348 Professor Bischof on the Origin of 
change in the nature of the spring’s deposit. In the imme- 
diate vicinity of the iron springs, more or less considerable 
deposits of calcsinter present themselves, whilst the actual 
or present sediments consist of iron-ochre, with a slight ad- 
mixture of lime. It is very probable that these are the 
very springs which formerly deposited calesinter, and which, 
at the present day, deposit only iron-ochre. If such a change 
in the nature of the spring’s deposit be in harmony with the 
not unfrequent change in the constituents of the spring, we 
have in this an indication of the various deposits which occur 
in vein clefts—viz. in metalliferous veins. I believe, in fact, 
to have acquired conviction, and hope to shew proofs, that 
the most of the vein stuffs in metalliferous veins, if not all, 
have been introduced in the wet way. 
Evidence for the variety of deposits in metalliferous veins 
are presented, amongst others, by the veins of the Erzgebirge. 
Thus, v. Weissenbach found, in the silver veins of Brand, 
in the Freyberg district, the arrangement of the component 
parts of the vein from the older towards the younger mem- 
bers—that is, from the wall to the centre, to be always as 
follows :— 
1. Quartz predominating. 
2. Manganese-spar—Brown-spar. 
3. Sparry iron, fluorspar, barytes, equal with each other. 
4. Calespar. 
He never found the above-named sparry minerals in any 
other than this series, and it appears, as far as he had op- 
portunity of observing, to occur pretty much the same 
throughout the whole Saxon vein formation. It is import- 
ant in reference to this mode of formation of the vein mass 
in metalliferous veins, remarks v. Weissenbach, that, should 
the above observation obtain generally, it would result 
that not the ores, but much more the kinds of spar, would, 
to a certain degree, characterize the epochs of formation.* 
* Just as I was about to send off this paper, I have received, through 
the kindness of the Berghauptmann Freiesleben, his most recent inter- 
esting work, ‘‘ Die Sachsische Erzginge,”’ &c., &c. Freyberg, 1843. 
We there find under the title, “‘ Arrangement of the Vein stuffs,” 
the following: ‘It is peculiar to many formations, as has been long 
