ST. LAWRENCE COUNTY, 
343 
the specular is uniformly the primary limestone; and though no one will question the possi¬ 
bility of the crystallization of tufa and marl, and the separation of the oxides which may have 
been originally mixed with them, still the opinion that this limestone was a marl or a tufa is 
a gratuitous assumption: there is no fact revealed, in connection with those masses, which 
goes to show that such was originally the state and condition of those substances. Now, in 
pursuing these masses, there has been always a descent into the primary rocks, showing clearly 
that there is no platform of deposit upon them, but that it is uniformly heloio or within them. 
It is true that the potsdam sandstone is often above these masses, and is often highly charged 
with the oxide of iron; but how does this happen ? Any porous rock, like this sandstone, 
would become thus charged when placed in contact with a substance of this kind, whether 
below or above. But in addition to the above facts, the rocks, both primary and transition, 
when connected with the specular ore, are broken and elevated ; and instead of the deposits 
of ore and of limestone in the form of marl on a smooth unbroken platform, they are always 
and without exception disrupted masses, and both the oxide and the calcareous rock descend 
downward into those primary rocks which are broken and fractured: there is therefore really 
no spreading out of the main mass of ore upon the upper surface of the primary, without also 
a descent downwards into a fissure or vein clearly into the primary masses, and in some in¬ 
stances the depth has not been ascertained. A reference to my sections of the Parish and 
Kearney ore beds (p, 93), will illustrate the position and relations of the specular ore. 
In the above remarks, I have spoken to two questions raised by Mr. Vanuxem’s opinions, 
rather than one : 1st, to the opinion that the present oxide, and the limestone associated with 
it, were originally in the form of marl or tufa intermixed with the oxide, from which the latter 
separated by crystallization ; and 2d, to the opinion that they were deposited upon the primary 
platform, since the elevation of the primary system. 
As it regards the first, I have said that the opinion is gratuitous; and I now say, that ad¬ 
mitting the theory, we may just as well admit that all the beds of primary limestone, and veins 
also, were deposits in the form of marl or tufa; for they are all alike. There is no essential 
difference in the limestone of the ore beds, and others not connected with them ; and no fact 
can be better established, than that they all have one origin, and belong to one class of rocks. 
As to the second opinion, or hypothesis, I have shown that the rocks, wherever these masses 
of ore exist, are in and connected with disrupted primary rocks ; and though the ore may 
appear to be spread over the primary platform for a little space, yet they invariably go down 
into it; or, in other words, the masses come up from beneath, instead of having been deposited 
above. 
I do not, however, in this place, propose to discuss the question of the formation of mineral 
veins; whether they are injected moulten masses, or have been separated from the adjacent 
rocks by an electro-magnetic agency. The only question I propose to raise is, whether the 
masses of specular iron and limestone were really mechanical deposits upon the primary, sub¬ 
sequent to its elevation; and this part of the hypothesis once admitted, I see no objection at 
all to the remaining part of the same, that the iron subsequently separated from the calcareous 
matter by crystallization. Such a result is not uncommon: it occurs not only among the 
