402 
MR, CHRISTIE ON THE MAGNETICAL OBSERVATIONS 
Trial-needle under the influence 
of the Lozenge-needle. 
Trial-needle | 
uninfluenced. | 
Beginning ■ 
f Therm. L 
[Therm. N 
46-0 
64-6 
79° 4 
68-0 
46-0 
65-0 
63-0 
Time of 100 vibrations. . . . ^ 
174-9 
174-8 
174-4 
174-4 
174-6 
174-8 
147-4 
147-6 
Ending. . < 
r Therm. L 
Therm. N. 
48-0 
66-0 
7 7° 4 
66-0 
47° 6 
66-0 
67-6 
Mean . . < 
[Therm. L 
47-0 
78-4 
46-8 
Therm. N. 
65-3 
67-0 
1*744 
65-5 
65-3 
Mean time of one vibration . . 
1-7485 
1-747 
S 
1-475 
The observations commenced at 7 h 8 m p.m., and concluded at 8 h 45'” p.m. 5th March. 
Finding’ that in this position of the lozenge-needle the times of vibration of the 
trial-needle were so little affected by changes in the temperature of the former that a 
small error in these times would materially affect the results, I made a second set of 
observations, in which the lozenge-needle was raised '84 inch, its distance from the 
trial-needle being reduced to 3'06 inches. The following Table contains the results 
of this set : 
Trial-needle un- 
influenced. 
First 
observation. 
Last 
observation, 
Trial-needle under the influence 
of the Lozenge-needle. 
Beginning ^ 
Therm. L. 
Therm. N. 
Time of 100 vibrations 
....{ 
t-. f Therm. L. . 
Ending.. | Therm<N _ 
Mean 
/ Therm. L 
[Therm. N 
Mean time of one vibration . . 
60-0 
1 47*8 
147-7 
59-2 
59-6 
61-6 
147*8 
147-9 
61-2 
61-4 
1-478 
46- 8 
59- 6 
216-8 
217-2 
48*4 
60 - 0 
47- 6 
59-8 
2U70 
80-0 
60-0 
215-4 
215-4 
77°-0 
6i-0 
78-5 
60-5 
2-154 
49- 0 
60-0 
216-8 
216-3 
50- 2 
60-2 
49-6 
60-1 
2-1655 
Note . — The first observation with the trial-needle uninfluenced commenced at 0 11 5 m p.m.; then followed 
the observations with that needle under the influence ; 1st, of the lozenge-needle ; 2nd, of needle No. 3 ; 
3rd, of needle No. 1; and the last observation with the trial-needle uninfluenced concluded at 4 h 50'" p.m 
6th March. 
Substituting the times of vibration in the first set of observations in the equation 
(16.), we have the following results : 
