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By Washing, is meant every process which depends for its efficacy upon the superior I. gravity of the precious metal, as compared with the substances with which it is mixed, in a state of such freedom as to allow it to subside from then after being mechanically suspended in water. Of these processes, that of panning may be considered the type. The appliance used in this method is a shallow cone-shaped pan or dish, into which the auriferous sand or o is thrown, and agitated by hand with water. The gold particles subside to the deep centre of the pan, while the lighter matters pass off with the water, which is allowed to escape over its sides. It is obvious that in such a process small particles of gold —too small to be visible to the naked eye—must be lost; for, notwithstanding its weight, gold may be so minutely divided as to float upon the surface of the water, or to remainin it, and move with it, in a state of indifference. To this class of machines belong those in which the auriferous matter, suspended in water, is allowed to pass down inclined planes, meeting in its course, at the bottom of the stream, certain obstructions, which detain the gold, while they allow the lighter matters to pass on and escape. The machinery employed in the mines of the Ural, where the work is done chiefly by stamping and washing, is an illustration of this process. In another apparatus the hide of animals, with the hair on, and turned against the course of the stream, is employed to secure the fine autiferous particles as they find their way to the bottom of the stream. The hides are occasionally withdrawn, and freed from their precious loodby washing in proper vats. The cradle-rocker, or long tom, of the Californian emigrant, is anotherapplication of the same principle. The “Dolly T. may be used either as a washer or amalgamator. When used as a washer, the dasher or agitator is employed to mix thoroughly with water the auriferous sands or earth that may be thrown into the tub by violentlyo: them. It is then withdrawn, and the suspended substances subside to the lower portion of the to arranging themselves in the order of their specific gravities. The water on the top is then drawn off by means of a tap in the side of the tub, when the golden o will be found at the bottom of the remaining mass. folls an amalgamator, the agitator is employed to bring the mercury and pulverized ore in contact with each other by the rapid revolution and agitation of the whole Isláss, . The process of smelting will not be further alluded to in the present paper, inasmuch as it is evidently a pro**hot applicable to the general wants of the gold-seekers of the present day, because it requires means and apRimonot within their reach. And as has been before own, it is also a process much more ex pensive than the o now known of securing gold from its parent

Next in order is the method of amalgamation, which is the one most relied upon by practical men for securing the *ied product. The process of amalgamation involves, of * the previous reduction of the ore to a finely-divided * in which alone the mercury can seize upon the gold **ute it; and the great objecthitherto had in view has on to produce machinery capable of bringing the rock to such A state of powder as to allow the mercury to be bought into complete contact with every particle of the * metal. This has been attempted by means of "oily for crushing, stamping, and grinding.

More breaking down of the or is a com aratively, easy *., The question between the .#. hitherto otelis simply one of the quantity of work done with a given amount of ". for they all, at greater or less o, lesform the operation of crushing to a coarse powder with about o perfection. It is between this ***ision and an impalpable powder that the differthce between different machines becomes apparent.

the machinery for pulverizing used in gold-minin

*is chiefly of three kinds; šum. hers, an

Grinders. In California the principal ones in use have hitherto been the Mexican Arrastras, and the Chilian MIll. Stampers may be driven either by machinery or by hand. There is one apparatus worked by machinery. in which vertical wooden beams are so attached to large masses of cast iron, that when raised by cams, or eccentrics, placed around a moveable axle, and corresponding with tongues attached to the lifters themselves, they fall on the ore placed beneath them, and by repeated blows reduce it to a fine powder. A large wooden trough is placed below, in which are openings filled with gratings of perforated sheet-iron. A stream of water flows through this trough, and carries out with it all the particles that are sufficiently fine to pass through the perforations in the sheet-iron. The gold contained in the powder is collected and preserved by subsidence, on the principle before described. In the hand apparatus, which is worked by a winch, the stampers are lifted and dropped by means of an endless chain, which catches into tongues on the upper ends of the stampers. The links and tongues are so arranged that the stampers are lifted and let fall in succession. . An inclined table for collecting the gold by subsidence is attached to the apparatus; the arrangement for carrying off the finely-powdered ore in water being substanially, the same as in the other machine. In stamping machinery there is a great loss of power by friction, as there are necessarily numerous rubbing parts. There is also another difficulty. When reduced to the state of coarse sand, the ore begins to pack beneath the pestles, and though the first coarse division is effected with great rapidity, the subsequent part of the process is extremely slow and laborious. Simple percussion, more. over, does not seem to be sufficient to reduce such substances to the state of an impalpable powder. There is needed, in addition, a rubbing or grinding motion. Indeed the ore has to be passed from the stampers to the mill, before it is supposed to be ready for the amalganator. In a rude form of mill, known as the “Mexican Raster.” or “Arrastra,” in California, the grinding is effected by the dragging or rubbing of stone mullers over a bedstone of hard granite, enclosed by a wooden tub. This process is of course slow, and the friction is immense. The reduction to fine powder is, however, most effectually accomplished. A large rough stone is sometimes rolled over the stamped and broken ore, as a modification of the above apparatus. A crushing machine, which has attracted a good deal of public attention, and was thought at one time to promise good results, is that of Mr. Cochrane. In this machine the wheels of the Chilian Mill are replaced by balls, which are worked by the pressure of a revolving dome of iron placed above them. The idea was no doubt ingenious, {. the leading defects of the Chilian Mill are retained, in addition to which there is the friction between the balls and the dome, which, as it is the source of power, must be at least equal to the work done. The basin remains horizontal, and the ore, after being pulverized, has to be amalgamated in a separate apparatus. The wear of a machine, depending for its power upon the friction of iron surfaces, must obviously be very rapid, and the resulting powder must have a very considerable admixture of iron in a state of fine division— the result of the wearing away of the superincumbent dome. - Rollers are sometimes used for crushing and reduction to a powder. Theobjection to them is that they do not crush the ore sufficiently fine. They only act at a single line ofcontact, and as there is an ... Qr imparting elasticity to prevent accidents, which allows the rollers to recede from each other when, a lump of unusual hardness presents itself, much undivided ore must pass through along the whole line of the rollers whenever they are kept apart by such a contingency. This has to pass down the sieves and again be lifted and passed through the rollers. And it is found after all that the powder produced is comparatively coarse; too much so, indeed, to admit of perfect amalgamation. All machines which come short of producing an impalpable powder, may safely be considered as failing in the most essential pre-requisite for securing all the gold from the ore. The universal complaint among the mining people is that no machinery will grind the ore sufficiently fine to permit perfect amalgamation. The Chilian mill is undoubtedly the best of all the old contrivances for reducing gold ores. It unites several of the principles which are most essential to the perfect performance of the operation. It pulverizes, washes, and amalgamates at the same operation, and needs but a few modifications to become a neat, perfect apparatus for all those processes. In this mill large and heavy cast iron wheels move round in a trough, over the ore to be operated upon. A large quantity of quicksilver is placed in the bottom of the trough, and water is supplied at the top. The ore is ground by the double action of rolling and grinding, for the outer side of the wheels, which are attached to a centre shaft, must slip as well as roll. The action is like that of the mill used in potteries for grinding clay and broken earthenware. Amalgamation takes place simultaneously with the grinding, and the refuse is carried off in suspension in water. Having spoken in terms thus favourable of the old Chilian mill, this may, perhaps, be the proper place to enumerate the qualities which it is thought a perfect gold ore reducing apparatus should possess. First,--It should grind the ore to an impalpable powder, in order to do which it should have a combined rolling and rubbing action. Second,-It should amalgamate at the instant of crushing. Third, It should amalgamate at the point of crushing or below the surface of the mercury. In order to effect this the mercury must be kept constantly at the crushing point. F.". should heighten the affinity of the mercury for the gold by the application of heat. Fifth,--It should lose no mercury in the process. The first point—the necessity for fine division—has already been sufficiently insisted upon, and is indeed too obvious to need further remark. 2nd,—The necessity for amalgamating at the instant of crushing, will be apparent on reflecting that the particles of gold may be so small, or so flattened into flakes or leaves as to rise in the water and pass off with it and be lost. Or they may, in being mixed with the refuse mud, become so coated over with it, that the mercury will not seize upon them at all. There is no doubt that much loss has occurred in this way. 3rd, Amalgamation at the bottom of the mercury is a int which seems hitherto to have escaped the attention it deserves. The surface of mercury is covered at all times with a film of oxide which must interfere materially with the perfection and rapidity of its action in amalgamating. But in addition to this it is constantly covered in practice with the mud and refuse from the grinding operation, which much increases the difficulty of bringing . whole of the gold—in its condition of flour of gold— into perfect contact with its surface. But at the bottom of the mercury both of these difficulties are entirely avoided. In order that amalgamation should take place at the bottom of the mercury, and at the instant of crushin 3, it is necessary that the mercury should be kept constantly at the crushing point. There it seizes upon the fine particles of gold the moment they are liberated from their rocky matrix. The increase of attraction which takes place between old and mercury by heat, is a point of great importance. t may be illustrated by o experiment. Take a sovereign and dip it in a spoonful of cold mercury, and observe what proportion it will take up. Then heat the mercury by holding a spoon over the lamp, and notice the greatly increased quantity which will cling to the coin. It was this simple trial, indeed, that resulted in an

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important improvement in gold amalgamating apparatus, which will shortly be noticed. The loss of mercury has been a very serious evil in amalgamating machines. It has been broken up in the process of grinding, and passed off in a finely divided state with the refuse. If these principles thus explained are now applied to the Chilian mill, it will be found that— 1.—The grinding of the ore is performed in this mill with a good degree of persection, it having the rolling and rubbing motions combined. 2 and 3.—It does not amalgamate at the instant of crushing or at the bottom of the mercury, because, the trough being horizontal, and the action of the wheels being all in the same direction in the trough, a current is created around the trough, which carries mercury and ore around with it, and causes the mercury constantly to elude the lower part of the wheels where the crushing is going on. 4.—No heat is applied, but the mercury is cold and “stiff.” 5.—In case it is attempted to grind and amalgamate with comparatively little water, the mercury is very badly broken up by the action of the wheels, and much loss is the consequence. With a greater quantity of water the current produced operates as before described, to carry the mercury away from the crushing point, and also to wash the powdered ore away before it has been sufficiently operated upon. In the opposite case the wheels have to do more work than necessary, as they pass many times over the ore which has already been pulverized. It is obvious, then, that the Chilian mill, while it fulfils some of the requisites of a perfect apparatus, falls short of others of the greatest importance. The only process which seems hitherto to have answered all the five conditions necessary to amalgamating apparatus, is what is called at the diggings the miner's assay— a method employed at the mines for determining the value of ores which it is proposed to work. In this process the mortar and pestle are employed. , Mercury is put in the mortar, the ore to be tested is thrown in and covered with hot water, when the operation begins. The pulverization is perfectly effected by the rolling and grinding, or rubbing action of the spherical end of the pestle ; the mercury is kept at the point of crushing in the bottom of the mortar, and is kept heated by the boiling water. Here, then, are all the necessary conditions—perfect pulverization, and instant amalgamation, by pure and hot mercury. On a large scale, the cost of heating sufficient water to attain the result here indicated would, of course, be a great practical difficulty. Some other method of heating would have to be adopted. Those who have seen Mr. Berdan's machine will at once perceive that it embraces every principle of the miner's assay, while it avoids the expensive process of heating water in large quantities. The inventor is a practical and scientific mechanic, whose attention has long been directed to the subject, and the invention has been produced at great labour and expense. In order to obtain all the information bearing upon the subject, Mr. Berdan sent two practical engineers to California, with instructions to study the wants of the miner, and all the appliances which had been adopted to supply them. It was upon a full report of all the facts in the case, that he set about the production of this machine, which really seems to have met the requirements. It performs, at one operation, the pulverizing, washing, and amalgamating of the ore. The construction of the apparatus is simple. It consists of a cast-iron basin, seven feet in diameter, revolving upon an inclined axis or shaft. In this basin are placed two cast-iron balls, the larger one thirty-four inches in diameter, and wei hing two and a half tons, the smaller one twenty-four inches in diameter, and weighing one ton. Under the basin, and attached to and revolving with it, is a furnace of conical form. The whole is hung in a

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strong framework of timber, and receives motion from land, hoise, or steam power, by means of simple cogearing. g The operation is as follows:—Fire is made in the surnace beneath the basin; quicksilver is placed in the basin, and the autiferous ore isthrownin, in lumps ofconsiderable size. The apparatus is then set in motion; the balls, by their gravity, revolving in a direction opposite to that of the busin. The two balls, moving in contact with each other and with the inclined bottom of the basin, receive a spiral as well as a rotary motion—a combination which is found to possess the greatest efficiency in the pulverization of the ore. The ore is brought under the balls, and instantly crushed to an impalpable powder. The crushing is effected, of course, at the point of contact between the large ball and basin, and below the surface of the mercury. Thus, the moulent the gold is disengaged, it comes in contact with pure and heated mercury, which seizes upon and secures it. The refuse powder rises to the surface of the quicksilver, whence it is carried off, in the form of a thin Paste, by a small stream of water, which runs in at the opper side of the basin, and escapes through suitable openings, just below its rim, into a trough placed for the purPo. The tailings, or refuse, may thus be o for analysis is desired. The novel features of the machine are both mechanical * clomical. The arrangement of an inclined revolving *in in connection with balls of corresponding size and "got produces a rolling and grinding motion, which it **lieved has never heretofore been attained. The chenia novelty consists in the heating of the mercury, which has never been attempted on a large scale before. It is to be observed that this machine is not simply a "susher, but that it does all the work necessary to secure the desired product in combination with mercury. It on hos, washes, and amalgamates at one and the same "Potion. The simplicity of its parts, the almost entire avoidance of fiction in its gearing, and the trifling power *I'lined to work it, render it an important addition to mining machinery, and worthy of being subjected to *Y test that practical and scientific men can devise. It * "und that a machine consisting of four basins in one frame, will pulverize, wash, and amalgamate about forty !” of ore, of average hardness, in ten hours, with fifteenhorse power. Any number of basins can be used in one frame, and driven by one main shaft. Thouliarities of this invention do not consist in the of balls and basins; but, 1st,--The inclining of the shatton which the basin revolves, which keeps the mer"to owys at the crushing point, and causes the balls "Yok by gravity. 2nd,-The production of a combined "ling and ginding action by the contact of the balls; **i-The addition of heat to the mercury by means of the sumace below the basin. No machine which does * combine these three peculiarities, can be considered *having a resemblance to Berdan's. This machine—

| Grinds the ore to an impalpable powder. # It amalgamates at the instant of crushing. * Itamalgamates below the surface of the mercury. # I heats the mercury used in amalgamating. 5. It has attached to it an auxiliary machine, which entirely prevents loss of mercury.

This auxiliary machine is called a separator, and is as * in its construction as the principai machine. The **, of the tailings from the large machine pass by * soughs to the funnel at the top of the separator. Thence they descend the contral tube, ind, fijing the hoi. * Arms, pass out in thin sheets through narrow slots at the "loof a large mass of mercury. In passing up ough this mass, all the broken mercury is detained by **utation between it and the mass. The subsidence !' the powder in sufficient quantity to clog the machine *P*nted by the revolving wings, which move just * the surface of the mercury, in a direction opposite "that of the hollow arms, and by their inclined position

constantly urge the contained matters to the top of the vessels, where they escape through a proper exit spout.

DISCUSSION.

The CHAIRMAN said, he was sure they must all feel obliged to Mr. Stansbury for his very interesting paper, and he begged to move a vote of thanks to that gentleman. The vote having been passed, Professor TENNANT being called upon to address the meeting, said, he could not give any information relative to Berdan's machine, not having had an o portunity of witnessing its working, though he had had many invitations to do so. In reference to the observations implying that large quantities of gold were to be found in this country, he was afraid the public mind might be led to believe they were about to have a California or Australia at home. Now there was no instance in which the workings for gold in the British Islands had been ultimately productive. In every case it had been found that it cost 33s, or 40s. to obtain one pound's worth of gold. Some years since, gold was found in the Highlands of Scotland, on the property of the Marquis of Breadalbane, who proposed to work it, until he was assured it would cost from 30s. to 40s. for every sovereign obtained. The condition of the gold in this country, and Australia and California, was very different—in the latter places, nature having been at work for many centuries in decomposing the rocks from which the gold was washed down into the rivers and streams, from which it was comparatively easily obtained. Attempts had been made to produce gold from the quartz, but he was not aware that either in Australia, or California, results had yet been obtained to prove it could be worked at a profit. Mr. Mogrond, of the Poltimore Mining Company, said, after the observations of the last speaker he felt bound to make a few remarks. The Poltimore mines, in Devonshire, had been at work for the last twelve months, and 40 tons of ore had been sent to Messrs. Rawlings and Watson, of St. Helens, near Liverpool, for reduction. The cost had been: In bringing the ore to grass 3s. per ton, freight 17s., and reduction 30s., whilst the produce had been about 50 oz. of gold. Since that time, 120 tons had been sent to the Messrs. Rawlings for reduction, who, after deducting every charge, had sent them a cheque for 170l. or 180l., as the profit. They had since entered into an engagement with Mr. Berdan to erect machines at the mines, where there was an almost unlimited supply of gossan, from which they expected to obtain gold at an expense not exceeding 10s. per ton. They had tested the machines at Mr. Berdan's, in the presence of Mr. John Wilson, of the firm of Rawlings and Watson, when the brown gossan, of which there were specimens in that room, produced 13 dwt. of gold to the ton, and the red gossan 32 dwt.—and Mr. Wilson expressed himself perfectly satisfied with the working—the reduction which, under the system of his firm, would have cost 30s. ton, being made at a comparatively trifling cost. He believed that, in twelve months, they would be in a condition to prove that gold could be most profitably produced in England. There was one circumstance to which he wished to call attention, as having a great effect in discouraging mining operations in England—the right of the Crown to a proportion of all the produce. He trusted, now that free trade was established—the relic of feudal times of the Crown claiming a royalty on all metals produced in the British Islands, would be done away with. . . In reply to questions by the chairman, Mr. Mogford said, they possessed miles of gossan, and some of it lay close to the surface—they also had quartz, but that principally yielded copper. The utmost depth the had yet sunk was 40 fathoms. These mines ... from the massive stone works in them, to have been for. merly worked by the Saxons, as they were certainly not of more modern date. Sir Henry de la Beche had examined their ores, and pronounced favourably upon them. In fact, the only question now to be settled was, whether . could be worked profitably, and of that he had no oubt. Mr. PERREs said there had been many inventions brought from America, which afterwards proved to be English. He maintained that such was the case with regard to Berdan's machine, which he (Mr. P.) had publicly advertised to be an infringement of his patent, and he was about to take legal proceedings against that gentleman to prove his rights. He denied that Berdan's machine would do all that Mr. Stansbury had stated, and maintained that the friction of the balls and pan must be immense. The Chilian mills were not the most perfect, neither were Mr. Berdan's machines, and he would challenge them that they could not do with a dozen pans and balls what he would do with his conical rolling machine—one of which would be ready for experimentalising with in about three weeks. With regard to what Mr. Tennant had said, that gold could not be produced at less than 30s. or 40s. per ton, he was prepared to prove it might be obtained for 5s. per ton, and even, from soft gossan, at 3s.6d. per ton, and he believed the time was not far distant when they would show as good diggings in England as in Australia or California. Professor TENNANT said, it was very necessary, in discussing this question, to distinguish between quartz and gossan. Gossan was decomposed rock, and of course might be reduced at a very small cost. They might, however—souncertain was it—take upone portion, one-fifth of which should be gold, whilst the next and immediately adjoining portion did not contain a particle of the precious ore. It was generally found in threads, and he had seen Fo of Australian ore in which the irregularities he ad alluded to were peculiarly marked. Gossan, as understood in Devonshire and Cornwall, was a very indefinite term, something like mundic—a term there applied to all yellow ore. Thus he had asked a mining captain, “What is this 2" and was informed mundic, the substance consisting principally of iron; a similar answer had been given him respecting ore containing copper pyrites, and again upon some containing arsenic and iron pyrites. The CHAIRMAN said, that in the mining districts parties who were called streamers were in the habit of collecting gold in quills which they corked up and sold to the jewellers. Professor TENNANT was aware of that fact, and that the gold was generally purer than the standard. The same system was adopted on the coast of Africa, but there they were also in the habit of filing up brass kettles and mixing the filings with the gold, selling it all for gold dust. The imposition, however, might easily be discovered by nitric acid, which would dissolve the brass without touching the gold. Mr. ColeMAN did not profess to be a scientific man, and, without wishing to call in question the good taste of Mr. Perkes' observation with regard to Mr. Berdan's machine, he might observe that he had seen a correspondence between the gentlemen which seemed to prove to him that Mr. Perkes had but a poor case, or he would have been more active in taking proceedings against Mr. Berdan. With reference to what had been said, that they were not to suppose that they had found a California or Australia in Great Britain, he might observe he had just returned from Wales, where he had been to inspect the Cwmheisian Mines. He had there seen large quantities of valuable quartz rock, some of which he had tested since he came to London, when the gold was found to be equal to 3 oz. rton. He believed he was right in saying that the Sir John del Rey Company, which was paying a dividend of twenty-five per cent, and its shares being quoted at 40l. for 15l. paid, had never produced more than half an ounce to the ton; and a report of the Brazilian Mining Company, in the last Mining Journal, showed that their average produce was less than 2 dwts. to the ton, and yet he was assured by a gentleman connected with that company, that they were quite satisfied it would amply pay them. He thought, looking at these facts, that there was no rea

son to doubt gold might be obtained and advantageously worked in this country. Mr. Mogford wished to observe, in reference to what Mr. Perkes had said of the inefficiency of Berdan's machine, that he had offered to construct those machines for their Company at 600l. less than Mr. Berdan. Mr. PERREs might observe, in reference to what had been stated about his correspondence with Mr. Berdan, that the only reason an injunction had not yet been applied for was the fact that some little matters were overclaimed in their specification; as soon as these had been disclaimed proceedings would go on. Mr. WoolMER was quite sure the meeting had nothing to do with the law of the question now before them. He attended there as connected with the Arundel mines in Devonshire, the “mundic” from which they had every reason to believe contained large quantities of gold. He now begged to put at the disposal, either of Mr. Perkes or Mr. Berdan, 5 tons of the mundic, to be tried as to its value under any scientific inspection that might be thought desirable. He was informed there was also a large quantity of valuable gossan at the mine, which might open up an important sphere of industry in Great Britain, should the results prove equal to expectation. Should either or both the gentlemen he had named be desirous of trying an experiment on the value of the ore, 5 tons should be placed at his disposal for the purpose, free of expense; and he believed that that quantity would be generally considered sufficient to give a fair example of what they might expect from the mine. Mr. PERREs would at once accept the offer. Mr. John CALvent said, since his return from Australia, he had devoted his energies to seeing whether gold was not to be found in England; as he thought, from its geological formation, there was every reason to believe it was peculiarly rich in gold. Indeed, he had tested upwards of 300 specimens, and he had no hesitation in saying that richer was not to be found in the world. They were too much in the habit of thinking that gold could only be found in hot countries, and Englishmen would not believe that it could be found in the country in which they lived. . In the antipodes they searched diligently for their riches, which was not the case in England. He had travelled very extensively, and he had no hesitation in saying that there was no country so rich in gold as England; and he believed that much quartz would shortly be found, which would not only yield half an ounce, but five or six ounces a ton. He expected, in a very short time, to see these riches developed to an enormous extent; the only disliculty in its production having been hitherto the crude method of working adopted. Mr. HARRY CHESTER did not wish to give any opinion on the merits of the invention brought before them that evening by Mr. Stansbury, or on the probabilities of large fortunes being obtained from gold discoveries in England. They had given a vote of thanks to Mr. Stansbury for his paper, but that did not pledge the Society of Arts to an approval of the sentiments expressed in it. . Neither was the Society responsible for observations made in that room, as they held an open session, in which Inany gentlemen were allowed to express their opinions who had no further connection with the Society than that of taking an interest in the discussion of the evening. The o for which he rose was to suggest that Mr. Beran’s invention should be submitted to the Standing Committee of the Society, “On Mining, Quarrying, Metallurgical Operations and Mineral Products,” to report upon its value. That committee consisted of Professor Ansted, Mr. Wm. Bird, and Mr. Thos. Sopwith. They would make a full report upon the subject, and if the invention possessed merits, the results of the experiments would prove thcm ; but if it was a failure the sooner the public mind was disabused on the subject the better. Mr. STANsbury, speaking on the part of Mr. Berdan, had no hesitation in saying that he would be most happy to have the machine subjected to any test the Society could put it to. He would say further, that the fullest inuity was courted. They had from the first placed the michine under the control of any persons or companies choosing to use it, either bringing their own quicksilver or using that upon the premises, no party connected with the machine, even for a moment, interfering with the working. Fifty or sixty experiments had been made by companies in the W. sence of scientific men, and he believed they had all proved satisfactory—at all events, they had heard nothing to the contrary. Indeed, in no instance had they ever discovered any gold in the tailings excepting once, and that was in a case were the gold had been reduced to a fine powder before being placed in the amalgamator; not had there been any mercury found in them, since the introduction of the separator. The experiments with the amalgamator had been made with 700, 1000, or 2000lbs. at a time; and, surely, the results for such quantities must be more satisfactory than those from the mere thimblesuls used by the general assayists. And yet, from the report upon these thimblefuls of dust, produced from the Powdered ore, were large and important companies continually established.

The SECRETARY announced that at the next meeting, on the 30th of November, a paper would be read “On the Consumption of Smoke,” by Mr. A. Fraser.

GARANCINE AND THE JUICE OF THE MUDI)AR.

At the meeting of the Society on Wednesday oveling, a sample of garancine, or the colouring latter of the munjeet or Indian Madder, and also a block of the juice of the ak or middar Phill, which it is proposed to use as a substitute for gutta percha, were exhibited. Specimens of the raw fibre of the middar plant, of raw and Mached thread, of twisted and coarse twine, and of ord and rope manufactured from this fibre, Were also shown. Full particulars respecting those substances will be found in Vol. I. of the Woosal, page 597.

NEW ZEALAND FLAX. Th: Council have received from the New Zealand Society the one ton of Phormium Tenar, or Now Zealand Flax, mentioned in a previous "olor of the Jovisai (ride Vol. I. page 533), which has been cleansed in rather an inferior *her to the usual mode, and has had much less labout bestowed upon it than native-dressed flax. Theolject of the New Zealand Society in sending to sample, is to enable experiments to be made, * * view to the introduction and application **h machinery and processes as might lead to "Provements in the preparation of the flax, so as "older it fit for exportation. The New Zeaol Society has placed in the hands of the "oil a draft for 50 guineas, which they are "long should be awarded to any person who Yohinish them with modes of operation, mo* and specifications of machinery, by which o * may be dressed at a cost not exceeding * Per ton, (this price to prepare the flax as a " material), reckoning the wages of an ordi

nary labourer at 4s. per diem, and of artisans at 6s. to 6s. 6d. The machine to be of two kinds; one analogous to the old spinning wheel, that may be used in every cottage or shepherd's hut, and the other suitable for more extensive operations.

BIRMINGHAM AND MIDLAND INSTITUTE FOR INDUSTRIAL EDUCATION. It was announced in the columns of “The Times,” as a great fact, during the progress of the discussion on the Corn Laws, that Manchester had in one evening contributed to help forward the movement £70,000. It is also a great fact that on the evening of Thursday last, the 17th of November, upwards of 5,000 people filled the Town Hall of Birmingham, to listen to four hours' talk about science and art, the necessity which existed for Industrial Education, and the means which were about to be afforded for forwarding the same. Captain Tindal occupied the chair, and there were present not a few country gentlemen, clergymen, leading manufacturers, and useful members of the community, known for their attachment to the rogress of imperial education and the diffusion of useful ...i. among the people. The chairman ão the proceedings, introducing to the meeting Mr. Henry Cole, one of the Secretaries to the Department of Practical Art and Science, and regretting the absence of Dr. Lyon Playfair, whose letter of apology he read. The Chairman said:—It is proposed that the Institute shall consist of two departments; one a General Department; the other, Schools of Industrial Science. Under the former head will be embraced—1st, The I.iterary Branch, comprising general and reference Libraries, Reading Rooms, accommodation, as far as may be practi. <able, for the Literary Societies of the town, and Lectures on subjects kindred to this branch; 2nd, Museums ; 3rd, a Collection of Mining Records ; 4th, Lectures on general scientific subjects : 5th, Periodical Meetings for the reading and discussion of original communications, upon the plan as the sections of the British Association; and 6th, a Gallery of Fine Arts, for the reception of examples of Painting aud Sculpture. The second department is even of more importance, inasmuch as it has reference to the scientific instruction of artisans in the principles of their daily avocations. The other department will be a School of Industrial Science, the members of which will be provided with systematic lectures and class instruction in the various branches of science, with especial reference to their particular occupations; and will also partake of the most important, advantages of the general department. The lectures will include Chemistry, as applied to the various manufactures, and agriculture, mechanies, metallurgy, mineralogy, and geology, ventilation of mines, and mining engineering. The Institute will occupy an intermediate position between the ordinary school education, and that of the Queen's College. It will provide for the working man a knowledge of the laws of these Sciences

which enter into his every day employment, and thereby

substitute scientific knowledge for empiricism and practice. The Town Council had granted them a site—it remained for the public themselves to say, whether the scheme was to be carried out in all its entirety, or whether they would allow any little petty parsimonious feeling to interfere with the erection of a, building, worthy of the purposes to which it was to be devoted, Sir Robert Peel in proposing the first resolution — “That it is essential to the full development of the resources of this district, rich in its mines and manufactures, that ample provision be made for the instruction of the industrial classes in the principles of science and art,” said, that Birmingham had a position to maintain, which could only be done by the most earnest efforts, and by providing the means of Industrial Education in such an

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