438 A SHORT HISTORY OF SCIENCE 



jacent rocks are also affected ; so that the contrast in the relative 

 degree of disturbance in the more ancient and the newer strata, is 

 one of many proofs that the convulsions have happened in different 

 eras, and the fact confirms the uniformity of the action of subter- 

 ranean forces, instead of their greater violence in the primeval ages. 



The science of Geology is enormously indebted to Lyell more so, as I believe, 

 than to any other man who ever lived. Darwin. Autobiography. 



Pour juger de ce qui est arrive, et meme de ce qui arrivera, nous n'avons qu'a 

 examiner ce qui arrive. Buffon. Theorie de la Terre. 



I. SOME INVENTIONS OF THE EIGHTEENTH AND NINE- 

 TEENTH CENTURIES. APPLIED SCIENCE AND ENGINEERING 



He who seeks for immediate practical use in the pursuit of science, may be 

 reasonably sure that he will seek in vain. Complete knowledge and complete 

 understanding of the action of the forces of nature and of the mind, is the 

 only thing that science can aim at. The individual investigator must find 

 his reward in the joy of new discoveries ... in the consciousness of having 

 contributed to the growing capital of knowledge. . . . Who could have 

 imagined, when Galvani observed the twitching of the frog muscles as he 

 brought various metals in contact with them, that eighty years later Europe 

 would be overspun with wires which transmit messages from Madrid to 

 St. Petersburg with the rapidity of lightning, by means of the same principle 

 whose first manifestations this anatomist then observed. Helmholtz. 



The place of inventions in the history of science is hard to define. 

 Conditioned as they doubtless are by a favorable environment 

 at least for survival - - they do not always obviously arise as a direct 

 or logical consequence of preceding discoveries, or even of known 

 principles, but seem sometimes to spring almost de novo from the brain 

 of the inventor. And yet such an origin is probably more apparent 

 than real. The steam-engine could hardly have come from Watt 

 without Newcomen and Black as his predecessors, the telegraph from 

 Morse or the telephone from Bell except after Franklin, Oersted and 

 Faraday. Probably the truth is that if we only knew all the facts, 

 instead of only some of them, we should find every invention the 

 natural descendant, near or remote, of science already existing. And 

 as inheritance often seems to skip a generation or two and children 



