jai TABLE OF CONTENTS 



PART II. SCIENCE OF THE COMMUNITY 



SECTION A. MEANS OP TRAVEL 

 Group A . Travel on Lund 



XVI. THE LOCOMOTIVE 243 



XVII. THE ELECTRIC TROLLEY 257 



XVIII. THE AUTOMOBILE 266 



Group B. Travel by Water 

 XIX. THE STEAMBOAT AND .SUBMARINE . . . .284 



Group C. Travel by Aw 

 XX. AIRSHIPS AND AIRPLANES 300 



SECTION B. MEANS OF COMMUNICATION 

 XXI. THE TELEGRAPH ....... 318 



XXII. THB TELEPHONE 333 



SECTION C. THE HEALTH OF THE COMMUNITY 



XXIII. THE PUBLIC WATER, MILK, AND FOOD SUPPLY . 347 



XXIV. CONTAGIOUS DISEASES 365 



XXV. INSECTS AND DISEASE 394 



XXVI. HEALTH OFFICERS 417 



XXVII. SCHOOL HYGIENE 426 



SECTION D. COMMUNITY ENTERTAINMENT 

 XXVIII. THE MOVING PICTURES 444 



SECTION E. CONSERVATION OF COMMUNITY RESOURCES 



XXIX. PROTECTION OF BIRDS 459 



XXX. CONSERVATION OF FORESTS 478 



