Among educational works which are calculated to afford real assistance to the teacher in his all-important labours, we may recognise two distinct classes. One  of these includes the "text-books," which should aim at presenting only the accurate and well-proportioned outlines of a system of instruction, leaving it to the teacher himself so to fill in these outlines with explanation and illustration, as to cause the new facts and reasonings to produce the most vivid and abiding impressions upon the minds of his pupils. But inasmuch as the attainment of such a result demands much practical skill and educational tacta skill and tact which are by no means easy of acquirementthe necessity and value of another class of works becomes manifest. This second class of educational works comprises such as aim at instructing the teacher how best to perform his difficult task; which exemplify the work of explanation, illustrate the art of illustration, and show how the dry bones of barren facts may, by clear arrangement and logical connection, be compacted into a body of real knowledge, and this body by being infused with the earnest intelligence of the teacher, may be quickened into active and fruitful life in the minds of the scholars.
It is to this latter very important class of educational works that we should be inclined to refer the book before us, and we cannot therefore regard the designation of it as a "manual for students," which is borne upon its coverone for which we suspect that the author is not himself responsibleas either happy or judicious. That some instruction in the physical laws of that universe in which we are placed ought to form a recognised part of our system of elementary education has been again and again maintained and strongly insisted upon by scientific men, and by none more persistently or more urgently than by the author of the present work. When we reflect on the fact that to the man who has learnt to recognise, obey and apply these laws, Nature reveals herself as a helpful and bountiful mother, ever ready to aid him [i]n his industry, his arts, and his commerce; while to him who ignores or violates these laws she is known only as a terribly relentless and avenging goddess, ever thwarting his most earnest endeavours, and scourging him with plagues, pestilences, and faminesit is hard to realise how slowly the necessity for this instruction in natural knowledge has forced itself upon the minds of those who are responsible for the scheme of elementary education adopted in this country. But societythe machinery of which is every day becoming more complicated and more susceptible to those painful consequences which follow from the infringement of the laws of naturewill doubtless in the end demand, as indeed it has a right to do, that every unit in her organisation should be fitted so to play his part, as to avoid the danger to himself and others which the neglect or violation of natural laws invariably entails.
Almost every demand that the principles of physical science should be taught in our elementary schools, has been met with the objection that our knowledge of nature and her laws has in recent years grown to such an extent, and ramified into so vast a number of channels as to make any attempt to teach it to the young quite hopeless. As well might we point to the number of volumes in the library of the British Museum, and declare that their existence demonstrates the uselessness of teaching the art of reading. No one, of course, would desire that an epitome all the sciences should be taught to children; but what is demanded is that the methods of modern scientific thought should be made familiar to every mind, that a few leading and necessary truths should be taught concerning the world in which we live and the laws which control its potent forces (seeing that upon our knowledge or ignorance of these depends much of our happiness and success or our misery and failure in the adventure of life), and that, last but not least, the minds of all young people should be conducted within the threshold of the temple of natural knowledge, so that any among them that may be endowed with the necessary capabilities may learn there to dedicate themselves to the pursuit of science.
How can this elementary instruction in science be best imparted to the young? This is the important question which Prof. Huxley applies himself to answer in the work before us; and he accomplishes his object much better by means of example than he could by any amount of discussion of the general principles of the art of teaching. On several other occasions the author has indicated the importance of making a knowledge of the more striking phenomena of nature, those with which we come into contact in our every-day life, and which exercise the greatest influence on our daily occupations and experiences, the starting-point of our introduction to the world of scientific thought; and it is to this vestibule of the temple of natural science that he applies the name of "Physiography."
The author of the present work of course recognises that first principle of good teaching which consists in fastening at first on facts and ideas which are known and familiar, and from thence leading the minds of the student by a succession of steps, no one of which shall present any serious difficulties, up to those more unfamiliar observations and those less obvious deductions from them, which if presented in the first instance might startle and repel rather than attract the scholar. We must ask the reader himself to trace in the work before us how, setting out from the most striking and easily observed facts about the River Thames, Prof. Huxley shows his admirable skill in teaching by leading his readers through a series of reasonings couched in simple and untechnical, but always accurate and elegant, language, up to the grandest truths in physics, biology, geology, and astronomy; how, throughout, happy analogies and telling illustrations make the path of the scholar, light, easy, and pleasant; and how in all this nothing of the exactness and dignity of science is sacrificed to a desire to say those fine or funny things which are too often supposed to convert a prosy book into a "popular" one.
The teacher who takes these easy lessons in elementary science and simply repeats them to his scholars can scarcely fail to communicate some sound and useful instruction to them. But every competent and judicious teacher will prize Prof. Huxley's book rather as a model than as a "crib"and this is the light in which the author, we are persuaded, would desire that his work should be regarded by them. It is as easy, for example, to make the Mersey, the Severn, the Forth, or the Clyde the starting point of our studies of nature, as the Thames, and in Manchester, Bristol, Edinburgh, or Glasgow respectively, it is far better to do so; nor will any well-instructed teacher find the smallest difficulty in thus adapting his lessons to his  auditory. To such teachers as have never studied or thought on scientific questions themselves, our advice would be to content themselves with placing Prof. Huxley's book in their school-libraries, and not to run the risk of spoiling its teachings by filtering them through their own minds.
We have spoken at such length on the value of this work to the teacher, as to leave but little space for reference to its interest to the general reader, yet this is by no means small; to those who seek an "introduction to the study of nature," which shall be at the same time both sound and readable, exact and untechnical, we most heartily commend the work before us.
We are informed in the preface that the idea of this work has long been entertained, and its plan and methods frequently revolved in the mind of the author. It is probable that not a little of its present excellence is due to this slow maturation of its plan, assisted, as we learn that its development has been, by its embodiment in two successive courses of lectureson the shorthand notes of one of which the present book is based. In seeking for an editor to relieve him of the more trying labour of book making, Prof. Huxley has been fortunate in securing the services of Mr. Rudler, whose knowledge of a great number of branches of science is combined with much literary skill. To this cause we may attribute the small number of inaccuracies in either fact or expression which a careful perusal of the work has revealed. Such as do occur may be easily remedied in the new edition, which we have no doubt will soon be called for.
In concluding this notice we cannot refrain from congratulating its author upon the production of the work, and at the same time of assuring him that among all the labours he has undergone, and the sacrifices he has made on behalf of elementary education in this country, none is likely to produce more valuable and more enduring fruit than this much-needed model of the art of teaching the fundamental truths of natural science, the appearance of which at the present time we cannot but regard as being most opportune.
C. Blinderman & D. Joyce