6 MAY 1905, Page 21

FEW studies are more interesting than that of the way

in which the land has been moulded by natural influences, and in which its configuration has affected human history. We are accustomed to talk glibly of the solid earth, and to speak with the Psalmist of the unchanging hills. But in truth there is no such thing. As Tennyson put it, with his unerring eye for the basic truths of modern science, all our world is in a state of flux :—

" The hills are shadows, and they flow

From form to form, and nothing stands ; They melt like mist, the solid lands, Like clouds they shape themselves and go."

One of the chief functions of the geologist is to trace the stages of this unending secular process, and to show how it has influenced the formation of human character and the estab- lishment of nations. In his new volume of essays Sir Archibald Geikie—the acknowledged as well as the official chief of British geologists—devotes much of his unrivalled power of lucid exposition to the latter aspect of his important science. The first of these interesting papers deals with "Landscape in History," and it is followed by cognate essays on "Landscape and Imagination " and " Landscape and Literature,"—the last of which was delivered in 1898 as the Romanes Lecture at Oxford. In these Sir Archibald Geikie discusses the effect of the physical configuration of a country on the bodies and minds of its inhabitants :—

" The landscapes of a country, the form, height, and trend of its mountain-ranges, the position and extent of its plains and valleys, the size and direction of its rivers, the varying nature of its soils and climate, the presence or absence of useful minerals, nearness to or distance from the sea, the shape of the coast-line whether rocky or precipitous, or indented with creeks and harbours—all these and other aspects of the scenery of the land have contributed their share to the moulding of national history and character."

We have long realised some part of this great truth, which

has been expressed more or less distinctly by poets like Scott and Wordsworth, prose-writers like Ruskin and Kingsley, in their distinction between the racial types produced by mountainous or flat countries. Every one recognises the great difference, mental as well as physical, which must obtain between the inhabitants of the Scottish Highlands or the high Alpine valleys and those of the English fens

or the sea-threatened flats of Holland : between the hothouse Bengali and the hard-bitten farmer of the Punjab : between the sea-rover of the Scandinavian or Greek

fiords and the shepherd of the vast Chaldaean plains. But it is only of late years that the scientific basis of this essential difference has been worked out, and in Sir Archibald Geikie's interesting and eloquent pages it is admirably illustrated from the history and literature of our own islands. He shows us, for instance, how-

" while the original Celtic people, restricted to less ample territories and less fertile lands, have to a large extent retained the holdings and habits of their ancestors, building comparatively few towns, and engaging in few crafts, save farming and stock- raising, the Teutonic tribes, possessing themselves of the broad cultivable lowlands and the great repositories of coal and iron, have thrown across the islands a network of thoroughfares, have scattered everywhere villages and towns, have built many great cities, have developed the industrial resources of the land and have mainly contributed to the commercial supremacy of the Empire."

This is a very entertaining and useful field of research, in which we could desire no better guide than Sir Archibald There is, however, a precedent question : how did the land in which we live come to its present configuration ? It is the

function of the geologist pure and simple to answer this ques- tion. Sir Archibald Geikie has already done so, both in his well-known text-book and in his attractive account of The Scenery of Scotland. But there is still room for other (though similar) answers, and one of the best that we have

yet seen is contained in the text-book of geology of which the first volume has now been published by Messrs. Chamberlin and Salisbury, who are the heads of the Departments of Geology and Geography in the flourishing University of

• (1) Landscape in History, and other Essays. By Sir Archibald Eleikie. London : Macmillan and Co. [8s. 61. net.)—(2) Geology : Processes and these Results. By Thomas C. Chamberlin and Rollin D. Salisbury. London : John Murray. [21s. net.]—(3) A Study of Bccest Earthquake'. By Charles Davison. London : Walter Scott. [6s. net

Chicago. This first volume deals with the natural forces and processes now in operation to mould and change the features of the earth, whilst its successor will apply these principles to trace the history of past ages, and the emergence of the world we live in from the golden mist of the original nebula. The authors write very simply and clearly, and have brought an admirable wealth of illustration to bear upon their topic ; they have adopted the scientific principle of working from the present to the past, from the known to the inferred. Accordingly, they begin by studying the agents which are now steadily at work to alter the face of the world, of which the two most important are air and water. It may seem a hard saying that the gentle breeze which fans our cheek on a hot summer day, the sparkling brook of which we are glad to drink in the course of a mountain ramble, are competent to change the whole appearance of a continent, to level mountains and dig vast canons like that through which the Colorado River flows thousands of feet below the level of the surrounding country. Yet nothing is more clearly established than that all the main features of the earth as we now know it are attributable to the erosive and denuding action of air and water. The whole North-West of Ireland, for instance, was once buried under a sheet of millstone grit many hundreds of feet thick, of which the sole record is a little cake, some few acres in extent, on the wind-swept top of Slieve League. " Slowly and insensibly, by the fall of rain, the beating of wind, the creeping of ice-fields, and the surging of the ocean, hollow and glen have been carved out, bill after hill has emerged, like forms from a block of marble under the hand of a sculptor." Most of the great mountain ranges—the Alps, the Andes, and the Himalayas—represent the harder rocks that have been left standing nobly up whilst the softer strata have been carved away by the constant and secular action of air and water. But there was, of course, an earlier stage, in which the various rocks, hard and soft, were solidified from the gaseous nebula or the clash of warring meteorites which represented the earliest form of the earth to which science can look back with assurance. All this is clearly explained in Messrs. Chamberlin and Salisbury's volume, which is the more interesting to an English reader because its illustrations are mostly taken from the wide and various conformations of the United States, so that it is a helpful supplement to the English books on geology.

Amongst the causes which aid in modelling the world, there are some of a more violent or catastrophic kind, which are happily less common nowadays than they seem to have been in prehistoric times, though the occasional outburst of a Mont Pelee or a Krakatoa reminds us that the central fire is only dormant. Mr. Charles Davison contributes to their knowledge in his Study of Recent Earthquakes, the latest volume of the " Contemporary Science Series." In the nine chapters of this able and exact book he gives us a detailed account of the chief seismic convulsions of the past half- century,—those of Naples in 1857, Ischia in 1881 and 1883, Andalusia in 1884, Charleston in 1886, the Riviera in 1887, Japan in 1891, India in 1897, and the two small earthquakes which alarmed our own islands at Hereford in 1896 and Inverness in 1901. This is not a complete list, but it covers practically all the ground on which earthquakes add to our knowledge of the earth's inner structure, and its liability to sudden deformation. In a brief concluding chapter Mr. Davison sums up the characters of the typical earthquake, and points 'out that of the three causes to which these catastrophes are due—subterranean rock-falls, volcanic action, and the sudden yielding of strata under stress—the third is by far the most important in the history of the globe. We cannot help being awe-struck by vast earthquakes, like that which lately ravaged part of India ; but it is well to remember that "in the formation of a mountain-chain or continent, they serve no higher purpose than the creaking of a wheel in the complex movements of a great machine."