1898J SOME NEW BOOKS 421 



to the historian of the future. The successes have been in an in- 

 creased knowledge of the facts and governing principles of the world 

 around us, and in the application of them to our henetit. The failures 

 have lain chiefly in the Hold of social economy, in which the advance 

 has been incommensurate with that in the region of physics. 



The striking feature of the century has been the discovery and 

 application of scientific and mechanical principles entirely unknown 

 to previous ages ; discoveries comparable to the invention of fire, of 

 writing, of geometry, or of printing; applications that have revolu- 

 tionised the mode of life of nearly all the world, bringing changes both 

 wide and deep where change had been unknown for centuries, or even 

 for millennia. Chief among these are the means of communication by 

 railways, steamships, the electric telegraph, and the telephone. Then 

 come modes of lighting, friction matches, gas light, and electric light. 

 The knowledge of light itself, and its action on matter, with the 

 marvellous applications to photography, the liontgen rays and spec- 

 trum analysis, by which last our knowledge of the distant universe 

 has been so enormously extended in so many directions. Minor 

 mechanical inventions of a novel order are the phonograph, the type- 

 writer, and the cycle. Among scientific theories, whose practical 

 application, though not always so direct or obvious, has profoundly 

 altered our ways of thought, or given us fresh mastery over matter, 

 Mr Wallace notes the following : — The doctrine of the conservation 

 of energy ; the molecular theory of gases ; the atomic theory as the 

 foundation of modern chemistry ; the uses of dust ; a knowledge of 

 meteors and the meteoritic theory of the universe (the latter perhaps 

 not so generally accepted as to have a right to rank in the present 

 category) ; the hypothesis of a glacial epoch (in which also Mr 

 Wallace goes further than many admit); the vaster conception of 

 the antiquity of man ; the cell theory and the theory of recapitula- 

 tion in embryology (where, likewise, a hint of recent criticism would 

 not have been misplaced) ; the germ-theory of disease and the func- 

 tion of leucocytes, from which conceptions Mr Wallace, not quite 

 fairly, separates antiseptic surgery ; the use of anaesthetics ; and the 

 acceptance of the theory of organic evolution, an acceptance due 

 chiefly to the labours of Darwin, whose " work will always be con- 

 sidered as one of the greatest, if not the very greatest, of the scientific 

 achievements of the nineteenth century." 



This first half, or rather, less than half, of the book is a well- 

 balanced and thoroughly interesting review, making its chief appeal 

 to the ordinary intelligent reader. It might have been written, per- 

 haps not quite so well, by any competent man of science. The second 

 section of the book, dealing with the failures of the century, could 

 have been written only by Mr Wallace. As an expression of the con- ' 

 victions of an eminent naturalist and thinker on many of the most 

 important problems of our day, it has a value by virtue of that personal 

 element, and demands the attention of all, whether they agree with 

 its opinions or no. The list opens curiously with a strong statement 

 of the case for phrenology, the neglect of which is regarded as one 

 of the chief failures; the chapter undoubtedly provokes one to a re- 

 consideration of the subject. Of similar nature is the opposition to 

 hypnotism and physical research, so prevalent among scientific men. 



