244 =Natural History of Volcanos and Earthquakes. 
77028 
=77028 inches of a column of mercury, or —3- =2751 atmos- 
pheres, and ate gives the same number. On the other hand, 
for a constant increase of temperature of 1° F. in 57.1 feet it ad- 
vances to a-depth of 105627 feet below the surface of the sea, 
where the corresponding temperature would be 1881°.5 F. ;* for 
the same formula gives e= 92435 inches of a column of mercury, 
105627 
or 3301 atmospheres, when ¢ =1881°.5, and 5 
same value. Presupposing the correctness of the premises, these 
aes 88044 
calculations shew the possibility of columns of lava te ec 
29348 and = =35209 feet being raised by the power of 
steam from the respective depths of 88044 and 105627 feet below 
the surface of the sea, whilst there is an uninterrupted communi- 
cation between the sea and the voleanic focus. The difficulty 
mentioned by Gay-Lussac, that the water would, under its own 
pressure, take the gaseous form before reaching the strata, which 
are at white heat; without being able to raise the lavas, to cause 
earthquakes, and to support the voleanic phenomena; is conse 
quently also set aside, in so far that the water cannot assume the 
form of gas under its own pressure before reaching those depths 
and their corresponding temperatures. At depths greater than 
88044 or 105627 feet below the surface of the sea, if the commu- 
nication with the sea remained free, a reaction would take place 
in the colamn of water. Perhaps the phenomena mentioned in 
Chap. xi, on Hot and Mineral Springs, vol. xxiii, of Ed. New 
Phil. Journal, and observed by Horner near the Kurile Islands, 
as well as the powerful stream of hot steam, observed by Holl- 
mann near Vulcano,t beneath the surface of the sea, probably at 
the same place where the crater of the cone formerly throw? up 
at this spot was situated, proceeds from a similar volcanic efler- 
vescence. In general, the rising of smoke from the sea during the 
eruptions of neighboring volcanos is by no means an uncommon 
occurrence.{ ‘The reflux and the internal agitation of the seals 
gives the 
* To simplify the calculation, I have supposed the mean temperature end 
surface = 32° F, oco cit. p. 67. “a 
¢ D. Curbetto (Von Buch loco cit. p. 78) observed a great quantity of smoke am 
flames (?) accompanied with tremendous detonations, rise from the sea - 
cerote, during the volcanic eruption on that island. Fish and pieces aa sat 
were seen floating about. Several examples of this sort are cited farther 0M 
