1919.] 
Departmental Reports. 
i 
DEPARTMENTAL REPORTS. 
Magnetic Observatory, Christchurch. — Seismological 
Records. 
EARTHQUAKE RECORDS BY MILNE SEISMOGRAPH No. 16 FOR THE 
YEAR 1915. 
By H. F. Skey, B.Sc., Director of Observatory. 
(Communicated by the Surveyor-General.) 
Register from Magnetic Observatory, Christchurch, New Zealand. 
(Longitude, 11 h. 30 min. 29 sec. E. ; latitude, 43° 31-8' S.) 
Notes relating to preliminary tremors or first phase, Pi ; second phase, P 2 ; third phase 
or large waves, P 3 ; duration, D; amplitude, A. Time is Greenwich civil 
mean time. 0 h. or 24 h. = midnight. The boom period is generally maintained at 
16 seconds. 
No. 
Date. 
Commence¬ 
ment. 
Maximum. 
Maximum 
Amplitude. 
Duration. 
Remarks. 
1915. 
H. M. 
H. M. 
Mm. 
H. M. 
1 
Jan. 3 
0 03-9 
Pf 
0 06-8 
0 11 1 
5-0 
P 3 - 
• 
1 35 
D. 
2 
Jan. 5 
14 09-0 
. „ 
Pi- 
14 34-0 
. o 
, . 
P 2 . 
14 45 0 
14 49-9 
4-9 
P 3 - 
14 59-6 
• 9 
• . 
Pp 
1 00 
D. 
3 
Jan. 5 
23 39 0 
O O 
• . 
Pi- 
23 49-2 
23 50 0 
2-9 
P 2 - 
24 08-0 
2-8 
P 3 ; commencement uncertain. 
1 50 
D. 
4 
Jan. 10 
23 33 0 
. « 
Pi- 
23 34-5 
. • 
IV 
23 37-0 
23 41-3 
1-3 
P 3 . 
1 20 
D. 
5 
Feb. 25 
20 40-5 
• „ 
Pi- 
20 43-0 
P 2 * 
20 47-5 
20 48-1 
4-9 
P 3 . 
20 51-2 
20 53-5 
2-0 
Pi- 
1 55 
D. 
6 
April 25 
5 56-1 
. . 
Pi- 
5 57-0 
5 57-4 
1-2 
P 3 . Local shock. 
0 28 
D. 
7 
May 1 
5 13-5 
. . 
. • 
Pi- 
5 24-2 
. • 
. , 
P 2 . 
5 43-6 
5 57-0 
11-0 
Pa- 
6 + 
D. 
8 
May 3 
3 34-2 
e . 
. . 
Pi. 
4 28-6 
4 32-1 
12-0 
P 3 (P 2 indeterminate). 
3 10 
D. 
9 
May 5 
11 25-7 
. • 
• . 
Pi- 
11 36-2 
11 39*3 
7-2 
P 3 (P 2 indeterminate). 
11 42-9 
7-6 
Second maximum, interference. 
D indeterminate. 
