Transcriber’s Note: Words and phrases in italics are surrounded by _underscores_. MICROBE HUNTERS MICROBE HUNTERS _by_ PAUL DE KRUIF “The gods are frankly human, sharing in the weaknesses of mankind, yet not untouched with a halo of divine Romance.” E. H. BLAKENEY. [Illustration: (colophon)] _New York_ HARCOURT, BRACE AND COMPANY COPYRIGHT, 1926, BY HARCOURT, BRACE AND COMPANY, INC. PRINTED IN THE U. S. A. TO RHEA CONTENTS CHAPTER PAGE I LEEUWENHOEK: First of the Microbe Hunters 3 II SPALLANZANI: Microbes Must Have Parents! 25 III PASTEUR: Microbes Are a Menace! 57 IV KOCH: The Death Fighter 105 V PASTEUR: And the Mad Dog 145 VI ROUX AND BEHRING: Massacre the Guinea-Pigs 184 VII METCHNIKOFF: The Nice Phagocytes 207 VIII THEOBALD SMITH: Ticks and Texas Fever 234 IX BRUCE: Trail of the Tsetse 252 X ROSS VS. GRASSI: Malaria 278 XI WALTER REED: In the Interest of Science--and for Humanity! 311 XII PAUL EHRLICH: The Magic Bullet 334 INDEX 359 LIST OF ILLUSTRATIONS FACING PAGE ANTONY LEEUWENHOEK 16 LAZZARO SPALLANZANI 48 PASTEUR AT FORTY-FIVE 74 ROBERT KOCH 140 VACCINATING SHEEP FOR ANTHRAX 166 DR. ROUX 204 ÉLIE METCHNIKOFF 228 LAST PORTRAIT OF EHRLICH 354 MICROBE HUNTERS CHAPTER I LEEUWENHOEK FIRST OF THE MICROBE HUNTERS I