ON THE FACTS AND THEORY OF EARTHQUAKE PHENOMENA. 19 
fewer than the known seismic character of the region warrants, and rightly 
attributes this to want of record, and to the want of communication in these 
parts of the world. He also remarks (what has been pointed out in the Second 
Report as applying to Antioch, &c.) that here seismic energy appears to have 
been in various localities extremely paroxysmal in its action, with long periods 
of intermediate cessation. In the Turco-Greek peninsula, earthquakes have 
long been both frequent and formidable. 
For the four critical periods of the year he finds 
Winter Solstice ...... Se ee 73 
SMe LOUUD Ks a io pp05 ead! nine § 61 
Summer Solstice 2... i. 005+ saneac. 10 
Autumnal Equinox ....,......... 74 
Pouqueville (‘ Voyage en Gréce’) has given some very singular facts and 
speculations as to the time of year of earthquakes in Epirus, &c., in re- 
lation to the rains. They need inquiry and confirmation. 
In analysing the horizontal direction of shock, Perrey has deemed it 
proper to separate the region under three sub-districts, in consequence of 
the broken character of the Greek peninsula, and the very diverse orientation 
of the coasts, river-courses, and mountain-ranges throughout all its parts. 
iatic. . 
Directions. Re sat e4 mate, Constantinople. Smyrna. Total. 
2 2 he 
W. to E. Med 
N.W. to S.E. ... 
m 
e+ 
° 
Zz 
We Repl 
— 
I 
These figures are meagre enough. By the usual method, Perrey calculates 
a mean general horizontal direction of shock, 
N. 34° 37! W. to S. 34° 37! E, 
_ The deduction, however, is plainly in this instance of little value. Many 
shocks in this region have been described as approximating to vertical; and 
this is to be anticipated from one having a centre of disturbance almost in 
its midst with active volcanic action. All its eastern end, Syria, &c., how- 
ever, has some separate centre of disturbance, either in connexion with the 
eastern chains of Asia Minor, which appear to abound in igneous forma- 
tions or with the Southern Arabian centre ; while Constantinople, the Dar- 
danelles, and the western and southern shores of the Euxine may also be in 
connexion with the Caucasian centre of action. 
We have now completed Perrey’s European series. He passes to the 
American by the discussion of the basin of the Atlantic, viewed as com- 
prehending all from Iceland on the north to ‘Tristan d’Acunha on the south, 
and on the east and west everything between the shores of the continents of 
the New and Old Worlds. 
Within this oceanic expanse no less than five great and probably con- 
nected centres of volcanic action exist: Iceland, the Azores, the Canaries, 
‘ * Including once for Aleppo. tT Including once for Latakia, 
{ Including once for Thassis. 
cQ2 
