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mine, about three miles north of the Temescal ranch-house. Here a shaft had been sunk, in the winter of 1860–’61, to the depth of thirty-six feet; but it was partly filled with water and inaccessible at the time of our visit. A great number of the claims taken up in this vicinity were visited. They seemed nearly all to be located on seams or streaks of dark hornblende running irregularly through the granitic and highly metamorphic rocks. Although there was no appearance of tin about any of these, or any signs of regularity in the “leads,” a great many specimens were collected and carefully assayed for tin, without there being a trace of that metal found in any one of them. The excitement has undoubtedly long since died away, and it is not probable that the mass of the ore in the Čajalco mine was very extensive, or more would have been heard of it before this time.* At all events, it is a singular and interesting occurrence of this metal, and we know of no other locality on the Pacific coast north of Mexico where tin ore has been found in place. A single fragment of this substance was given us, apparently under circumstances justifying credence in the discovery, as having been found loose in the soil in the northern part of the State, near Weaversville; but the vein from which it was derived has probably never been discovered, as such a fact could have hardly failed to become widely kuown.
A belt of limestone crosses through Temescal valley, as was recognized from the occurrence of numerous fragments of this rock on the surface. The bed itself we were unable to discover. It is of a light brown color, semi-crystalline in texture, and contains minute organic bodies, of which the exact nature could not be made out.
SIR: In accordance with your request, I herewith submit a report on the coal mines of the west coast of North America, the character of the coal, the present condition of the mining interests, and a table of statistics of the amount consumed in San Francisco during the last six years. The latter item is practically a statement of the actual yield of our domestic mines, inasmuch as San Francisco is almost the only market, the outside consumption barely amounting to ten per cent. of the amount used in this city. I remain, very respectfully, your obedient servant,
W. M. GABB. J. Ross BROWNE, Esq.
Mr. Gabb's Report.
The great coal-bearing formations of the world, those from which the coals of Pennsylvania and the Mississippi valley are obtained, are not represented on the Pacific slope of the North American continent. It is not to be understood, however, that the carboniferous formation is the only one in which valuable deposits of coal have been found. Every one of the great groups of rocks has been found to yield coal in workable quantities in some part of the world. The brown coal of Germany, of nearly the same geological age as that of the Oregon mines, has been worked for many years with profit. So also the cretaceous coal of California has its analogue in New Zealand. In the older formations, the jurassic, triassic, and permian rocks, intermediate in age between the coals of California and those of the great coal-fields of the Atlantic slope, all yield their stores of carbonized plants to the miner, whether under the name of coal or lignite.
The coal deposits of the Pacific may be divided into two distinct groups, geologically. The older, including all of the workable coals of California, as well as that of Washington Territory and Vancouver island, belongs to the cretaceous formation, the analogue of the white chalk of England. This formation consists here of two members, the older of which contains the northern coal deposits; and, although it exists in California, making a large portion of the coast range, it is, so far as known, in this State entirely barren of coal. The
* The cause of the suspension of operations on these mines, as alleged by persons living in Los Angeles county and familiar with the circumstances attending the discovery, is that the claims are in litigation.
J. R. B.
upper group, on the other hand, is not found outside of the limits of California, is confined almost exclusively to the coast range, and is the coal-bearing formation of this State. The other group is the miocene or middle tertiary formation. This group
of rocks is one of the most widely spread on this side of the continent, and is known, so far, to exist from the Russian possessions on the north to Cape San Lucas on the south. In a thousand places along this vast extent it contains small seams of coal, well marked enough to deceive the ignorant prospector, but never of sufficient extent to be practically valuable, except in a single locality in the State of Oregon.
Before proceeding further, it would, perhaps, be well to glance in detail at the several localities on this coast that have yielded coal in profitable quantities. The number of these localities is small, though, doubtless, an increased demand, combined with a diminished cost of labor, will increase their number.
Bellingham bay, in almost the extremne northwestern corner of Washington Territory, is the site of one of the largest and best mines on this side of the continent. The deposit consists of about fourteen feet in thickness of coal and slate, of which I was informed that about nine feet were available for mining. The coal itself, as compared with other coals of the coast, is of fair quality, the greatest drawback being the occasional presence of sulphur, rendering it unpleasant for domestic purposes. The position of the mine, with reference to the
The mouth of the mine is barely over a fourth of a mile from the vessels in the harbor in which the coal is shipped.
shipped. The coal is, therefore, only handled in the mine and while being picked in the coal-house, thereby avoiding much of the breakage to which soft coals are subjected by repeated handlings. The vein dips at a high angle, and all of the coals and the water have to be extracted by expensive machinery.
At Nanaimo, on Vancouver island, about seventy miles above Victoria, there is a deposit of the same geological age as that at Bellingham bay, and which has been worked extensively. This mine was originally owned and worked by the Hudson Bay Company. About 1863 it was sold to a company called the Vancouver Island Coal Company. The appliances about the mine are of the most substantial and convenient kind, and the working of the mine was, at the time of my visit, a model of good engineering. The coal is claimed to be superior to any other produced on the coast, and commands a higher price in the San Francisco market than any other west coast coal.
Many other deposits of coal exist along the shores of the Straits of Fuca and Puget sound. Most of these are, however, either so inaccessible or so small that, with the present costs of labor and transportation, they can hardly prove profitable. An exception to this remark may exist in the Straits of Fuca mine, near Clallam bay, Washington Territory, opened within the last year or two. It is claimed that this is a really good mine. It will certainly need to have an extensive deposit of good coal to be of the slightest value on that inhospitable
Coming southward, the next region of any importance is Coos bay. As stated above, the coal of this locality is of tertiary age. The deposit does not seem to be very extensive, and it is so located that but a small portion of it can be worked. Most of the coal lies under heavy rolling hills at a great depth from the surface. One mine—thie Newport or Flanagan mine-has been worked in a small way for eight or nine years with very satisfactory results. Upwards of thirty thousand tons of coal have been shipped to San Francisco, and sold there at a price above the current average price of west coast coals. The deposit consists of three veins, separated by only a few inches of soft claystone, and making an aggregate thickness of eight to nine feet of good compact coal, with almost no slate or bone coal.
The deposit is nearly horizontal, dipping towards the mouth of the mine with only sufficient angle to permit unassisted drainage, and the running out of the cars by gravity. No hoisting or pumping gear has ever been or ever will be used in this mine. The coal is carried seven-eighths of a mile in cars to a wharf, where it is shot into lighters and carried a mile thence to the vessel in which it is shipped to San Francisco. Were the railroad extended so as to avoid lighterage, and the expense and loss consequent on the repeated handlings of the coal, and were the coal shipped in steam vessels devoted exclusively to this trade, instead of being carried by the one or two hundred tons at a time in lumber vessels, this mine might be made the most profitable, as well as the most popular, on the coast.
Many localities of coal are known in interior Oregon-as, for instance, on the McKenzie fork of the Willamette river; the vicinity of Eugene City; several places in the valley of the main Columbia, &c., &c.; but interior coal mines can never be of practical value in California or Oregon at a distance from railroads and navigation, unless for local manufacturing purposes, especially in the vicinity of the heavy forests which clothe so much of the surface of Oregon.
In California the coal formation is found over a large area. I have identified it in the coast ranges from the vicinity of Round valley, Mendocino county, to New Idria, Monterey county. In the former locality the coal forms a bed about ten feet thick, very impure, but with one or two seams, of about a foot thick, of excellent quality. The locality is so inaccessible, however, that it can never be of any value. At New Idria, about four miles from the Idria mine, the same beds occur again, and have been “prospected” to some extent for coal. Here they exist as beds of clay slates, barely impregnated with a little carbonaceous matter. Impure as these strata are, they are nevertheless, without doubt, the exact equivalent of the coal beds of Monte Diablo.
The Monte Diablo mines are located in a range of hills lying north and northeast of the mountain, along a nearly east and west outcrop. The coal has been found for five or six miles in a nearly continuous line, although not more than three miles of this extent has as yet proved of sufficient value to render mining profitable. The veins have been somewhat disturbed by faults, and I have reason to believe, from some examinations I made in 1862, that beyond certain limits they thin out rapidly. This is markedly the case to the west of the Peacock mine.
The deposit in this region consists of two veins, the lower of four feet thick, known as the “Peacock” or “Cumberland” vein ; the other, of three feet thick, called the “ Clark” vein. These two veins, named after the first mines in which they were first well explored, are separated by about three hundred feet in thickness of sandstones.
A number of mines have been opened at various points along the outcrops of the two veins, the principal of which are the Cumberland and Black Diamond, the Clark, Cruikshanks, Adams, Independent, Manhattan, and Peacock. Ia some of these veins work has been suspended, as, for instance, in the Peacock mine, where the vein was found so much disturbed as to be of little value. In others, work has been prosecuted with considerable vigor, and, as the shipments to San Francisco show, with some success. The greatest drawback to the profitable working of these mines has been the cost of land carriage from the mines to a shipping point on the San Joachim river. Formerly the coal was hauled from the mines to a shipping point on the river, a distance varying from six to nine miles. Recently, however, two railroads have been completed, one terminating at New York, the other near Antioch, thereby very materially diminishing the most important expenses to which the proprietors of the mines were subjected.
High hopes were at one time built on the coal discoveries in Corral Hollow, some thirty miles south of Monte Diablo, on the east face of the Coast range. Several mines were opened and much money expended. In fact a small quantity of coal was carried thence to San Francisco, but inasmuch as it has been ascertained by careful and reliable estimates that every ton of coal thus delivered in San Francisco had cost the proprietors of the mines' over one hundred dollars, ($100,) the presumption is that the mines are of but little commercial value. There is here at least one bed of coal of considerable size, but of very poor quality and variable thickness. Furthermore, it is so broken and twisted by the disturbing forces to which the rocks of the vicinity have been subjected that, even were the coal good in quality, the vein could not be relied on.
On the southern slope of the San Gabriel mountains, about thirty-five miles northeast of Los Angeles, is a locality from which some coal has been obtained. I saw a ton or more in a blacksmith shop in that city a year ago. It is apparently a little below the average of west-coast coals in quality, is soft, and somewhat impure. So far as I am aware the locality has never been visited by a geologist, and we have no definite information about it, though the general features of the region appear to point to the same geological age for this as for the Monte Diablo beds.
The distance of this mine from water transportation must render it valueless at least to the present generation.
About seven miles northeast from Oroville is a small bed of very impure coal. The material contains so much earthy matter. that it is almost a question of doubt whether it would not be more proper to describe it as carbonaceous shale rather than as coal. Of course it is valueless for fuel, though I was informed in 1864 that it was used successfully in the Oroville gas-works for the manufacture of illuminating gas.
On Eel river, about three or four miles southwest of Round valley, Mendocino county, is a bed of coal about ten feet thick, striking directly across the bed of the river and forming a little cascade. The deposit is of the same geological age as that of Monte Diablo, and although most of it is very impure, it contains one or two seams, of about a foot thick each, of excellent quality.
It is, however, so far inland and so completely surrounded by high and rough mnountains that it is extremely doubtful if it will ever become practically available.
In addition to the above localities, which have already yielded or can be made to yield coal in quantity, there are hundreds of places scattered all over California, especially in the Coast range, where small quantities of coal have been found, and where, at the same time, there is no possible chance of finding it in such quantity as to be of value. The miocene rocks contain everywhere small seams of coal of an inch or more in thickness, which, like the ignis fatuus, have led on the unfortunate miner by holding constantly before his eyes the dazzling promise of a fortune as soon as the “veins come together," or when he shall have gotten" below the water line"-prospects always in the future, often implicitly believed in, and never realized. The little inch-veins, often very numerous and quite close together, never unite, but have been known to run parallel for many yards—in fact, as far as the patience and money of the “prospector" would extend.
The coals of the west coast are, like all coals of the later geological formations, soft, more or less friable, and contain considerable water. Compared with true carboniferous coal, such as Pennsylvanian or English, they give less heat, and the loss is far greater by breakage in handling.
The following table of analyses of various coals on this coast is extracted from the report of Professor Whitney, State geologist of California. The professor remarks that these analyses were made in 1861 and 1862, and are from speci. mens taken at no very great depth :
It will be observed that there is a great similarity between all of the coals produced on this coast. There is probably, however, one weak point in the table. The Nanaimo coal is here shown to have a very large quantity of ash as compared with the California and Oregon coals. It is not improbable that the analysis may have been based on a poorer specimen than the average, though Professor Whitney assures me that it looked like a fair sample,
The subjoined table exhibits the amount of coal received in San Francisco since the year 1860. It does not, however, give the full yield of all the mines, inasmuch as small quantities of our domestic coals are shipped to inland towns and used in the vicinity of the mines. It will be seen, however, that, small as the figures are, the demand is steadily increasing, and the facilities are good for supplying this demand for many years to come :
Imports of coal into San Francisco since 1860.
Grand total.. 72, 635 116, 245 120, 545 | 135, 550 | 151, 050 147, 250 93, 460 2,858 127, 679 3, 604
9.-IRON In consequence of the present high price of fuel and labor, the development of the iron resources of the Pacific coast has not received as much attention as their magnitude and importance demands. There are numberless extensive deposits of all descriptions of iron ores in all the States and Territories on the coast. Thus far there has been but one furnace erected for the reduction of