CONTENTS. 



CHAPTER 1. 



PAGE 



INTRODUCTORY . . ... . . . i 



COLLECTION OF WATER FOR BACTERIOLOGICAL EXAMINATION . 4? 



CHAPTER II. 



QUANTITATIVE BACTERIOLOGICAL ANALYSIS . . . . 7 

 PREPARATION OF " WATER PLATES "..... 9 



CHAPTER III. 



THE MULTIPLICATION OF MICRO-ORGANISMS IN WATER . . 12 

 THE INFLUENCE OF 'LIGHT ON MICRO-ORGANISMS . . .14 

 THE INFLUENCE OF MOVEMENT AND REST ON MICRO-ORGANISMS 17 

 THE SEDIMENTATION OF MICRO-ORGANISMS . . . .18 

 THE DURATION OF LIFE OF MICRO-ORGANISMS . . .21 

 THE INFLUENCE OF THE CHEMICAL COMPOSITION OF A WATER 



ON THE NUMBER OF MICRO-ORGANISMS .... 22 

 THE ACTION OF ELECTRICITY ON BACTERIA .... 24 



CHAPTER IV. 



THE BACTERIAL CONTENTS OF THE VARIOUS SOURCES OF SUPPLY 26* 

 THE RELATION OF THE RESULTS OF A QUANTITATIVE ANALYSIS 



TO THE QUESTION OF POLLUTION . . . .30 



CHAPTER V. 



THE RELATION OF THE QUANTITATIVE ANALYSIS TO FILTRATION 



OF WATER THROUGH SAND . ... 33 



