No. 50.] 
283 
which are at present hypothetical. The surfaces of rocks when recent- 
ly uncovered, present the usual water-worn appearances, as grooves 
and scratches. Having given a general account of the nriagnetic oxide, 
as it occurs in the northern section of the State, and also a brief outline 
of the geology of the county of Essex, we are prepared to furnish a de- 
tailed description of the ores of Mclntyre. 
SECTION X. 
Sandford Ore. 
This mine is situated upon a hill which rises 600 or 700 feet above 
Lake Sandford. It rises so gradually Irom the eastern border of the 
lake, that loaded teams may be driven to or from the mine, with ease. 
The greatest angular slope, is occupied by the ore, but does not proba- 
bly exceed 25°. The portion below the mine towards the lake has a 
slope not exceeding 5°. The distance of the middle portion of the vein, 
from the lake, is about 80 rods. The ore occupies the western face of 
the hill, down which the slope is so equal, that an inclined plane might 
be constructed from the mine to the lake, for the delivery of ore, into 
boats, in case this measure was deemed expedient. It is two miles 
south from the village. 
SECTION XL 
Mineralogical Character of the Sandford Ore. 
The colour of the ore is black ; it is moderately coarse grained, being 
in this respect intermediate, between the fine grained ore east of the vil- 
lage, and the coarse black ore on which the works are located. Struc- 
ture of the mass, always crystalline, but rarely if ever, compact ; lustre, 
dull ; streak, black ; sufficiently hard, to give sparks with steel ; tex- 
ture, generally rather firm, but never tough, and very frequently fria- 
ble ; constituting what miners call, shot ore. It never occurs in ciys- 
tals. The surface masses of the ore, are magnetic, but rarely possess 
polarity. In the mass, the structure is slaty, resembling in this respect, 
a regular rock formation. It is probably owing to crystallization, as it is 
very difficult to conceive this structure to have been produced by depo- 
sition. It is not, therefore, properly speaking stratification, though the 
]ines of separation are parallel, like those of veins of slate or gneiss. 
The existence of this kind of structure, favors very materially, the quar- 
rying of the ore. It is even possible to remove large masses, with the 
assistance of an iron bar. The dip of the layers, is about 75° to th^ 
east. Much of the ore after it is raised, and has been exposed for a 
