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| 1. |
Science for Citizenship |
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Nature,
Volume 120,
Issue 3015,
1927,
Page 213-215
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摘要:
FACILE criticism will always find vulnerable J- points of attack in any educational system. Only a short time ago, much was heard in the popular press of lie yjfcp*^! prominent business men on thp tefidyHMroT of their ojdce \>oys. Our wa*f tK^ef^rtr/coEfclemned in Mo; our ovaw expenditure on education was adjudged complete wStste. While such hasty judgments, based only on partial observation and imperfect evidence, may be set aside as carrying little weight, those who come most closely into contact ' with the products of the elementary school may still feel that all is not entirely well with education in England to-day. It may be granted that as compared with twenty-five years ago, when the Education Act of 1902 came into force, vast strides have been made. A higher standard is attained, a greater degree of accuracy and a stronger grip of the facts is to be observed, together with less tendency to a parrot - like repetition of the form in which the subject matter has been received. On the other hand, knowledge and inference which depend on that elusive quality, the intellectual flexibility and adaptability which for lack of a better term examiners connote by 'general intelligence,' seem rarely to show an advance commensurate with the improvement in specific branches of learning.
It may perhaps seem at first sight unfair that any educational system should be judged by the product of its lower grades-a product, too, of which the raw material is drawn in a large number of cases from sources which in all their conditions -intellectual, social, and moral-are unfavourable and sometimes entirely inimical to the aims and influence of the school. But it must be remembered that, since the beginning of the present century, what is almost a social revolution-still, however, incomplete-has taken place in the personnel of the elementary school staff. No longer do they proceed by the treadmill of elementary school, pupil-teacher centre, elementary training college, and back to the elementary school. The throwing open of the secondary school to the elementary school class, and the extension of university studies in the training colleges, have brought back to the work of teaching in the schools of elementary grade, men and women whose intellectual and social outlook have been broadened by intimate contact with other minds of varied culture, interests, and social antecedents, which in former conditions, as a general rule, they might never have encountered while in the formative stage of their career.IT is not necessarily a mark of carping criticism to hold-indeed it would he idle to deny-that the qualifications of the elementary branch of the profession are still open to improvement in certain directions; hut a great step forward has been taken towards the ideal of those who long ago hoped that the majority of teachers in the elementary school would one day hold a degree, not as a cachet in an already honoured profession, hut as the outward sign of certain qualities and cultural attainment. What they looked toward in their staff of the future was not a band of specialists, each highly trained in his own subject, but of men and women of wide culture who might introduce into the elementary school a wider outlook and cultivate in the material on which they had to work an intelligence trained to alertness in appreciating the varied aspects of life and knowledge as a function of existence as members of an economic, social, and political community. To this end the secondary school and university courses then seemed the obvious avenue of approach.
It must, however, be admitted that the trend of events has by no means justified expectation. It is not intended here to enter into a detailed criticism of the system of training teachers, but merely to use certain features in that system as illustrating some present tendencies in education as a whole. Those of the older school saw as their ideal a training college in which ultimately a majority if not all of the students would be working towards a degree, in which arts and science would be fairly well balanced, in which different interests, different studies might meet as in a common pool to their mutual intellectual advantage and understanding. The narrowness of the training college, its seminary atmosphere, would thus be alleviated. Circumstances, however, have decreed otherwise, and instead of the numbers being fairly well balanced, science has as a general rule become preponderant. While the Board of Education has continued to examine the greater proportion of the students this has been of less moment. Those who were responsible for the general lines of the examination were well acquainted with conditions in the schools. Inspection by the Board of both colleges and schools secured that training should be carried on with a view to the need of schools for certain qualities and capacities in their teachers. When in the near future the Board will no longer be responsible for the examination of students in training colleges, however logical its decision may be, and even though it may continue to inspect and take part in the examination of the technical side of training, the divorce between the examining body and the elementary schools will be complete, while, having in view the character of university courses as they are regulated at present, it may aggravate a tendency towards specialisation which is part a symptom, part a cause of the defects of our educational system as a whole.For many years the training college stood to the elementary school in a relation analogous to that of the university and the public school. For long it was for the brilliant boy or girl in the elementary school practically the only avenue of intellectual advancement. Theoretically, it is true, it led to one profession only, but in practice some made it only a means to an end, taking advantage of the general rather than the professional education, and after a few years left the profession to attain eminence in other walks in life. The academic side of the training college, from being subservient to the technical as it was when training was first instituted, became more and more important, and with the introduction and extension of university work it has tended, and tends increasingly, to overshadow the function of a training college as an institution of which the aim was not primarily academic. It must in fairness be recognised that this has been forced on the training colleges by the educational antecedents of the students, arid no one would deprecate that the academic education of the intending teacher should be carried to the utmost limit that his capacity and opportunity allow. But it is a fact that the student who passes from the elementary school through the secondary school to the training college, if he takes up university work, tends to elect for a science degree. It is more than a moot point whether a course leading to a science degree, as at present laid down along highly specialised lines, constitutes the most suitable preparation for the career of an elementary school teacher.
It may perhaps appear that in considering the case of the teacher too great stress has been laid upon what is relatively a small proportion of those who come under a part only of the whole system. But the teacher is a crucial example; in his case the effect is cumulative, and with present changes the tendency of which he is characteristic is increasing. Turn to the secondary school, and the same trend towards highly specialised courses in science is perceptible. In the Report of the Board of Education for 1926, in dealing with the examination of grant-aided secondary schools, it is stated that while Latin holds its own and Greek shows a decrease, thenumber of candidates taking chemistry and physics is increasing. Of the number of candidates taking the First Examination in 1926, 40-2 per cent, offered chemistry and 24-7 per cent, physics. In elementary and experimental science the figure was 5-7 only, and in general science 2-5. In the same way, of the 437 advanced courses recognised in 309 schools, 210 were in science and mathematics, 179 in modern subjects, and 37 in classics. It must not be supposed, of course, that we regard the growth of science teaching in comparison with other subjects as unsatisfactory; what we object to is the virtual limitation of science in secondary schools to chemistry and physics, or to botany in girls' schools. Science, up to the standard of the First School Examination, should be of a more cultural, and less specialised, scope: it should be science for all, and not science as preliminary training for a university course.
In training colleges where students are working towards a degree, and in secondary schools, courses are framed with a view to the requirements of a university. Indeed, in some secondary schools the work is of a sufficiently advanced character to justify representations to the university that many students under existing regulations do no more than mark time in their first year of residence. Such an organisation of courses is justifiable only in so far as the aim of the university, the training college, and the secondary school is entirely identical. The university in its science courses aims at turning out men, especially those who seek honours, who have attained a more or less high degree of specialisation. But the aim of the secondary school in framing its courses, save for the exceptionally gifted intellectually or the favoured few whose means allow, should be to turn out pupils who are fitted to take their place as citizens intellectually equipped for the average life of the community. Still more does this apply to the elementary school. A fortiori, the teachers should be fitted by their own training to educate their pupils to that end. It is by no means clear that such highly specialised courses as chemistry and physics, still less perhaps biology or physiology, framed with a view to the requirements of a still more highly specialised university course, are the best media through which school and training institution can best perform their function. With teachers themselves trained in highly specialised courses, we are in danger of a circle as narrow in its way as that of the older type of training.Of the importance of science in any modern system of education there can here be no question: but t*here is danger of a certain confusion of thought. The value of the practical application of science was fully brought out during the War; it has been apparent in many of the problems which have arisen since the War; while scientific men have repeatedly and justifiably urged upon the public and the Government the fundamental importance of the promotion of scientific research for all departments of the administration and life of the community and the British Empire. This insistence upon the value of science, aided by a confusion between instruction in science and a technical training, has obscured its true function as an element in the training of the average individual in preparation for his duties as a member of the community. Now that science enters so widely and so intimately into every department of life, especially in all questions relating to health and well-being, it is essential that both the individual who ultimately through the vote will control policy, as well as those by whom that policy will be framed and carried out, should have a general knowledge of the scope and aims of science, as well as of scientific method and the mode in which science envisages and attacks its problems. It is, however, beyond question that it should be a general knowledge on broad lines: a specialised training in some highly technical branch of science is neither needed, nor indeed is it desirable. The educationist need feel no alarm.
As a medium of culture, the history of scientific discovery opens up to the imagination vistas of man's endeavour which place it in the front rank of humanistic studies. Through a general familiarity with the methods of scientific observation and experiment in the various branches of research, may be developed a critical attitude in judgment, a power of observation, and a capacity for orderly arrangement; while a knowledge of the questions with which science as a whole is concerned in the past, present, and the future, fosters the broad outlook which, in combination with these qualities, is essential in successful dealing with the problems of life. We doubt, however, whether much of the science teaching in schools, either primary or secondary, could be regarded as science for citizenship instead of science for specialists; and we should welcome a movement which would broaden its scope and change its character.
ISSN:0028-0836
DOI:10.1038/120213a0
出版商:Nature Publishing Group
年代:1927
数据来源: Nature
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| 2. |
The Influence of Music on Behavior |
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Nature,
Volume 120,
Issue 3015,
1927,
Page 216-217
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摘要:
THIS book covers so wide a field that a review of it is far from easy. From the title-page we learn that it was " presented as part of the requirements for the degree of Doctor of Philosophy in the Department of Psychology of the University of Cincinnati." The last chapter perhaps provides the key to the book's construction; it consists of a report of the writer's own experiments on the subject carried out during the year 1921-22 in that University. In the conduct of this research the author must have found it necessary to acquaint himself with the accounts of previously published work; the penultimate chapter, entitled " The History of Experimental Work on Reactions to Musical Stimuli," embodies the results of his extensive reading. Having proceeded thus far, he began to collect the published material concerning the influence of music on work and on the sick, the use of music in magic and in myth, and the reactions of animals to music. These (in reverse order), together with a lengthy introduction, are the titles of the remaining six chapters of the volume.
The core of the book-the record of the author's own experiments on the physiological effects of music-is as unsatisfactory as might be anticipated from a young tyro's attempt to deal with so extremely difficult a subject. One might have felt tempted to regard these early efforts as prolegomena to more mature research to be expected from him in the future. But Dr. Diserens is now (so we learn from the title-page) assistant professor of psychology in his' old University; and, more Americano, it seems only too likely that he will be fully occupied henceforth in giving lecture courses, taking practical classes, and supervising crude research work, similar to his own, conducted by future aspirants for the doctorate in philosophy.Yet Dr. Diserens has done good service in publishing the results of his wide reading. It may be objected that the data on which he draws are of very different value-good, bad, and indifferent -and that they might well have been supplemented with more adequate criticism than is here given them. On the other hand, there is not in existence any book containing so extensive a bibliography as this oil the subject. The author, therefore, deserves our gratitude alike for his attractive literary style, and for having collated the results of previous workers, many of them from somewhat inaccessible sources, which had not previously been brought together in one volume.
When we read Dr. Diserens' review of the long line of experiments which have been attempted to determine the influence of music on such animals as the cobra, rattlesnake, lizard, pigeon, quail, pelican, mouse, rat, hare, squirrel, antelope, elephant, lion, tiger, coyote, monkey-not to mention many others-we are struck with the lack of previous training among the investigators in the methods of experimental psychology. The experiments might have been devised by the ' man in the street,' without any attempt to distinguish between the effects of music and those, say, of strangeness of the sound, wonder as to its source, curiosity in the movements of the performer, etc. But even if these precautions had been taken, it is doubtful whether a more satisfactory result than that reached would have been attained, namely, that animals vary widely in their response, according to their species and according to the kind of music to which they are subjected.Substitute ' individual' for ' species,' and this is precisely the result of the many, often equally uncritical, experiments that have been performed on man. All that can be said in the case both of animals and of man is that music may act as a sedative, or as an excitant, or as a stimulant to uncongenial work. Dr. Diserens shows how in primitive magic music usefully serves to enhance bodily energy and to give the magician a feeling of increased power. He brings forward evidence which indicates the semi-magical nature of many work-songs in primitive people. He also rightly distinguishes in such music the different functions of rhythm, melody, and words, the first eliminating, he believes, " the strain of voluntary attention," and encouraging synchronous regular movements, the second releasing reserves of energy, and the third giving relief by reference to the desires and conflicts of the worker.
" At present," Dr. Diserens concludes, " we only know that music does influence the reactions belonging to work, but we cannot as yet control such effects with such certainty as to warrant general industrial use." But here, again, the few experiments which can be adduced have not been carried out under sufficiently stringent conditions. The data quoted in regard to the results of sorting the mail to music at the Minneapolis Post Office are not in themselves adequate to convince the trained psychologist that, as Dr. Diserens maintains, they show " that music will cause ordinary mail sorters to do more work and make fewer errors than usual." The influence of foreknowledge, suggestion by the investigator, and many other sources of error need to be eliminated in order to produce conviction. Nor is the author's acquaintance with modern statistical methods assuring when he concludes, from the data published by him on the effects of bicycle-racing with and without the accompaniment of music, that " the results seem to indicate a distinct stimulation of the athlete by musical stimuli."The truth is that music exerts so many different responses-by its direct physiological effects, its arousal of imagery and association, its acceptance as purely musical meaning, as having a personified character, etc.-that different kinds of music cannot fail to produce different effects in different individuals, and that the same music may produce different effects at different times in the same individual.
This brings us to the problem-what is music? Dr. Diserens maintains that intervals and chords do not present " genuinely musical situations," and that children and savages '' delight in sound or colour combinations which pain the cultivated ear." Both these statements may be questioned, so far as the aesthetic attitude-regard for beauty-is concerned. Among the phonographic records employed by the author in his own experiments occur "Rosy Cheeks Fox Trot," " Dixey Medley" (banjo solo), and " Infanta March " (banjo). We wonder whether even the very highest powers of adaptation (the lack of which caused the works of Beethoven and Mozart, as well as Wagner and more modern innovators, to be characterised as unmusical when first they appeared) would enable " the cultivated ear " to designate these as aesthetically musical!We may illustrate this difficulty by reference to the author's own experiments on the influence of music on the rate of respiration. He concludes that music, whether fast or slow, " accelerates respiration." But when we find that of the four records of ' fast' music which he uses, two-both banjo records-were disliked by three of the eight subjects and were by other subjects termed distracting, we may well ask, How, then, can we be sure that the influence of such records on respiratory rate is due to their musical character?
The whole subject-the effect of music on behaviour-needs to be attacked in a more thoroughgoing, systematic way. Yet, for the reasons already given, the psychologist is grateful to Dr. Diserens for his book.
ISSN:0028-0836
DOI:10.1038/120216a0
出版商:Nature Publishing Group
年代:1927
数据来源: Nature
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Metallographic Researches: Based on a Course of Lectures delivered in the United States in 1925 |
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Nature,
Volume 120,
Issue 3015,
1927,
Page 217-219
W.ROSENHAIN,
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摘要:
THE practice which has been developed of late years in the United States of inducing a European metallurgist of standing to give courses of lectures on his own researches at various centres is certainly an excellent one. Not only does it bring American metallurgists and students of the subject into personal touch with men wh'o would otherwise remain nothing but names to them, but it also brings the trans-Atlantic visitor into touch with American affairs and institutions and sometimes engenders a higher degree of respect for them than had previously been entertained. Most of the lecturers thus brought to America have been British, but recently Dr. Carl Benedicks of Sweden and the German metallurgist, Dr. Guertler, have been included in the list. In the case of Dr. Benedicks, the subject matter of the lectures given has been put into book form under the title at the head of this notice.
Dr. Benedicks is of course a metallurgist and physicist of high standing, and the subject matter of his lectures accordingly attains a high level, although that level varies considerably between the different lectures reproduced in this book. Some of these-such as that dealing with the improvement of high-power photo-micrography of metals by means of the ' epiphragm '-have already been published in Great Britain, and so has much of his work on the ' homogeneous thermo-electric effect.' Another of his chapters is purely historical, and while we may understand his desire to secure recognition for a hitherto obscure Swedish metallurgist as the first observer of the Ac points in steel, this is not a matter of very wide interest. More directly important is the account of an attempt to determine the specific gravity of molten iron, an attempt which has met with a degree of success which is highly creditable when the extreme difficulties surrounding such experiments are considered.Of much more general interest are the two chapters dealing respectively with a kinetic theory of the constitution of solid matter and with the hardening of steel and other alloys. In the first of these Dr. Benedicks puts forward a kinetic theory of the space-lattice which is of essentially physical rather than purely metallurgical interest. Indeed, it appears to have been evolved in part at least in order to account for the thermo-electric effects which the author claims to have established. It does not seem, however, that Dr. Benedicks' views really take us much'forward: He objects to the suggestion that in addition to an attractive force-field surrounding ail atom there should also be a repulsive field. He suggests that no repulsive field is needed to account for the properties of gases and liquids on a kinetic theory, and that its introduction in the case of solids is equally unnecessary. According to this view, the atoms have no equilibrium position on a space-lattice, but merely a mean position which results from continual mutual collisions. That collision and rebound imply repulsive forces is, of course, obvious, but the suggestion is that these repulsive forces come into action only on actual contact. What, however, is really meant by ' contact ' in the case of such a system as an atom is believed to be? Presumably, repulsion results from some sort of deformation produced in the atoms by their mutual forces, but it is difficult to believe that such deformation only becomes sensible at the instant when the outer electron orbits overlap or touch.
Perhaps the most interesting deduction drawn by Dr. Benedicks from his kinetic theory is that of the ' phorctic electron ' mechanism of electric conduction. According to this view, electrons pass freely from atom to atom only when the outer electron orbits are in contact, and since the amplitude of atomic vibrations increases with" rising temperature, there is a decrease of conductivity with rise of temperature. One difficulty of this theory, however, is that there does not appear to be any reason why this effect should not be of the same order in alloys as. in pure metals, so that the low temperature coefficient of resistivity of solid solution alloys is not explained. Dr. Benedicks also attempts to explain super-conductivity at very low temperatures by the suggestion that at those temperatures the atoms become ' agglomerated,' i.e. remain in continuous contact, and therefore electrons can pass from atom to atom without resistance. This would be an excellent explanation if all metals and alloys became super-conducting when at temperatures near the absolute zero, but in fact the phenomenon is confined to a few metals only.These somewhat important examples of the failure of Dr. Benedicks' theory suggest that it requires much further consideration before it can be seriously put forward, and it seems rather a pity that it should have been made the subject of an educative lecture in America-at least in its present form.
Criticisms of a similarly serious nature can be brought against Dr. Benedicks' treatment of the theory of hardening of steel arid other alloys. The view of the nature of hardening by the breakdown of a super-saturated solid solution and the resulting formation of finely dispersed particles of a ' precipitate ' in the solid matrix is dismissed by the Swedish metallurgist on the ground of certain measurements of the electrical resistance changes in alloys during the course of hardening. It is a well-known fact that an element present in solid solution causes a far greater increase in electrical resistivity than the same substance present in the form of separate crystals. It is argued, therefore, that the breakdown of a solid solution by the formation of minute ' suspended ' particles should be accompanied by a decrease in resistance. In fact, measurement shows that resistance increases up to the point where maximum hardness is attained and only then decreases.The argument just cited, however, is based on a fallacious assumption, namely, that the resistivity of a substance A in which particles of B are suspended is independent of the dimensions of the particles. Actually, we have no experimental basis for that assumption, and there is, on the contrary, good reason to suppose that the presence oof very minute suspended particles may produce a higher resistivity than the same material in atomic dispersion, in solid solution. According to the lattice distortion theory put forward by the writer some years ago, the high resistivity of a solid solution is due to the distortion of the lattice caused by the presence on it of the solute atoms. This also causes a certain moderate amount of hardening. But when such a composite lattice begins to break down, the first effect-which must in fact incre.ase until all the solute atoms have begun to travel towards a state of separate aggregation-must be a partial breakdown of the parent lattice, and it is this further disturbance of the parent lattice which will produce both mechanical and electrical hardening, i.e. increase of resistivity.
On this view, resistivity and hardness should attain their maximum at about the same stage and should then decline together, as experiment actually shows. Now, what is Dr. Benedicks' alternative? He draws an interesting distinction between a ' super-cooled ' and a ' super-saturated ' solid solution, although it seems doubtful whether such a distinction has any real meaning. He further suggests that, in a freshly quenched alloy or an austenitic steel, we have a super-cooled but not a super-saturated solid solution, and that age-hardening in the alloys or the corresponding process in austenitic steel results from a transformation from the super-cooled to the super-saturated solution. Now it is well known that by rapid cooling and other means a super-saturated solution can be maintained without crystallisation, but it is quite another matter to suppose, as Dr. Benedicks does, that a super-saturated solution can be formed by transformation. The writer respectfully suggests that if a super-cooled solution, whether solid or liquid, is caused to undergo transformation, the result will never be the formation of a supersaturated solution, but a separation into two phases. Somewhat similar criticism can be applied to Dr. Benedicks' remarks on hardening by cold work. This he ascribes to the production of multiple twinning, in spite of the facts1 that in copper and copper alloys the existence of twinned crystals confers no sign of hardness, while observation shows that twin lamellae offer no obstacle to crystalline slip. Further, mechanical twinning is unknown in alpha-iron, yet that metal hardens vigorously under cold work. It would thus seem particularly unfortunate that Dr. Benedicks should have put before his American hearers a series of views so markedly at variance with those held by British and American metallurgists, while leaving his views open to such obvious and, in the writer's opinion, fatal objections. This is the more the pity, since Dr. Benedicks' contributions to metallurgy are so important that he should have had no difficulty in providing his audience with sound, well-established material, such as is to be found in his. chapter on meteoric iron and invar, on a ' rational' section for ingots intended for cold-working, and on the ' hot wall' effect in corrosion.
ISSN:0028-0836
DOI:10.1038/120217a0
出版商:Nature Publishing Group
年代:1927
数据来源: Nature
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| 4. |
Principles and Practice of Mosquito Control: being a Handbook to the British Mosquito Control Institute |
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Nature,
Volume 120,
Issue 3015,
1927,
Page 219-220
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摘要:
FROM the British Mosquito Control Institute at Hayling Island, Hampshire, has been recently issued this handbook on the principles and practice of mosquito control, which includes also a brief account of the inception of the Institute and of the results of its work. The Instit'ute owes its existence to the success of an anti-mosquito campaign which was initiated at Hayling Island in 1920 to deal with the local mosquito nuisance which had become so intolerable that the inhabitants of the central residential district found it impossible to sit in their gardens in the late afternoons or in the evenings. Mr. F. W. Edwards, of the British Museum (Natural History), expressed the opinion that the trouble was probably due to the salt-marsh species Aedes (Ochlerotatus) caspius and A. (0.) detritus, and examination of some thousands of adult mosquitoes captured in the residential area during September and October proved that the latter species was almost entirely responsible. To Mr. John F. Marshall belongs the credit of beginning in 1920 investigations preliminary to the inauguration of methods of control. In April 1921, at a meeting of some seventy inhabitants, it was decided to institute a systematic campaign against the mosquitoes; committees were elected to deal with the various branches of the work, and a circular was issued to every householder on the island explaining the objects of the campaign and appealing for the assistance of voluntary workers and for financial support. A laboratory was improvised by Mr. Marshall, where mosquitoes could be examined and investigations on their breeding habits carried out.
Larvae of Aedes detritus were found in 1921 in enormous numbers in certain accumulations of stagnating and partly salt water about a mile and a half from the centre of the residential district, and in the summer and autumn of that year several of these breeding places were permanently abolished, while a large number of others were treated with paraffin or with larvicides. During the next three years the work of abolishing or controlling the mosquito breeding areas was continued, and the nuisance progressively decreased and eventually disappeared. Evidence of this was furnished by a postcard ' canvass ' of the residential district in October 1924, as well as by the fact that residents were able, for the first time in many years, to sleep out of doors. The inconvenience due to insufficient accommodation for the work in progress was severely felt, and Mr. Marshall generously erected at his own expense a separate building in which the various branches of the work could be adequately developed.This building-the Institute-which was formally opened by Sir Ronald Ross in August 1925-contains eleven working rooms, and cost with its equipment about £4200. It is hoped that a scheme for establishing the organisation upon a permanent basis may eventually be devised, and in preparation therefor the Institute has been incorporated. Up to the present the Institute has not received financial assistance from official bodies or local authorities-excepting a grant of £100 from the Ministry of Health in. 1923 towards the cost of labour employed in certain experimental work- but has had to rely on voluntary contributions. An appeal is now issued for subscriptions-life members' and annual-and for donations to provide an annual income which will enable the work of the Institute to be carried on efficiently.
The success of the work on Hayling Island directs attention to the desirability of suppressing mosquitoes which, when present in numbers, cause general annoyance by their bites, which are frequently followed by the development of sores and sometimes by even more serious consequences. These effects may be produced by Culicinc as well as by Aiiopheline mosquitoes. This aspect of mosquito control is emphasised by the recent decision in the ' Paisley Case ' (see NATURE, June 25, p. 934), the first of its kind under the Public Health Acts in Great Britain, in which the sheriff found that certain ditches had become so encumbered with silt and vegetation as to be ineffective as water courses and that the ditches and the adjacent overflowed ground had become a breeding place for large numbers of mosquitoes, and he ordained that the owners should clear the ditches and maintain them clear.Communities which may decide or be compelled to undertake mosquito control would do well to consult this handbook for the sequence and nature of the operations and to base their methods, as at the Hayling Institute, on a true scientific foundation. For example, there are twenty-five species of mosquitoes in Britain which differ considerably in their habits, and in the period of hatching out, so that it is necessary to discover first the species which arc prevalent in the district, to estimate which is the most important and should therefore be first attacked, and to see that waste of effort is avoided, for example, by treating with larvicide only the water in which larvse have been actually observed. Useful suggestions are given for inspecting possible breeding places, for applying larvicides, for ' unstagnating ' the water, and for recording progress in a central institute.
There will always be, as is pointed out in the handbook, a certain section of the public who will refuse to assist in the work of mosquito control, maintaining that the task is hopeless. This attitude of mind should be dealt with, as in the first year or two at Hayling Island, by the education of public opinion by means of demonstrations of living and preserved specimens of the local mosquitoes and of diagrams illustrating the progress of the campaign.The handbook is illustrated by excellent photographs prepared by Mr. Marshall, and by useful diagrams which help the reader to recognise the more important larvae and adults. But its principal value is as a record of the means by which the'serious nuisance due to mosquitoes was overcome within four years in a somewhat difficult terrain-a noteworthy achievement on which the director and his collaborators are to be warmly congratulate
ISSN:0028-0836
DOI:10.1038/120219a0
出版商:Nature Publishing Group
年代:1927
数据来源: Nature
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| 5. |
(1) The Pulse of Progress: including a Sketch of Jewish Theory (2) Climate through the Ages: a Study of the Climatic Factors and their Variations |
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Nature,
Volume 120,
Issue 3015,
1927,
Page 220-221
J. W.GREGORY,
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摘要:
MR. ELLSWORTH HUNTINGTON, of the -1VJL Geographical Department of Yale University, in a series of thirteen interesting volumes, besides numerous papers, has ingeniously and eloquently advocated the view that in the environment of which man is the creature, climate is the most powerful factor. As a corollary to this view he holds that climatic changes are the main cause of the rise and fall and of the migrations of civilisation. In the present work he puts his theory in a more attractive form as he limits the climatic pulse in historic times to a comparatively narrow beat, as he explains the vicissitudes of ancient Greece by climatic influences of the order of a change of mean temperature of the year from 62° E. to 63-1° E., with a variation of humidity of 10 per cent. To determine ttie mean annual temperature within 1-1 °F. is practicable for few countries only; and it would be impossible to prove or disprove so slight a change for any country except within recent times. That climate is an important factor in human welfare, and that people's working efficiency varies with weather, is universally recognised; and these facts are confirmed by the interesting statistics brought forward by Mr. Huntington from American industrial and educational records. It may nevertheless be doubted whether the climatic changes in historic times have been the main factor in the migration of races and civilisations.
Mr. Ellsworth Huntington's books are always interesting, for he is graphic and collects striking examples from a wide range of evidence. His information is obviously of very unequal value, but he consoles himself with the reflection,'' Perhaps your answer is wrong, never mind." Perhaps on that principle he retains the generally rejected explanation by Dr. W. H. S. Jones that the decay of Greece and Rome was due to an increase of malaria owing to a decrease in rainfall.The new ground covered in the " Pulse of Progress" is the application of Mr. Huntington's principles to the natural history of the Jews. He has restudied the Bible and its newer crtfeicism, and has re-written the Bible story in accordance with the geographical control of physical agents. His version is like that of the "Darkie Sunday-school":
" Bring yer sticks o' chewey gum and sit upon de floorAnd I'll tell yer Bible stories dat yer never heard before."
His account of Jewish history is not likely to be reprinted in Great Britain by the Sunday School Union, but is in accordance with the general trend of advanced Biblical criticism. He points out, for example, that the plagues were the natural result of a succession of low Niles. His account, however, shows that the climate of Palestine and Egypt has been practically unchanged throughout historic times, except for the minor fluctuations that are inevitable owing to the complexity of the factors that control weather. The volume includes an interesting chapter on what Mr. Huntington describes as the suicide of Russia by the expulsion of its aristocracy and the massacre of more than a million of the more intelligent citizens. Australia he describes, on the other hand, as having " evolved a social and political system which is pre-eminent as one of the important recent contributions to human progress."One of Mr. Huntington's most striking contributions to climatic variations within historic times has been deduced from the variations in rate of growth of the big trees of California; their evidence is complex, as different trees did not vary in the same way simultaneously, and their records require a lot of interpretation to make them tell the same tale. Their restricted distribution, as pointed out by Dr. G. C. Simpson in a weighty article reprinted by Mr. Huntington, proves that there has been no serious change in the climate of the belt occupied by these trees during the past 2800 years. Mr. Huntington has introduced one correction on the interpretation of the big tree records, based on evidence from the Caspian. This correction is rejected by Dr. C. E. P. Brooks in (2) " Climate through the Ages," althoiigh' he supports Mr. Huntington's main thesis by accepting important changes of climate within the historic period. Dr. Brooks holds that major climatic changes are due to the interaction of many geographical causes and that former glaciations and warmer periods were the result of the different distribution of land and water; but as there has been no appreciable change therein during the past 2000 years, he assigns the climatic variations during historic times to solar activity. According to his view, climate is under solar control when land and water are stationary.
Dr. Brooks compares the evidence of the big trees with the variations of the nearest salt lakes. The country in which they occur must have had a wet climate during the glacial period, which was followed by a dry warm interval, before another cold wet episode. The evidence is not altogether harmonious, for the lakes indicate a maximum rainfall at 1000 B.C. (p. 393), which was followed by a dry period until A.D. 800; according to the big trees, the wettest time was between 480 and 250 B.C., and it was followed by drought until A.D. 850. Toward the end of this time the climate was so warm that, according to Dr. Brooks, there was no perennial ice in the Arctic Ocean in the seventh century and none at all in the Greenland seas. Since then, the Norse colonies have been frozen out by increasing cold. Dr. Brooks connects this change with the end of a warm dry period in Britain in the ninth century and the final deterioration of the British climate about A.D. 1000. That the climate of Greenland has become more severe in recent times is indicated by weighty evidence; but a change of this extent in the Arctic Ocean would surely have been accompanied by greater changes in the British climate, and it is contradicted by the evidence of the Sagas. The frequent assertion that the British weather has become milder instead of more severe during the past eighteen centuries is opposed to any fundamental change in the Arctic Ocean.The effect of geographical changes in climate naturally leads to a discussion of the Wegener theory of continental drift, which has received most support from the meteorologists; and it is interesting to note that Dr. Brooks emphatically rejects it as unnecessa
ISSN:0028-0836
DOI:10.1038/120220a0
出版商:Nature Publishing Group
年代:1927
数据来源: Nature
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| 6. |
Industry and the State: a Conservative View |
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Nature,
Volume 120,
Issue 3015,
1927,
Page 222-222
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摘要:
THIS book is an interesting expression of the views held by what may be termed the left wing of the British Conservative Party. Opposed on one hand to laissez-faire as on the other to socialism, it seeks a via media between these conflicting extremes. The authors are convinced that an advance in the economic status of the wage-earning classes is the necessary corollary of their advance in political status, and they seek the means whereby the improvement may be effected. Their suggestions do not partake of novelty, but they are urged with some force and ardent conviction. For the planning of economic policy they would have an. Economic General Staff. Industrial Councils and Wage Boards would be created with increased powers; and co-partnership would be made an essential part of industrial organisation. The writers have read widely, and. there is throughout an air of attractive goodwill about their proposals. How far they are likely to attract attention is another matter. Much, for example, of the recent legislation they quote in support of their views is open to a different interpretation from what they place upon it. Their account of the characteristics of industrial ownership follows that of an American, Mr. Robert Brookings; but if they had considered the arguments of Prof. Henry Clay, they would have seen that most of the inferences they draw are quite misleading. Their insistence that there is an incompatibility between socialism and private property is contradicted by the work of Mr. and Mrs. Webb and Mr. R. H. Tawney; they do not seem to grasp the distinction made by most socialists of authority between property as use and property as control. But their book is doubtless meant to be no more than a tentative sketch; and as such it is an interesting expression of a significant tendency which is not unlikely to grow.
ISSN:0028-0836
DOI:10.1038/120222b0
出版商:Nature Publishing Group
年代:1927
数据来源: Nature
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| 7. |
Monograph of the Sea Snadles (Hydrophiidœ) |
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Nature,
Volume 120,
Issue 3015,
1927,
Page 223-223
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摘要:
THIS' work in its scope and arrangement follows the lines of the British Museum Catalogues; the greater part of the text is purely systematic in nature, but the author's views on the relationships of the group and some notes on habits are included in the introduction. The list of references under each specific heading is not supposed to be exhaustive, but an attempt has been made to include all those of any importance from which the student may obtain any additional information he may require. The book will be welcomed by all systematic herpetologists as the first complete account of the Sea-snakes since the publication of Boulenger's " Catalogue of Snakes " (1896); based on the largest collection of these animals that has yet been brought together, the author's views carry weight and conviction. The most important proposed change is the recognition of two sub-families, the Laticaudinse of Australian origin aild the Hydrophiinse of Lido-Malayan seas; these two sub-families are established chiefly on osteological features of the skull and are regarded as two separate evolutionary lines. The author's conception of the genera agrees closely with that of Boulenger, but he finds that many of the species recognised by the latter are untenable; the names used are for the first time brought into line with the International Rules of Zoological Nomenclature.
ISSN:0028-0836
DOI:10.1038/120223b0
出版商:Nature Publishing Group
年代:1927
数据来源: Nature
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| 8. |
The Constitution of Ordinary Lead |
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Nature,
Volume 120,
Issue 3015,
1927,
Page 224-224
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摘要:
AFTER repeated failures I have at last succeeded in obtaining the mass-spectrum of ordinary lead. This has been done by the use of its tetramethyl compound, a pure specimen of which was kindly supplied me by Mr. C. S. Piggot, of the Geophysical Laboratory, Washington. The vapour was first used diluted with carbon dioxide but later was admitted pure into the discharge tube. It works smoothly, but very long exposures are required. The three principal lines are 206 (4), 207 (3), 208 (7). The figures in brackets indicate roughly the relative intensities and are in good agreement with the atomic weight 207.2. This group is beautifully confirmed by its repetition 15, 30, and 45 units higher, corresponding with the mono-, di-, and trimethyl molecules. Comparator measurements show that all three of these lines are integral with those of mercury to an accuracy of 1 or 2 parts in 10,000.There are indications that many other isotopes may be present in small proportions. An exceedingly faint line at 209 occurs in the atomic group, and on one plate is visible on the PbCHs group. This is almost certainly an isotope. Search for lighter mass numbers in the atomic group is unfortunately impossible owing to the mercury group and ita penumbra. It was hoped that definite information would be available from the PbCH3 group, but tho unexpected appearance of lines certainly due to HgCH3 complicates this region too. The evidence suggests the possibility that 203, 204, and 205 are all present in small proportion, but certain proof will only be available when mercury can be eliminated from the discharge.
The mercury lines in these experiments were more intense than any previously obtained, and indicate with certainty the presence of a seventh isotope Hg196. Comparative exposures show that this is present to the minute extent of 0'04 per cent.
ISSN:0028-0836
DOI:10.1038/120224a0
出版商:Nature Publishing Group
年代:1927
数据来源: Nature
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| 9. |
Chromium-plating and Resistance to Corrosion |
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Nature,
Volume 120,
Issue 3015,
1927,
Page 225-226
H. C. H.C.,
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摘要:
MR. WERNICK has performed a service in stating his experience on the degree of protection to be expected from electro-deposited chromium. Much of what he says is quite true, and indeed there is no disagreement between his experience and the guarded statements on this subject made by Mr. Evans in his book, and in my review of it to which he refers. Thus Mr. Evans states (page 208): “Chromium-plated articles which are now being manufactured in this country are said to withstand sea-water and tarnish”; and again, “The problem has been attended by many difficulties, some of which have not wholly been overcome as yet”. In my own review I wrote, “It is stated that plated articles manufactured in this way withstand corrosion. …” Mr. Wernick seems to assume that Mr. Evans and I have expressed an opinion in favour of chromium more definite than is actually the case.It must, however, be emphasised that several workers who have tested chromium-plating have published the view that, if the plating is satisfactorily performed, it does give considerable resistance to corrosion. References to these are given in footnote No. 2, p. 208, of Mr. Evans's book. Some of them may not be entirely unprejudiced, but taken as a whole they cannot be neglected. No doubt the results, as Mr. Wernick says, are somewhat variable. This is true of any new process. In the July issue of Industrial and Engineering Chemistry, Killifer has published ah article in which he definitely recommends chromium-plating as a means of combating cases of corrosion which are encountered in the chemical, oil, and paper industries. In the course of this he states that the unsatisfactory results obtained with early samples of chromium-plating were due to pin-holes.
With reference to the question of the direct deposition of chromium on steel, Ollard, who has done so much work on the question of the adhesion of many sorts of depositions, stated at the British Association in 1925 that " the best results were obtained if the steel was first coated with nickel or copper." If Mr. Wernick has obtained better adhesion by depositing chromium direct, he has achieved a considerable success, and it is to be hoped that he will publish his method in full, if he has not already done so.So far as I have been able to ascertain, his statement that "the salt-spray corrosion test may . . . betaken as a particular simulation of marine conditions," does not command general acceptance. I have consulted Dr. Bengough, who has had wide experience of this test, and he informs me that it. all depends on how it is carried out. It was introduced by the Bureau of Standards, and as carried out by them certainly did not simulate marine, conditions, since the articles in question were exposed to salt spray kept permanently moist. If the test is modified so that the articles are alternately wetted with salt spray and dried al.in.-torvals, a nearer approximation to marine eoiidjLtions is obtained. Salt spray, however, is no I sea-water spray. The latter contains a variety of salts, and some colloidal substances. A still Closer approximation is furnished by using sea-water' spray with alternate wetting and drying. Even this, however, is not the same as marine conditions themselves. Dr. Ben-gough's view is that no artificial test of this kind which has yot been devised can really take the place of natural marine conditions.
Mr. Wernick's statement that chromium may act as a cathode against iron is very probably true. Certain chromium alloys do behave in this way. Chromium-plating is therefore comparable to nickel-plating rather than to 7,inc-plating. The question is, is it better to plato with a cathodic material such as nickel or an anodic material such as zinc? The cathodic material will only protect if it is non-porous'.Most electrolytic deposits are porous, but if they are hard the porosity can be greatly reduced by polishing. A view widely held by those with a practical experi ence of plating is that the protective qualities of nickel are largely connected with the fact that it can be well polished. Chromium deposits should have the same character. Anodic coverings such as zinc will pro tect iron even if porous, but only at the expense of the zinc. The protection will continue until the zinc is used up by the anodic corrosion. It is not difficult to understand why salt-spray tests give good results with zinc-covered articles, but it does not follow that these would have a long life in a marine atmosphere, because the rate of attack of zinc by sodium chloride solution in the presence of oxygen is very rapid, as
ISSN:0028-0836
DOI:10.1038/120225b0
出版商:Nature Publishing Group
年代:1927
数据来源: Nature
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| 10. |
A Relic of Sir Edward Frankland |
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Nature,
Volume 120,
Issue 3015,
1927,
Page 226-226
W.F.,
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摘要:
IN “Sketches from the Life of Edward Frankland”, printed in 1902 for private circulation (Spottiswoode and Co., 1902), and which for the greater part is his autobiography, reference is made to his apprenticeship days in Lancaster.Frankland mentions a " delightful occupation devised to prevent my idle hands from finding ' some mischief still'; . . . this was the making of mercurial ointment.
" In a room on the first floor there was a very large marble or serpentine mortar, about 2 feet internal diameter. The pestle was about nine inches in diameter and one fool long, with a wooden shaft about six feet long securely fixed into it, its other end working loosely in an iron ring fixed to a beam in the ceiling. Thus the pestle coxild be worked round and round and backwards and forwards in the mortar." For the preparation of mercurial ointment, about fourteen pounds of hog's lard and five or six pounds of quicksilver were placed in this mortar and had to be triturated until a magnifying glass failed to show any globules of mercury. This blending of mercury with lard is an exceedingly tedious operation; working, in the aggregate, two full days a week, it required about three months to complete it. Moreover, the resistance to the motion of the pestle in the lard is very great, making the labour very hard and the arms ache."
Owing to a rumour that a relic of Sir Edward Frankland might still exist in Lancaster, the writer called on the present owner of the promises at which Frankland served his apprenticeship (Mr. A. H. Robertson) and was shown the mortar and pestle situated exactly as described above, covered with the dust of ages, in the semi-darkness of a small upper room where one could visualise the apprentice and his successors grinding in the true ' Mantah'ni ' spirit of sxibmission.Fig. 1.-Room at Lancaster with pestle and mortar used by Sir Edward FYaiikbmd.
Mr. Robertson has generously presented the mortar and pestle to the Lancaster Museum, where it will shortly rind a permanent home.The accompanying photograph (Fig. 1) showing the old mortar and pestle in situ was taken by Mr.Wynespeare Herbert of Lancas
ISSN:0028-0836
DOI:10.1038/120226a0
出版商:Nature Publishing Group
年代:1927
数据来源: Nature
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