THE GASES

OF

THE ATMOSPHERE

THE

HISTORY OF THEIR DISCOVERY

BY

SIR WILLIAM RAMSAY, K.C.B., F.R.S.

OFFICIER DE LA LEGION D'HONNEUR

EMERITUS PROFESSOR OF CHEMISTRY IN UNIVERSITY COLLEGE, LONDON

FOURTH EDITION

WITH PORTRAITS

MACMILLAN AND CO., LIMITED

ST. MARTIN'S STREET, LONDON

1915