38 SCIENTIFIC THOUGHT. 



the atomic view of matter. Similar uncertainties in 

 the definitions exist in both theories all through the 

 century, down to the most recent times. There are 

 those who still look upon both conceptions as merely 

 convenient symbolisms, as ideal instruments of thought 

 or scientific shorthand ; and on the other side we have it 

 as emphatically stated, that the question, What is ether ? 

 " is the question of the physical world at the present 

 time," " that it is not unanswerable," in fact, " that it 

 is not far from being answered," that " it is probably 

 a simpler question " than the other question, What is 

 matter ? l The whole domain of physical science is even 

 divided into two portions, the physics of matter and the 

 physics of ether, 2 and the older, more empirical, and 

 common - sense divisions, treating separately of light, 

 electricity, and magnetism, are assembled in one great 

 doctrine, the " doctrine of the ether." It is, indeed, 

 somewhat astounding, if not disheartening, to hear at the 

 same time from an authority who has done more than 

 any other living philosopher to enlighten us in these 



1 Professor 0. Lodge, in the 

 Preface to the first edition of 

 ' Modern Views of Electricity,' 

 p. xi. " It is simpler," he con- 



2 See inter alia Professor Paul 

 Drude's ' Physik des Aethers ' 

 (Stuttgart, 1894). In the Preface, 

 p. vi, he speaks of the philosophical 



tinues, " partly because ether is | " desire of using the same funda- 



one, while matter is apparently mental conceptions for the physics 



many ; partly because the presence ; of the aether as for the physics of 



of matter so modifies the ether that ; matter, whereby it remains an open 



no complete theory of the properties j question whether it is more service- 



of matter can possibly be given able to reduce the equations in the 



without a preliminary and fairly physics of the aether to those ex- 



complete knowledge of the pro- j pressioiis which can be got from the 



perties and constitution of undis- ! observable phenomena in the 



turbed ether in free space. When | physics of matter (the equations 



this has been attained, the resultant of dynamics), or whether the 



and combined effect we call matter ' opposite road can be chosen with 



may begin to be understood." advantage." 



