218с

1930г

PHOTOELECTRIC CELLS

THEIR PROPERTIES, USE, AND APPLICATIONS

BY ^

NORMAN ROBERT CAMPBELL

and

DOROTHY RITCHIE

members op the research staff of the general electric company ltd., wembley

SECOND EDITION

LONDON

SIR ISAAC PITMAN & SONS, LTD. PARKER STREET, KINGSWAY, W.C.2

BATH, MELBOURNE, TORONTO, NEW YORK 1930

ex.