The work treats of the unity, origin, antiquity, and original localization of the human species, peopling of the globe, acclimatization, primitive man, formation of the human races, fossil human races, present human races, and the physical and psychological characters of mankind.

“In this interesting book Professor Rood, who, as a distinguished Professor of Physics in Columbia College, United States, must be accepted as a competent authority on the branch of science of which he treats, deals briefly and succinctly with what may be termed the scientific rationale of his subject. But the chief value of his work is to be attributed to the fact that he is himself an accomplished artist as well as an authoritative expounder of science.”—Edinburgh Review, October, 1879, in an article on “The Philosophy of Color.”

“This work must be pronounced the most remarkable discussion of educational problems which has been published in our day. We do not hesitate to bespeak for it the widest circulation and the most earnest attention. It should be in the hands of every school-teacher and friend of education throughout the land.”—New York Sun.

“Professor Thurston almost exhausts his subject; details of mechanism are followed by interesting biographies of the more important inventors. If, as is contended, the steam-engine is the most important physical agent in civilizing the world, its history is a desideratum, and the readers of the present work will agree that it could have a no more amusing and intelligent historian than our author.”—Boston Gazette.

“The study of spectrum analysis is one fraught with a peculiar fascination, and some of the author’s experiments are exceedingly picturesque in their results. They are so lucidly described, too, that the reader keeps on, from page to page, never flagging in interest in the matter before him, nor putting down the book until the last page is reached.”—New York Evening Express.

“The attempt at a connected account of the general physiology of muscles and nerves is, as far as I know, the first of its kind. The general data for this branch of science have been gained only within the past thirty years.”—Extract from Preface.

“It is pleasant to find an American book which can rank with the very best of foreign works on this subject. Professor Le Conte has long been known as an original investigator in this department; all that he gives us is treated with a master-hand.”—The Nation.

“This is in many respects one of the most interesting contributions to zoÖlogical literature which has appeared for some time.”—Nature.

“There was need for a book like this, which discusses the atomic theory both in its historic evolution and in its present form. And perhaps no man of this age could have been selected so able to perform the task in a masterly way as the illustrious French chemist, Adolph Wurtz. It is impossible to convey to the reader, in a notice like this, any adequate idea of the scope, lucid instructiveness, and scientific interest of Professor Wurtz’s book. The modern problems of chemistry, which are commonly so obscure from imperfect exposition, are here made wonderfully clear and attractive.”—The Popular Science Monthly.

“Whoever will follow these pages, crayfish in hand, and will try to verify for himself the statements which they contain, will find himself brought face to face, with all the great zoÖlogical questions which excite so lively an interest at the present day.”

“The reader of this valuable monograph will lay it down with a feeling of wonder at the amount and variety of matter which has been got out of so seemingly slight and unpretending a subject.”—Saturday Review.

“Suicide” is a scientific inquiry, on the basis of the statistical method, into the laws of suicidal phenomena. Dealing with the subject as a branch of social science, it considers the increase of suicide in different countries, and the comparison of nations, races, and periods in its manifestation. The influences of age, sex, constitution, climate, season, occupation, religion, prevailing ideas, the elements of character, and the tendencies of civilization, are comprehensively analyzed in their bearing upon the propensity to self-destruction. Professor Morselli is an eminent European authority on this subject. It is accompanied by colored maps illustrating pictorially the results of statistical inquiries.

“In no field has modern research been more fruitful than in that of which Professor Judd gives a popular account in the present volume. The great lines of dynamical, geological, and meteorological inquiry converge upon the grand problem of the interior constitution of the earth, and the vast influence of subterranean agencies.... His book is very far from being a mere dry description of volcanoes and their eruptions; it is rather a presentation of the terrestrial facts and laws with which volcanic phenomena are associated.”—Popular Science Monthly.

“The volume before us is one of the pleasantest science manuals we have read for some time.”—AthenÆum.

“Mr. Judd’s summary is so full and so concise that it is almost impossible to give a fair idea in a short review.”—Pall Mall Gazette.

“Professor Young is an authority on ‘The Sun,’ and writes from intimate knowledge. He has studied that great luminary all his life, invented and improved instruments for observing it, gone to all quarters of the world in search of the best places and opportunities to watch it, and has contributed important discoveries that have extended our knowledge of it.

“It would take a cyclopÆdia to represent all that has been done toward clearing up the solar mysteries. Professor Young has summarized the information, and presented it in a form completely available for general readers. There is no rhetoric in his book; he trusts the grandeur of his theme to kindle interest and impress the feelings. His statements are plain, direct, clear, and condensed, though ample enough for his purpose, and the substance of what is generally wanted will be found accurately given in his pages.”—Popular Science Monthly.

This volume takes a wide survey of the field of error, embracing in its view not only the illusions commonly regarded as of the nature of mental aberrations or hallucinations, but also other illusions arising from that capacity for error which belongs essentially to rational human nature. The author has endeavored to keep to a strictly scientific treatment—that is to say, the description and classification of acknowledged errors, and the exposition of them by a reference to their psychical and physical conditions.

“This is not a technical work, but one of wide popular interest, in the principles and results of which every one is concerned. The illusions of perception of the senses and of dreams are first considered, and then the author passes to the illusions of introspection, errors of insight, illusions of memory, and illusions of belief. The work is a noteworthy contribution to the original progress of thought, and may be relied upon as representing the present state of knowledge on the important subject to which it is devoted.”—Popular Science Monthly.

“No living physiologist is better entitled to speak with authority upon the structure and functions of the brain than Dr. Luys. His studies on the anatomy of the nervous system are acknowledged to be the fullest and most systematic ever undertaken. Dr. Luys supports his conclusions not only by his own anatomical researches, but also by many functional observations of various other physiologists, including of course Professor Ferrier’s now classical experiments.”—St. James’s Gazette.

“Dr. Luys, at the head of the great French Insane Asylum, is one of the most eminent and successful investigators of cerebral science now living; and he has given unquestionably the clearest and most interesting brief account yet made of the structure and operations of the brain. We have been fascinated by this volume more than by any other treatise we have yet seen on the machinery of sensibility and thought; and we have been instructed not only by much that is new, but by many sagacious practical hints such as it is well for everybody to understand.”—The Popular Science Monthly.

“Judge Stallo’s work is an inquiry into the validity of those mechanical conceptions of the universe which are now held as fundamental in physical science. He takes up the leading modern doctrines which are based upon this mechanical conception, such as the atomic constitution of matter, the kinetic theory of gases, the conservation of energy, the nebular hypothesis, and other views, to find how much stands upon solid empirical ground, and how much rests upon metaphysical speculation. Since the appearance of Dr. Draper’s ‘Religion and Science,’ no book has been published in the country calculated to make so deep an impression on thoughtful and educated readers as this volume.... The range and minuteness of the author’s learning, the acuteness of his reasoning, and the singular precision and clearness of his style, are qualities which very seldom have been jointly exhibited in a scientific treatise.”—New York Sun.

“Mr. Darwin’s little volume on the habits and instincts of earth-worms is no less marked than the earlier or more elaborate efforts of his genius by freshness of observation, unfailing power of interpreting and correlating facts, and logical vigor in generalizing upon them. The main purpose of the work is to point out the share which worms have taken in the formation of the layer of vegetable mould which covers the whole surface of the land in every moderately humid country. All lovers of nature will unite in thanking Mr. Darwin for the new and interesting light he has thrown upon a subject so long overlooked, yet so full of interest and instruction, as the structure and the labors of the earth-worm.”—Saturday Review.

“Respecting worms as among the most useful portions of animate nature, Dr. Darwin relates, in this remarkable book, their structure and habits, the part they have played in the burial of ancient buildings and the denudation of the land, in the disintegration of rocks, the preparation of soil for the growth of plants, and in the natural history of the world.”—Boston Advertiser.

“This volume contains the record of various experiments made with ants, bees, and wasps during the last ten years, with a view to test their mental condition and powers of sense. The principal point in which Sir John’s mode of experiment differs from those of Huber, Forel, McCook, and others, is that he has carefully watched and marked particular insects, and has had their nests under observation for long periods—one of his ants’ nests having been under constant inspection ever since 1874. His observations are made principally upon ants because they show more power and flexibility of mind; and the value of his studies is that they belong to the department of original research.”

“We have no hesitation in saying that the author has presented us with the most valuable series of observations on a special subject that has ever been produced, charmingly written, full of logical deductions, and, when we consider his multitudinous engagements, a remarkable illustration of economy of time. As a contribution to insect psychology, it will be long before this book finds a parallel.”—London AthenÆum.

“M. Ribot reduces diseases of memory to law, and his treatise is of extraordinary interest.”—Philadelphia Press.

“Not merely to scientific, but to all thinking men, this volume will prove intensely interesting.”—New York Observer.

“M. Ribot has bestowed the most painstaking attention upon his theme, and numerous examples of the conditions considered greatly increase the value and interest of the volume.”—Philadelphia North American.

“To the general reader the work is made entertaining by many illustrations connected with such names as LinnÆus, Newton, Sir Walter Scott, Horace Vernet, Gustave DorÉ, and many others.”—Harrisburg Telegraph.

“The whole subject is presented with a Frenchman’s vivacity of style.”—Providence Journal.

“It is not too much to say that in no single work have so many curious cases been brought together and interpreted in a scientific manner.”—Boston Evening Traveller.

“His book is ingenious; ... his theory of how science gradually differentiated from and conquered myth is extremely well wrought out, and is probably in essentials correct.”—Saturday Review.

“The book is a strong one, and far more interesting to the general reader than its title would indicate. The learning, the acuteness, the strong reasoning power, and the scientific spirit of the author, command admiration.”—New York Christian Advocate.

“An attempt made, with much ability and no small measure of success, to trace the origin and development of the myth. The author has pursued his inquiry with much patience and ingenuity, and has produced a very readable and luminous treatise.”—Philadelphia North American.

“It is a curious if not startling contribution both to psychology and to the early history of man’s development.”—New York World.

“The discussion of man’s origin and early history, by Professor De Quatrefages, formed one of the most useful volumes in the ‘International Scientific Series,’ and the same collection is now further enriched by a popular treatise on paleontology, by M. N. Joly, Professor in the University of Toulouse. The title of the book, ‘Man before Metals,’ indicates the limitations of the writer’s theme. His object is to bring together the numerous proofs, collected by modern research, of the great age of the human race, and to show us what man was, in respect of customs, industries, and moral or religious ideas, before the use of metals was known to him.”—New York Sun.

“An interesting, not to say fascinating volume.”—New York Churchman.

“My object in the work as a whole is twofold: First, I have thought it desirable that there should be something resembling a text-book of the facts of Comparative Psychology, to which men of science, and also metaphysicians, may turn whenever they have occasion to acquaint themselves with the particular level of intelligence to which this or that species of animal attains. My second and much more important object is that of considering the facts of animal intelligence in their relation to the theory of descent.”—From the Preface.

“Unless we are greatly mistaken, Mr. Romanes’s work will take its place as one of the most attractive volumes of the ‘International Scientific Series.’ Some persons may, indeed, be disposed to say that it is too attractive, that it feeds the popular taste for the curious and marvelous without supplying any commensurate discipline in exact scientific reflection; but the author has, we think, fully justified himself in his modest preface. The result is the appearance of a collection of facts which will be a real boon to the student of Comparative Psychology for this is the first attempt to present systematically well-assured observations on the mental life of animals.”—Saturday Review.

“The author believes himself, not without ample cause, to have completely bridged the supposed gap between instinct and reason by the authentic proofs here marshaled of remarkable intelligence in some of the higher animals. It is the seemingly conclusive evidence of reasoning; powers furnished by the adaptation of means to ends in cases which can not be explained on the theory of inherited aptitude or habit.”—New York Sun.

“To the political student and the practical statesman it ought to be of great value.”—New York Herald.

“The author traces the subject from Plato and Aristotle in Greece, and Cicero in Rome, to the modern schools in the English field, not slighting the teachings of the American Revolution or the lessons of the French Revolution of 1793. Forms of government, political terms, the relation of law, written and unwritten, to the subject, a codification from Justinian to Napoleon in France and Field in America, are treated as parts of the subject in hand. Necessarily the subjects of executive and legislative authority, police, liquor, and land laws are considered, and the question ever growing in importance in all countries, the relations of corporations to the state.”—New York Observer.

President Porter declares of this work that “there are few books within his knowledge which are better fitted to aid the student who wishes to acquaint himself with the course of modern speculation and scientific thinking, and to form an intelligent estimate of most of the current theories.”

“The author of this work, which, regarded merely as an accumulation of verified and classified facts, is a unique and precious contribution to the data of comparative psychology, claims that he entered on his inquiry without any theory to defend, support, or illustrate. We are bound to say that, while his general conclusions are boldly and continually avowed, his claim of fairness and caution is justified by his method of examining particular phenomena; that he seems willing at all times to renounce any impression or belief which is shown to be scientifically untenable.”—New York Sun.

“In this work—two volumes of over 500 pages—Dr. Lindsay marshals a proportionately large number of facts against those philosophers who maintain that the intelligence of man differs in kind and not simply in degree from that of the lower animals. It is one purpose of his book to show that the main differences between man and the lower animals exist rather in their physical than in their mental structure. In this way of thinking, all animals possess not the semblance of, but the true substance of mind and will.”—New York World.

“So far as we are aware there has been no treatise upon the subject of animal intelligence so broad in its foundations, so well considered, or so scientific in its methods of inquiry, as that which has been prepared by Dr. W. Lauder Lindsay in two large volumes, the first being devoted to a study of animal mind in health, and the second to animal mind in disease. We may safely say that his work is, in some respects, the most important essay of the kind that has yet been undertaken. His observations have been supplemented by a thorough mastery of the history and literature of the subject, and hence his conclusions rest upon the broadest possible foundation of safe induction. There is a good analytical index to the book, as there ought to be to every work of the kind.”—New York Evening Post.

“It has been the author’s task to furnish here a small and convenient but very complete glossary of those terms; and he has done this so well, both in his choice of terms for definition and in his clear exposition of their etymological and technical meaning, as to leave nothing to be desired in this direction.”—New York Evening Post.