HARPER & BROTHERS PUBLISHERS
NEW YORK AND LONDON


On Secret Service
Copyright, 1921, by Harper & Brothers
Printed in the United States of America

CONTENTS

PAGE
I.[A Flash in the Night]1
II.[The Mint Mystery]15
III.[The Ypiranga Case]28
IV.[The Clue on Shelf 45]42
V.[Phyllis Dodge, Smuggler Extraordinary]57
VI.[A Matter of Record]73
VII.[The Secret Still]88
VIII.[The Taxicab Tangle]103
IX.[A Match for the Government]118
X.[The Girl at the Switchboard]133
XI.["Lost—$100,000!"]149
XII.["The Double Code"]164
XIII.[The Trail of the White Mice]180
XIV.[Wah Lee and the Flower of Heaven]195
XV.[The Man with Three Wives]210
XVI.[After Seven Years]225
XVII.[The Poison-pen Puzzle]239
XVIII.[Thirty Thousand Yards of Silk]254
XIX.[The Clue in the Classified Column]268
XX.[In the Shadow of the Capitol]283
XXI.[A Million-dollar Quarter]298
XXII.["The Looting of the C. T. C."]313
XXIII.[The Case of Mrs. Armitage]328
XXIV.[Five Inches of Death]343

ON SECRET SERVICE