OBSERVATORIES AND THE DATA OBTAINED. 87 
Duration, 1.8 hours. The three Ehlert pendulums give very different effects. They all 
begin at closely the same time but the second group is well shown only on (2), the instru- 
ment which records the northeast movement, that is, at right angles to the direction of 
propagation; this indicates a transverse wave. It can be recognized on (1), recording 
the north-northwest component, at 38.3", but not so clearly. The beginning of the 
regular waves is not recognizable; nor can we be sure of the time of beginning of the 
principal part. 
The lines just below the seismograms are the records of a different hour. 
KRAKAU, AUSTRIA. 
K. K. Sternwarte, Prof. Dr. M. F. Rudski, director. 
Lat. 50° 04’ N.; long. 19° 58’ E.; altitude, 205 meters; distance, 85.98° or 9,558 km. ; 
chord, 8,687 km.; direction, N. 23° E. . 
Foundation, compact sandy clay alluvium. 
Seismograms, sheet No. 13. 
The instruments used were Bosch-Omori horizontal pendulums, two components; 
mechanical registration on smoked paper. 
(1) Northwest component: 79, 31.2 seconds; V, 10; J, 2,400 meters; e¢, 1.0 (?); 
fae, (2); MM, ii kes 0, 75 cm. 
(2) Northeast component: 7, 25.8 seconds; V, 9.6; J, 1,600 meters; e, 1.24 (?); 7, 
mee. (7); M, like: L, 75 em. 

SECOND 
PRELIMINARY 
TREMORS. 
REGULAR PRINCIPAL 
WAVES. Part. PERIOD, 

min, min. min. 
(1) Northwest component 35.8 54.5 Dae 
(2) Northeast component 35.6 53.6 58.0 
™m. 8. m, 8. m, 8. 
AVOYADGm se fe eo 35 42 54 06 ov 6383? 
Interyahiee nr.) <r.) 4. 23 #14 41 38 45 07? 






Duration, northwest, 2.3 hours; northeast, 1.8 hours. 
The beginning of the disturbance was not registered, tho very slight movements can be 
made out on the northwest component about 13" 27"; they are very slight and would 
not be recognized unless especially lookt for. The early motion (second preliminary 
tremors) is somewhat larger in the northwest than in the northeast component, indicating 
longitudinal waves; but this may be due to friction in the latter component. It is not 
entirely clear why the first preliminary tremors were not properly registered; the seismo- 
grams show that the northeast component had strong, solid friction which would be 
sufficient to prevent it from registering very small disturbances; but this condition is not 
so evident in the northwest component. 
Dr. Rudski only gives the times to tenths of minutes on account of the uncertainty of 
the beginning of the different phases; but the clock-time is perfect. The periods during 
the strong motion are so close to the natural periods of the pendulum that we can not 
make a good determination of the earth’s movement. The values of the damping ratios 
and the solid friction are determined from observations made long before the date of 
the earthquake. 
GRANADA, SPAIN. 
Observatorio de Cartuja. P.S. Navarro-Neumann, S. J., director. 
Lat. 37° 11’ N.; long. 3° 48’ W.; altitude, 776 meters; distance, 86.08° or 9.570 km. ; 
chord, 8,696 km.; direction, N. 44° E. 
Foundation, piers are directly on Tertiary limestone. 
Seismograms, sheet No. 14. 
