8 
CO 
TRANSACTIONS OF THE [nov. 20, 
From all this it appears that igneous intrusions of acidic rocks 
are abundant along the contact with the gneiss, and indeed by 
the early observers they were one of the first things noted and 
commented on. 
In discussing the structural relations of the ore, it will per- 
haps be clearest to again summarize the facts which have the 
strongest significance, as was done under Ogdensburgh. 
1. The ore is interbedded in the limestone. 
2. The deposit is a continuous and single bed (or vein) which 
is bent into a synclinal fold, and also on the east apparently into 
a small collapsed anticlinal. The ore fades out qu.te gradually 
into the walls. These contain much manganese and weather 
brown. 
3. The wall rock is widely impregnated at the bend with 
franklinite and other minerals, and in at least one place (the 
Trotter Mine) is pierced by intrusive granite of a basic type. 
Other granite appears between it and the gneiss. 
4. The crest of the probable eastern anticlinal in the Buck- 
wheat Mine, and presumably also the trough of the syncline 
pitch northeast at an angle of about 28°. 
The ore dips southeastward with an inclination in the 
western (or front vein) of from 60°-87°, but in the eastern 
portion it is nearly vertical. 
The first of these statements is the universal testimony of all 
who have written of the ore, but it is true here, as at Ogdens- 
burgh, that the dip and strike of these massive, crystalline 
limestones are often very obscure. Whether the apparent lami- 
nations in so disturbed and metamorphosed an area represent 
original planes of deposition is not absolurely beyond question, 
although I think in general that they do. 
The second of these statements is proved by the excavations 
at the south end. In the south end of the second level of the 
Buckwheat Mine a cross drift has been run to the front vein. 
It is very evident that along this drift the ore flattens to the 
horizontal and then rises again to an inclination beyond the 
vertical, so that a slightly collapsed fold is indicated. The 
layers or bands of ore that are next the hanging of the front 
vein are next the foot of the back. The synclinal fold is 
beyond question, but whether the back vein is a crushed anti- 
cline is less certain, although I think it is and have so drawn it. 
This anticlinal structure was suggested by Bemis and Woolson 
in the thesis cited at the outset. In favor of such interpreta- 
tion, it may be said, that 
1. The ore is of double or even greater width. 
2. After it has pitched below the surface, the roof is a marked 
