274 
[Assembly 
that the writer hazards much, and that he jeopardizes what Httle re- 
putation he may have acquired as a geologist, or by it subjecting him- 
self to the charge of misunderstanding the peculiar requisites of a ma- 
nufacturing establishment of this kind. In justification of the remark, 
I observe, that it is made after a careful examination, not only of this 
section of country, but of many others celebrated for the manufacture 
of iron ; and that I have spent a portion of three successive years in 
this work, and each examination has but confirmed opinions which were 
early expressed, and which will be found in the first annual report to 
the Legislature of New-York. The writer, therefore, has no fear that 
it will be proved hereafter that he has misunderstood his subject, and 
overrated the resources of the region under consideration ; and he has, 
moreover, no doubt but that events will prove, that he might have just- 
ly given a greater latitude to his observations, and still been found 
nearer the truth, and nearer what will be realized in the future opera- 
tions of this branch of business, as it will be conducted at the Mcln- 
tyre establishment. 
Before I proceed to a detailed account of the veins of ore at New- 
comb, (or as it is now more generally called, the village of Mclntyre,) 
I shall present some general considerations in relation to the species 
and varieties of ore, and its mode of occurrence. 
SECTION I. 
The Species of Ore, and the varieties into which it is divided by mi- 
ners. 
Mineralogically considered, the ore which is the subject of this re- 
port is the octahedral iron ore of Prof. Jamison. It is sometimes de- 
nominated the oxidulated iron ore, but more commonly the magnetic 
oxide, in consequence of its obedience to the magnet. Colour, usual- 
ly iron black ; lustre, more or less metallic ; streak, black ; opaque ; 
brittle; hardnesses . 5 to 6 . 5 ; specific gravity— 5 . 09 ; cleavage, parallel 
to the planes of a regular octahedron. Structure usually crystalline, 
but its occurrence under a regular form is quite rare in any of the veins 
in the northern counties of New-York. In fact, in an examination of 
more than twenty veins, but one crystal has fallen under my notice. 
There are a few instances, in which the coarse crystalline varieties ad- 
mit of cleavage parallel to the planes of the primary form. Its occur- 
rence there is in a granular form, varying from fine to coarse, or ra- 
