PREFACE. 



THE Bacteria are so often nowadays the 

 subject of discussion and discourse ; so much 

 which is at once disquieting and untrue is said 

 about them, and they are withal of such prac- 

 tical importance to the health and well-being 

 of everybody, that it has seemed to the writer 

 worth while to bring together in some simple 

 fashion a little of our knowledge about them. 



The aim then of this book is to present 

 some facts from a small corner of the domain 

 of Science in such form as will be plain to the 

 unscientific, and with these some extracts from 

 the lore of the physician which will, it is 

 hoped, be both interesting and useful to the 

 lay reader. 



T. M. P. 



iii 



144339 



