viii PREFACE 



recently had occasion to observe, by ignoring all 

 the rest of a man's work and glibly labelling him 

 a mere popularizer. If the falsehood were not too 

 glaring, they would say the same of Faraday and 

 Helmholtz and Kelvin. 



On the other hand, of the affliction caused by 

 persons who think that what they have picked up 

 from popular exposition qualifies them for discuss- 

 ing the great problems of science, it may be said, 

 as the Radical toast said of the power of the Crown 

 in bygone days, that it " has increased, is increas- 

 ing, and ought to be diminished." The oddities 

 of " English as she is spoke " might be abundantly 

 paralleled by those of " Science as she is misunder- 

 stood " in the sermon, the novel, and the leading 

 article; and a collection of the grotesque trav- 

 esties of scientific conceptions, in the shape of 

 essays on such trifles as " the Nature of Life " and 

 the " Origin of All Things," which reach me, from 

 time to time, might well be bound up with them. 



The tenth essay in this volume unfortunately 

 brought me, I will not say into collision, but into 

 a position of critical remonstrance with regard 

 to some charges of physical heterodoxy, brought 

 by my distinguished friend Lord Kelvin, against 

 British Geology. As President of the Geological 

 Society of London at that time (1869), I thought 

 I might venture to plead that we were not such 

 heretics as we seemed to be ; and that, even if 



