EARTHQUAKES. 169 



black smoke (as was the case for several days in the rock of 

 Alvidras, during the earthquake of Lisbon, on the 1st No- 

 vember, 1755), flames of fire, sand, mud, and moyas, mixed 

 with charcoal, rise from fissures at a distance from all vol- 

 canoes. The acute geognosist, Abich, has proved the con- 

 nection which exists in the Persian Ghilan between the 

 thermal springs of Sarcin (5051 feet), on the road from Ar- 

 debil to Tabriz, and the earthquakes which frequently visit 

 the elevated districts in every second year. In October, 

 1848, an undulatory movement of the earth, which lasted 

 for a whole hour, compelled the inhabitants of Ardebil to 

 abandon the town ; and the temperature of the springs, 

 which is between 44° and 46° C. ( = 111°- 115° F.), rose 

 immediately to a most painful scalding heat, and continued 

 so for a whole month.* As Abich says, nowhere, perhaps, 

 upon the face of the earth is "the intimate connection of 

 fissure-producing earthquakes, with the phenomena of mud 

 volcanoes, of salses, of combustible gases penetrating through 

 the perforated soil, and of petroleum springs, more distinctly 

 expressed or more clearly recognizable, than in the south- 

 eastern extremity of the Caucasus, between Schemacha. 

 Baku, and Sallian. It is the part of the great Aralo-Cas- 

 pian basin, in which the earth is most frequently shaken." f 

 I was myself struck with the remarkable fact that in North- 

 ern Asia the circle of commotion, the centre of which ap- 

 pears to be in the vicinity of Lake Baikal, extends west- 

 ward only to the eastern borders of the Russian Altai, as 

 far as the silver mines of Riddersk, the trachytic rock of 

 Kruglaia Sopka, and the hot springs of Rachmanowka and 

 Arachan, but not to the Ural chain. Further, toward the 



* Abich, on Daghestan, Schagdagh, and Ghilan, in Poggend., An- 

 nalen, bd. Ixxvi., 1849, p. 157. The salt spring in a well near Sas- 

 sendorf, in Westphalia (in the district of Amsberg), also increased 

 about H per cent, in amount of saline matter, in consequence of the 

 widely-extended earthquake of the 29th July, 1846, the centre of 

 commotion of which is placed at St. Goar, on the Rhine ; this was 

 probably because other fissures of supply had opened (Noggerath, Das 

 Erdbeben im Rhehigebiete vorn 29 Juli, 1846, p. 14). According to 

 Charpentier's observation, the temperature of the sulphureous spring 

 of Lavey (above St. Maurice, on the bank of the Ehone) rose from 

 87°*8 to 97' -3 F. during the Swiss earthquake of the 25th August, 

 1851. 



t At Schemacha (elevation 2393 feet), one of the numerous mete- 

 orological stations founded by Prince Woronzow, in the Caucasus, 

 under Abich's directions, eighteen earthquakes were recorded by the 

 observer in the journal in 1848 alone. 



Vol. V.— H 



