880 SUPPLEMENTARY INVESTIGATIONS IN THE GRAVEL REGION. 
known as the Enterprise, which lies at the southern base of Mooney Flat Hill; the opening of the 
Mooney Flat mines, on the northern side of the hill, near the head of Nebraska Ravine ; the con- 
solidation of many of the water and mining interests ; and, in general, the improvements which 
have been made in order to increase the production or to diminish the expenses of the mines. 
As mentioned in my previous report, the frequent consolidations of companies, or changes in 
ownership, have made it sometimes difficult to tell what piece of property was referred to by any 
given name. This difficulty is not yet entirely overcome, for many of the old names are still in 
common use, although at the present day nearly all the water and mining interests, by consolida- 
tions and sales, have come into the possession of the Excelsior Water and Mining Company, an 
organization formed, I think, in 1875. This company now holds, according to the statement of 
Mr. O’Brien, the superintendent, about seven hundred acres of gold-bearing gravel. The only 
other large owner of mining ground here, saying nothing of a few small claims, is the Nevada 
Reservoir Ditch Company, which holds the Blue Point claim, comprising about one hundred acres 
between the Blue Gravel and the Smartsville Consolidated ground. Including what is still to be 
“cleaned up” on the bed-rock, where the most of the top gravel has been removed, there must 
be nearly a thousand acres from which a greater or less yield of gold may be expected. 
The Excelsior Company owns one of the oldest and most valuable water-rights in the State. 
One of its ditches was begun as long ago as 1851. The ditches belonging to this company, taken 
together, will measure more than one hundred miles in length. The water is drawn from the 
South Yuba River and from Deer Creek, at points so low down that there is no danger of injury 
from the accumulations of snow in winter. The capacity of these ditches cannot be given in 
detail from any data at my command, but, with the aid of storage reservoirs, they can be depended 
upon for a supply of three thousand miner’s inches per day of ten hours during the dry season, 
which amount can easily be doubled in the winter. In Raymond’s report for the year 1875, 
page 96, these amounts are given as twenty-five hundred, and seven to eight thousand for summer 
and winter respectively. 
The Nevada Reservoir Ditch Company draws its water from Wolf Creek, near Grass Valley. 
The accompanying map of the Smartsville district (Plate M), which I owe to the kindness of 
the Excelsior Company, is a tracing from a photographic copy of the original manuscript map 
prepared a few years ago by Mr. Bowman. I have copied only those parts which were essential 
for the work at present in hand. A lithographie copy of the same map may be found in Ray- 
mond’s seventh annual report, for 1874, page 142. By reference to this map, where the dotted 
line represents the known outer edge of the rim-rock, or the line of junction, on the surface, of 
gravel and bed-rock, it will be seen that the gravel deposit extends, starting from a point above 
Mooney Flat near Deer Creek, for about a mile in a direction a little west of south, to a point half 
a mile above Smartsville, where it makes nearly a right angle, and continues to the westward for a 
distance of two miles farther, where it is cut off by Big Ravine. 
The width of the gravel deposit, measured from rim to rim, varies from an eighth to something 
over half amile. The thickness of the gravel has also been very variable, owing to the inequalities 
of the original surface. The highest banks at Smartsville have seldom, if ever, exceeded three 
hundred feet in height, though a bank of nearly four hundred feet may be looked for if a connec- 
tion is made through from the Enterprise mine to the mines at Mooney Flat. 
As before stated, the bed-rock in the deepest part of the channel is exposed for about a mile 
between Timbuctoo and the Blue Gravel claims. For the rest of the distance to Mooney Flat the 
position of the deep channel is not known, though inferences may be drawn from the appearance 
of the rock reached on the westerly rim at the Enterprise mine. The deepest bed-rock known is 
at a point about a quarter of a mile from the western end of the gravel. From this point the rock 
rises slowly, so far as known, in all directions, to the west as well as to the east. From observa- 
tions taken at the Babb claim, at the Blue Gravel, at one point between the two just mentioned, 
and at Mooney Flat, the average grade of the bed-rock for the three miles is not far from one 
hundred and thirteen feet to the mile. In regard to the altitude of the bed of the channel at 
