[NoveMBER, 1903. ] 
THE 
SCIENTIFIC TRANSACTIONS 
OF THE 
RONAIL JIDUIBIGIIN S\OrrmDahae 
VOLUME VIIL—(SERIES II.) 
IY. 
IONIZATION IN ATMOSPHERIC AIR. 
BY 
J. A. McCLELLAND, M.A., 
Professor of Experimental Physics, University College, Dublin. 
DUBLIN: 
PUBLISHED BY THE ROYAL DUBLIN SOCIETY. 
WILLIAMS AND NORGATE, 
14, HENRIETTA STREET, COVENT GARDEN, LONDON ; 
20, SOUTH FREDERICK STREET, EDINBURGH; anp 7, BROAD STREET, OXFORD. 
PRINTED AT THE UNIVERSITY PRESS, BY PONSONBY AND GIBBS. 
1908. 
