Astronomical and Nautical Colteclwv Wt 



Young's theorem, and as obtained from his own very accurate ex- 

 perimental determination, both by the horizontal and the dipping 

 needle. 



Exper. Cowtput 



At St. Thomas 1-045 1*005 



Ascension 102 1-01 



Bahia 1-02 T04 



Sierra Leone 1*19 1*15 



Maranham 1-16 1*18 



Gambia 1-28 1*24 



PortPraya 133 1*31 



Teneriffe 1-49 1*45 



Trinidad 1-39 147 



Madeira 1*55 1'52 



London 1*62 1-62 



Jamaica 1-62 1*63 



Cayman ; . . 1-63 1*65 



Drontheim 1*64 1*67 



Hammerfest 1*69 1*68 



Havannah 1*72 1-71 



Spitsbergen 1*78 1*78 



Greenland 1*75 1*85 



New York Td9 Til 



Shetland 1-70 1*70 



Davis Strait (a) .... 194 1*95 



Hare Island 1*94 1'95 



Davis Strait (6) .... 1*98 1-97 



Baffin's Sea (a) .... 1-90 194 



Baffin's Sea (b) 1-92 1-94 



Baffin's Sea (c) 1-98 1-94 



Baffin's Sea (d) I -99 1-94 



Davis Strait (c) 1*98 1-98 



Possession Bay 1.95 1*96 



Regent's Inlet T96 1*96 



Byam Martin's Island . . 1*93 1-93 



Melville Island 1*92 1-92 



Winter Harbour .... 1*90 1*92 



The greatest variation of the experiment from the computation 

 is less than a seventeenth of the whole ; an agreement perfectly un- 

 expected in an approximation exposed to so great irregularity. Dr. 



