612 
PROFESSOR FORBES ON THE TEMPERATURES 
the thermometer rise to the boiling-point, but admits that after rain he found it lower. 
Della Torre gives it a temperature of 68° R. = 185° F. The Abbe Soulavie states 
it at 101° F., Humboldt* at 93° cent. = 199 0, 4 F. Hence there can hardly be a 
doubt that this spring is liable to great variations of temperature. 
1826, December 7- Exterior air, 41 0, 5. Interior of the hut, 70 o, 5. 
Cart. Reduced. 
Spring of La Pisciarella, hottest part .... 114 o, 0 112 o- 0 
Note . — The temperatures of the following springs I also measured ; and though I 
cannot speak so precisely as to the limits of error of the observations, they are un- 
doubtedly very small. 
1827, March 24. Hot spring behind the temple of Jupiter Serapis at Pozzuoli, 98 0, 5. 
March 28. Gurgitello, Ischia (taken in a sort of well, into which it rises), 149°. 
I shall conclude by recapitulating in a tabular form the final results obtained in 
this paper, and which it may be hoped are adapted for future reference as ascertained 
scientific facts-|~. I have much satisfaction in being able to subjoin, through the 
kindness of M. Arago, a series of unpublished observations which he made in 1826 
on several of the hot springs of France, by a thermometer whose indications are re- 
duced to the true scale;};. I have likewise placed for reference the observations of 
* Relation Historique, 4to, tom. ii. p. 86. note. Whether from his own observations I do not know, 
f The following tabular view of the concurrence of five classes of geological facts already alluded to in the 
Pyrenees may not be uninteresting : 
Place. 
Hot Springs. 
Neighbourhood 
of Granite. 
Fissures and 
Faults. 
Metamorphic 
Rocks. 
Metalliferous 
Veins. 
Eaux Chaudes 
* 
# 
* 
* 
* 
Eaux Bonnes . . 
* 
? 
* 
* 
Cauteretz .... 
* 
* 
* 
St. Sauveur . . 
* 
* 
* 
Bareges ...... 
* 
# 
J 
Bagneres .... 
* 
* 
Caudiac 
# 
B. de Luchon. . 
* 

? 
* 
Lez 
* 
* 
J 
Aulus 
Ussat 
? 
Ax 
* 
* 
Las Escaldas . . 
* 
* 
* 
Thuez 
* 
* 
*• 
Verne t 
Arles 
* 
* 
* 
The indications of metals are chiefly taken from Galabert, Carte Mindralogique des Pyrenees, 1831. 
I These observations are not accompanied by minute indications of the state of the springs, or the particular 
points at which they were made. 
