Terrestrial Magnetism. 165 
TABLE I1—Containing Observations of the positions of the Common and Coun- 
terpoised Needle, taken in the Philosophy School of Trinity College. 
i October 22. Therm. =56}° October 23. Therm.=57° 
3 io E marked side W E marked side Ww 
go4 SSS PS a a ae 
She | N Ss N Ss N Ss N s 
71° 20 «712 20 «| 71° 18 71° 20 «{ 71° 1s 71° 7 «| 71° 1s 71° 22 
E 
Sf | a0 70 30 | 70 25 70 30 |70 8 70 30 |70 35 70 30 | 
a i Re 22 | 71 15 71 ee ee) ee 
£/° wl 70 35 70 30 | 70 50 70 50 |70 35 70 25 |70 30 70 15 | 
Mean | 70 57.5 70 55.5 | 70 56.2 71 0.5 /70 55 70 50.5 | 70 53.8 70 53 
Final mean=70° 57'.4 Final mean=70° 53'.1 ip 
a v9 E marked side Ww E marked side Ww 
5 25 Se ee SS aes = ee ee 
3 (= e5)| eis s N s N s N s 
=| = |—27° 52° ~27° 52’ | —29° 20'29° 29’ |_12° 30” 12° 29° | 14° 15'—14° 30’ 
ie oe —28 45 —28 45 | —28 52-28 52 |-13 387 —13 37 | —-15 55-15 50 
a ,|F16ulS +16 15 | +20 15420 25 426 7 +26 15 | 429 35429 45 
a uf +15 15 +15 15 | +19 0+19 0 |+26 0 +26 0 | +30 10+30 10 
Mean Qe 25 An OT = ao ADS | 6'= —14° 4.5 6’ = +28° 0.2 
Calculated dip = 71° 22'.5 | Calculated dip = 71° 6’ 
(1) October 24. Therm. =58}° (2) October 24, Therm.=59° 
3 3A E marked side Ww E marked side w 
a 5-5) ——A~A—~ oN ae aa ait ae 
id ee s N s N s N s 
pijZede 71222, [7197 71° ger | 71° OF 7° IF | 71° lo” 7io oR 
“ i 70 40 70 30 | 70 30 70 22 |70 45 70 45 | 70 30 70 
8 FW AAG PO NAL 9) Fy The (| 7120) 71.40 (71, % 71 do.” 
S ie 70 35. 70 25 {70 30 70 30 |70 35 70 30 | 70 35 70 30 
“\Mean | 70 56.2 70 54.2 | 70 48.5 70 52.2|70 55 71 2.5 | 70 50.5 70 56,2 
Final mean=70° 52’.8 Final mean=70° 56’ 
3 %.0 E marked side Ww E marked side Ww 
EZ: fi A a a 
mis} Ae) oN s N s N s N s 
+ g |—35° 30 —85° 45° | —38° 10 —38° 15 |~10° 457 —10° 40° | —12° 457—12° 45° 
5 a —38 7 —38 0 |—39 55—39 55 |-12 45 -12 45 |-14 0-14 0 
a p|+6 35 +6 37 [+8 45+ 850 |+26 30 +26 30 | +30 30+30 30 | 
nf lea 15 +4 20 |+ 6 304 630/427 0 +27 0 | +30 30430 30 
Mean, = — 87? 57 o" = + 6 32/8 = — 12° 33 On = 428° 27.5 || 
Calculated dip = 70° 39’ | Calculated dip = 70° 56’ ! 
VOL. XVII. 2s 
