xxiv.] EMPIRICAL KNOWLEDGF, EXPLANATION, &c. 531 



the close it occurred to him to try the effect of placing 

 the conducting wire parallel to a magnetic needle, instead 

 of at right angles, as he had previously done. The needle 

 immediately moved and took up a position nearly at right 

 angles to the wire ; he inverted the direction of the 

 current, and the needle deviated in a contrary direction. 

 The great discovery was made, and if by accident, it was 

 such an accident as happens, as Lagrange remarked of 

 Newton, only to those who deserve it. 1 There was, 

 in fact, nothing accidental, except that, as in all totally 

 new discoveries, Oersted did not know what to look for. 

 He could not infer from previous knowledge the nature 

 of the relation, and it was only repeated trial in different 

 modes which could lead him to the right combination. 

 High and happy powers of inference, and not accident, 

 subsequently led Faraday to reverse the process, and to 

 show that the motion of the magnet would occasion an 

 electric current in the wire. 



Sufficient investigation would probably show that almost 

 every branch of art and science had an accidental begin- 

 ning. In historical times almost every important new 

 instrument as the telescope, the microscope, or the compass, 

 was probably suggested by some accidental occurrence. 

 In pre-historic times the germs of the arts must have 

 arisen still more exclusively in the same way. Culti- 

 vation of plants probably arose, in Mr. Darwin's opinion, 

 from some such accident as the seeds of a fruit falling upon 

 a heap of refuse, and producing an unusually fine variety. 

 Even the use of fire must, some time or other, have been 

 discovered in an accidental manner. 



With the progress of a branch of science, the element 

 of chance becomes much reduced. Not only are laws 

 discovered which enable results to be predicted, as we 

 shall see, but the systematic examination of phenomena 

 and substances often leads to discoveries which can in no 

 sense be said to be accidental. It has been asserted that 

 the anaesthetic properties of chloroform were disclosed by a 

 little dog smelling at a saucerful of the liquid in a chemist's 

 shop in Linlithgow, the singular effects upon the dog being 

 reported to Simpson, who turned the incident to good 



i Life of Faraday, vol. ii p. 396. 



M M 2 



