194 Dr. J. Neeggerath on the Volcanic 
produced by volcanic power, into which the chloride of so- 
dium has entered by sublimation. L. de Buch proves this in 
a highly convincing manner. Guided by that fact, and sup- 
ported by other grounds, he further supposes that the rock~ 
salt formations in the floetz strata very probably have also a 
voleanic origin. 
But I had already ventured to propose the same theory of 
rock-salt formations before the vein at Bex was known. ‘The 
merit of this I must indeed acknowledge is not great: having 
the advantage of L. de Buch’s work, it was easy for me to ad- 
vance.one step further than he had gone; or perhaps, I only 
expressed more definitely what L. de B. had long conceived, 
and was a simple consequence of his comprehensive observa~ 
tions. But since my theory has the concurrence of so valuable 
an experience as that of M.de Charpentier, it will not be wholly 
uninteresting to make my early expositions better known. 
In the collection of foreign works published by me and 
M. D. Pauls on volcanos and the phenomena allied to them, 
the second volume of which (containing the volcanos at Java, 
by Sir T. S. Raffles; the Monte-somma by L, A. Necker, and 
the volcanos in Auvergne, by Dr. Daubeny) had already been 
printed at the end of February 1825, I put in a note a Ger- 
man translation of Humboldt’s treatise concerning the ap- 
pearance of sulphur in the primary rocks, according to Gay- 
Lussac and Arago, (Annales de Chimie et de Phys. 1824, Oct.) 
and I added the following remarks of my own. 
«‘ The excellent communications of A. von Humboldt afford 
us not only decisive proofs of the existence of sulphur in the 
primary rocks, but render it very probable also that they con- 
tain great masses of it. To ascertain the origin of the sul- 
phur and its combinations in the fixed, fluid, and gaseous pro- 
ducts of voleanos has hence lost the greater part of its diffi- 
culties. If on the one hand collective experience, and the 
theories that have been most recently raised on it, tend to 
establish Von Humboldt’s remark (Ueber der Bau und the 
Wirkungen der Vulkane), that ¢ the powers of volcanos operate 
simultaneously, not superficially from the outer crust of the 
earth, but profoundly from the interior of our planet, through 
caverns and vacant passages, on its remotest points,’ the ex- 
istence of sulphur in the newer rocks, and especially in those 
that are formed in horizontal strata, cannot account for the im- 
portant part which this mineral (sulphur) performs in voJcanos. 
Von Przystanowski (Ueber den Ursprung der Vulkane in Italie 
1822) has indeed the merit of having indicated two great tracts 
in Italy, in which the sulphur (with iron-pyrites, sulphuret of 
antimony, asphaltum, anthracite, and rock-salt) is diffused in 
the 
