Plague Prevention by Extermination of Rats--General Uselessness of the Rat and Its Enormous Destructiveness, with Details of Trapping and Other Extermination Methods--The Manila Epidemic, 1912-1914--The First Cases--Unusual Character of Plague Cases at Quarantine--Clinical Description of Two Cases at Quarantine--Inauguration of the Manila Epidemic--Directed to Take Charge of Plague Suppression in Manila--Plague Fighting Organization--Method of Rat Proofing and Rat Destruction--Correspondence Between Dr. Jackson and Dr. Heiser, Director of Public Health--Observations on Fleas and Their Habits--Conditions of Habitations in Manila Favoring Rat Multiplication and Spread of Plague--Comparative Statistics on Methods of Catching Rats--The Natural Enemies of the Flea--Zoölogic Classification of Rats--A Collection of Notes Concerning Rat Runs, Rat Nests, Multiple House Infections and Other Data--Sample of Detailed Orders Issued Regarding Rat Extermination--Method of Procedure of Collecting and Forwarding Rats Suspected of Plague Infection to Laboratory--Memoranda in Plague Cases--Letter of Warning and Appeal for Coöperation--Bacteriologic Observations made During the Manila Plague Epidemic, by Dr. Otto Schöbl--Notes Concerning the Bubonic Plague in Hong Kong, by Dr. David Roberg. CHAPTER IV ITS DIAGNOSIS AND TREATMENT 165 Biologic Diagnosis--Necessity for Trained Bacteriologist--Bacteriologic Procedure--Non-Biologic Diagnosis--Symptomatology--Pathologic Considerations--Treatment, Conditions and Prognosis--Serum Treatment--Symptomatic Treatment--Statistical Studies in Mortality--Dosage and Technique of Serum Administration--Prophylactic Serum and Anaphylaxis--Plague Vaccines. ILLUSTRATIONS PAGE RAT-PROOF STRUCTURE 48 CLEANING AND RAT-PROOFING IN BASEMENT 69 BAMBOO HOUSE SUPPORTS NOT SEALED WITH CEMENT 86 MATERIALS MUST BE MOVED ABOUT IN THE SEARCH FOR RATS 93 A RAT-INFESTED PLAGUE INTERIOR 95 PROGRESSIVE POST-MORTEM CHANGES IN RAT CADAVERS 105 PLAGUE HOUSE 116 BAMBOO HOUSE SUPPORTS SEALED WITH CEMENT 119 VIEW OF HOUSE WHERE INFECTED RATS WERE FOUND 120 ANIMAL HOUSE 144 PLAGUE ITS CAUSE AND THE MANNER OF ITS EXTENSION--ITS MENACE--ITS CONTROL AND SUPPRESSION--ITS DIAGNOSIS AND TREATMENT INTRODUCTION The question of the need for new books upon medical topics must ever remain undecided, by general agreement, in the medical profession.