AND SEMI-ANNUAL SEISMIC PERIODS. 
1129 
39. Sicily .—C. W. C. Fuchs, ‘ Statistik der Erdbeben,’ pp, 213-224. 
Duration of record, 1865-1883. Number of earthquakes, 324. 
The results, as pointed out above (§ 36), are not of great value, owing to the large 
number of shocks felt during Mai’ch, 1883.* 
Period. 
Maximum. 
Amplitude. 
Annual. 
May, h 
•67 
Semi-annual ...... 
J February, b 1 
\ August, b j 
•46 
Annual barometric. . . 
November, b 
40. It may be interesting to compare with these results the observations made by 
P. T. Bertelli on the relative microseismic intensity at Florence. These are sum¬ 
marized for the interval December, 1872, to November, 1887, in his paper, “ Delle 
variazioni dei valori dTntensita Tromometrica relativa osservata nel Collegio alia Querce 
di Firenze dell’ anno meteorico 1872-73 al 1886-87.” Observations were made with 
two tromometei'S which are termed the “old tromometer” and the “normal tromo¬ 
meter ”; with the first for the whole period of 15 years, and with the second for the 
last 11 years. 
(l.) Old tromometer, December, 1872-November, 1887. 61,732 observations. 
Period. 
Maximum. 
Amplitude. 
Annual. 
December, h 
•49 
Semi-annual . . . . | 
May, a —June, a 
November, a—December, a 
00 
p 
* If we omit this year we get the following results, which agree more closely with those obtained f]'om 
the Yesuvian district (the number of earthquakes being 242). 
Period. 
Maximum. 
Amplitude. 
Annual. 
.luly, b- 
•50 
Semi-annual. 
J June, 0 1 
\ December, b j 
•19 
7 E 
MDCCCXCIII. — A. 
