FIFTY YEARS OF AMERICAN SCIENCE 13 



the microscope, so the physicist finds himself nearing the point 

 at which the definite constitution of matter must begin — the 

 real sunrise of the material universe, beyond which lies chaos 

 only. Considered in their concrete application, the figures are 

 still more significant. The uses of liquid air for wholesale 

 cooling, as an adjunct in chemical and metallurgical opera- 

 tions, and even as a terrible instrument of war, have already 

 been tested or suggested; yet the stimulus of discovery has 

 hardly begun to affect the mass of inventors. 



As doctrinal prejudice melted, and as chemistry estab- 

 lished the continuity between organic and inorganic substan- 

 ces, the sum of experience and weight of reason wrought a 

 revolution in thought, and the dominion of law over living 

 matter was soon accepted implicitly, if not explicitly. The 

 extension of law into the realm of intellectual processes came 

 later, and more tediously and haltingly. A noteworthy step 

 was taken in 1859, when Joseph Le Conte illustrated certain 

 cases of interconvertibility of physical and mental forces. His 

 exposition was republished and widely reviewed and discussed 

 in Europe, where it inspired experiments and the making of 

 special apparatus — always the strong side of transatlantic 

 research ; for the European pioneer puts stepping stones where 

 the American lays a bridge. Meantime, Barker, after demon- 

 strating the interconvertibility of physical and vital forces in 

 1875, passed into the higher realm, and definitely extended 

 the correlation to mental force. Other contributions followed ; 

 and while there are still those who dread to lift the veil of 

 mystery above a certain point — perchance through confound- 

 ing mental process and intellectual product — the more vigor- 

 ous investigators recognize the physical basis of mentation, 

 and a science of psychology has arisen, standing to meta- 

 physical psychology much as astrology stood to astronomy 

 and alchemy to chemistry. It is represented fittingly in 

 America. The consequences and applications of this advance 

 of the half century may no more be foretold than those of 

 others newly made ; yet even if it mean no more than the exten- 

 sion of law into a new realm, and the replacement of chaos by 

 order in human thought, it must take an important place in 

 the history of science. 



