IMPROVEMENTS IN MINING APPLIANCES.

Grey River Argus, Volume X, Issue 840, 6 April 1871, Page 2

IMPROVEMENTS IN MINING APPLIANCES.

[weekly bulletin.]

The report upon our- placer mines just made by Mr W. A. Skidmore to the U.S. Mining Commissioner, shows a most encouraging condition. The last year has been signalised by the introduction into California mining of improvements which must give new life to the business, and add millions to our annual yield of gold. Chief among these are the hydraulic nozzles, which, while reducing the expenses, more than double the working power of the hydraulic claims. Of these there are three now in Use -r- Craig's " Monitor," Fisher's " Knuckle Joint," and Haskin's "Improved Nozzle," all three, though by different devices, accomplishing the same end— that of dispensing entirely with the use of hose, by the attachment of a move'able and easily managed nozzle directly, to the iron water pipe, thus making it possible to direot against a bank a stream of as great volume and pressure as iron pipescan be made to carry without bursting. It may not be amiss to some of our readers to explain that hydraulic washing— nq\y the most extensive branch of gold mining in California— is conducted by directing against a hn-sjde powerful streams of water, which cut into an. ; undermine the bank, the water as it runs oft carrying with it the disengaged dirt and gravel through long! flumes (sometimes over a mile in length), where riflles charged with quicksilver arrest the gold as it is separated. When hydraulic mining first commenced, canvas hose was used to convey the water from the ditches into the claims and to the points where it was to be hurled by the foroe of the

fall against the banks. Though made in the most careful manner and of the strongest sail cloth, such hose could not > bear the pressure of a fall or head -©£ more than -eighty or one hundred feet, and moreover rotted rapidly, and wan constantly giving way. The rapid wearing. x>t the canvas hose, as well as the necessity of using larger streams and greater force to move the firmly compacted dirt and gravel, finally led, in all large claims, to the substitution of sheet* iron pipej to bring the water from the supply ditches into the /claims. Thus a great increase of the volume and force of the water was. made j»ssible ; bnt the increase in the power and volume of the streams used was still limited by the ability to direct them by hand, and the necessity of having a flexible discharge-piece,; connecting the pipe with the nozzle, and permitting the latter to be moved as occasion required. However, by making the ' discharge .piece of stout canvas covered'with a network of matting ' of strong . rope, the : : size and power of the streams used* and consequently their efficiency, was largely increased. But still the desideratum of an easily managed stream as powerful as iron pipes could carry was not secured until the study of the problem by bur miners gave birth to the inventions we have alluded to, and which are already almost in general use. • These new hydraulic nozzles are attached directly to the iron pipe, and by a simple but ingenious contrivance (which differs somewhat in each invention) are given both a lateral and a perpendicular motion, which can easily be directed by one man. Instead of two 1 hundred and fifty inches of water with a head of from one hundred and fifty feel, twelve hundred inches of . water, with^ a head of three hundred feet can now be driven against a bank in a single stream. The saving thus effected is enormous. It - ia not only that the water formerly sent through seven or eight ordinary hose pipes, each requiring from one tcx rthree men, can now ; be . managed by a sißgle hand; bub its 'efficiency is greatly s'increased. The disintegrating power of water forced upon a bank in one stream if at least double that of the -same amount thrown in two separate streams. Closely compacted gravel and hard cement, which water, as formerly . used, could not ,, move, and which required the pick or the blast, are easily disintegrated and washed away by the tremendous force of the gigantic streams now used. These inventions,. too, • save human life as well as human labor. Formerly, the pipe-holders had to stand so close to the banks that they were frequently crushed by! the toppling over or caving of immense masses, of earth., y-Biit with the powerful streams now,, coning into use they can remain at a safe i distance and yet do more execution than b'efdre.

These inventions must largely increase the area of hydraulic mining, and the yield of ;our : ancient placers. Claims in which the working expenses formerly took ninety per cent of the yield, can now be worked so as to leave fifty or sixty^ per cent as profit,and hydraulic ground formerly worthless has become valuable. In many places too, as between Greenhorn creek and Bear river, where the ancient" channels have . been worked through shafts And tunnels, the owners 'ofithe claims are now fitting up, , or contemplating fitting up hydraulic apparatus, and wUI sluice off the'top dirt. Withthe improved machinery this operation inll pjiywell, while, in wcwking the bed-rock^ all the expense : of timbering, and the dead work .that . must. . be, done ,in^pjpjpe.cj|ng underground . will be while the ancient channels thtfs ejxposed to the open air can be easily followed. , Inthe milling of cement, too, an important discbyj^ty has recently been made. By the substitution of quarter-inch acreens for the oneeighth inch screens formerly nßed/itis found that the capacity of the mills is in, creased twenty-five per cent withoutre * duction in the yield of the cement. In the best managed hydraulic claims,' the bed-rock, after being 'washed/ is picked for the harder portions of the cement-re-maining, and carefully swept with .4sajne brooms by -Chinamen, This matter is passed through milk, run cheaply by water ) power, ;and yields largely; l Near Timbuctoo, the bottoms of abandoned claims are being re-worked in this manner with profitable results, and it is probable that many old claims ' will now be reworked for. the hard; but,, rich cement which could not be moved by thesniali streams formerly used, but which; &ra now by the aid of, the improved nozzles be easily washed away. Great improvements have likewise been made in the means of cutting through .rock, as. important in hydraulic a^Jn quartz mining,. for in nearly all the Hydraulic claims long tunnels have-to be cut to. furnish outlets. The introduction," of giant powder, /against which the Valley miners so foolishly and so vainly struck, by reducing the amount of drilling required, and permitting, the substitution of single handed . for two-handed drills, reduced the expenses of tunneling from twenty to thirty-three per cent; And now cornea an invention which will make a further enormous saving' boWluf expense and in time. This is the diamondpointed power drill, which bores through rock almost as -quickly as a carpenter with brace and bit bores through a plank. At Telegraph Hill, it bored twenty feet holes in three hoars, whioh drilled hand .required the. labor of six men for from twenty to twsnty-five days, and 'haa been tried in various parts of the.«ijate with like results, showing itself capable of going through even the white' crystal quartz, the hardest rock in California, at the rate of three feet per hour. In the long ?270 feet tunnel of the Blue Point Hydraulic Company now being cut at Smartsville, where the rock is so hard that a gang of six men have worked for a month without making ten feet? the diamond drill has shown itself capable of boring at the rate of an inch a minute. One of these machines is now being made at the Fulton Foundry for use in thin tunnel. It will be run? by oompr-essed air, it being impossible to use steam in long tunnels on account of the heat, ' Hie escaping air performing also the task -of ventilation. In this machine, the" drills will be carried on a truck^ which, one man, can run up to the foc^ qf the tunn.e.l op back again in a moment, and will be bo arranged that the holes can be bored in. any place or at any angle required. The cost of the entire machine, will be 10,000dol. a sum which is insignificant compared with -the cost of trotting these long tunnels by hand, . Besides its use fo* blasting purposes, the diamond drill nrast as it can be driven in for six or sewn hundred feet, taking out a core of the rook as it goes along, thus, in many «a»e». aytag expenttfa shafts and drift*. ri .