52^ CAPTAIN SABINE ON THE DIP OF THE 



level, and the mode of observation was the same in every particular. The needle 

 was fitted with a screw and weights, on Professor Meyer's plan. 



r«T 1 J J TVT D 1 rW. below; 52° 05'.5^ 



Exp. X. J M^^^^d ^^^ ^ ^- ^"^'- 1 W. above ; 89 38 .0 L- ^^.^^, 



Auff 18 i ^^ , J J c u 1 fW. below; 56 11.9 (^'1^ ^^ "^ 

 A"g- (^ Marked end a S. Pole. | ^ ^^^^^ .' gg jg 3 J 



r,^ 1 J J c Ti 1 fW. below; 62 24.0•^ 

 Exp. XI. \^^'^'^ '"'^ ^ ^' ^"^'- i W. above ; 77 54 .0 L. ,g ^^ 



Auff 19 1 ,* 1 J J XT u 1 fW. below; 62 19.0 ("^^ ^^ ^^ 

 A'^g- 19- (_Marked end a N. Pole. | ^ ^^^^^ ; ^^ ^^ J 



r»;r 1 J J XT 15 1 rW. below; 63 57.5 

 j^ J Marked end a N. Pole. | ^ ^^^^^ . ^^ 



a4.19- |MarkedendaS.Pole. { ^: ^vT I 78 22 .5 



Exp. XII. J ^^'•'^^^ ^"^ " ^- ^"'^- 1 W. above ; ^ 46 .0 U- .^ 33 



W. below ; 63 42 .0 

 W. above ; 78 22 .5 



f W. below ; 55 39 .0 



}■ 



r-KM 1 J J c Ti 1 J VV. below; 55 39.0^ 



Exp. XIII. J ^^'^^^ ^"^ ^ ^' P^^^' 1 W. above ; 87 30 .0 L. .. 0, ^ 



Auff. 20. 1 Tv^ , . ^ XT D 1 r W. below ; 53 32 .0 { ^ 



Aug. (^ Marked end a N. Pole. | ^ ^^^^^ . ^^ ^g J 



Mean . . . 69 51 .4 



The several results which have been enumerated, being collected in one 

 view, are as follows : 



Instrument of 12 inches diameter. Observer, Captain Sabine. 



Exp. I, II, & III, with a common needle 69°46'.l 



Exp. IV, V, VI, & VII, with Meyer's needle 69 47 .4 



Exp. VIII, with a needle having an adjustable axis . . 69 38 .3 

 Exp. IX, with Mr. Doux)nd's needle 69 51 .7 



Instrument of 6 inches diameter. Observer, Mr. Douglas. 

 Exp. X, XI, XII, & XIII, with Meyer's needle .... 69°51'.4 



Mean . . . 6 9 47 .0 



Whence the final result of the dip in the Horticultural Garden at Chiswick, 

 in August 1828, is 69° 47' North. 



The result of the observations in August 1821 was 70° 04'.5 (Phil. Trans. 

 1822 : Art. I.) ; whence the dip in London appears to have diminished 17'.5 in 



