a 
FOREST CITY AND VICINITY. 45 
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bed-rock, that it seems clear there must be some foundation for the opinion in fact, though I con- 
fess I am at a loss for any rational explanation of the phenomenon. The lava mud-flow which 
ents out the gravel for a distance of 225 feet is evidently of more recent origin than the gravel is. 
When the lava was struck, a prospect tunnel was run to the east, and drifts were carried to the 
west, until bed-rock was reached rising very rapidly. Upon this bed-rock there was pipe-clay, 
and above the pipe-clay lava. The main tunnel was finally carried across the lava with the same 
grade that it had been having below, and the gravel was found on the opposite side in just the 
position, with respect to grade, that the continuation of the lower gravel ought to have. Upon 
both sides the gravel dipped underneath the lava. 
The gold found in the Bald Mountain gravel is very coarse. The same is true of the gold of 
the lower stratum at Chips’s Flat, while that in the top gravel is fine. The secretary of the Bald 
Mountain Company allowed me to select a few specimens, which show well the general character 
of the gold. They were examined by Mr. Wadsworth, who says of them: ‘ These grains are of 
very unequal sizes. One contains portions of the quartz vein-stone and has its edges rubbed down. 
Another is thick and well rounded. One is flat, and either composed of two pieces welded to- 
gether, or else of one part bent over and upon a portion of the remainder. Whatever may have 
been the original form, if the gold was thin, it seems that it would easily be beaten into flat pieces 
with rounded edges. One queer form resembles a dress-hook. It is composed of quite a long, 
narrow strip of gold, that is bent partly upon itself twice. It has welded to it another smaller 
piece of gold, and it is easy to see how under the grinding, pounding action of pebbles it would 
form a rounded, thin gold grain.” The fineness of this gold averages from .926 to .936. From 
the books of the company I obtained a few statistics in regard to the yield of the gravel between 
April, 1872, and July, 1879. The area worked amounts to about 1,500,000 square feet, and the 
total yield of gold is a little over $1,500,000, of which $664,000 have been distributed as divi- 
dends. The average yield per square foot has been $1.014. The averages per square foot in the 
several years were as follows, $1.09, $1.01, $1.01, $0.95}, $0.993, and $1.00. A yield of 
$1.014 per square foot, with drifts three and a half feet high, corresponds to $7.83 per cubic 
yard. But according to the company’s books the average yield per car-load has been $2.92. 
Fach car is estimated to hold about one cubie yard of loosened gravel and rock, or one-half a cubic 
yard of rock in place. This corresponds, therefore, to a yield of $5.84 per cubic yard. These 
two results do not agree as closely as could be wished, but they are sufficient to confirm the state- 
ment that the bottom gravel is very rich. Probably the cars do not contain quite a cubic yard 
of loose rock ; their dimensions are given in Raymond’s Report for the year 1874, p. 155, as 
“41 feet long, 2 feet wide, and 24 feet high.” Assuming these to be the true dimensions, a yield 
of $2 2.92 per car-load corresponds to a yield of $7.01 per cubic yard. 
The hauling of the gravel in the Bald Mountain tunnel is done by means an a locomotive 
similar to those in use in the coal-mines of Pennsylvania. The anthracite coal used costs, delivered 
at the mine, about $42 per ton. 
The grade of the Bald Mountain channel is so much higher than is usual in the old gravel 
streams, that many persons have believed it to belong to some tributary, rather than to the main 
channel or blue lead, and that its continuation is to be looked for, not in the direction of Rock 
Creek and City of Six, but under the lava ridge to the’ east and northeast. In this belief mining 
claims have been laid out and explorations have been undertaken at several points higher up on 
the ridge, and also, in the hope of striking the main channel, at points to the west of the Bald 
Mountain mine. 
In the latter direction the most important and extensive explorations have been conducted 
by the North Fork Company. A tunnel, of which the mouth is near that of the Bald Moun- 
tain tunnel, but on the opposite side of the north fork of Oregon Creek, has been driven in 
a general northwesterly direction for nearly a mile. A branch from the tunnel has at first a 
more northerly course, and then bears around to the west, in which direction it has been con- 
tinued to and beyond the line of the first tunnel, and at a different level. There has been but 
