[November, 1899.] 



THE 



SCIENTIFIC TRANSACTIONS 



ROYAL DUBLIN SOCIETY. 



VOLUME VIL— (SERIES 11.) 



III. 



AN ESTIMATE OF THE GEOLOGICAL AGE OP THE EAETH. 



By J. JOLY, M.A., D.Sc, F.R.S., 



Honorary Secretary of the Eoyal Dublin Society ; 



Professoor of Geology and Mineralogy in the University of Dublin. 



DUBLIN: 



PUBLISHED BY THE EOYAL DUBLIN SOCIETY. 



WILLIAMS AND NOKGATE, 



14, HENRIETTA STREET, COVENT GARDEN, LONDON , 



20, SOUTH FEEDEEICK STREET, EDINBURGH; and 7, BROAD STREET, OXFORD. 



PRINTED AT THE TJNIYEESITY PEESS, BY PONSONBY AND WELDRICK. 



1899. 



Price One Shilling and Sixpence. 



