[Illustration: (Frontispiece) Jack experienced an odd thrill as he
prepared to send the first spoken word ever exchanged between an
airship and land--_Page_ 71.]

THE
BOY INVENTORS' RADIO-
TELEPHONE

BY

RICHARD BONNER

AUTHOR OF "THE BOY INVENTORS' WIRELESS TRIUMPH," "THE BOY
INVENTORS AND THE VANISHING GUN," "THE BOY INVENTORS'
DIVING TORPEDO BOAT," "THE BOY INVENTORS' FLYING
SHIP," "THE BOY INVENTORS' ELECTRIC
HYDROAEROPLANE," ETC., ETC.

_WITH ILLUSTRATIONS BY_
_CHARLES L. WRENN_

NEW YORK
HURST & COMPANY
PUBLISHERS

CONTENTS

CHAPTER

I. THE POWER OF THE AIR