50 CAPTAIN SABINE ON THE DIP OF THE 



August 16th. 3 to 5 P.M. Therm. 66°. 



Time of Vib". 



(Marked end a N.Pole 54^0 ^w. above; 87 11.2 U- .^o.^,^ 



^"P- ^- -^ ^ W . S Pnl. .. 6 /W. below; 58 55.2 P^? ^^ ^^ .0 

 ( Marked end a S. Pole 53 .6 <|^^ ^^^^^^ . g^ g^, g j 



August 20th. Noon to 2 P.M. Therm. 68°. 



r^f ^ A A « u^io r;osfi /W.below; 57°28'.7^ 

 j Marked end a S. Pole 53'.6 |^ ^^ g^ 33 ^ I 



Exp. VI. <^ rw below 52 48.3 P'P ^^ ^^'^ 



[Marked end a N. Pole 52 .8 \y^\ ^^^^^ .' gg jg g J 



August 20th. 4 to 5 P.M. Therm. 67°. 



r^^ ^ A , XT T) 1 rW. below; 52° 06'.0-\ 



f Marked end a N. Pole \ ^ ^ ; 89 51 .0 I ^. , .^ .^ ^ 



Exp.VII.<^ rw below- 57 12 T^'i^ ^^ ^^'^ 



(^ Marked end a S. Pole |^; ^^^^^ ; gg ^3 ;() J 



Mean . . . 69 47.4 



With the same general apparatus I employed also two other needles : one a 

 flat needle with a cross of wires attached to the axis, two in the longitudinal 

 direction of the needle, and two at right angles to it. By means of small 

 weights sliding on these wires, the axis could be brought very nearly, if not 

 exactly, to coincide with the centre of gravity. The same number of obser- 

 vations were made with this needle, and in the same general manner as in the 

 experiments numbered I, II, and III. The following is the result obtained. 



August 20th. 2 to 4 P.M. Therm. 69°. 



T7 TrTTT r Marked end a N. Pole 24 Readings 69°34'.25 ") j.. „„o„«, o 

 ■S^'P": I Marked end a S. Pole 24 Readings 69 42 .35 ] ^^P ^^ ^^ "^ 



The other needle was on a plan proposed some time ago by Mr. Dollond. 

 The two ends of this needle are conical ; the bases of the cones occupy two 

 sides of a cube, which forms the middle of the needle ; the other four sides 

 being perforated for the purpose of receiving the axis in eveiy direction. These 

 sides are numbered for distinction 0, 1, 2, 3 ; being opposite to 2, and 1 to 3. 

 The axis is passed through the perforation until a shoulder on the one arm of 

 the axis blocks against one of the sides of the cube, for example : a nut is 

 then screwed on the other arm of the axis against the side 2, until the axis is 

 tightened in its place, care being taken that the same parts of the axis coincide 



