396 BRAIN WORK AND 



In short, in each branch of science a revision 

 of the current theories as well as new wide 

 generalisations are wanted. And if the revi- 

 sion requires some of that inspiration of genius 

 which moved Galileo and Newton, and which 

 depends in its appearance upon general causes 

 of human development, it requires also an 

 increase in the number of scientific workers. 

 When facts contradictory to current theories 

 become numerous, the theories must be revised 

 (we saw it in Darwin's case), and thousands 

 of simple intelligent workers in science are 

 required to accumulate the necessary facts. 



Immense regions of the earth still remain 

 unexplored ; the study of the geographical dis- 



the glaciation of Europe. Agassiz came forth with the glacia- 

 tion of the Alps, the Jura mountains, and Scotland, about 1840 ; 

 and five years later, Guyot had published his maps of the routes 

 followed by Alpine boulders. But forty-two years elapsed after 

 Venetz wrote before one geologist of mark (Lyell) dared timidly 

 to accept his theory, even to a limited extent the most interest- 

 ing fact being that Guyot's maps, considered as irrelevant in 1845, 

 were recognised as conclusive after 1863. Even now more 

 than half a century after Agassiz's first work Agassiz's views 

 are not yet either refuted or generally accepted. So also Forbes's 

 views upon the plasticity of ice. Let me add, by the way, 

 that the whole polemics as to the mscosity of ice is a striking 

 instance of how facts, scientific terms, and experimental methods 

 quite familiar to building engineers, were ignored by those 

 who took part in the polemics. If these facts, terms and 

 methods were taken into account, the polemics would not have 

 raged for years with no result. Like instances, to show how 

 science suffers from a want of acquaintance with facts and 

 methods of experimenting both well known to engineers, florists, 

 cattle-breeders, and so on, could be produced in numbers. 



