GEOLOGY AS A BRANCH OF GENERAL

EDUCATION.

"The study of the structure of the Earth must tend to enlarge the mind of man, in seeing what is past, and in foreseeing what must come to pass in the economy of nature; and here is a subject in which we find an extensive field for investigation, and for pleasant satisfaction.”—HUTTON's Theory of the Earth, 1795.

IN the present Chapter I mean to direct attention to "Geology as a Branch of General Education;" to the necessity of its being taught in our schools, academies, and colleges; to its importance both as a means of intellectual training and as a special preparation for engaging in some of the most essential departments of human industry. In this task I have to appeal at once to the geologist who understands the nature and bearings of his science, and to the public, who have only a general notion that geology has something to do with the rocky structure of our planet, and with the curious fossils, minerals, and metals that may be occasionally discovered therein. For this purpose I must speak plainly, and, at the outset, endeavour to explain the true purport of geological investigation. Much of what I have to say may, in all likelihood, be known and felt by many of my geological readers, but I address myself less perhaps to them than through them to the public, and am anxious to obtain the sanction of their approval, that

it may give further weight to the views I am endeavouring to inculcate.

What, then, are the aim and object of geology? What does it profess to teach? What are its certainties, and how far can these claim the acceptance of the educated or well-informed mind? In general terms, as most people are now aware, the object of geology is to discover the constitution and unfold the history of our planet. What are the materials of which this earth is composed; what are the causes which have led to their formation and present arrangement; what the nature of the vegetable and animal remains they entomb, as compared with those now peopling the land and waters; what evidence do these afford of past change and progress; and, combining the sum of such evidence, what is the history of our globe from the current hour to the earliest moment of which we have record in the rock-formations we investigate? This is Geology: it grasps the whole earth in its plan; it is the Physical Geography of former ages, and endeavours to depict the successive phases of the world's past, just as the geographer depicts the phases of the present. And while intellectually reading this world-history in the hills and plains, in the ravines and river-estuaries, in the beetling sea-cliffs and sandy shores-while reinvesting the earth with its former aspects of vegetation, and peopling it with the animal forms long since extinct geology, like a willing workman, is not ashamed to stoop in the quarry and toil in the mine for those minerals and metals which administer so much to our necessities, and confer the luxuries of wealth and power on every nation that has learned to apply them. Our science has thus a purely scientific aspect and a practical aspect -one which appeals to the intellect and the pleasure of knowing, another that is applicable to the industrial purposes of life, and indispensable to their advancement; one

that appeals to the student, another to the miner, engineer, architect, agriculturist, and others, who have to deal with the earth's crust and the substances that compose it.

Such are the leading objects of geology, and though one of the youngest of the natural sciences, it is already in possession of much interesting world-knowledge, and has many important teachings to impart. It teaches, for instance, that the dry land of this terraqueous surface is subject to incessant change of aspect through the agencies of air and water—that organic and chemical forces are also perpetually sorting and reassorting the earth's materials, and that the vulcanic forces from within are as ceaselessly upheaving and reconstructing what the air and water, and other agents from without, are wasting and wearing down. It teaches that this terrestrial crust is ever held in habitable equilibrium between these contending forces that sea and land are slowly but unceasingly changing places-that the continents of the present day are but the sea-formed sediments of former ages, and that the ocean now rolls over the submerged surfaces of former lands. It finds, moreover, remains of plants and animals in these ancient sediments as evidence of the kind of life that then prevailed, and in these ancient volcanic upheavals traces of the extent and power of the forces that operated. In this way the rocks of the earth's crust became, as it were, the leaves of a great record impressed with evidence both physical and vital of the past conditions of our planet; and to arrange this record in chronological order, to interpret the facts aright, and to arrive at something like a connected history of the whole, is the sum and substance of all sound geology. True geology has nothing to do with the origin of matter or the formation of the universe, but restricts itself to the appearances in the earth's crust-tracing back from the recent to the remote, and from the remote to the remoter

still, till all traces of change become obliterated, and the further history of our planet is lost in obscurity.

Proceeding upon this inductive method, geology has arrived at most important results in world-history, and its certainties, now rapidly on the increase, are such as must commend themselves to every inquiring mind. It teaches what no other science could have taught, and what, for instance, had formerly never been dreamed of: First, That the earth's crust is in a state of ceaseless change, and that the causes-meteoric, aqueous, igneous, chemical, and organic that now operate have been productive of similar changes in all time past. Second, That these changes are governed by imperative laws, and that the mineral structure of the globe arising therefrom has consequently a definite and determinable arrangement. Third, That this arrangement, as displayed in the numerous rock-formations, implies an enormous lapse of time, and therefore establishes an antiquity for our globe far beyond all previous conception. Fourth, That during the long periods which these successive formations imply, the earth has been peopled by different races of plants and animals-all evidently belonging to the same great scheme of life, but varying widely in their characteristics during each succeeding epoch. Fifth, That during these periods there has been an ascent, in the main, from lower to higher forms; and that the plants and animals now inhabiting the globe are, on the whole, higher and more specially organised than the plants and animals of any former period. Sixth, That these successive appearances and distributions of plants and animals are connected together by some great law of development which, though not yet satisfactorily discovered, is evidently bound up with the operating forces of the universe. And, lastly, The earth being still subjected to the same causes of change that operated in time past, the future aspects of our planet must

differ from the present physically and vitally, and its present living races give place to others of a still higher and more specialised organisation.

Modern geology, however, has not only attained to high scientific truths, but its deductions are also capable of important practical application. The minerals and metals upon which so much of the progress and amenities of civilisation depend, are all derived from the crust of the earth; and as they are not scattered at random in that crust, but are found in certain formations, or in veins that hold determinate positions, it is of vast importance to know where they exist, and with what facilities they can be obtained. Geology is the great index - finger to this kind of information; and just as its deductions become more widely known-just as its maps and sections are more studied and better understood-so will mining adventures be conducted with greater certainty and safety. But it is not to the miner alone that the science is of practical importance. The engineer, in tunnelling through hills, cutting railways, excavating canals and harbours, and sinking for water, derives valuable aid from its deductions; the architect is also assisted in his search for abundant and durable materials; while the agriculturist, gardener, and others who have to deal with lands and soils, may profit greatly by a knowledge of its truths. To the landscape gardener and painter it likewise affords important hints, some acquaintance with the rocks that give shape and character to the landscape being as necessary to them as a knowledge of anatomy to the delineator of the human figure. In this way geology becomes not only of high intellectual or scientific interest, but of direct and practical value; and claims, as strongly as any of the natural sciences can claim, an important place in the curriculum of modern education.

What I mean by a place in the curriculum of modern