Popular Science Monthly/Volume 5/May 1874/Literary Notices
As this work was announced to appear in the "International Scientific Series," and has been withdrawn from it, a word of explanation is here desirable. In drawing up the plan of this series, it was decided that one of the books now most called for is a compendious treatise upon the science of man, based upon the intimate interactions of body and mind, or what may be termed Mental Physiology. While Prof. Bain took up the theories of their relation as a philosophical question, there was wanted a practical exposition of the science of Human Nature, such as might become a text-book of guidance and education in the general conduct of life. Dr. Carpenter, whose numerous and well-known physiological works covered this ground more perfectly than those of any other author, was applied to as the most competent man to prepare the work required. When solicited to undertake it, although much occupied with his active duties as Registrar of the London University, and absorbed in a course of special scientific inquiries, he cordially consented, and at once entered upon the labor. But it soon became apparent that the subject was too large to be compressed within the limits which were thought advisable for such a series, and, rather than impair the value of so important a work, it was found best to take it from the list and issue it separately. It conforms, however, to the popular style of these works, and is well adapted for general reading.
Dr. Carpenter's work is neither a technical treatise upon physiology nor a manual of scientific psychology, but it is an elaborate exposition of those relations of body and mind which must form a foundation of any true science of human nature. Physiology is generally considered as a science that belongs to the doctors, and of which it is necessary for everybody to know something for hygienic reasons. But the study of man, for general practical purposes, has hitherto been held to consist in the study of mind, while that has been considered from the metaphysical point of view, the body being thrown out of the account. This has been the powerful tendency of the past, and it is still so influential that books upon the so-called science of man are still frequently issued which are limited to one portion of his nature, and that, too, studied by a false method and out of all its actual relations. This disruption of man and the contemptuous dismissal of one part of his being as his "lower nature," while the other is magnified and dealt with apart, has been formerly defended on religious grounds; and the attempt to bring his whole nature into view and to consider it in its wonderful unity has been resisted as involving "materialism." This view is, however, latterly giving way, and it is more and more recognized that man must be studied in the totality and living harmony of his nature. Dr. Carpenter quotes the impressive words of Charles Buxton in his "Notes of Thought," as indicating the point of view that must now be taken in relation to this subject. Mr. Buxton says: "Irresistible, undeniable facts demonstrate that man is not a den wherein two enemies are chained together, but one being—that soul and body are one—one and indivisible. We had better face this great fact. 'Tis no good to blink it. Our knowledge of physiology has come to a point where the old idea of man's constitution must be thrown aside. To struggle against the overwhelming force of science under the notion of shielding religion is mere folly."
Dr. Carpenter adds: "These well-considered conclusions of a deeply religious mind may be specially commended to the consideration of those who are disposed to condemn without examination any thing that savors of 'materialism' which they have been accustomed to regard as philosophically absurd and morally detestable. And those who assume that physiological psychology strikes at the root of morals and religion may be fearlessly asked to show in what a system which leaves the will of man free to make the best use he can of the intellectual and moral capacities with which his bodily organism has been endowed by his Creator, and which gives him the strongest and noblest motives, both for self-discipline and for philanthropic exertion, is unworthy of the nature and destiny of the being whose creation in the 'image of God' can have no higher meaning than his capacity for infinite progress."
The difference between the new point of view and the old is not a mere speculative difference, or a matter of abstract belief. The study of man as an actual whole, a complex working phenomenon, and a fact of experience, has given us a kind of knowledge that is invaluable for the uses of all in every-day life. This kind of knowledge, concerning human nature, has been long and slowly accumulating, as the result of modem observation, though it has recently become more extended and accurate in many particulars, and Dr. Carpenter's work, we may say, has first presented it with the systematic fullness which its importance demands.
In his plan of treatment, Dr. Carpenter classifies from the mental side; that is, it is mental phenomena and problems that are successively taken up. After a preliminary statement of the general relations between mind and body, in the first chapter, he takes up the structure and modes of action of the nervous apparatus in the second chapter, and then proceeds to consider in successive chapters the subjects of Attention, Sensation, Perception, and Instinct, the Emotions, the Will, Memory, Common-sense, Unconscious Cerebration, Reverie, Sleep, Dreaming, Somnambulism, Electro-biology, Mesmerism, and Spiritualism, Intoxication and Delirium. But each and all of these manifestations are considered, not in themselves merely, but as conditioned by the physiological constitution. Whatever may be their ultimate nature, practically they are effects of a vital mechanism by the laws of which they are determined. Much of this wonderful connection is of course, as yet, far from being understood. We are indebted to Dr. Carpenter for having shown that a great deal more is understood of the psychical and vital interactions than has become generally known. Dr. Carpenter has won his reputation as a physiologist, largely from the clearness of his expositions, and the present work shows that his capacity in this respect is still vigorous. Its most scientific parts are attractive reading, and the extensive array of personal instances and incidents, which illustrate his positions, gives great fascination to the volume. It is a book hard to lay down when once entered upon, and Dr. Carpenter may be congratulated upon having contributed so fresh and adequate a book upon such an important subject.
This able treatise is entitled to be classed at once with such valuable and solid works as Mill's "Logic," Whewell's "History of the Inductive Sciences," and Herbert Spencer's "First Principles." Whether it be equal to either of those treatises, as a contribution to scientific knowledge, we shall not assume to say, but it is certainly a timely and powerful exposition of scientific method, in the light of the later advances of knowledge. The author sets out with the assumption, which few will question, that the rapid progress of the physical sciences during the last three centuries has not been accompanied by a corresponding advance in the theory of reasoning. Physicists are usually too much engrossed in the immense and ever-accumulating details of their special sciences to give sufficient attention to the methods of reasoning which they unconsciously employ. It becomes necessary, then, that certain minds should devote themselves absorbingly to this neglected side of science, for few will deny that the clearing up of questions of order, logic, and method, are indispensable to its rational progress. To do any justice to this work, by a notice or review of it within such space as we can allow, would be impossible, and the best course is to let the author speak for himself in regard to the aims and characteristics of his undertaking. The following passages are from his preface:
"The study both of Formal Logic and of the Theory of Probabilities has led me to adopt the opinion that there is no such thing as a distinct method of induction as contrasted with deduction, but that induction is simply an inverse employment of deduction. Within the last century a reaction has been setting in against the purely empirical procedure of Francis Bacon, and physicists have learned to advocate the use of hypotheses. I take the extreme view of holding that Francis Bacon, although he correctly insisted upon constant reference to experience, had no correct notions as to the logical method by which, from particular facts, we educe laws of Nature. I endeavor to show that hypothetical anticipation of Nature is an essential part of inductive inquiry, and that it is the Newtonian method of deductive reasoning, combined with elaborate experimental verification, which has led to all the great triumphs of scientific research.
"In attempting to give an explanation of this view of scientific method, I have first to show that the sciences of number and quantity repose upon and spring from the simpler and more general science of logic. The theory of probability, which enables us to estimate and calculate quantities of knowledge, is then described, and especial attention is drawn to the inverse method of probabilities, which involves, as I conceive, the true principle of inductive procedure. No inductive conclusions are more than probable, and I adopt the opinion that the theory of probability is an essential part of logical method, so that the logical value of every inductive result must be determined consciously or unconsciously, according to the principles of the inverse method of probability.
"The phenomena of Nature are commonly manifested in quantities of time, space, force, energy, etc.; and the observation, measurement, and analysis of the various quantitative conditions or results involved, even in a simple experiment, demand much employment of systematic procedure. I devote a book, therefore, to a simple and general description of the devices by which exact measurement is effected, errors eliminated, a probable mean result obtained, and the probable error of that mean ascertained. I then proceed to the principal, and probably the most interesting, subject of the book, illustrating successively the conditions and precautions requisite for accurate observation, for successful experiment, and for the sure detection of the quantitative laws of Nature. As it is impossible to comprehend aright the value of quantitative laws without constantly bearing in mind the degree of quantitative approximation to the truth probably attained, I have devoted a special chapter to the theory of approximation, and, however imperfectly I may have treated this subject, I must look upon it as a very essential part of a work on scientific method.
"It then remains to illustrate the sound use of hypothesis, to distinguish between the portions of knowledge which we owe to empirical observation, to accidental discovery, or to scientific prediction. Interesting questions arise concerning the accordance of quantitative theories and experiments, and I point out how the successive verification of an hypothesis by distinct methods of experiment yields conclusions approximating to but never attaining certainty. Additional illustrations of the general procedure of inductive investigations are given in a chapter on the 'Character of the Experimentalist,' in which I endeavor to show, moreover, that the inverse use of deduction was really the logical method of such great masters of experimental inquiry as Newton, Huyghens, and Faraday.
"The application of scientific method cannot be restricted to the sphere of lifeless objects. We must sooner or later have strict sciences of those Mental and Social phenomena which, if comparison be possible, are of more interest to us than purely material phenomena. But it is the proper course of reasoning to proceed from the known to the unknown—from the evident to the obscure—from the material and palpable to the subtile and refined. The physical sciences may therefore be properly made the practice-ground of the reasoning powers, because they furnish us with a great body of precise and successful investigations."
It is thus evident that the plan of Prof. Jevons's work involves a thorough handling of the most recent questions that have been raised in science and philosophy, and an examination of it will show that he has carried out his project in an able and independent manner. We publish a portion of his last chapter, showing his liberality of view. It is to be hoped that the publishers will find it for their interest to modify the price of this work, so as to bring it within reach of a large circle of those who, in our opinion, would be glad to have it.
The object of this work is to call public attention to certain practices in the existing system of life insurance, entailing loss and injury upon the policy-holder. Chief among these practices is the treatment of holders who allow their policies to lapse by non-payment of the premium, or surrender them from a desire to change the investment. In either case it is usual for the company to issue a "paid-up policy," that is, a guarantee to pay a fraction of the original policy at the expiration of its tenn, or to pay the resigning policy-holder a small sum of money as the "surrender value" of the policy. Mr. Wright assumes, and it must be confessed with great show of reason, that the "surrender value," in all cases where the policy has existed beyond three years, and in some cases beyond one year, is far less than the amount the policy-holder is justly entitled to receive. According to his idea, legitimate life insurance is a compound of insurance proper with the savings-bank business, and his system is therefore termed Savings-Bank Life Insurance. From this point of view all premiums paid are resolvable into two parts. One part pays the cost of insurance, that is, the expenses of the company: the other is merely a deposit, in trust with the company, for gradual accumulation to equal the sum of the policy by the time that that shall become due. Either part may be larger or smaller, according to the nature of the policy. With "ordinary life" policies, the premiums are small, and distributed over a great number of years; there is, therefore, great risk that the company will have to pay the policy before the accumulated deposits can yield a sum to equal it. To compensate it for this great risk, the company is justified in taking for itself the largest part of the premium. But, in the case of an endowment policy of short term, the premium being large and confined within a few years, the deposit accumulates very rapidly, and will soon equal the policy. There being, therefore, much less risk than in the former case, the company can be justified in taking only a small part of the premium for its own use. Thus it is plain that the company's share of the premium is largest in the case of an ordinary life policy, and smallest in that of a short-term endowment policy. It is called the "insurance value," and is appropriated to the payment of the expenses of the company. The policyholder's share of the premium is smallest with the first kind of policy and largest with the last; it is called the "reserve," and should never be touched for any other purpose than the payment of the policy to which it belongs. Mr. Wright contends that the policy-holder should be at liberty to return his policy at any time, and withdraw the "reserve" unimpaired, save in a small sum to compensate the company for the loss of a good risk. In some cases the policy-holder is entitled to recover more than the "reserve" when he surrenders his policy. This occurs with "single-premium policies"—policies on which many future small premiums are anticipated, or commuted by the payment of a single large premium. This single large premium, like the small annual premiums considered above, resolves into two parts, the "insurance value" and the "reserve." The "reserve" is the same in nature as with the annual premium, though of course much larger; but a new element enters into the composition of the "insurance value." The "insurance value" of an annual premium compensates the company for its risk in one year, while the "insurance value" of a "single premium" compensates the company for its risk during all the years that the policy has to run. Now, if the holder of a "single-premium policy," having twenty or more years to run, becomes desirous to surrender his policy at the end of five years, he should get back from the company, not only the "reserve," but also that portion of the "insurance value" that has been set apart by the company to compensate for the risk attached to the remaining fifteen or more years of the policy's term. Clearly, if the company retains more of the "insurance value" than will compensate it for bearing the risk during the five years that have expired, it will exact pay for work that it has not performed, and its proceeding cannot be justified on any ground of equity. The company is, of course, entitled to some compensation for the loss of its interest in the "insurance value" that it would have earned had the policy remained in force; but it is idle, as well as in equitable, to contend that the compensation should equal the "insurance value." It seems to us that the present value of the unearned "insurance value" would be the just compensation. Mr. Wright, however, argues that it should be only enough to enable the company to procure as good a risk as the one it has lost by the surrender of the policy, and that eight per cent. of the unearned "insurance value" would be sufficient for this purpose; that is, eight per cent. would yield an amount equal to the commission usually paid to an agent to obtain a risk. Mr. Wright, it is seen, holds that loss of the risk is that for which the company should be compensated, but to us it seems to be, as above expressed, loss of interest in the "insurance value" which would have been paid to it had the policy remained in force. This "insurance value" on the company's share of the premiums is supposed to compensate the company for the risk of undertaking to carry the policy, and is clearly the only interest that the company has in the transaction. The compensation that the company receives in case of surrender is called the "insurance charge." As it is based on the "insurance value" it varies proportionately, and is therefore largest on "ordinary life policies" and smallest on "short-term endowments," and on the latter class of policies it decreases as the age of the policy increases. To recapitulate, Mr. Wright contends that life insurance is compounded of insurance proper and the business of the savings-bank; that the premiums consist of two parts, the "insurance value," which belongs to the company when earned, and the "reserve," which belongs to the policyholder, having been merely deposited with the company for accumulation, to be withdrawn whenever it suits him to return his policy; that the company for its interest in the risk is entitled to make a "surrender charge" when the policy is returned; and that this "surrender charge" should be based on the "insurance value," but should constitute only a very small part of it. This is, without doubt, a just conception of the nature of life insurance; but, while the companies agree with Mr. Wright in dividing the premiums into "insurance value" and "reserve," they disagree with him as to the ownership of the "reserve," half of which they insist on retaining for themselves, in case of surrender. The Mutual Life, of New York, retains from fifty to seventy-five per cent, of the "reserve," in settling for surrendered policies, and the Equitable from fifty to sixty per cent., and this is done on all policies alike, without respect to age or class. Having just seen that the "surrender value," usually constituting the difference between the "reserve" and a moderate "surrender charge," and sometimes exceeding the "reserve," varies in amount with the class of the policy, and far more so with its age, the reader is competent to decide for himself whether the company's uniform practice of retaining from fifty to seventy-five per cent, of the "reserve" on all policies is or is not equitable. For our part we think, with Mr. Wright, that it is not.
Mr, Wright further contends that both the "surrender charge" and the "surrender value," at any period of the policy's existence, should be ascertained sums, and known to the policy-holder before he insures, so that he can understand all the terms of the contract he is making. For this purpose he has prepared, and inserted in the book, several specimen-tables showing the "insurance value," the "reserve," the "surrender charge," and the "surrender value" of various classes of policies at the time of issue and in each year thereafter. This is precisely what the companies claim cannot be done. They say that the "surrender value" at any future time cannot be calculated, because it is impossible to foretell what the dividends or surplus above working cost will be. But, throwing dividends out of the question as an unessential factor, the thing becomes easy enough. For instance, no company will deny that the "reserve" at any period of the policy's existence can be easily ascertained. But the "reserve" is made up of one part of the premiums, and, if this part can be ascertained, why cannot the "insurance value," which is made up of the other part of the premiums, be also ascertained? It is unnecessary to know any other factors than these, to be able to determine the amount of the "surrender value." The latter factor forms the basis of the "surrender charge," which may be eight per cent, of it, and the "surrender charge" deducted from the former leaves the "surrender value."
We have thus endeavored to give a brief outline of the main feature of Mr. Wright's book; the others are chiefly incidental to the illustration of this one. The glimpses occasionally given of the manner in which matters are conducted beneath the surface of life insurance are not calculated to leave on the reader's mind a favorable impression of at least one or two of the actors. In this connection, however, the tone of the writer is not always as dignified as it might be. The chapter at the end of the book, on the relation between currency and life insurance, exhibits some sound financial views. The book aims a vigorous blow in defense of the people, and it is to be hoped that its effect will be decisive.
The avidity of the general public for information in regard to recent researches in physics, and particularly in regard to researches made by aid of the spectroscope, is witnessed by the number of volumes which have appeared within the past few years devoted solely to the popular exposition of these subjects. The announcement of a new book with the same purpose is one which, we should fancy, the average reader of these books would receive with mingled feelings. It seems to us that this average reader, while feeling that it was his duty to rejoice that the class which he represents was being so very fully supplied with treatises on a certain class of topics, would likewise begin to doubt whether the topics themselves had not been exhausted.
At least, he might doubt whether the popular exposition of them had not been carried to an extreme point. Certainly it seems very hard to add to the books of Roscoe and Schellen any thing in regard to the fundamentals of Spectrum Analysis, which shall be worth adding. It is easy to conceive our average reader turning the pages of a new book of this sort with a kind of nervous fear, lest he should come across those tiresome wood-cuts of a German-looking man gazing intently into a prism in the hope of seeing a candle-flame double, or of two sombre individuals shut up in a dark and very large room, alone with Newton's experiment. These woodcuts he has seen for years, and they seem to him as the brown-stone houses on the Fifth Avenue seem to the weary traveler; mile-stones that he can never pass—"a procession which never gets past its given point."
Now, we distinctly sympathize with our average reader, and we claim that a book of this nature, to be necessary or even acceptable at this time, must be a decided step in advance of the former ones.
The volume before us contains 676 pages (including a good Index), and it is divided into two parts: Part I. is devoted to a popular account of ancient and modern Sun-work; Part II. contains communications made by the author to the Royal Society of London, and to the French Academy of Sciences. Added to these we have sixteen valuable Notes on various special points; and two Appendices, one giving the "Instructions to Observers of the Eclipse of 1871," and the other being Respighi's "Memoir on Solar Prominences."
To consider the volume in inverse order, we may say that, of Part II., the valuable Notes and Appendices are the only parts which ought to have been given in their present form, according to our judgment, and it may even be doubted whether the Notes should not have been worked into the text. Mr. Lockyer says, in regard to the contributions to the Royal Society and to the Academy of Sciences, that they are "of course" given verbatim. Here the author has, it seems to us, forgotten the proper object of his book. These papers were written from time to time as results began to come from the "new method," and they are of necessity incomplete. The only object in giving them in their original form is to show exactly Mr. Lockyer's relation to the progress of discovery and research. But the history of the subject is very well known among all interested in it, and Mr. Lockyer's foremost place in certain branches of it is too well established to need a repetition of the formal proofs.
To the scientific worker these papers are already accessible in the original, and, for general purposes, they should have been entirely recast, as they are decidedly not in the best form now.
With regard to the first part of the work we may say that much of it is a repetition of matter which has been thoroughly treated in other books. Some of it consists of accounts of eclipse-work which the author himself did, and the story of this is told in a thoroughly good and interesting way. Mr. Lockyer's accounts of the work of others are eminently fair, and exhibit good feeling and entire appreciation. The chapter on Mr. Carrington's researches on solar spots is an example, and the author's account of the discovery of the new method of viewing prominences which was applied by Janssen and himself, though first conceived by Lockyer, is thoroughly admirable for fairness and candor.
Part I., however, has more serious defects than the final section of the book. It is entirely deficient in judicious arrangement, and its perusal can only confuse the ideas of the learner. It is, in fact, a reprint of essays (each of them good in itself and in its place), which Mr. Lockyer, sometimes alone, sometimes in concert with Mr. Balfour Stewart, contributed to English periodicals, and of occasional lectures.
It abounds in repetitions; sometimes whole paragraphs, almost pages, are printed at least twice, and the whole seems to show a desire, to speak plainly, to "make a book."
We must insist that, while it is, abstractly, a thing to be grateful for that Mr. Lockyer should give his valuable time to the popular exposition of scientific truths, some of which he has been so fortunate as to discover, it is, in the case before us, still a fact that he has added scarcely any thing to the ample information in regard to them which is now accessible, and nothing at all to his scientific reputation.
His character as a man seems to be shown, in his account of his relation to other scientific men—his friends—and that is almost the only outcome of this expensive volume, whose principal fault is a want of a sufficient raison d'être.
The reader of this book is long puzzled to discover the fitness of the title to the matter presented for his consideration, nor can he, until, near the end, the author's view is revealed to him, that each generation of mankind, from the conditions of its existence, is subjected to physical persecution—or martyrdom—that the condition of the succeeding generation may be improved. The current theology is repudiated, and with it the idea of the individual existence of the human soul after death. The idea of a God, impersonal, indefinable, and unknowable, is, however, retained and strongly enforced; and with it there seems to be connected in the author's mind, though it is not clearly expressed, an idea that the human soul is immortal in the sense of being a materially embodied part of the great animating power of the universe, into which it lapses—losing its individuality—after the death of the body. To expound these views is really the aim of the book, although it ostensibly purports to be a kind of universal history of human progress, written to show the influence of Africa upon civilization. It is divided into four chapters. The first presents a panoramic portrayal of the ancient civilizations of Egypt and the north of Africa, Asia Minor, Greece, Rome, their rise, maturity, and decay, and the influence they exercised upon each other. The second chapter deals, after the same manner, with mythology, Judaism, Christianity, Mohammedanism. The third traces the progress of Liberty, giving a comparatively extended account of the origin of the slave-trade and the antislavery movement, and their influence upon American affairs. The last chapter sketches the rise and progress of intellect, and pictures its probable future. The theories of evolution and natural selection form the ground-work of the plan. The author acknowledges his indebtedness to others for his facts, but is entitled to some credit for originality in the conception and arrangement of the work. The style is vigorous, and entices the reader into more than a cursory perusal.
This book comprises a series of six lectures, delivered in 1862, before the Brooklyn Institute, and first published in 1865, but now reissued, the former editions having passed out of print. The lectures were delivered for the purpose of showing that there is "order in Nature; that the animal kingdom, especially, has been constructed upon a plan which presupposes the existence of an intelligent being as its author," and the "scientific grounds of the working of a Providence in the world." In the last respect, the view advanced is that the present diversity of animal life, or species, has not resulted from the influence of outward circumstances upon a few primarily simple forms, but from the direct and continually-repeated workings of a Divine Will or Providence; in other words, that the diversity has resulted from Divine creations. The arguments adduced to prove this part of the theory are grounded upon the fact that geologic revelations show certain low forms of animal life to have existed in former periods, in greater diversity than at present. The first lecture presents the plan of the animal kingdom as exhibited in its four great divisions; the second presents the relative standing of each division to the other, and of the various members of each division; the third proves the antiquity of animal life by the existence of coral-reefs; the fourth gives an outline of the geological history of the earth. The remaining two lectures are devoted to proving the theory of an intervening Providence. The book is full of interesting facts, and eminently adapted to the theology of the day.
A well-executed book, upon the subject here designated, would be very valuable: the present one seems to be not up to the requirement. Upon a class of questions which, of all others at present agitating the scientific world, are the freshest and the newest, this is an old book. It was prepared for publication seven years ago, and was not even then up to the times. An example of the antiquated and unreliable character of the work is afforded by the author's treatment of the most eminent thinker of the tune on problems of social science. Mr. Herbert Spencer is judged as a sociologist by his views developed in "Social Statics;" how fairly will appear from the fact that "Social Statics" was Mr. Spencer's first work, published twenty-four years ago. And not only this, but he was himself so dissatisfied with it that he would not consent to its republication in this country, without incorporating a preface which indicated that his views had undergone important modification. It was, in fact, from the incompleteness of the basis of this discussion for a true sociological science that Mr. Spencer was led to devote himself for twenty years to the development of a system in which the foundations of sociology should be more deeply and securely laid in the sciences of life and mind, and the laws of Nature, in their latest and highest interpretations.
Mr. Hamilton's book ranges wide over the field of social philosophy, and discusses the views of many men in relation to it, but, with much information, there is a vague speculation, and more of criticism than history. Of social science, as a simple generalization of social phenomena, or a body of principles based upon facts of observation, like other sciences, he seems to have but an obscure conception, as is evinced by the fol lowing statement of the problems of social philosophy: "What are the causes or laws which determine the social destiny of the individual, which determine in the long-run, and in the absence of extraordinary disturbing causes, whether he shall be prosperous or the contrary; whether he shall be a pauper or millionaire; a laborer or capitalist; a peasant or prince—which determine, in short, whether his own internal momentum or centrifugal force shall be overpowered by the potent gravitation, or centripetal force, which is constantly prostrating human efforts, or shall enable him to maintain an independent position, and revolve in an orbit of his own."
The author states that the peculiarities of Government surveying being unexplained by existing works on land-surveying, new contractors with the Government are often embarrassed by the want of information on the subject. To meet this want, the treatise was prepared. The principles of surveying, the application of astronomy, and the uses of instruments and of logarithmic tables, are expounded briefly but intelligibly. Suggestions are also made for procuring a surveying outfit, and for rendering the alkaline waters of the Western Plains fit for drinking. Tables of convergences, logarithms, etc., are given at the end. The book is bound in morocco for pocket-use.
This is an embodiment in book-form of a series of essays previously published in the Cornhill Magazine. The title forcibly indicates the nature of the subjects discussed, these being generally beyond the pale of exact science, yet possessing in some degree a scientific character. However, with regard to the last three essays, "Gambling," "Coincidences," and "Ghosts," it is difficult to recognize their claim to a position under the title, except in the effort of the author to combat, after an analytical or scientific method, the errors prevailing on those subjects. The essay on "The Herschels and the Star-Depths" sketches the observations of those great astronomers on the "dark portions" of the heavens, and their resulting discoveries of nebulæ. "A Voyage to the Sun," and "A Voyage to the Ringed Planet," in the assumed and fanciful form of a journey to those luminaries, describe their features and the peculiar theories relating to each. "Life in Mars" discusses the reasons for believing that some kind of animal life exists upon that planet, and "A Whewellite Essay on Mars" gives the reasons for doubting that that life resembles such as we see upon our own. Besides several other essays on astronomical subjects is one on "Earthquakes," another on "Coal," and still another on "Flying and Flying-Machines." The clear and vigorous style and varied character of its contents make the book highly interesting. It is to be regretted that it was not published in a cheaper edition.
Of suitable size, this book is intended as a pocket manual for students of electricity, as well as a reference-book for experienced electricians. It explains, at the beginning, the laws upon which galvanometric measurements are based, next the galvanometer itself, and lastly the uses of the instrument. It is illustrated throughout. To the end are appended useful tables of the wires and tangents, and of the weights and resistances of iron and copper wires.