PRESIDENTIAL ADDRESSES. 



[Delivered at the Anniversary Meetings of tJie Royal Society, 

 of November, 30/7*, 1891, November 3O/ 1 //, 1892, and 

 November ^oth, 1893.] 



EXTRACT FROM ADDRESS OF NOVEMBER 

 30TH, 1891. 



A FUNDAMENTAL investigation in astronomy, of 

 great importance in respect to the primary obser- 

 vational work of astronomical observatories, and 

 of exceeding interest in connection with tidal, 

 meteorological, and geological observations and 

 speculations, has been definitely entered upon 

 during the past year, and has already given 

 substantial results of a most promising character. 

 The International Geodetic Union, at its last 

 .meeting in the autumn of 1890, on the motion 

 of Professor Foerster, of Berlin, resolved to send 



