EMPIRICAL KNOWLEDGE, EXPLANATION, &c. 165 



the same way. Cultivation 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 pro- 

 ducing an unusually fine variety. Even the use of fire 

 must, some time or other, have been discovered in a like 

 accidental manner. 



With the progress of any branch of science, the element 

 of chance becomes much reduced. Not only are laws 

 discovered which enable results to be predicted, as we 

 shall shortly consider, but the systematic examination of 

 phenomena arid substances often leads to important and 

 novel discoveries, which can in no true sense be said to be 

 accidental. It has been asserted that the anaesthetic pro- 

 perties of chloroform were disclosed by a little dog smelling 

 at a saucerful of the liquid in a chemist's shop in Linlith- 

 gow, the singular effects upon the dog being reported 

 to Dr. Simpson, who turned the incident to such good 

 account. This story, however, has since been shown to 

 be a fabrication, the fact being that Dr. Simpson had for 

 many years being endeavouring to discover a better anaes- 

 thetic than those previously employed, and that he tested 

 the properties of chloroform, among other substances, at 

 the suggestion of Mr. Waldie, a Liverpool chemist. The 

 valuble powers of hydrate of chloral have since been dis- 

 covered in a like manner, and systematic inquiries are 

 continually being made into the therapeutic or economic 

 value of new chemical compounds. 



If we must attempt to draw any conclusion concerning 

 the part which chance plays in scientific discovery, it 

 must be allowed that it more or less affects the success of 

 all inductive investigation, but becomes less important 

 with the progress of any particular branch of science. 

 Accident, too, may bring a new and valuable combination 

 to the notice of some person who had never expressly 

 searched for a discovery of the kind, and the probabilities 



