doctrine of evolution is, until he has had an objective study in at least some narrow field of research.

The new questions and accessory principles which are rapidly springing up about the central doctrines of evolution are pretty well set forth in the seventh chapter, entitled 'More recent attempts to explain evolution.'

The last chapter is on the evolution of man, and it is altogether unsatisfactory. It seems to have been written as a logical complement to a work on animal evolution, but it deals rather more with moral and metaphysical speculations than with the facts of the science. So far as it treats of human evolution, aside from its speculations, it refers simply to the animal man in his zoologic relations. Human evolution, that is, the development of those characteristics which make man man, — the growth of human activities, - is ignored, and yet this is the largest subject in the literature of the world, embracing, as it does, the evolution of arts, the origin and development of institutions, languages, philosophies, or opinions, and all modern scientific psychology.

But a very small part of human evolution is embraced in theories of man and monkey kinship. The origin and growth of the humanities, i.e., those things which characterize humanity, have always been the subject of history; and all history is now in process of reconstruction upon a sounder theory than any which has hitherto obtained, and every writer in his own field postulates evolution by discussing the origin and development of the art, the institution, the language, the philosophy, or the psychic operation of which he treats. J. W. POWELL.

SIDGWICK'S HISTORY OF ETHICS. THIS little book by Professor Sidgwick is a reprint of his article on ethics in the Encyclopaedia Britannica,' with considerable alterations and additions. As originally published in the encyclopaedia, it was necessarily quite condensed in style, and it still retains that character to a great extent, thus presenting a much greater quantity of matter than is usually found in books of the same size.

The work is designed especially for students, and it seems to us admirably adapted to its purpose. The compression of the style is perhaps a defect from a literary point of view, but this is of little consequence in a text-book. The work is divided into three parts, treating of Greco-Roman, Christian, and modern ethics respectively. It is evidently based, as the author himself says, on

Outlines of the history of ethics for English readers. By HENRY SIDGWICK. London, Macmillan, 1886. 12°.

a thorough study of the original authors, only certain small portions, chiefly in part ii., being written at second-hand. It is marked, too, by almost perfect impartiality, a merit of the first order in an historical work, but at the same time one seldom found in so high a degree. The author has been engaged in controversy with many ethical writers, and it might have been thought that a history of ethics from his pen would partake of the same character. On the contrary, it is devoted almost exclusively to the work of exposition, with only occasional criticisms when they seemed really required to point out serious defects in the systems described.

In the first part, attention is mainly directed to the three great ethical philosophers of ancient Greece, Socrates, Plato, and Aristotle; and, though less than fifty pages are devoted to them, their modes of thought, their leading doctrines, and their relations to each other, are very clearly brought out. The author also traces the connection between all the Greek ethical systems, and shows in an interesting way "how, from the spring of Socratic conversation, flowed the divergent streams of Greek ethical thought." The second part of the book is much shorter than either of the others, as it should be; for, whatever may have been the influence of Christianity on practical morality, it can hardly be said to have contributed much to ethical philosophy. In treating of modern ethics, Professor Sidgwick confines himself in the main to English philosophers, on the ground that his work is intended for English readers, and that English ethical thought has developed itself, for the most part, independently of foreign influence; to which he might have added, that English ethical philosophy is by far the most important that has appeared in the world in modern times. The doctrines of the various English philosophers are briefly but clearly outlined, and special care is taken to point out the positive contributions of each thinker to the ethical thought of the world. Professor Sidgwick's book can be heartily commended to all who wish for information on the important and fascinating subject of which it treats.

THE PSYCHOLOGY OF REASONING.

M. BINET, a prominent member of the Society of physiological psychology in Paris, has been busy for many years in experimenting upon hypnotic subjects, who seem to be so abundant and interesting in France. He has formed one of a small band of workers, with Charcot as their

La psychologie du raisonnement, recherches expérimentales par l'hypnotisme. Par ALFRED BINET. Paris, Baillière, 886. 12°.

head, who have brought to light many striking and remarkable facts about these abnormal conditions. This work suggested to M. Binet that some light might be shed on the nature of the reasoning process by observing the half-conscious actions of hypnotics; and the book before us is the result of this suggestion. The volume has been called out upon a slight provocation, and its argument in brief is as follows. A perception may be compared to the reading of a book : we attend to the sense, and not to the letters; we read something into these black marks. So, too, our sensations are taken, not for what they are, but for what they stand for, for what they tell.

By means of these perceptions the mind forms images, which are its fundamental elements. It is these images that form our stock in trade, and their prevalent nature determines many of our peculiarities of mind. They constitute one's mental background, one's apperceptive bent. These images come into combination and suggest each other as well as fuse together. The laws that condition this process are the laws of association of ideas, on which the English psychologists lay such stress. A close analogy can be traced between a syllogism and the process of perception: the perception is the conclusion; it expresses a judgment; it says, for example, this is an orange. The remembered images which enable me to recognize this as an orange play the part of the major premise, for this too expresses the results of past experience; and the minor premise which is brought into relation with the major by a certain similarity is the sensation itself. The analogy is closer than this crude outline indicates, and is really a highly suggestive view of the matter. It makes the syllogism the fundamental process of the human mind. It makes the triad, in which a middle term acts as the go-between for two others, of the utmost importance. This is the mechanism of reasoning, the general formula for getting valid deductions, as well as a fundamental natural process of the human mind. Man is thus in a new sense a rational animal; reasoning is a sort of new sense.

In the course of the development of this argument many interesting and valuable facts are brought out. It is only just to the author to notice a few of these. One result of his experimentation on hypnotics, and one physiological point, will serve as samples.

The subject, an hysterical young girl, was told that M. Féré (an associate of M. Binet) would be invisible to her. From that moment on, she ran against him, and thought it a miracle that she should be opposed by something she could not see: a hat on his head seemed suspended mysteri

ously in the air. At the close of the session they forgot to disabuse her of this forced idea, and three days later M. Féré was still invisible; and, what was more remarkable, it was found that she had lost all remembrance of him: she knew neither his name nor his person, although he had been her friend for ten years. When he was made visible, she did not recognize him. At this period she had an hystero-epileptic attack, and from then on, M. Féré was her old friend as before. This case is used to illustrate the law of regression, which requires the most unstable and latest acquired knowledge to go first in dissolution, and to be re-acquired last in evolution. The patient, in recovering, first recognized M. Féré as an object, then generally as a man, and lastly particularly as her old friend.

In discussing the topic of the criterion of the difference of two sensations, the point is made that two sensations are distinct when they have a different local sign, a differently arranged group of accessory, secondary sensations. Two compasspoints are felt as two when they have sufficiently different local signs. This local sign means that they can be localized. M. Binet tries the experiment, and finds that when two points are at such a distance apart as always to seem distinct when simultaneously touched, then, when either is touched separately, one can decide with confidence whether the touched spot is to the right or to the left, i.e., one can localize the sensation; but when the distance between the compass-points is less than this, the points are localized correctly only half the time, i.e., as often as the action of mere guessing would bring about. This point is a really valuable contribution to the psychology of touch. M. Binet's study can be recommended for its suggestiveness and the facts incidentally noticed, as well as for his ingenious analogies between psychology and logic.

J. J.

THE Medical and surgical reporter gives the following interesting facts concerning the watersupply of the European capitals: Rome heads the list with her 204,000,000 litres of pure water every twenty-four hours (her population being 345,036, every inhabitant can dispose of 591 litres per diem); London comes next, for every one of whose 4,085,040 inhabitants there are 300 litres daily; Paris takes the third place, her population amounting to 2,240,124, and each inhabitant having for alimentary uses 58 litres per diem, and for secondary purposes 169, - a total of 227 litres; Berlin has 1,302,283 inhabitants, with 140 litres daily to each; Vienna, 770,172, 100 litres each; Naples, 463,172, with 200 litres; and Turin, 278,598, with 98 litres a head every twenty-four hours.

FRIDAY, SEPTEMBER 24, 1886.

COMMENT AND CRITICISM. THERE IS NO MORE IMPORTANT SUBJECT for both thought and action than the wholesomeness of the milk-supply of our large cities. It has been estimated that in the city of Brooklyn the daily consumption of milk amounts to 152,575 quarts. A considerable part of this forms the sole food of thousands of children and invalids, and it is therefore of the greatest importance that it should be of the highest degree of purity attainable. The influences at work to deterioriate milk are manifold. The cows themselves may be affected with tuberculosis or some other form of disease which may by the medium of the milk be communicated to its consumer, or the sanitary condition of the stable in which these animals are confined may be so defective as to render the atmosphere impregnated with filth and the germs of decomposition, which act most perniciously upon the milk. In speaking on this subject before the Massachusetts medical society, Dr. B. F. Davenport called attention to the readiness with which milk will absorb impurities, and also to the fact that the milk which is delivered in Boston is, at the time of its delivery, nearly three days old, and that it has been exposed to such a probability of contamination as to be practically on the very point of souring. He attributes no inconsiderable part of the summer diarrhoea to this changed condition of the milk. Dr. Davenport believes that the difference in the coagulation of human and cow's milk in a child's stomach is owing to the difference in their chemical reaction; that of cows being acid, and the other neutral or slightly alkaline. If milk could be served to the consumers on the same day of its production, and in a condition free from all impurities, there is no doubt that this would be an important factor in reducing the sickness and death of the infantile population.

PROF. E. C. PICKERING, the director of the Harvard college observatory, has put forth a pamphlet in which he broaches a scheme which may result in much advantage to the astronomical world, and in time to the outer world, which is slowly

No. 190.-1836.

but surely benefited by all progress in science. The premises from which Professor Pickering starts are these: observatories with good instruments but no funds to pay observers, and good astronomers with no instruments or money to get them. Like all schemes of this day, Professor Pickering's is one of consolidation. He would have a fund raised the income of which should be available for paying the cost of astronomical work, whether it be done at Harvard, at the Lick observatory, or in Europe, -no matter where, so long as the workers were fit for their labor. As Professor Pickering is cognizant of the good results obtained with the Elizabeth Thompson fund for scientific investigation in general, being one of the trustees, we judge he must be encouraged to employ the same method in his own field. The plan as given in the pamphlet is one deserving the attention of all able to aid scientific work.

It

The Lick observatory, although so well equipped, is a case in point. Of the $700,000 given by Mr. Lick, $500,000 have been expended for the plant.' Although the whole plan of the observatory has been made with direct reference to keeping its running expenses low, it is clear that the company of astronomers will have to be kept small. would require a staff of at least ten astronomers to return the full results from the outfit, and at present not more than three can be employed. The work of these must be concentrated on the large equatorial, and even then their energies will not be sufficient to utilize every moment. Now, this is Professor Holden's plan, and we suspect he was hard-pressed to devise it: "We mean to put the large telescope at the disposition of the world by inviting its most distinguished astronomers to visit us one at a time, and to give to them the use of the instrument during certain specific hours of the twenty-four. Each day there will be certain hours set apart when the observatory staff will relinquish the use of the equatorial to distinguished specialists who will come from the United States and from Europe to solve or to attack some one of the many unsolved problems of astronomy. In this way we hope to make the gift of Mr. Lick one which is truly a gift to science, and not merely a gift to California and to its university."

IN A RECENT NUMBER of Science it was stated that cholera did not seem to be very active in Italy, although it had extended thence to Trieste and Fiume. From here it has invaded Carmola and Croatia. At Lie, a village of Croatia, it seems to have awakened to new life, developed doubtless by reason of the unsanitary condition in which it has found the inhabitants of that place, some nine hundred in number. Although it seems to have but just appeared in that place, ninety persons are reported as having contracted the plague, of which number twenty-eight are already dead. It will be seen from this that the disease must be of a very virulent type. The excitement among the people is said to be intense and uncontrollable. The scenes which were enacted in Spain during the epidemic which ravaged that country are being repeated in Croatia. The physicians are being stoned, and wives and children deserted. The superstition of these people is so great that almost any form of barbarity may be expected. The matter begins to have a serious aspect for central Europe, when cholera in a virulent form has obtained so firm a foothold in Austria; and, if the disease continues to spread, something like a panic may be anticipated. If the report of the appearance of cholera at Pesth is confirmed, the danger is greatly increased, as the onward march of this epidemic disease is greatly favored, when it reaches cities situated upon rivers which are great highways of travel.

THE FEVER which broke out in Biloxi, Harrison county, Miss., in August last, has occasioned great excitement and alarm throughout the length and breadth of the Mississippi valley. The opinion was expressed by us at that time, that it was undoubtedly yellow-fever. This was based upon our knowledge of the skill and experience of Dr. Joseph Holt, president of the Louisiana state board of health, who declared the disease to be of that nature. This opinion has been controverted by the physicians of Biloxi, which is not a matter of surprise, and also, as appears in the daily press, by the physicians of the U. S. marine hospital service. We have just received from Dr. Holt a detailed account of the outbreak and its subsequent history, and are more convinced than ever that the citizens of Biloxi have had true yellow jack in their midst, and that, if the disease is now under control, that result has been attained by the vigorous action of the Louisiana board in

instituting a quarantine against the infected city. Had this not been done, the existence of the fever would probably have been concealed until it had obtained such a hold that months rather than weeks would have elapsed before it was conquered. It is a sad commentary on human nature, that not only the people, but even medical men and officials, will attempt to delude themselves into the belief that a pestiferous disease does not exist in their midst, simply to avoid the risks to reputation and commerce which a knowledge of the true state of things would create, when they must know, from an experience which has been repeated over and over again in the past, that concealment or suppression can at best avail nothing, and that such a policy can but result in a wide-spread and probably uncontrollable epidemic, which will cause untold suffering and misery, and increase the mortality a hundred-fold.

THE BRITISH ASSOCIATION FOR THE ADVANCEMENT OF SCIENCE.

THE British association meeting is now drawing to a close, and may be said to have been very successful in all respects, but without any great sensation. About twenty-five hundred tickets have been taken for it, and the local arrangements were most complete. A special feature in them is a large exhibition of the manufactured products of this so-called workshop of the world.' Great care has been exercised in the selection of the exhibits, which must have been produced within a radius of fifteen miles from the centre of the town, and they illustrate in a remarkable degree the applications of science and art to manufacturing processes. A very large number of firms have also thrown open their works to the inspection of visitors. An unusual number of colonial and American visitors are attending the meeting, among the latter of whom Professor Barker and Prof. Carvill Lewis, both of Philadelphia, are prominent figures. The president, Sir W. Dawson of Montreal, opened the meeting with an address upon "The geology of the Atlantic Ocean and the land on its borders," which, together with the addresses of Prof. G. H. Darwin, president of the section of mathematics and physics, and of Mr. Crookes, president of the chemical section, will be found in full in Nature for Sept. 2. The subject of the former was " The value of the unit of geological time, from the point of view of cosmical physics." Mr. Crookes dwelt, in somewhat hypothetical fashion, it is true, with the genesis of the chemical elements, and he suggested a process for their evolution by the gradual cool

ing of primordial matter termed 'protyle' (analogous to protoplasm), which contained within itself the potentiality of all possible atomic weights. The keynote of the presidential address by Professor Bonney to the geological section was contained in the phrase, "the application of microscopic analysis to discovering the physical geography of bygone ages." In the biological section Mr. Carruthers, the president, drew attention to the past history of those species of plants which still form a portion of the existing flora. Sir F. Goldsmid, who presides over the geographical section, took for his subject "The means of popularizing the study of geography," a contribution to which end is seen in an exhibition of appliances therefor, open during the meeting. In the section of economic science and statistics, Mr. J. Biddulph Martin, in his presidential address, gave an exposition of the claims of this subject to a scientific status. In that of mechanical science, the president, Sir James N. Douglas, dealt with the peculiarly appropriate subject of lighthouses, since probably the largest manufactories of lighthouse apparatus in the world are to be found in Birmingham. Lastly, in the anthropological section, Sir George Campbell recommended from the presidential chair the systematic and scientific cultivation of man with a view to both physical and mental qualities, homi-culture,' in the same sense as oyster-culture, bee-culture, etc.

Turning to the general work of the meeting, it may be remarked that there were, at its commencement, between six hundred and seven hundred papers to be read and discussed in these various sections. Geology seems the most prolific, that section being almost overburdened with work. Two subjects for special discussion were selected some months ago: 1°, The theory of colorvision; 2°, The nature of solution.' The latter was confined to the chemical section, but the former was conducted at a joint meeting of the physical and biological; and it was remarked at the outset that on no previous occasion had two sections held a joint discussion. The result was so successful, that it is hoped this precedent may be followed. No formal papers were read, but the subject was opened by Lord Rayleigh, who, in a speech of some length, reviewed the theory from the physical point of view. Colors might differ in three ways, brightness, freedom from dilution with white, and hue: hence, from any four colors and black, a match might be made. He insisted very strongly on the distinction in effect between mixing colors (or paints) and mixing lights. No other known colors than red, violet, and green were 'primary,' though it was possible that some other unknown tints might be the real primary

colors. In the so-called color-blindness, colorvision was usually twofold, or dichroic.

All that

he said, however, involved the assumption (probably true) that a mixture is more complicated than its ingredients. Dr. König of Berlin followed with an account of a large series of very careful experiments upon elementary sensations of color, - an analysis of color-sensations without any hypothesis, which led him to the conclusion that the views of Thomas Young as to color, viewed in the light of modern experimental research, were certainly true. Dr. Michael Foster, speaking from the physiological point of view, pointed out to the physicists the difficulty of applying their theories of color, and expounded Hering's theory, according to which colors might be divided into pairs, one of which produced assimilation in the substance of the retina, and the other dissimilation, such as blue and yellow, red and green, and so on. Mr. J. Tennant pointed out that both Hering's and Young's theories had three independent variables, and led to the same general results. As, however, Hering's unquestionably explained the phenomena of simultaneous contrast best, he preferred it on that ground. The discussion came to a premature end, from lapse of time. That upon the nature of solution was opened by Dr. Tilden, who had studied the subject mainly from the point of view of the thermal phenomena occurring at solution. He presented an able summary of our knowledge of the subject, and showed that the solubility of a salt depended mainly on its melting-point, as well as on similarity of constitution between it and the solvent. Dr. Nicol showed experimentally that the molecules of a salt stood in the same relation to all the molecules of the water in which it was dissolved, or, in other words, that salts did not retain their water of crystallization in solution. Dr. Armstrong, Mr. Hartley, and Dr. Gladstone, however, differed from this view, considering that the hypothesis of residual affinity,' broached by Helmholtz, afforded a sufficient explanation of observed facts.

At one of the general evening meetings, Professor Rucker delivered a brilliant lecture to a very large audience, upon Soap bubbles.' The experimental illustrations, all of which were projected on a screen by the electric light, were of exceeding beauty and invariably successful. The particular point brought before the audience was the thickness and other properties of the black film of the bubble. The unit of measurement employed was the millionth of a millimetre. It was shown that this thickness varied considerably, but that the optical and electrical methods of measurements agreed closely in any particular