158 PROGRESS OF SCIENCE IN THE CENTURY. 



that electrical changes occurred in the contracting 

 muscle of the frog's leg ; in the last year of the same 

 century Volta of Pavia had shown that electricity 

 may be produced by the simple contact of two metals j 

 but, for a time, little resulted from the discoveries 

 of either of these pioneers. Another impulse was 

 necessary before the wheels of progress began to move, 

 and that was afforded in 1819, by Oersted, who 

 brought the known facts of electricity into touch 

 with those of magnetism, and initiated the movement 

 which has made the word electricity almost as charac- 

 teristic of the nineteenth century as the word evolu- 

 tion. 



Achievements. — Forestalling the rest of this sec- 

 tion, we may briefly state that the scientific study of 

 electricity initiated by Oersted and also by Ampere, 

 was profoundly influenced by the experimental 

 genius and scientific temper of Faraday, found 

 mathematical or precise formulation in the work of 

 Thomson (Lord Kelvin), and was developed into a 

 provisional dynamical theory by the extraordinary 

 insight of Clerk Maxwell. It is perhaps not too 

 much to say that what I^ewton did for gravitational 

 phenomena, was done by Clerk Maxwell for electrical 

 phenomena. The study was raised by him and his 

 collaborateurs from the observational and classi- 

 ficatory level to become an integral part of a unified 

 Natural Philosophy. 



Oersted. — Oersted (1777-1851) may be called 

 the founder of the science of electro-magnetism 

 because he succeeded in proving experimentally 

 (1819) what had been previously surmised, for in- 

 stance from the effect of lightning on compasses, — 

 that electrical and magnetic al phenomena are of the 

 same nature. In his famous experiment showing 



