ON SEISMOLOGICAL INVESTIGATIONS. 69 
Harmonic expressions 
from P + 2-:1+ 2-7 cos (A — 207°) + 3-6 cos 2 (A — 73°) 
from S + 0:5 + 11-0 cos (A — 235°) + 2-6 cos 2 (A — 160°) 
Azimuth of Pulkovo being 342°, the mean direction of displacement 
(azimuth 220° say) is nearly at right angles to the direction of Pulkovo, 
and cannot be wholly explained by an error of tables. The small com- 
ponent in the line joining epicentre to Pulkovo is in the opposite direction 
to that previously noted. 
1913, June 14. Epicentre 43° N., 26° E., distant 17° from Pulkovo. 
There are unfortunately no observations of 8 from azimuth 90° to 
270°, so that we cannot make any analysis. The mean results for the 
other azimuths are 
Azimuth 270°—300°—330°—0°—30°—60°—90° 
Mean +1 —4 —2 —4 +4 0 
No observations 4 4 11 2 of ll 
which suggest a displacement in the opposite direction to that of January 11 
and March 14, and in the same direction as the component of April 30. 
The numbers for P are 
ae 20” Over OF Ae oy Ale 2 
and the harmonic expression is 
+ 2-1 + 2-8 cos (9 — 165°) + 1-6 cos 2 (6 — 111°) 
The azimuth of Pulkovo being 7°, the small displacement indicated is 
nearly radial and in the opposite direction to those of January 11 and 
March 14. 
Hence, so far as this evidence goes, the error of S—P is about 30 s. at 
85°, diminishes at lesser distances, and changes to a small negative value. 
The corrections needed by the Galitzin tables would seem to be approxi- 
mately as follows :— 
BS lor abr abr rn45ot) Sao Gh > Tbee (Sar, 1:957)1057 
s. Ss. Ss. Ss. 5. Ss. s. Ss. s. s. 
Correction P= 0 0 0.6 0 —1 —3 ~—8 —15 —24 
Correction S=4+5 0 —4 -—8 -—11 —14 —17 —24 —35 —50 
Correction (S-P) =+5 0 -4 —8'—11 —13 —14 —16 —20 —26 
Correction A=-—5 O +6 +13 +18 +24 +28 +31 +42 +52 
the correction to A being expressed in units of 0°'1. 
Investigation of the Upper Atmosphere.—Thirteenth Report of 
the Committee, consisting of Dr. W. N. SHaw (Chairman), 
Mr. E. Goup (Secretary), Messrs. C. J. P. Cave and W. H. 
Dines, Dr. R. T. GuazepRook, Sir J. LARmMor, Professor 
J. KH. PeTAvEL, Dr. A. ScHUSTER, and Dr. W. WATSON. 
A mretrina of the Joint Committee was held in the rooms of the Royal 
Meteorological Society on May 5, 1914. It was decided to allocate the 
grant from the British Association towards the expense of investigations 
with pilot balloons over the ocean to be undertaken by the Secretary 
on the journey to Australia, via the Cape of Good Hope. An 
