4 THE CONDUCT OF 



being its own inspiration. This kind of honesty is no mental 

 evolution, but is practical, and is governed by principle. A man 

 may know all about Faraday's work, but until he can do even one 

 of the things accomplished by that great man, let him not take 

 the name of scientist. But let me not be misunderstood here. I 

 have been speaking of those who mistake the study of results of 

 scientific research for true science, which is a study of a very dif- 

 ferent kind. It is not required that a scientist should necessarily 

 be a demonstrator. He may not have the means at his disposal 

 for confirming his conclusions. For instance, Mr. R. A. Proctor 

 (who, perhaps, has been the originator of more real scientific work 

 amongst amateurs than any man in this country) is not a practical 

 optician, but, having studied the principles governing the refrac- 

 tion of controlled light in its passage through a series of prisms, 

 one day threw out the hint to Mr. John Browning, that, under 

 certain conditions of intensity, it was possible to obtain a 

 spectrum of highly refracted light by the reversal of the 

 rays through a double battery of prisms, if such battery were 

 constructed upon a given plan. His own words will give 

 the sequence : — " It is rather a singular circumstance, perhaps, 

 in the history of this S-shaped battery, that when I de- 

 signed it I had never even seen a spectroscope, showing that 

 it is not absolutely necessary to have handled and used a scientific 

 instrument to be able to devise a practical extension of its powers. 

 Mr. Browning made a battery on this design, and Mr. W. 

 Spottiswoode, who purchased the instrument, lent it to Mr. 

 Huggins. It so chanced, by another somewhat singular coin- 

 cidence, that I saw the solar spectrum (at least, a well-dispersed 

 spectrum) for the first time with this very instrument." We thus 

 see that science requires not merely an active memory, but, with 

 it, a thorough understanding of principles. The demand upon 

 the mental faculties increases with the amount of matter that has 

 to be submitted to them ; and the variety of such, calls for sound- 

 ness of judgment and absence of prejudice. This has been 

 recognised by all who have distinguished themselves in scientific 

 investigation, but in some cases to such a manifest extent, as to 

 lead to the belief that at one time or another they must have per- 

 verted their faculties, and said, " We are prepared unconditionally 



