CHEMISTRY AND CIVILIZATION 157 



the effect of a scientific invention upon civilization, we must 

 proceed rather differently than would the historian of philo- 

 sophic or religious, economic or political, development. In 

 exact science, at least, no hypothesis can be so erroneous as 

 to work practical harm, except possibly by retarding the adop- 

 tion of a correcter view; and who would try to estimate the 

 amount of such retardation? Based upon the observation 

 of solid facts, a hypothesis is accepted so far as it seems to 

 connect them with one another, but receives scant attention 

 so long as it does not lead to equally positive results. A false 

 ethical, economic or political theory may enjoy universal 

 credence for generations, before its evil effects upon the 

 commonwealth shall have been recognized and corrected 

 by what is usually termed reformation or revolution. Scien- 

 tific thought has a scarcely perceptible influence upon a peo- 

 ple; it is the practice by which they are helped or harmed. 

 For this reason, the scientific discoverer must be content to 

 see his work popularized by the inventor, and the Wollastons, 

 Henrys and Hertzes are unknown to those for whom Daguerre, 

 Edison and Marconi are household words. 



The influence of a scientific invention, put to practical use, 

 may be felt in various directions: it may assist the culture of 

 the individual, by opening up new channels of thought or 

 providing new means of aesthetic enjoyment; it may increase 

 our physical comfort, by placing in our hands new weapons 

 wherewith to combat hunger, disease, heat, cold, and other 

 elemental forces; it may modify the intercourse of individuals 

 and peoples, by devising new modes of communication and 

 transportation; it may dislocate political relation, by creating 

 more potent engines of offense or defense; it may, tempo- 

 rarily at least, profoundly alter the commercial prosperity of 

 whole provinces, creating new sources of wealth in one local- 

 ity, and depreciating the product of another; finally, it may 



