INTRODUCTION 



BY G, SIMS WOODHEAD, M.A. M.D., 



PROFESSOR OF PATHOLOGY, CAMBRIDGE. 



who have once attempted to catch 

 a glimpse of the wonderful secrets that 

 Nature will unveil to the earnest and discreet 

 searcher can never again look upon things as 

 common or of little importance because they 

 do not display to the eye of the superficial 

 observer the beauties that lie hidden under an 

 unattractive appearance or are shrouded in size 

 so minute that the ordinary eye is incapable of 

 discerning their exquisite plan and detail. 



The ingenious and beautifully finished works 

 projected by the human brain and brought into 

 being by the human hand attract our attention 

 and compel our admiration. We are constrained 

 to admit that the telescope, the microscope, the 



