chemists and chemical historians. At the recent jubilee of the Deutsche Gesellschaft fuir Geschichte der Medizin und der Naturwissenschaften, von Lippmann was awarded the Sudhoff medal for his researches in historical chemistry; the volume under review has now been issued under the auspices of the same society to mark the seventieth birthday of one whom Ruska acclaims in an eloquent dedication as " Meister und Fuhrer " in this field. It is to be remarked with regret that the volume contains neither a biographical notice of the doyen of chemical historians nor a discussion of his work and its influence on the progress of historical chemistry. Von Lippmann's industry and versatility may be gauged, however, from the accompanying list of 18 books and 159 original papers, etc., published by him since 1878. Among the more familiar book titles are " Geschichte des Zuckers," " Die Chemie der Zuckerarten," " Entstehung und Ausbreitung der Alchemie," and " Zeittafeln zur Geschichte der organischen Chemie "; while the papers contain historical references to such diverse subjects as sugar, the thermometer, aluminium, gunpowder, alchemical poetry, the Ebers papyrus, distillation, alcohol, Petrarch on alchemy, the use of petroleum in the Middle Ages, the name ' Berzelius,' chemistry and technology in Herodotus and in Dante, and so forth.Apart from the items which have been mentioned, the book consists of a series of twenty-two essays by acknowledged authorities on subjects of special interest in historical chemistry. The contributions, which are arranged chronologically, touch upon the development of chemistry from the Babylonian era, through the Greek and Islamic periods, down to the present day. The collection conveys a striking impression of the vigorous growth of research in historical chemistry during recent years, particularly in Germany. Some of the papers attain a high level of scholarship, but it is not possible here to do more than comment upon a few points of outstanding importance or interest. Darmstaedter (Munich), in a paper on the lapis lazuli, indicates that the great mythological significance of this stone in the Babylonian-Assyrian civilisation led to the production, by a carefully guarded process, of an artificial stone containing small quantities of copper and cobalt. Hopkins (Amherst, Mass.) endeavours to base a comprehensive explanation of early alchemical work upon a philosophy of colour, the trend of his argument being illustrated by such quotations as the following: " Cast a sulphur preparation upon silver to get gold" (pseudo-Democritus); " It is the tinctorial principle which causes the vapour to develop the gold " (Zosimus); " Mare tingerem si mercurius esset" (pseudo-Lully). It may be objected that colour was only one of many qualities, regarded in the Aristotelian sense as accidental, and that even the early alchemists knew gold when they encountered it. The sweeping claim that all alchemical practice was based upon an unvarying sequence of colours also invites criticism.The most important contributions to this work are those dealing with Islamic chemistry. Wiedemann (Erlangen) directs attention to what is perhaps the first mention of magnetic polarity. Ibn 'Abd al-Rahim, quoted by Al-Jildaki, refers to a foursided stone which was capable of attracting or repelling a certain piece of (magnetised) iron when presented to it in different ways. It may be noted that Petrus Peregrinus, of Picardy, made a similar observation in the thirteenth century. The volume contains two contributions to the JAbir (Geber) problem which are undoubtedly of first-class importance. It may be recalled that about two years ago Darmstaedter discovered a Latin version of Jabir's " Book of Mercy "; Ruska (Heidelberg) now records the recent discovery in Egypt by Meyerhof of a large portion of the Arabic text of Jhbir's Liber LXX., and gives a preliminary survey of the contents of this " unvergleichlich kostbaren Fund." For the second time within two years Latin and Arabic texts of JAbir have been brought together, and such remarkable successes should encourage the enthusiastic band of investigators in this field to prosecute with redoubled ardour their search for the Arabic originals of the Summa perfectionis and other works of the central figure of Muslim chemistry." What Aristotle was for philosophers, Jhbir was for chemists," writes Holmyard (Bristol) in the sole British contribution to the volume under notice, " and a full investigation of his life and writings would unquestionably be of the utmost value for the history of chemistry." Holmyard now adduces important new evidence from Al-Dinawari's Kithbu'l-Akhbar al-Tiwhl (Book of Lengthy Narratives), which, although handled with commendable restraint, will probably be accepted generally as providing a satisfactory settlement of the difficult questions of JAbir's birth, parentage, nationality, and date. The evidence indicates that JAbir was the son of a certain Arab Shi'ite known as ' Hayyhn the druggist,' and that he was born at Tfis about A.D. 721-722, during his father's presence in Khurasan on a political mission for the 'Abbhsids. A further elucidation of J&bir's relations with the Barmakides and with Ja'far al-Shdiq provides an apparently effective refutation of Ruska's contention that the Jhbir-Ja'far connexion was a myth. Students of this period will welcome the promised publication, by Geuthner of Paris, of a complete edition of Jhbir's Arabic works, accompanied by English translations. Other articles deal with subjects of such general interest as chemical symbols (Walden, Rostock), Priestley's defence of the doctrine of phlogiston after his removal to America (Davis, Cambridge, Mass.), chemical instruction in the German universities in the first quarter of the nineteenth century (Lockemann, Berlin), and the GoetheWackenroder correspondence (Brauer, Cassel). The series concludes with an entertaining chemical potpourri by Speter (Wehlen). Those readers who are conversant with the efforts of William Barnes, the Dorset poet, to redistil the waters from 'the well of English undefiled,' will take particular interest in the suggestions for 'purified' German chemical terms; but though the puristic inorganic chemist might conceivably prefer " Sauerstoff " to " oxygen," his faith would need to be greater than a grain of mustard seed if it permitted him to accept for himself the designation "Nicht-Kohlenstoffverbindungsscheidekuinstler "The book is well printed, and it contains an excellent frontispiece portrait of von Lippmann. It will be found both interesting and useful by all chemists who have developed that lamentably rare sense of historical continuity with the past which is so desirable in the teaching and study of science.

ISSN:0028-0836    

DOI:10.1038/119451a0

出版商:Nature Publishing Group    

年代:1927

数据来源: Nature

摘要:

DESPITE any criticism of detail, this is a 11) work indispensable to all persons for whom books are practical tools. This volume will have a special appeal to readers of NATurE; although it includes the classes of science, art, music, drama, domestic arts, and sports, three-quarters of the volume (which contains pp. 1681-2510 of the complete work) come under the heading of science. Actually, however, this heading is used somewhat unscientifically, because it includes all industries and trades as well as the pure sciences. Also at first sight one is somewhat surprised to find here such headings as immortality, Christian science, industrial and economic history. The explanation is largely that the producers of the work have boldly faced the difficulty that the earlier volumes are tending to be out-of-date before the last volumes are completed.As a corrective, wherever possible they have included 'additions' to the bibliographies of the subjects of the earlier volumes, and these 'additions' have been tacked on to more or less cognate subjects in the present volume, convenience being the controlling factor rather than a strict adherence to a scientific arrangement of topics. This method has not been wholly disadvantageous. Besides affording probably the best means of bringing the earlier volumes up-to-date, it now gives us psychology in all its aspects as a branch of science. At its original place under philosophy its housing was somewhat old-fashioned; for psychology now passes from the speculative domains of philosophy into documented and precise methods of handling such as allow it to be regarded as a science proper.We have tested the volume in some dozens of instances, and only exceptionally has it failed to produce the entry expected. One instance was " Population," by H. C. Wright, which was worth inclusion as a simple, clear, and inexpensive statement of the mildly-pessimistic attitude of the Cambridge school on the population question; another was " A Hillside View of Industrial History: a Study of Industrial Evolution in the Pennine Highlands," by A. Newell. This book, on account of its original investigations, was well worth inclusion in the 'additions' to industrial and economic history now given in this volume under arts and trades to supplement the treatment of the subject under earlier headings. The latter case, however, is not quite a fair test, because the book was published somewhat obscurely in Todmorden; although, in fact, it received favourable critiques through the usual channels. That a compilation should fail only in such points as this over a large number of tests, especially when allowance is made for differences of opinion as to what the ' best books ' really are, shows the thoroughness with which the ground has been covered. After all, however, the 'best book' is only best in relation to the purpose for which it is either intended or used. We are only half on our way towards selection when we get a list of 'best books' on a given topic, if that list includes all the best books without some attempt, if not at evaluation, at least at a comment on the point of view presented. Wright's book mentioned above is a good illustration. Some little evaluation is attempted in " The Best Books " by the use of an asterisk to indicate any work of outstanding importance. This mark of pre-eminence is, quite rightly, very sparingly used, and it is supplemented in a very small minority of examples by some brief evaluatory or explanatory comment. One would like to see the latter idea carried much further, but it would be.a gigantic additional task to impose on the shoulders of the present compilers; this latest volume would probably have followed its predecessor at an interval of thirteen years instead of three years. In additional excuse, this work was a War casualty. The new edition was begun in 1910, the second volume appeared in 1912, the third in 1923, and now the fourth is published in 1926. But this latest volume shows a vitality unaffected by the passage of years, or by the happenings often inevitably associated with the production of a work over so long a period; for the ranks of its compilers have not been unaffected by the limitations of human mortality.Such small additional points of criticism as occur would deal with the age of many books here noted and the consequent difficulty of obtaining them by purchase. Particularly is this the case in architecture, from which list one misses Aldin's " Old Manor Houses," but it is true that these books are nevertheless standard books. This is a great work, unsurpassed in its scope or accuracy by any similar work in any other country. It now appeals almost pathetically for its index volume to make it fully usable, although there is an excellent system of cross-references between correlative topics. But could not some more straightforward notation be used than one which refers the inquirer to H § 47 *******

ISSN:0028-0836    

DOI:10.1038/119453a0

出版商:Nature Publishing Group    

年代:1927

数据来源: Nature

摘要:

THuE explanatory title of this book, namely, "A Study in the Natural Philosophy of Newton's Time," gives a good indication of the scope and nature of the contents. It is certainly desirable in these days, when science, philosophy, and religion are all recognised as important contributors to the progress of human thought, to have such an outstanding period as that of the seventeenth century and early eighteenth surveyed, especially with reference to the atomic revival which, as the author points out, is very closely associated with the name of Pierre Gassendi. The work of Robert Boyle, and also the dispute between Gassendi's and Descartes' schools of atomism, are traced in the first chapter, and the question as to the divisibility of matter is shown to have formed an important phase of the intellectual background of Newton's time. Galileo's ideas with regard to movement are also traced, and so the way is prepared for the Newtonian atomism which is discussed in the second chapter. The objections to Descartes are dealt with at length, and it is shown how that, to Newton, the idea of God was essential. The influence on Galileo is brought out in this chapter with regard to the theory of force.In the third chapter, Newton's doctrine of gravity is treated, and throughout what follows, careful attention is paid to the question of action at a distance and ether. The controversy with Liebniz and the alleged ' occult powers' reveal the keen discussion in matters of natural philosophy which took place in the period under discussion. The 'active principles' of Newton receive careful treatment in this chapter, which closes with the mathematical theory of gravity. The fourth chapter naturally deals with the metaphysical doctrine which Newton's theory suggests; attention is directed to the mystic influence of Jacob Boehme.The last chapter discusses the relation of mathematics and physics to philosophy in general, and deals with the opposition which Newton's use of hypothesis met with in the polemic directed against him by the Cartesians.

ISSN:0028-0836    

DOI:10.1038/119454b0

出版商:Nature Publishing Group    

年代:1927

数据来源: Nature

摘要:

A NOTICE of the first three volumes of this series appeared in NATURE, vol. 118, p. 44 (July 10, 1926); the fourth volume, now before us, deals with travel in Egypt, Angola, Australia, Antarctica, Venezuela, and Haiti. Doubtless the various articles are being published in the order in which they come to hand, but the result, in the case of the present volume, has been too miscellaneous a grouping. In any further edition of the whole work it would obviously be an improvement to redistribute the articles among the several volumes, in order to bring together those having some bearing on one another. Like its predecessors, this volume is packed with useful and very much up-to-date information, although the sections on Venezuela and Haiti are short and scarcely enter into sufficient detail. In the section on Australia several pages are devoted to hints for botanical collecting, but most of the articles, being written by geologists, will probably be of especial help to members of geological expeditions. Prof. Griffith Taylor gives an interesting account of the experience gained by Capt. Scott's last antarctic expedition; his remarks should be very helpful when the preliminary arrangements are being made for any further expeditions to that part of the world. The illustrations in this book are well reproduced, and give a good idea of travelling conditions in the various regions.

ISSN:0028-0836    

DOI:10.1038/119455c0

出版商:Nature Publishing Group    

年代:1927

数据来源: Nature

摘要:

“Who is this that darkeneth counsel by words without knowledge?” (Job xxxviii. 2).Prof. J. S. Huxley (NATURE, Mar. 5, p. 350) writes: "Prof. Walker says . . . that Dobell 'proved' that hereditary characters could not be controlled by chromosomes in certain Protozoa." What I did say is quite different. Here it is: " There is a number of organisms in which the distribution of the chromosomes is such that they could not possibly convey a Mendelian character." I did not use the word ' proved,' which Prof. Huxley places in inverted commas, from beginning to end of my letter. He goes on to say, " The main reason advanced by Dobell concerned sex," and " if Prof. Walker had been better acquainted with genetical literature he would have remembered that almost simultaneously with Dobell's 'proof,' Wettstein was demonstrating experimentally, and conclusively, . . ."Mr. Clifford Dobell in the paper referred to, having given a detailed description of the distribution of the chromosomes in certain organisms, begins his argument as follows: "Let us now select a particular character and a particular chromosome, and consider their relations to one another. It is really immaterial which character or which chromosome we take; but for the sake of argument let us take sex as the character to be studied." Any one reading the paper will find that it was written with the object of confronting with actual facts certain sweeping generalisations of which Prof. Huxley so constantly provides us with examples. He will also see that sex has nothing to do with the argument. So far as I can see, Wettstein's work on mosses, which Prof. Huxley quotes but to which he gives no reference, has no direct bearing on the particular point at issue, and I must place his use of it in the same category as his misquotation of me and his misunderstanding of Mr. Dobell.Referring to Prof. Johnstone and myself, Prof. Huxley says, " But has Liverpool never heard of Boveri's experiments on disperm sea-urchin eggs, published exactly twenty years ago ? " This work was published too late for me to refer to it in my little book on cytology (1907), but Prof. Huxley will find sufficient evidence to show that I had read it in my " Hereditary Characters " (1910, Edward Arnold, London, pp. 37-8 and 222). I would bring a remarkably apposite passage from another work to his notice." Now, from the purely artistic point of view, . . I consider it an axiom that one should never appear to doubt that the other side has performed the elementary duty of acquiring proper elementary information, unless there is demonstrative evidence to the contrary " (Thomas H. Huxley, " Collected Essays," vol. 6, p. 373. Macmillan, London, 1909). As, however, the main object of all of us is the ascertainment of truth, I must ask to be forgiven for wasting so much space on trivial self-justification and return to my protest against the constant presentation of doubtful theories as proven facts. I have watched the development of 'neo-Mendelism' from its inception. (Having regard to Prof. Huxley's methods of controversy I must be precise. I do not mean from the time of the first publication by Mendel in 1865, but from the time of the 'rediscovery' very many years later.) I have watched, often with amazement, sometimes with amusement, assumption piled upon assumption as occasion arose to make the ' neo-Mendelian " laws' agree with the results of breeding experiments. The attitude of Prof. Huxley and others of the same school seems to me to approximate to that of the advertiser who is convinced that the more often he repeats a statement the greater will be the number of people who will believe it. Out of the vast accumulation of assumptions has arisen the jargon in which Prof. Huxley sets forth what he claims to be a statement of the fundamentals of genetics. This statement of fundamentals represents, not proven facts, but assumptions for which a varying amount of evidence is available. May I be allowed one final quotation: The meaning doesn't matter if it's only idle chatter of a transcendental kind, And every one will say As you walk your mystic way, "If this young man expresses himself in words too deep for me, Why, what a very singularly deep young man this deep young man must be ! " (W. S. Gilbert, " Patience," Op6ra Comique, 18

ISSN:0028-0836    

DOI:10.1038/119456a0

出版商:Nature Publishing Group    

年代:1927

数据来源: Nature

摘要:

I SHARE Prof. Johnstone's inability to solve either crossword puzzles or Mendelian results (NATURE, Feb. 26, p. 319). But I do not think this should encourage him to decry the carrying out of breeding experiments by men who can properly interpret them. It seems reasonable to regard Drosophila as the sum of a number of factors arranged in a certain way, just as a crystal of alum is an aggregate of molecules orientated in a definite pattern, of atoms specifically arranged to give molecules, and of electrons to give atoms.It is almost an axiom of scientific method that analysis must precede synthesis. The first stage toward the solution of the Drosophila problem, then, must of necessity be one of analysis; the splitting up of the entity Drosophila into genes and factors. This analysis is far from being complete yet. With the materials gained thereby we can proceed to the synthesis, namely: Why is this aggregate Drosophila, and not Pulex or Homo ? An attempt to synthesise before the materials are available is as ineffectual as the attempt to make bricks without straw. The problem Prof. Johnstone propounds is, however, the really fundamental one; and until we reach the stage of synthesis, Drosophila will not be allowed to retire into the oblivion it so well deserves.

ISSN:0028-0836    

DOI:10.1038/119457a0

出版商:Nature Publishing Group    

年代:1927

数据来源: Nature

摘要:

I HAVE every sympathy with Prof. Sollas and with all geologists whose scientific studies have been impudently challenged by ignorant charlatans. But I have met one honest and modest dowser who never exercised his powers for payment and had no theory as to the nature of the faculty which he believed he possessed. From the cases described by Sir William Barrett, it appears that there are other dowsers who are honest, and it really seems to me that the cause of the dowser's sensations which may lead to the discovery of water is as worthy of study as, say, the polarisation of light that may be used for the microscopic determination of mineral. Theinvestigation may, I think, be better undertaken in either case by specialists who are not concerned with the applications. If there is anything in water-divining, I am sure that it is not occult in the sense of “involving the supernatural, mystical, magical,” and if it be occult in the sense of being “beyond the range of ordinary knowledge” (both definitions are given in the Concise Oxford Dictionary) I only urge that efforts should be made to extend that range as it has been extended in recent years to clear up other obscure ph

ISSN:0028-0836    

DOI:10.1038/119458c0

出版商:Nature Publishing Group    

年代:1927

数据来源: Nature

摘要:

A CURIOUS and somewhat unexpected property of the pressure of a gaseous mixture has come to my notice from an examination of some recent experimental work. Holborn and Otto (Zeit. f. Phys. 23,77, 1924; and33, 1, 1925) have determined the isotherms of a mixture of helium and neon, and of helium and neon alone, and have shown that the isotherms can in each case be represented with great accuracy by a formula of the type, whenAandBare given suitable values. SinceBis small (of the order 10−3), this equation can also be, wherevin each case is the ratio of the volume to the volume under standard conditions, and is therefore inversely proportional to the molecular concentration. It follows thatBis a measure of the deviation from the perfect gas law. The curious fact emerges that for the same temperature the value ofBfor a binary mixture may be greater than that of either of the constituent gases. In other words, the pressure of a gaseous mixture may be greater than that of either of its constituents, even when the molecular concentration and temperature are in all cases the same.I hear, too, from Prof. Masson that Dr. Gibby and he have also discovered the same phenomenon independently in some experiments with mixtures of hydrogen and helium. They are at present extending their work in order to examine this question more closely. The explanation is to be sought in terms of intermolecular forces. Cohesive forces between molecules tend to lower the pressure, while repulsive forces tend to increase it, and the relation of the one effect to the other depends on the temperature. A mathematical investigation for the particular case when both fields can be represented by inverse power laws (Proc. Roy. Soc., A, 112, 214; 1926) shows that at low temperatures the cohesive forces outbalance the repulsive and the deviation from the perfect gas law (B) is negative. With increasing temperature the effect of the repulsive fields becomes increasingly important until ultimately B becomes positive. Finally, a temperature is reached for which this positive deviation is a maximum, and then the correction falls asymptotically to zero.This maximum property of the deviation, indicated by theory, is borne out by experiment (Hlolborn and Otto, Zeit. f. Phys., 23, 86; 1924). The temperature at which the deviation is a maximum is 1400 C. in the case of helium, 150' C. in the case of hydrogen, 2600 C. in the case of neon, etc. In this maximum property lies the explanation of the increased pressure of the gaseous mixture. The temperature of maximum deviation of a mixture lies between those of its two constituents, and near this temperature the deviation of the mixture from the perfect gas law is greater than that of either of its constituents. For a certain range of temperature the pressure of a gaseous mixture may therefore be greater than that of the same concentration of either gas alone.Furthermore, theory provides an expression for the relative proportions of the gases of a mixture for which the pressure is a maximum at a given temperature. The already-mentioned work of Dr. Gibby and Prof. Masson will, it is hoped, prove to have provided experimental evidence to test this resul

ISSN:0028-0836    

DOI:10.1038/119459a0

出版商:Nature Publishing Group    

年代:1927

数据来源: Nature

摘要:

THE Research item headed “Antarctic Echinoidea” (NATURE, Feb. 19, p. 294) says: “Antipneustes is a name that replaces Amphipneustes Koehler 1901 to avoid confusion with the unknown Amphipneustea Wiegmann.“ Since the name Amphipneustea was as unknown to me as to the writer of that note, I have taken some trouble, with the help of Mr. C. D. Sherborn, to get to the bottom of the puzzle. First of all, it appears that the name Antipneustes was proposed, at Prof. Koehler's request, on p. 427 of Lambert and Thiéry, “Essai de nomenclature raisonnée des Échinides,” published in 1924, but only just obtained for the Natural History Museum. The supposedly conflicting name Amphipneustea is, on p. 428 of that work, credited to Wiegmann, 1837, without further reference. The “Nomenclator” of Agassiz helps one to track this down to A. F. A. Wiegmann and Ruthe, 1832, “Handbuch der Zoologie,” p. 527. The name, however, is applied to a family of Pulmonate Mollusca, and therefore could not conflict with Amphipneustes Koehler, even if the spelling were the same. It may be mentioned that, in 1820, B. Merrem, “Tent. Syst. Amph.,” gave the name Amphipneusta to a family of Reptilia.The upshot of this is that Amphipneustes Koehler 1901 stands, and that Antipneustes is an unwanted synonym; and the moral is:

ISSN:0028-0836    

DOI:10.1038/119460c0

出版商:Nature Publishing Group    

年代:1927

数据来源: Nature