Volume 11 (1865) (424 pages)

The lining and Scientific Lress, 387 respect, that he has made “ anmerons experiments,” aad invented a method for desul phurizing ores which he nbandoned as impracticable, and heneo, logically, he is the better able, using his own words, “to point out what I consider to be an effectonl method for the purpose.” Proceeding from this stand-point of nbility, “to point out an effectual method ” eo ingenionsly established, he takes np “ the common method of desulphiurizing the minerul,” viz., ronsting it ia a finely divided state in a reverberating far nace. ‘fo this method he gives no qnnrter, notwithstanding its adoption and use by the most praeticnl, econowwical, und learned inetullnrgists of this eonntry and Europe, during the last thirty yeare. In this caso the condemnntion rests in the tact (whieh he says is nlmost uuiversally admitted), that from twenty to eighty per cent. of tho precious metnls is carried off meehanically. Thot a sensible loss occurs in thie wny is ecrtainly not denied ; but that even tbis miuimoni of loss is reached in the most ordinury working of the reverheratory furnace is execedingly questionablo. But even were this so, seurcely uuy prudent niannger is so ignorant of the fact, nud so indifferent to the loss, he thnt What it may, that he does not guard against it by the use of condensing ehambere, which are as eommon to the reverberntory furunee ns the fire-bridgeand grate-bars. Up to the present time ao better method has heen found wits which to replace the reverberatory form of furnaee, the objections to which are of a serious character, and mainly referable to the expense of building and kecping tbem in repair, the tronble and cost of working the ore properly, and the constaat dread of careless and indiffereat workmen, apon whom the eaccessful roasting of the ore ehiefly depends. The chloriantioa method in reverberatory farnaces meets with the same disapproval on the same grounds; yet, the lamented Plattner used this form of chloriaating furnace for ores which contained only two hundred graing of gold to the toa. At Mansfield, Freiburg, at Swansea, and many other localities, thousands of toas of ore are yearly roasted ia such faraaces. The Augustin process, that of Ziervogel and that of Von Patera, oll invented by emiaent ~ metallurgieal® chemists, are successfully carried out in these condemned furnacee, and certainly their self-complacency will be somewhat distarbed, if at this late day they are to be informed that their loss of metal runs from tweaty to eighty per cent. A cheaper mode of working, aad a less expensive structure, calculated to accomplish the same ends, is greatly needed, more especiully for the gold sulphurets of California; aad with this view, many new contrivances or processes have beea offered. To these the author of the article in question-next devotes himself, with a vigor which must have aequired much of its eaergy from the successfnl overthrow of all the old inethods. He etyles these, “ inventioas,” “in the shape of furnaces,” and says of them: “ But Lan not aware thal any of them have yet answered the tations of the inventors.’ ‘Thie is truly amiable ia the writer, to throw tbe acknowledgmeat of the failures oa the inveutors themselves. Now, the truth is, the iaveators are the very pereoas who insist that their inventions do aaswer their expectations, aad “thnt’s what's the matter.” If it were not so, the author of the above remark would not deem it aecessary to demolish the zew as well as the old, in order to get a foot-hold for the new invention, which he preseatly commends as the effectual method. If, however, he meaas that the expectations of the inventors have been dieappoiuted, inasmach as their plans are not euccessfully introduced, the same difficulty has beea experienced by the inventor of that which receives his saactioa as “ the effectual method ;” eince, to the knowledge of the writer of this article, Mr. White's revolviag cylinder was exhibited to the public at Newark, New Jersey, eighteea moaths ago, and only a few days, since an advertisement for capital to erect a working furnace appeared in thie journal. The “ God aad Silver Separating Company's Furnace,” and all akia to it,are aow eubjected to the crucible test of the metallurgical chemist, aad pronounced worthless, with a phew! “ How can steam, superheated or not, be made to permeate a solid mass of ore, be the construction of the frrnace what it may ?” Let us examiue very briefly the mode by which this conclusioa is scieatifically arrived at. This mode is mainly commended to our coafidence, from the cireumstaace of his being requested to examine the performance of this furnaee (using hie own words), “in my professional capaeity, the result of which may be interesting to many of your readers.”(?) After stating -generally the manner of treatmeut to which the ore was suhjected, he gives several reports of the results, three of which are as follows : “ First —.Assay of the crude sulphurete: Gold, $301.72 ; (this ehould he $391.72, evidently a typographieal error ;) silver, $3.76— $395.48 per ton.” “ Third. — Assay of mass nfter treatment : Gold, $329.50; silver, $3.02 —$332.52 per ton.” “ Sixth.— Assay tailings, $146.12 per ton ;” from which, he saye, “I conelnde that nearly sixteen per eent. of the precious metals was lost during the treatment; that the mineral was desulphurized to the extent of fifty-five per cent.; that fifty-two per cent. ($205.12 per ton) of the preeious metals was extracted by omalgamntion, aud that thirty-two per cent. was left in the tailings.” These eouelusions are not as a whole justified by the figures, ond, in oue respeet, are manifestly unfair to the performnnce of the furnace. ‘The desulphurization was evidently incomplete, ns the metnl left iu the tailings showed, and this may be a radical defect of the furnace; but ns to the loss during treatnient, (the vital point in the of, nnd now equally so in the new), the facts do uot warrant the eoaclasion. ‘Iho assay from the crune ore mnst hnve been made from a lot or lump of ore necessarily different trom thnt mass from whieh tho third nssay was mnde. ‘The last was no mass mixed—tbe first a lump or lumps, perhaps fairly takea; but not aecessarily nor probably representing the eame mass ns that from which the third nssny wos mnde. Lenee, the difference of $62.96, or nearly sixteen per cent., would be nothing uausnal in itself. But aside from this, add the fixed, positive data obtained by the extractioa of $205.12 to that shown by assay, remaining ia the tailings, and we have $205.124+146.12—$351.24. Now, enbtracting this last snm from the assay of the erudo sulphurets—$395.48=351.24—=44.24, or not quite twelve per cent. of loss, assuming that the ore from whieh the first assay was absolutely a fair representative of, the mass subjected to the treatment in the furnace, and afterwards by amalgamation. ‘This assumption cannot be maiutained, and hence the loss might be rightly eet down as merely nominal, especially when it is coasidered that a small logs in separating the amalgam might entirely account for the eeeming loss. The unfairness of the conclusion ae to the loss is still more strongly shown, by observing that the aggregate of the extraction, and that lelt in the tailings, is @ ‘greater sum thaa wae found ia the mags by his third nssay !! The fling at furnaces of aay construction, whether asiug steam, superheated or saturated, is not worthy of a scientific iavestigator. It involves the ackaowledement of ignorance, aad ie aot supported by anything preceding or foilowing ia the article by which the unlearned iu such matters can auswer the question. What is meant by steam “permeating a mass of stone?” If it is meapt that steam will not pass through the iaterstices of the mass, the suggestion is simply absurd. If it is meant, as it probably was jatended, that steam eannot eater the mass of the eingle stones or lumps of ore, it betrays dowaright ignorance to intimate that snch an effect is claimed or even desired. Limestoae has beea decarboaized for many years by the use of steam in coajunctiga with heat, and it has yet to be intimated by any metallurgical chemist that the steam eatcrs (‘ permeates”) each individual stoae, and serves a writ of ejectment on the carbonic acid. Yet, for decomposing carbonate of lime, it is recognized asa most efficient agent. The mechanical as well as the chemical effects of steam are well understood by all men who caré to investigate, with the view of arriving at facts, rather than to build up or cast dowaa particular inveatioa. The point of the fling, however, does not wholly rest in the steam; the author means to disparage the attempt to desulpburize ore in tbe lump, since his effectaal method requires it to be crushed tolerably fine. Possibly: he is uot aware that this has beea doae with oree quite as difficult to treat as the sulphurets of UCalifornia. , Cianibar contains sulphur aad arseaic in considerable abuadnnce ; the ore is compact, it is put in the furnaces ia the lamps—the sulphur and arseaic are mostly driven off as closely as the mercury. Carbonate of lime, as above mentioned, is dease, compact, and not combustible in the slightest degree. It is pnt in kilns, in large lumps, and decarboaized. ‘I'he ores in question nore variously composed of sulphur, arsenic and antimoay, associated with the metals. These minerals are combustible—that is, they ignite—and hence the vapore must escape if proper conditions are maintaiaed. ‘I’be oxyzen 1 of the atmosphere can readily eater where sueh vapors escape, producing the oxidation desired. ta theory, therefore, as well asin practice, the desu!pburization of ores in the lump offer less difficulty than the decarhonizing of limestone, and the desilvering of cinnabar, provided the requisite conditione caa be mzintained in the former case as well as in the latter. With the view of employing and ma‘ataising tbese conditions, many parties are earnestly at work, and their success or failure will aot be materially impeded or aided by any ill-digested remarks, however emphasized by scieatific authority. A Sropexr or Mrratiureican CaeMistry. (Wrilten for lhe Mining and Sclenilfic Press} The Problem of Gold and Silver Extraction-A General Review-—-No, XX. RY PROF. L. LANSZWEERT. [Conelusion.) For the application of tho processes in my lnst nomber, no general rule con be giveu, as they cna he economically and praetically employed only onder peeulinr circnmstances. It is, unfortunately, the habit of the more cyinical ond less practical of men to ridicule all the soculled scientific proeesses which may be proposed, cither in addreeses or written papers ; also, all mention of any new invention thut may lve been suceessfully curried out. Some will, no doubt, say, in reply to these remarks: We do not want to know whut other people are doing ; we can mannge our own businese very well. To such it ie only aeeessary to say, may you grow wiser ns you grow older, for to upset the conceit whieh prompts euch a remark ia, as experience teaches, quite impossible. Those that seorn sound advice, whero often niost needed, are the greatest. drawbacks to useful science ; ns some men are go vain of their worldly wisdom as to imagine thnt ao better measures ean he adopted than theit owa; hence they detest aay hiats from outsiders. Others, again, are eonstaatly complaining, or asking for advice, yet seldom accept the remedies offered, beeause they cannot perceive their practical utility ; while those who are more sanguine oftea jurop at conclusioas that are only to be coademaed in their turn, simply beeause the real scieace of chemicnl metallurgy is so vaguely uaderstood, and which aever can be otherwise while the very elements which constitute each metal aro erroneously described. Nevertheless, it would he far more profitable ia the ead for any gold’and silver company to truly ascertain both the real aature of their different ores, and the best means of treating the eame; as the mere quantitative analysis of aay particular ore are not always sufficient proof that the Therefore, evea graated that any certain lode will, oa annlysis, yield at the rate of, eay, 1 oz. per ton, aad yet whea opeaed aad operated upon oa a large senle, but a few graias can—be collected. Now, whose fault is that? Js it that of the maaager or amalgamator, who not only worked upon different ores from the assnyer, but worked oa very different priaciples, often oa none, or at best oa some knowa formula, that might be profitable to eome kiude of ore, yet not for others. Heace, every eort of ore should aot only be analyzed separately, but the very compoaeats of their matrices ; as it often depende upoa whether the general base is silica, calcia, alumina, and what kind of pyrites, or what not, may be associated. In most mines, the very dirt itself differs; as there are earths in California aot found ia Europe, and so are their metals as well ae minerals. However, the main qaestioa, ia most cases, to arrive at is, the profit and loss; thea precious metals are where the ores sought for may be obtained at the least cost. Would it not be far more natural to first assort the earths to be operated upon, even if all were wished to go through different processes. good thing is worth doing, is it aot worth while to do it well from the firet?” ‘Then why not turn every useful item to some advantage, purticularly where nature supplies the raw material as cheap as dirt. Of every country possessing miacral territory, as of every person in the possession of miaeral property, the duty is clearly defiaed. The hoad to the letter imposes on the community and on the individual so endowed the industry to explore and work. There is no evading the responsibility ; whatever the surface cultivatioa, room must be accorded to the miner tor his operations, otherwise the value’ of property in its fulness and reality cannot he reached ; it will remain inert art consequently suffer in their most important interest. It caanot he admitted that Lord Bacon was even wise in his geaeration, when he hade the world aot to “ moil” for richee underground ; experience, at the present time, explodes sueh pbilosophy, and with eye of statd speculation and unwavering hand poiuts to the fact, that the balance of labor betweea agriculture and mechanics could not he prosperously sustained in this, or ia any other country, where mine works were to be discourage or neglected, and impressively directs the energies of every people to such, as constituting an indnstrial umines will pay for working ia the ordiaary way. . There is aa old maxim that saye, “ If aay . . and useless to a serioas extent, aad science aad, ultimately on to fortune., Short-sighted, traly, is the poliey which would restrain a seetion of people, even in anew settlement, from this nvailable means of advaneement. ‘The toil of the husbandmnn nnd the tending of the feeder ol the flocks nnd herds, are not the only inapirations of intelligenee to which people in a new country should hold themselves aceessible. Wine und cattle, vegetables nnd eereals, are, uo doubt, profitable, aud dot the landseape attraetively, but the nomad and the culturer would ill serve the world nt ite aetual eivilized age, were there no * dark and dangerous ie and traps of mines and mining,” with the ong, smoking ehimneye nnd the ponderous ny = chinery to whieh they ininister in their nutural imposing positions over the face of the land. After providing for the wante of animul life, the inineral resources of n settlement nierit the earliest testing ; nnd this attended to, tiine will be faken hy the forelock to the promoting of thnt eomimeree and manufacture whereby the purposes of eivilization ure hest served and ite priueiples universally utilized. So sel!-evident a requirement in the sphere of human induatry needs no lengthened discussion to prove its worth, and reeommiend it as materially important. The “knights of the pick” are not mere Quixotes. "They have their uses, and those usee are, at the present day, more than ever great and acknowledged faets. Ina word, those ertuut explorers are the first rank servitors of the commonwealth. They are those who open the little rivulets whose nuited waters make up the great streum of gold and silver, whoee constant flow is an absolute aecessity. to the successful prosecution of those great sehemes of ninnoulaeture and ecommerce, whieh, during the pust decade anda half, has so immensely advanced the mnterial progress of the eivilized world. Witbout their aid the smoke of our foundries and furaaces would no more be seea; the iroa horse aad his track would be dormant and dead in the bosom of mother earth ; the thanders of our war fleeta would be hushed ia silence, and our merchant marine would dwindle away to pigmy proportions. In concluding, for the present, this eeries of articles upon n subject so absolutely inexhaustive, aust rely upon the indulgeace of the readers of these papers forany imperfectinne or omissions which may have beea aotieed. My aim has been fulfilled if I have succeeded in pointing out certaia renctione which may be euggestive of further progress; or if I have beea beneficial in any way ia attracting attentioa tn the necessity and importaace of a more thorough and scientific treatment of the oree of the precioas metals, ia mining, upon the Pacific Coast. MINERS’ MASS MEETING AT SUMMIT CITY, EXCELSIOR DISTRICT. On the 8th instant, a lnrge and enthusiastic meetiag of the minere and citizeas coavened at Summit City, pursuaat. to a previous adjourament. J. A. Brumsey, Chairman. : Mr. Brumsey briefly stated the objecte of the meetiag to be to elect delegates to the Miners’ State Coaveatioa, to be held at Sacramento during tho winter of 1865-6. Mr. B. was followed by Mr. Thoe. Haanah, who spoke of the preat aecessity of a general Minere Convention oa this coast, and showed the benefits and advaatagee that would, doubtless, be derived from such aa orgaaization, and urged upon the gentlemen present the propriety of immediately taking eteps to show that they fully endorsed the call for eaid Conveation. The following resolutioas were adopted : Resolved, That we endorse the call of the Mining ana Scipntiric Press for a Miners’ Stnte. Convention, to be held at Sacramento, January 17th, 1865. Resolved, That a delegatioa of five menibers be chosen to represent, this mining district at said Convention, to he chosen as followe: Three delegates from Summit City, oae from Enterprise, and oae from old Mau Mountain and Baltimore. esolved, That ao general law can be made to fully meet the wants of the various mining districts ia this State. But we recommend the adoption of such general laws as may be applicable to the various mining districts in the State, reserving to the districts theniselves the right to make sueh ndditional regulatioae as may.be aecessary ia each individual case. Resolved, That the delegates elected from this district ehall attend the Miners’ State Coaventich, whenever said Conventson shall meet, whether under the late eall of the Mining ana Screntiric Press, or any euhsequent call that may be made. © The following-named gentlemea were elected as delegates : J. A. Brumsey, Thos. Hanaah, J. R. Stewart, delegates from Summit City. ; J. H. Fitzgerald, delegate {rom Eaterprise. F. W. Mitchell, delegate from Old Man Mountain and Baltimore. ; The meeting then adjouraed, subject to the pursuit which, if perseveringly followed, leads '.call of the Chairmaa.

The lining and Scientific Lress, 387 respect, that he has made “ anmerons experiments,” aad invented a method for desul phurizing ores which he nbandoned as impracticable, and heneo, logically, he is the better able, using his own words, “to point out what I consider to be an effectonl method for the purpose.” Proceeding from this stand-point of nbility, “to point out an effectual method ” eo ingenionsly established, he takes np “ the common method of desulphiurizing the minerul,” viz., ronsting it ia a finely divided state in a reverberating far nace. ‘fo this method he gives no qnnrter, notwithstanding its adoption and use by the most praeticnl, econowwical, und learned inetullnrgists of this eonntry and Europe, during the last thirty yeare. In this caso the condemnntion rests in the tact (whieh he says is nlmost uuiversally admitted), that from twenty to eighty per cent. of tho precious metnls is carried off meehanically. Thot a sensible loss occurs in thie wny is ecrtainly not denied ; but that even tbis miuimoni of loss is reached in the most ordinury working of the reverheratory furnace is execedingly questionablo. But even were this so, seurcely uuy prudent niannger is so ignorant of the fact, nud so indifferent to the loss, he thnt What it may, that he does not guard against it by the use of condensing ehambere, which are as eommon to the reverberntory furunee ns the fire-bridgeand grate-bars. Up to the present time ao better method has heen found wits which to replace the reverberatory form of furnaee, the objections to which are of a serious character, and mainly referable to the expense of building and kecping tbem in repair, the tronble and cost of working the ore properly, and the constaat dread of careless and indiffereat workmen, apon whom the eaccessful roasting of the ore ehiefly depends. The chloriantioa method in reverberatory farnaces meets with the same disapproval on the same grounds; yet, the lamented Plattner used this form of chloriaating furnace for ores which contained only two hundred graing of gold to the toa. At Mansfield, Freiburg, at Swansea, and many other localities, thousands of toas of ore are yearly roasted ia such faraaces. The Augustin process, that of Ziervogel and that of Von Patera, oll invented by emiaent ~ metallurgieal® chemists, are successfully carried out in these condemned furnacee, and certainly their self-complacency will be somewhat distarbed, if at this late day they are to be informed that their loss of metal runs from tweaty to eighty per cent. A cheaper mode of working, aad a less expensive structure, calculated to accomplish the same ends, is greatly needed, more especiully for the gold sulphurets of California; aad with this view, many new contrivances or processes have beea offered. To these the author of the article in question-next devotes himself, with a vigor which must have aequired much of its eaergy from the successfnl overthrow of all the old inethods. He etyles these, “ inventioas,” “in the shape of furnaces,” and says of them: “ But Lan not aware thal any of them have yet answered the tations of the inventors.’ ‘Thie is truly amiable ia the writer, to throw tbe acknowledgmeat of the failures oa the inveutors themselves. Now, the truth is, the iaveators are the very pereoas who insist that their inventions do aaswer their expectations, aad “thnt’s what's the matter.” If it were not so, the author of the above remark would not deem it aecessary to demolish the zew as well as the old, in order to get a foot-hold for the new invention, which he preseatly commends as the effectual method. If, however, he meaas that the expectations of the inventors have been dieappoiuted, inasmach as their plans are not euccessfully introduced, the same difficulty has beea experienced by the inventor of that which receives his saactioa as “ the effectual method ;” eince, to the knowledge of the writer of this article, Mr. White's revolviag cylinder was exhibited to the public at Newark, New Jersey, eighteea moaths ago, and only a few days, since an advertisement for capital to erect a working furnace appeared in thie journal. The “ God aad Silver Separating Company's Furnace,” and all akia to it,are aow eubjected to the crucible test of the metallurgical chemist, aad pronounced worthless, with a phew! “ How can steam, superheated or not, be made to permeate a solid mass of ore, be the construction of the frrnace what it may ?” Let us examiue very briefly the mode by which this conclusioa is scieatifically arrived at. This mode is mainly commended to our coafidence, from the cireumstaace of his being requested to examine the performance of this furnaee (using hie own words), “in my professional capaeity, the result of which may be interesting to many of your readers.”(?) After stating -generally the manner of treatmeut to which the ore was suhjected, he gives several reports of the results, three of which are as follows : “ First —.Assay of the crude sulphurete: Gold, $301.72 ; (this ehould he $391.72, evidently a typographieal error ;) silver, $3.76— $395.48 per ton.” “ Third. — Assay of mass nfter treatment : Gold, $329.50; silver, $3.02 —$332.52 per ton.” “ Sixth.— Assay tailings, $146.12 per ton ;” from which, he saye, “I conelnde that nearly sixteen per eent. of the precious metals was lost during the treatment; that the mineral was desulphurized to the extent of fifty-five per cent.; that fifty-two per cent. ($205.12 per ton) of the preeious metals was extracted by omalgamntion, aud that thirty-two per cent. was left in the tailings.” These eouelusions are not as a whole justified by the figures, ond, in oue respeet, are manifestly unfair to the performnnce of the furnace. ‘The desulphurization was evidently incomplete, ns the metnl left iu the tailings showed, and this may be a radical defect of the furnace; but ns to the loss during treatnient, (the vital point in the of, nnd now equally so in the new), the facts do uot warrant the eoaclasion. ‘Iho assay from the crune ore mnst hnve been made from a lot or lump of ore necessarily different trom thnt mass from whieh tho third nssay was mnde. ‘The last was no mass mixed—tbe first a lump or lumps, perhaps fairly takea; but not aecessarily nor probably representing the eame mass ns that from which the third nssny wos mnde. Lenee, the difference of $62.96, or nearly sixteen per cent., would be nothing uausnal in itself. But aside from this, add the fixed, positive data obtained by the extractioa of $205.12 to that shown by assay, remaining ia the tailings, and we have $205.124+146.12—$351.24. Now, enbtracting this last snm from the assay of the erudo sulphurets—$395.48=351.24—=44.24, or not quite twelve per cent. of loss, assuming that the ore from whieh the first assay was absolutely a fair representative of, the mass subjected to the treatment in the furnace, and afterwards by amalgamation. ‘This assumption cannot be maiutained, and hence the loss might be rightly eet down as merely nominal, especially when it is coasidered that a small logs in separating the amalgam might entirely account for the eeeming loss. The unfairness of the conclusion ae to the loss is still more strongly shown, by observing that the aggregate of the extraction, and that lelt in the tailings, is @ ‘greater sum thaa wae found ia the mags by his third nssay !! The fling at furnaces of aay construction, whether asiug steam, superheated or saturated, is not worthy of a scientific iavestigator. It involves the ackaowledement of ignorance, aad ie aot supported by anything preceding or foilowing ia the article by which the unlearned iu such matters can auswer the question. What is meant by steam “permeating a mass of stone?” If it is meapt that steam will not pass through the iaterstices of the mass, the suggestion is simply absurd. If it is meant, as it probably was jatended, that steam eannot eater the mass of the eingle stones or lumps of ore, it betrays dowaright ignorance to intimate that snch an effect is claimed or even desired. Limestoae has beea decarboaized for many years by the use of steam in coajunctiga with heat, and it has yet to be intimated by any metallurgical chemist that the steam eatcrs (‘ permeates”) each individual stoae, and serves a writ of ejectment on the carbonic acid. Yet, for decomposing carbonate of lime, it is recognized asa most efficient agent. The mechanical as well as the chemical effects of steam are well understood by all men who caré to investigate, with the view of arriving at facts, rather than to build up or cast dowaa particular inveatioa. The point of the fling, however, does not wholly rest in the steam; the author means to disparage the attempt to desulpburize ore in tbe lump, since his effectaal method requires it to be crushed tolerably fine. Possibly: he is uot aware that this has beea doae with oree quite as difficult to treat as the sulphurets of UCalifornia. , Cianibar contains sulphur aad arseaic in considerable abuadnnce ; the ore is compact, it is put in the furnaces ia the lamps—the sulphur and arseaic are mostly driven off as closely as the mercury. Carbonate of lime, as above mentioned, is dease, compact, and not combustible in the slightest degree. It is pnt in kilns, in large lumps, and decarboaized. ‘I'he ores in question nore variously composed of sulphur, arsenic and antimoay, associated with the metals. These minerals are combustible—that is, they ignite—and hence the vapore must escape if proper conditions are maintaiaed. ‘I’be oxyzen 1 of the atmosphere can readily eater where sueh vapors escape, producing the oxidation desired. ta theory, therefore, as well asin practice, the desu!pburization of ores in the lump offer less difficulty than the decarhonizing of limestone, and the desilvering of cinnabar, provided the requisite conditione caa be mzintained in the former case as well as in the latter. With the view of employing and ma‘ataising tbese conditions, many parties are earnestly at work, and their success or failure will aot be

materially impeded or aided by any ill-digested remarks, however emphasized by scieatific authority. A Sropexr or Mrratiureican CaeMistry. (Wrilten for lhe Mining and Sclenilfic Press} The Problem of Gold and Silver Extraction-A General Review-—-No, XX. RY PROF. L. LANSZWEERT. [Conelusion.) For the application of tho processes in my lnst nomber, no general rule con be giveu, as they cna he economically and praetically employed only onder peeulinr circnmstances. It is, unfortunately, the habit of the more cyinical ond less practical of men to ridicule all the soculled scientific proeesses which may be proposed, cither in addreeses or written papers ; also, all mention of any new invention thut may lve been suceessfully curried out. Some will, no doubt, say, in reply to these remarks: We do not want to know whut other people are doing ; we can mannge our own businese very well. To such it ie only aeeessary to say, may you grow wiser ns you grow older, for to upset the conceit whieh prompts euch a remark ia, as experience teaches, quite impossible. Those that seorn sound advice, whero often niost needed, are the greatest. drawbacks to useful science ; ns some men are go vain of their worldly wisdom as to imagine thnt ao better measures ean he adopted than theit owa; hence they detest aay hiats from outsiders. Others, again, are eonstaatly complaining, or asking for advice, yet seldom accept the remedies offered, beeause they cannot perceive their practical utility ; while those who are more sanguine oftea jurop at conclusioas that are only to be coademaed in their turn, simply beeause the real scieace of chemicnl metallurgy is so vaguely uaderstood, and which aever can be otherwise while the very elements which constitute each metal aro erroneously described. Nevertheless, it would he far more profitable ia the ead for any gold’and silver company to truly ascertain both the real aature of their different ores, and the best means of treating the eame; as the mere quantitative analysis of aay particular ore are not always sufficient proof that the Therefore, evea graated that any certain lode will, oa annlysis, yield at the rate of, eay, 1 oz. per ton, aad yet whea opeaed aad operated upon oa a large senle, but a few graias can—be collected. Now, whose fault is that? Js it that of the maaager or amalgamator, who not only worked upon different ores from the assnyer, but worked oa very different priaciples, often oa none, or at best oa some knowa formula, that might be profitable to eome kiude of ore, yet not for others. Heace, every eort of ore should aot only be analyzed separately, but the very compoaeats of their matrices ; as it often depende upoa whether the general base is silica, calcia, alumina, and what kind of pyrites, or what not, may be associated. In most mines, the very dirt itself differs; as there are earths in California aot found ia Europe, and so are their metals as well ae minerals. However, the main qaestioa, ia most cases, to arrive at is, the profit and loss; thea precious metals are where the ores sought for may be obtained at the least cost. Would it not be far more natural to first assort the earths to be operated upon, even if all were wished to go through different processes. good thing is worth doing, is it aot worth while to do it well from the firet?” ‘Then why not turn every useful item to some advantage, purticularly where nature supplies the raw material as cheap as dirt. Of every country possessing miacral territory, as of every person in the possession of miaeral property, the duty is clearly defiaed. The hoad to the letter imposes on the community and on the individual so endowed the industry to explore and work. There is no evading the responsibility ; whatever the surface cultivatioa, room must be accorded to the miner tor his operations, otherwise the value’ of property in its fulness and reality cannot he reached ; it will remain inert art consequently suffer in their most important interest. It caanot he admitted that Lord Bacon was even wise in his geaeration, when he hade the world aot to “ moil” for richee underground ; experience, at the present time, explodes sueh pbilosophy, and with eye of statd speculation and unwavering hand poiuts to the fact, that the balance of labor betweea agriculture and mechanics could not he prosperously sustained in this, or ia any other country, where mine works were to be discourage or neglected, and impressively directs the energies of every people to such, as constituting an indnstrial umines will pay for working ia the ordiaary way. . There is aa old maxim that saye, “ If aay . . and useless to a serioas extent, aad science aad, ultimately on to fortune., Short-sighted, traly, is the poliey which would restrain a seetion of people, even in anew settlement, from this nvailable means of advaneement. ‘The toil of the husbandmnn nnd the tending of the feeder ol the flocks nnd herds, are not the only inapirations of intelligenee to which people in a new country should hold themselves aceessible. Wine und cattle, vegetables nnd eereals, are, uo doubt, profitable, aud dot the landseape attraetively, but the nomad and the culturer would ill serve the world nt ite aetual eivilized age, were there no * dark and dangerous ie and traps of mines and mining,” with the ong, smoking ehimneye nnd the ponderous ny = chinery to whieh they ininister in their nutural imposing positions over the face of the land. After providing for the wante of animul life, the inineral resources of n settlement nierit the earliest testing ; nnd this attended to, tiine will be faken hy the forelock to the promoting of thnt eomimeree and manufacture whereby the purposes of eivilization ure hest served and ite priueiples universally utilized. So sel!-evident a requirement in the sphere of human induatry needs no lengthened discussion to prove its worth, and reeommiend it as materially important. The “knights of the pick” are not mere Quixotes. "They have their uses, and those usee are, at the present day, more than ever great and acknowledged faets. Ina word, those ertuut explorers are the first rank servitors of the commonwealth. They are those who open the little rivulets whose nuited waters make up the great streum of gold and silver, whoee constant flow is an absolute aecessity. to the successful prosecution of those great sehemes of ninnoulaeture and ecommerce, whieh, during the pust decade anda half, has so immensely advanced the mnterial progress of the eivilized world. Witbout their aid the smoke of our foundries and furaaces would no more be seea; the iroa horse aad his track would be dormant and dead in the bosom of mother earth ; the thanders of our war fleeta would be hushed ia silence, and our merchant marine would dwindle away to pigmy proportions. In concluding, for the present, this eeries of articles upon n subject so absolutely inexhaustive, aust rely upon the indulgeace of the readers of these papers forany imperfectinne or omissions which may have beea aotieed. My aim has been fulfilled if I have succeeded in pointing out certaia renctione which may be euggestive of further progress; or if I have beea beneficial in any way ia attracting attentioa tn the necessity and importaace of a more thorough and scientific treatment of the oree of the precioas metals, ia mining, upon the Pacific Coast. MINERS’ MASS MEETING AT SUMMIT CITY, EXCELSIOR DISTRICT. On the 8th instant, a lnrge and enthusiastic meetiag of the minere and citizeas coavened at Summit City, pursuaat. to a previous adjourament. J. A. Brumsey, Chairman. : Mr. Brumsey briefly stated the objecte of the meetiag to be to elect delegates to the Miners’ State Coaveatioa, to be held at Sacramento during tho winter of 1865-6. Mr. B. was followed by Mr. Thoe. Haanah, who spoke of the preat aecessity of a general Minere Convention oa this coast, and showed the benefits and advaatagee that would, doubtless, be derived from such aa orgaaization, and urged upon the gentlemen present the propriety of immediately taking eteps to show that they fully endorsed the call for eaid Conveation. The following resolutioas were adopted : Resolved, That we endorse the call of the Mining ana Scipntiric Press for a Miners’ Stnte. Convention, to be held at Sacramento, January 17th, 1865. Resolved, That a delegatioa of five menibers be chosen to represent, this mining district at said Convention, to he chosen as followe: Three delegates from Summit City, oae from Enterprise, and oae from old Mau Mountain and Baltimore. esolved, That ao general law can be made to fully meet the wants of the various mining districts ia this State. But we recommend the adoption of such general laws as may be applicable to the various mining districts in the State, reserving to the districts theniselves the right to make sueh ndditional regulatioae as may.be aecessary ia each individual case. Resolved, That the delegates elected from this district ehall attend the Miners’ State Coaventich, whenever said Conventson shall meet, whether under the late eall of the Mining ana Screntiric Press, or any euhsequent call that may be made. © The following-named gentlemea were elected as delegates : J. A. Brumsey, Thos. Hanaah, J. R. Stewart, delegates from Summit City. ; J. H. Fitzgerald, delegate {rom Eaterprise. F. W. Mitchell, delegate from Old Man Mountain and Baltimore. ; The meeting then adjouraed, subject to the pursuit which, if perseveringly followed, leads '.call of the Chairmaa.