[May, 1902.] 



THE 



SCIENTIFIC TRANSACTIONS 



ROYAL DUBLIN SOCIETY. 



VOLUME VII.— (SERIES II.) 



XV. 



SOME NEW FOEMS OF GEODETIC AL INSTRUMENTS. 



BY 



SIE HOWARD GRUBB, F.R.S., 



Vice-Pres. Royal Dublin Society. 



(Plate XXXIV.) 



DUBLIN: 



PUBLISHED BY THE ROYAL DUBLIN SOCIETY. 



WILLIAMS AND NORGATE, 



14, HENRIETTA STREET, COVENT GARDEN, LONDON ; 



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



PRINTED AT THE UNIVERSITY PRESS, BY PONSONBY AND WELDRICK. 



1902. 



