118 GENEKAL VIEW AND BASIS OF SCIENTIFIC RESEARCH. 



quickly, and without the expenditure of commensurate 

 labour and skill ; an undue desire for fame ; a hankering 

 after showy results, &c. One of the first persons who re- 

 ceived an electric shock from a Ley den jar was so misled 

 by enthusiasm that he affirmed he would not receive a 

 second for the value of a kingdom. And an eminent 

 physician (Dr. Pearson), when the metal potassium was 

 first isolated by Sir Humphry Davy, poising a piece in his 

 hand, was misled by a preconceived notion of the great 

 specific gravity of all metals, and exclaimed, c Bless me, 

 how heavy it is I ' whereas potassium is lighter than water. 



Errors arise not only from the unregulated activity 

 of our powers, but also from inactivity. Some scientific 

 investigators, however, are so enthusiastic in the pursuit 

 of truth that they overwork themselves ; by neglecting 

 also to attend to the signs of fatigue they blunt the sense 

 of perceiving it, until at length they seriously injure their 

 powers before they are aware of it. 



A frequent error is to decide abstruse and novel ques- 

 tions by ' common sense.' ' The common sense of edu- 

 cated mankind at one time denied the circulation of the 

 blood, and pronounced the earth to be the immovable 

 centre of the universe. At the present day it upholds 

 errors and absurdities innumerable, and common sense has 

 been well characterised as the name under which men 

 deify their own ignorance. Are scientific men never to 

 step over a rigid line, to refrain from investigation, be- 

 cause it would clash with common-sense ideas ? How 

 far should we have advanced in knowledge if scientific 

 men had never made known new discoveries, never pub- 

 lished the results of their researches, for fear of outraging 

 the common sense of educated mankind ? ' c Can the 

 wildest dreams of the spiritualist ask credence to anything 

 more repugnant to common sense than the hypotheses 



