404 
MR. CHRISTIE ON THE MAGNETICAL OBSERVATIONS 
In the experiments with Hansteen’s cylindrical needle No. 3, that needle occupied 
the same position which the lozenge-needle had previously in the last set, the experi- 
ments with the two needles immediately following each other. The results obtained 
with this needle are given in the two following Tables : 
Trial-needle un- 
influenced. 
Trial-needle under the influence 
First ob- 
Last ob- 
of the needle No. 3. 
servation. 
servation. 
Beginning {xherm[ N." 1 ! ! ! 
60-0 
61-6 
47*6 
61-1 
76°-4 
62-0 
48-0 
60-2 
Time of 100 vibrations . . . . 
147-8 
147-7 
147*8 
147-9 
205-8 
205-6 
o o 
G4 G* 
205-7 
205-9 
r f Therm. 3 
49-0 
75°-0 
62-4 
50°-0 
Ending.. | Therm- N 
59-2 
61-2 
6l-2 
61-0 
t. r f Therm. 3 
48-3 
75-7 
62-2 
49-0 
60-6 
4 Therm. N 
59-6 
6 1 -4 
61-15 
Mean time of one vibration . . 
1-478 
2-057 
2-042 
2-058 
Therm. 3. 
Differences. 
Therm. N. 
Values of 
m 
lr 
Differences. 
Difference in 
value of ~ 
corresponding 
to difference of 
1° in Therm. 3. 
48°-3 
75-7 
49-0 
o 
27-4 
26-7 
6 1°- 1 5 
62-2 
60-6 
•4837261 
•4761133 
•4842278 
•0076128 
•0081145 
•0002778 
•0003039 
Mean. . . . 
•0002909 
Adopting similar methods of reduction to the preceding, from these results we ob- 
tain, for the correction of the observations made with the needle No. 3, the equation 
1 = I + •0000052 6 ( 1 ^‘ 3 ') 
The needle No. 3 being removed, its place was occupied by the needle No. 1, with 
which the following results were obtained : 
Trial -needle unin- 
fluenced. 
Trial -needle under the influence 
of the needle No. 1. 
First ob- 
Last ob- 
servation. 
servation. 
Beginning < 
Therm. 1 
45-4 
79-0 
46-0 
Therm. N. .... 
60-0 
61-6 
60-0 
60-8 
60-6 
Time of 100 vibrations .... | 
147-8 
147-7 
147-8 
147-9 
202-4 
202-3 
200-1 
200-3 
201-9 
201-9 
Ending . . - 
f Therm. 1 
47*0 
77°-0 
49 -0 
Therm. N 
59-2 
61-2 
60-0 
62-0 
61-0 
Mean. . . . < 
f Therm. 1 
46-2 
78-0 
47-5 
Therm. N 
59-6 
61-4 
60-0 
61-4 
60-8 
Mean Time of one vibration. . 
1-478 
2-0235 
2 S -002 
2-019 
