xiv INTRODUCTION 



affected practical life in the various and widely 

 distinct branches of human effort. 



In such a presentation it was inevitable that 

 Chemistry should take the first place. Its growth 

 during the last half century has been startlingly 

 rapid in Pure Science, but even this is dwarfed 

 by its achievements in Industrial Life where in 

 the shape of dyes, pharmaceutical and photo- 

 graphic products it has forced itself upon the atten- 

 tion of every member of the community. The 

 claims of Physics secure for it a right to the second 

 place. Considered as a whole it has done more to 

 mould industrial life than any other department 

 of Science. But its triumphs came earlier than 

 those of Chemistry and the progress of Physical 

 Science during the last 50 years would not strike 

 the ordinary observer with any comparatively 

 equal effect were it not that electricity in the 

 shape of telegraphy, electric light and engineering 

 has changed the whole possibilities of human 

 existence within that time. Those who doubt 

 this had better try to picture to themselves what 

 would have been the course of the present War 

 had electricity in the shape of telegraphy and 

 engineering not existed. 



It is not my intention to refer specifically to 

 the individual Essays contained in this volume but 

 I have derived special pleasure from the group that 

 deals with organic life in health and disease. This 

 constitutes the most recently captured domain of 



