influence of these books and of personal travelling reminiscences upon English poetry and prose fiction. Defoe's Robinson Crusoe, Swift's Gulliver's Travels, Coleridge's Ancient Mariner, Michael Scott's Tom Cringle's Log, Charles Kingsley's Westward Ho!, Charles Reade's The Cloister and the Hearth, R. L. Stevenson's Treasure Island, are typical examples, and the list might be endlessly extended. Every poet of the nineteenth century, from Wordsworth to Tennyson and Browning, has left upon his pages some impression of his travels. From Fielding to Stevenson one may dip into the novelists almost at random to find sketches of travel. The first chapter of Guy Mannering is a vivid picture of a Scottish journey. Tom Jones and Humphrey Clinker take us along the country roads of England. Vanity Fair gives a picture of continental travel before the days of railways: Pickwick is fresh with the more homely humours of the English roadside and coaching inn. Upon another plane, Charles Lever's wanderings inspire his pen. Later literature abounds with smaller books of the same family-fictitious or half-fictitious stories of trips on foot or bicycle, in canoe or caravan, at home and abroad.

One other reflection occurs. Although the literature of travel is not the highest kind, and, indeed, cannot be called a distinct branch, of literature, yet a history of English literature rightly assigns a space apart to such books, because this kind of writing, perhaps more than any other, both expresses and influences national predilections and national character. In view of the magnificent achievements and splendid records of other nations who have preceded or accompanied the British in the fields of travel and discovery, it would be most inappropriate to attempt any kind of national comparison. But books of travel and books inspired by travel have, probably, been more read in Great Britain than any other books except novels. The educational value of pleasant travel-books is great. They have provided the substance of a thousand books for boys; and thus, both directly and indirectly, have guided and fired the inclinations of many generations of boys. And every reader, whether boy or man, finds in his favourite books of travel some image of himself and some hint towards moulding himself.

CHAPTER VIII

The Literature of Science

A. PHYSICS AND MATHEMATICS

HE brilliant achievements of British mathematicians,

TH

astronomers and physicists under the influence of Isaac Newton were followed by a long period of comparative inactivity. This was largely due to the fact that, during a considerable part of the eighteenth century, members of the British school were, more or less, out of touch with their continental contemporaries. A free exchange of views is essential to vigour and, the more varied the outlook and training of those concerned, the more fruitful is the intercourse. The effect of this isolation, moreover, was intensified by the manner in which English writers strove in their demonstrations to follow Newtonian forms. If Newton, in his Principia, confined himself to geometrical proofs, it was because their validity was unimpeachable; and, since his results were novel, he did not wish the discussion as to their truth to turn on the methods used to demonstrate them. But his followers, long after the principles of the calculus had been accepted, continued to employ geometrical proofs, whenever it was possible, even when these did not offer the simplest and most direct way of arriving at the result.

In short, we may say that, in the course of English mathematical science, the last seventy years of the eighteenth century form a sort of isolated backwater; for this reason, it is unnecessary here to describe in detail the work of the writers of this period. We must not, however, fall into the error of thinking that, among them, there were no men of ability. The investi

gations of Colin Maclaurin, of Edinburgh, on attractions, are excellent, and his treatise on fluxions is, perhaps, the best exposition of that method of analysis. We may also refer to the work of Thomas Simpson, of London, on the figure of the earth, tides and various astronomical problems; of John Michell, of Cambridge, who determined the law of force between magnetic poles, invented the torsion balance and devised the plan of determining the density of the earth carried out by Cavendish in 1798; of Henry Cavendish,' who discovered the law of attraction in static electricity, introduced the ideas of electrostatic capacity and specific inductive capacity and determined the density of the earth by his well-known experiments; and of Joseph Priestley,' who also discovered, independently of others, the law of attraction in electrostatics and the existence of oxygen; while, in observational astronomy, we need only refer to the great achievements of James Bradley and (Sir) William Herschel. In applications of science, this period and the early years of the nineteenth century were notable for the development of the steam-engine. Somewhat earlier, Thomas Savery and Thomas Newcomen had done much to bring it into practical use; but modern forms may be said to date from the improvements introduced by James Watt, Richard Trevithick and Henry Bell.

With the nineteenth century, a new era in the history of mathematics and theoretical physics in Great Britain opened. We shall deal here only with its main features, and, so far as possible, shall avoid technical details. Unfortunately, limits of space forbid the introduction of those biographical touches which would have added to the human interest of the story we have to tell.

The first thirty or thirty-five years of this period were largely occupied with work preparatory to the outburst of activity that characterised the Victorian renascence. Early in the nineteenth century, the use of analytical methods was introduced in the Cambridge mathematical curriculum. The advocacy of this change, originated by Robert Woodhouse, was warmly taken up by George Peacock, Charles Babbage, (Sir) John Herschel, William Whewell and (Sir) George Airy. These men worked under the influence of the great French * See section B of the present chapter.

school, of which Lagrange and Laplace are the most prominent members, and were hardly affected by their contemporaries, such as Gauss, Abel and Jacobi, who were then creating new branches of pure mathematics. In England, at the beginning of the century, Cambridge was recognised as the principal mathematical school: all the reformers were residents there, and they directed their efforts mainly to the introduction of a free use of analysis in the university course of study. They were successful; and, by 1830, the fluxional and geometrical methods of the eighteenth century had fallen into disuse. The leadership of Cambridge in this change was undisputed, and the employment of analytical methods became usual throughout Great Britain.

In these years, a good deal of interesting work in physics and chemistry was done in London, where the Royal Institution in its laboratories offered far better opportunities for research than any similar body in Britain. In connection with this society, we may mention the work of Thomas Young, whose investigations on wave motion prepared the way for the acceptance of the undulatory theory of light, and we may associate with him the names of (Count) Rumford and (Sir) David Brewster; optics and heat being the subjects to which their special attention was directed. At the same time, John Dalton,' in Manchester, was studying the expansion of gases under varying changes of pressure and temperature, and the tension of vapours.

At this time, interest in natural philosophy was widely disseminated, and, in science, as in politics and literature, new ideas were readily welcomed. Institutes and scientific societies were founded everywhere, and popular lectures by experts spread broadcast general, though somewhat vague, information on natural philosophy and astronomy. The year 1831 is memorable for the foundation of the British Association for the Advancement of Science. The intention of its promoters was that the Association should meet every year for a few days at a provincial town under a distinguished president, with the object, partly, of encouraging personal intercourse between leading men of science and, partly, of promoting interest in scientific work in the various localities where meetings were • See section B of the present chapter.

held. The meetings led to the regular appointment of expert committees instructed to report on the progress in various subjects; these reports have been, and are, of permanent value.

By way of addition to this preliminary statement, we may also, in passing, mention the History of the Inductive Sciences, published by Whewell in 1837. It put together in a readable form the leading facts connected with the history and growth of science, and, though open to criticism on questions of details -as was inevitable in the case of an encyclopaedic work of the kind-it served a useful purpose. Hardly less important was The Penny Cyclopaedia, issued in twenty-seven volumes in 1833-43 with three supplements.

The most notable physicist at the beginning of the Victorian period was Michael Faraday,' who, in 1831, had begun those investigations on electricity which have altered our conceptions of the subject, and, by their applications, have revolutionised industrial science. Faraday had been brought up in humble circumstances, and his career is interesting as an illustration of the fact that, in England, no door is closed to genius. In 1812, after attending some lectures delivered by Sir Humphry Davy, he sent notes of them to Davy, asking his assistance to enable him to study science. The result was that Davy employed him as an assistant in the chemical laboratory in the Royal Institution. Here, Faraday's experimental skill soon led to appreciation of his powers, and he wrote various papers on scientific questions.

Faraday's earliest electrical work related to induced currents, and depended on his discovery of the fact that, if a wire in the shape of a closed curve is moved to or from another wire through which an electric current is flowing, a current is set up in the former wire which ceases so soon as the motion ceases. The induced current is caused by and depends on the motion of the one wire relative to the other. Magnetic effects can be similarly produced. Faraday went on to explain various phenomena by the action of the induced currents which he had discovered. As he pondered on possible explanations of these results, it occurred to him that all space might be filled by lines of magnetic force, every line being a closed curve passing through the magnet to which it belongs; and he pointed out See section B of the present chapter.