96 REPORT OF THE CALIFORNIA EARTHQUAKE COMMISSION. 
ROCCA DI PAPA, ITALY. 
R. Osservatorio Geodinamico. Prof. G. Agamennone, director. 
Lat. 41° 46’ N.; long. 12° 42’ E.; altitude, 760 meters; distance, 90.48° or 10,061 
km.; chord, 9,046 km.; direction, N. 32° E. 
Foundation, volcanic rock. 
Seismograms, sheet No. 14. 
The instruments used were: 
Microseismograph Agamennone, two components; mechanical registration with ink 
on white paper. 
(1) Northwest component: T,, 4.2 seconds; V,60; J, 264 meters; ¢, 1.0; r, 0.38 mm.; 
M, 500 kg.; L, 4.39 meters. 
(2) Northeast component: T,, 4.2 seconds; V, 60; J, 264 meters; ¢, 1.0; 7, 0.20 mm.; 
_M, 500 kg.; L, 4.389 meters. 
New microseismometrograph Agamennone (80 kg.), two components; mechanical 
registration on smoked paper. 
(3) North and (4) east components: T,, 2.6 seconds; V, 100; J, 168 meters; e, 1.0; 
r, 0.1 mm.; M, 80 kg.; LD, 1.68 meters. 
Cancani horizontal pendulums, two components; mechanical registration with ink 
on white paper. 
(5) North component: T,, 27.2 seconds; V,1; J, 185 meters; e, 1.03; 7, 0.0 mm.; 
M, 60 kg.; ZL, 1.00 meter (?). 
(6) East component: T,, 26.6 seconds; V, 1; J, 176 meters; e, 1.06; r, 0.0 mm.; 
M, 60 kg.; L’, 1.76 meters; L, 1.00 meter (?). 









S Eine 
PRELIMINARY Ge St ifoad bce Max. AmpuitupE,| Prrtop. Auruic 
Mie 78: m 8. m. 8. min mm sec. mm. 
(1) Northwest component] 36 15 56 257 aan as 07.3 3.2 19 1-15 
m. 8. 
(2) Northeast component| 36 57 57 25? |) 57 29 LO Malt 2.0 NZ 0.5 
(3) North component: )2)) 23) .- 57 50? | 06 OO 07 00 2.0 17 0.8 
(4) East component . .| 35 46 58. 1474, 037202) F Ovee30 2.0 ey 0.8 
(5) North component. .| 36 34 57 =50 59 15 05 20 12.5 26 
(6) East component . .| 37 00 Yh Ns) Ol 25 04 14 15.0 27 
AVerace on 210s Be 921) Apo ea0 57 «30 
Interval. seaeeere | e+e OS 45 02 



Duration, 2 hours. The beginning of the motion on all the instruments was masked 
by vibrations due to high winds. 
The seismograms are reproduced from tracings, which, in the case of the 80 kg. Aga- 
mennone seismograph, do not bring out the regularity and fineness of the original record 
on smoked paper. One sees, however, the short vibrations of the pendulum superposed 
on the larger earth vibrations. The greatest earth-amplitude was at 14” 07.3"; the 500 
kg. seismograph indicates an amplitude of 1.1 mm. in the northwest direction, and the 
two components of the 80 kg. instrument indicate: North, 0.82 mm.; east, 1.14 mm.; a 
total amplitude of about 1.4 mm. in the northwest or northeast direction. These instru- 
ments therefore partially confirm each other and indicate that the maximum motion was 
in the line of propagation. 
The Cancani horizontal pendulums have no damping; and since their natural periods 
correspond closely to those of the disturbance, no conclusion can be drawn from their 
record regarding the earth’s amplitude. 
