CORUNDUM IN UNITED STATES. 
135 
Continuing nearly half a mile to the north on the vein and near 
•he top of the mountain is the Melvin mine. There is a shaft here 
10 feet deep, from which drifts are run. This shaft is but 1,250 
feet from the head of the upper tunnel of the Old mine, the next one 
lo the north. It is in this Old mine that the most extensive work has 
ix'en done. Fig. 23 is a cross section of its underground workings 
ill 1899. The mouth of the lowest tunnel is but 8 feet above Walker 
lii'ook and 75 feet to the south of it. As is seen from the diagram, 
the emery does not occur continuously throughout the vein, but in 
pockets or chimneys wdiich dip into the vein about 30° N. From 
the work already done these seem to hold tliis direction rather con- 
stantly, so that the pockets 
can be approximately lo- 
cated at a given depth. 
It was in the first chimney 
of emery (see map, fig. 22) 
that the beautiful speci- 
mens of dia spore for which 
this mine is noted were 
found. 
North of Walker Brook 
and about 500 feet from 
the Old mine is the Macia 
mine, where a small amount 
of surface work has been 
done. Near the head of a 
small ravine a tunnel was 
started on the west of the 
vein to intercept it, but 
w^ork was discontinued be- 
fore the vein was reached. 
The next opening is 
near the highest point of 
the vein on the eastern 
slope of Gobble (North) Mountain, about three-fourths of a mile 
north of the Macia mine, and is known as the Sackett mine. At 
this part of the vein there was a considerable quantity of magnetite 
that was practically free from corundum and was mined as an iron 
ore. This mine was worked very extensively between twenty and 
thirty years ago, but had been abandoned until 1899, when it Avas 
reopened. The old works were near the highest point of the vein, on 
the slope of the mountain, and were worked for about 30 feet. The 
new work was started 117 feet below the mine, and a tunnel from the 
Fk 
22. — Map showing the location of the emery 
deposit at Chester, Mass. 
