terfered with by judicial proceedings. The waters of these rivers find their way to the ocean through deep, narrow cañons, along which there are no farming lands of any extent, none whatever so situated that they can receive any damage from the hydraulic slums. As these streams are not navigable, and the Klamath, which receives the waters of the other two, debouches directly into the ocean, there being no bay or harbor at its mouth, no injurious filling up or shoaling can there result from these slums, however great the quantity discharged from the hydraulic mines. The auriferous gravel banks along the Klamath, are said to be very extensive, occurring in bars and bunches for many miles on either side of that stream. These gravel deposits are rich in gold, and enjoy entire freedom from the volcanic ash and lava flows that so encumber many of this class of deposits further south, rendering the working of them by the hydraulic process difficult and expensive or preventing it altogether. Water in great abundance can be introduced upon these Klamath mines at little cost. They can also be outfitted at small expense, lumber in that country, which is everywhere well timbered, being extremely cheap. The winters are mild, it being possible, so far as climate is concerned, to continue gravel washing the year round, as has been done in the past. A good deal of attention is now being turned to this section of the State where a number of important hydraulic enterprises are contemplated in the near future.

GOLD BLUFFS AND BEACHES.

There exists on the shores of the Pacific Ocean near the mouth of the Klamath River, in Humboldt County, a large area of beach containing more or less gold in the beach sands. The auriferous character of these sands has been known since an early period in the history of mining in this State. They have been worked in a desultory manner by crude process for many years without any remarkable success. During the last two years, however, more systematic working has been inaugurated, and the industry promises to become an important one. This gold region has lately been visited by Mr. H. W. Chase, of the United States Coast Survey, and also by Dr. John W. Hood, of San Francisco, and James H. Crossman, M. E. The detailed description of the observations and experiments of these gentlemen throw much light on the character of this gold field, its formation, and the method of working pursued for saving the gold.

Mr. Chase describes the coast line coming from the north after leaving the Klamath River as being extremely broken and rocky; at a point about 4 miles south of the river banks deposits of sand appear, although the commencement of the bluffs proper is at the mouth of the Ossigan Creek, and 7 miles from Klamath River, for 8 or 10 miles there is an almost unbroken line of gravel cliffs varying from 100 to 500 feet in height; many of the bluffs are absolutely vertical and in some instances overhanging. The mountains back of this sea escapement are all one immense mass of gravel of varying size, and distinctly marked in layers or stratifications. This gravel can be traced across the country, northeastwardly, to a point on the Klamath River about 30 miles distant.

The average height of this cliff above low water-mark is about 200 feet, composed of auriferous loam, clay, gravel, sandstone, cement, &c. The cliff described is at the lower end of the bluffs and near the mining works. The sand is placed in an inclosure called the sand corral. A large lagoon near by furnishes the water for separation, supplied by a

stationary engine and force-pump. The washing is done in long toms with silver coated plates on which quicksilver is applied. During the week of his stay in a seven days' run they cleaned up and retorted from the two machines in use $1,000.

The experience of the successive proprietors of this extraordinary gold deposit proves that immediately after a heavy cave or slide of the bluff the beaches are richer and its gold coarser, and it is strange that up to the present time no artificial means have been resorted to in the way of blasting down the cliffs or undermining them by hydraulic process to enrich the sands of the beach. The sea working ceaselessly night and day is the great natural disintegrator, pulverizer, and crusher, as well as the concentrator of the precious metals from the immense deposits contained in the bluffs, and man has but to gather the results of nature's unceasing and tireless work. Many ideas have been advanced as to the possibility of gold in quantities and coarser in character being found be yond the surf line, predicated on the fact that in conjunction with black sand gold has been repeatedly brought up from the bottom of the sea by the sounding leads of sailing vessels.

Dr. Hood is of the opinion that the bluffs have been the outlet of some ancient river, probably those now known as the Klamath and Trinity Rivers, which take their rise above the great auriferous belts of California and Oregon, carrying in suspension immense quantities of auriferous gravel, depositing it along its course, eventually filling up the different estuaries or deltas which, owing to some great volcanic disturbance, became what is known as "The Gold Bluffs."

That this theory is correct is proved by the fact that the timber on the bluffs and along the course of the gravel of the old river bed is of more recent growth than that of the outside belt, and in the face of the bluffs in many places are found trunks and stumps of the California fir in a partially fossilized or carbonized condition. None of these trees are found growing within 50 miles of the bluffs.

The method of working the beach sands and bluffs is similar in all the claims, and is described by Mr. J. H. Crossman; the system of working adopted is as follows:

When rich deposits or concentrations are seen on the beach by men in the company's employ notice is sent to their station, and men and mules with sacks (alforjes) are dispatched to gather them, but, owing to a want of system or tardiness in arriving, frequently large portions are temporarily lost from the effects of the incoming tide and surf, which bring fresh accumulations of auriferous material, covering the concentrations, or the strong undertow may take them seaward and break up the deposit. It is not an uncommon thing to gather 100 tons of these sands in a day, providing everything is favorable. The average, how ever, is 10 tons, with an average value of $5 per ton, though the aver age assay value is much higher.

The company employ from 5 to 10 men as they are required, paying them $40 per month and board. When short of men they employ Indians; their pay when working is $1 per day. When the men are not employed in working the sands at the canal they examine the beach for fresh deposits.

The Union Gold Bluff Placer Company use water pumped from the ocean in their machines. Fresh water would be better, as salt water is objectionable on account of its specific gravity being greater than that of fresh and more readily carry ing away the light, scaly particles of gold in suspension. The amalgamation at Gold Bluff is imperfect, and the loss of gold must be great. The machine in use is the ordinary long tom,

12 feet in length, with hopper of sheet-iron, coarse holes. The sand is shoveled into the hopper, 15 miner's inches are turned on; from the hopper to the copper plate is a drop of 5 inches. The plate is 4 feet long, which is charged with quicksilver from a bottle as often as required. From the bottom of the tom the pulp passes off, is forced through a reservoir of quicksilver, thence to the dump. The proportion lost is probably greater than the amount saved.

The gross proceeds of the Union Gold Bluff mines from January 1, 1875, to January 1, 1883, were $147,733.16, and the expenses for the nine years averaged $6,000 per year, or $54,000, leaving the company a net profit of $93,333.16. Dr. Hood has specially examined the Pioneer ground, which is of the same character as the Union. From his report the following extract is presented:

"The property has not been worked as an hydraulic mine, but for the past twenty-five years has been successfully operated as a beach mine; that is, gathering the auriferous sand found at the base of the bluffs after stormy weather has broken them down, and saving by amalgamation the gold therein.

"It is estimated that but a small percentage of the gold which was washed out of the bluffs has been collected, as the main portion is washed away to sea, where, by action of the currents, it is distributed along the coast for hundreds of miles. Notwithstanding this rude method of collection, over $1,500,000 have been collected on the beach from both bluffs, more than half of which came from the upper or Pioneer Bluffs.

"The gravel has an average depth of 200 feet, at least, from surface to bed-rock, all being auriferous, and yielding on the average 20 cents' worth of gold to the cubic yard. Some streaks are very rich, giving $135 per ton by actual working. There is no top soil to speak of-gold from the grass down-no large bowlders; very little cement or clay. The gold is fine, but easily saved in the sluices, and averages .957 fine."

This form of deposit and class of mining is not wholly confined to the beaches of Oregon and California, but is carried on extensively in New Zealand, and is described in an English work entitled "Gold; its occurrence and extraction," written by Alfred G. Lock, F. R. G. S., and published in London, 1882 (p. 526).

RETROSPECTIVE REVIEW.

The condition of mining, with the sole exception of the uncertain status of hydraulic mining, may be summed up as one of unusual prosperity and great promise for the future. The drift mines of Sierra, Plumas, and Placer Counties have more than maintained their annual production, as will appear by reference to the details under the general title of "California," and many miles of new territory are being opened by long tunnels. The output of the silver mines of San Bernardino County has been a matter of surprise to the most sanguine owners, and yet promises to be rivaled by new discoveries in Shasta County. The business of the foundrymen in the construction of mining machinery for use in this State has been unprecedented. Most of the large orders emanate from the owners of so-called low-grade quartz mines, which have heretofore been worked only for pockets by tracing small veins. Under the present system the whole mass, sometimes to a width of 100 feet, is milled, and if the ore yields $3 per ton the owners realize a fair profit with a large mill. The leading operators of California have abandoned distant fields and are now seeking to develop the resources of their own State.

PRACTICAL HYDRAULICS AS APPLIED TO THE MEASUREMENT OF WATER IN MOTION, TO MINING AND OTHER INDUSTRIES.

BY P. M. RANDALL, C. E., San Francisco.

The commercial value, as well as the physical properties of water, renders a knowledge of the manner and means of measuring its flow correctly, under different conditions, highly important to all concerned in its industrial uses.

The miner asks how many cubic yards of earth, gravel, or tailings a given quantity of water employed under certain conditions will break down, wash out, or remove; the farmer inquires how much land can be properly irrigated with the same or certain other quantity of water; while the manufacturer and millman seek to know what quantity of water falling vertically by the force of gravity through a given distance will develop a definite amount of mechanical power.

The determination of the quantity of flowing water is common to the various industries, but independent of the uses to which the water shall be put.

The present article has been prepared with the view of answering in the most simple and efficient manner, these questions with respect to the measurement of water in motion; as through vertical openings, over veins, in pipes, in canal, or ditches, in natural streams and through nozzles; with respect to the quantity of water required for various mining purposes, and for the purposes of irrigation; and with respect to the power of water as a motor.

In mining operations, the measure of the flow of water is usually expressed either in cubic feet or in miner's inches. In computing the accompanying tables, the unit of measure adopted is one cubie foot flow in a second of time.

MEASURING DEVICE.

The device for the measurement of the flow of water, mostly employed in the mining regions of California consists of a large wooden box a foot or more in depth, according to the requirements, in one end of which is a rectangular discharge opening whose width should not exceed one-half the depth of water below it. Above this opening is a head-board, adjustable like a vertical gate, by means of which the size of the opening can be increased or diminished.

Head. The sum of the vertical width of the head-board and half the vertical width of the discharge opening is equal to the head or pressure under which the water is measured.

The thickness of the sides of the opening, varies in different measuring devices, from 1 to 3 inches. The surface of the water, in its passage through the box, is kept at the level of the top of the headboard. Care should be taken that the discharge velocity shall not be affected by the velocity of the approaching stream.

APPLICATION OF THE VERTICAL MEASURING DEVICE."

(1) Assume the discharge opening 50 inches long, 2 inches wide, and the width of the head-board 3 inches; then will the area of the discharge opening be 50 x 2 = 100 square inches.