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tious and experienced metallurgists. of California, at quicksilver, communicates to it a greatly en.
one time connected with the Geological Commission hanced power of adhering to metals, and par.
of that State, informed me that by his own determina- ticularly to those which, like gold and silver,
tions the saving in a large number of cases was barely lie toward the negative end of the electro-
30 per cent. of the gross contents of the ore, as shown
by careful assays, both of the ore and the waste. chemical scale. This power of adhesion, in the

The causes of this large loss are various, among case of these two metals, is so great, that the
which may be mentioned imperfect processes, in resistance, which I have found their surfaces,
sufficient 'comminution of the ore, and the diffi-

when in the native state, usually oppose to culty of bringing the gold into contact with the mercury. In an ore containing one ounce of gold to amalgamation (a resistance which is much the too of quartz or waste, the ratio is as one to greater and more general than has hitherto thirty-two thousand (1 to 32,000), or less than one- been recognized, and which is due to causes as fourth of one grain in one pound of stuff. It is , however, well known to all who are conversant instantly overcome, whether their particles be

yet undiscovered, or at least uninvestigated), is with gold amalgamation, that the mercury pears perfectly indifferent to the gold even when coarse, fine, or even impalpable. Even an arbrought in contact with it, failing to amalgamate it. tificial coating of oil or grease (which is such This indifference may be sometimes traced to a min

an enemy to amalgamation that the smoke of ute portion of grease, which effectually checks amal. gamation, but it is quite as often due to some other and the miner's lamp is pronounced highly detriless obvious cause, baffling often the skill of the best nental in gold and silver mines) forms amalgamators, and resulting in a ruinous loss of the obstacle to immediate amalgamation by this precious metal.

magnetic quicksilver. The atoms of the merNumerous inventions have been devised to save this loss, and avoid the causes which involve it, but condition by a minute particle of one of those

cury are, as it would seem, put into a polarie until lately with very indifferent success. most promising, viz., the use of mercurial vapor, has metals which range themselves toward the proved itself on trial in the large way a'failure, electro-positive end of the scale; so that its and the problem has remained, in a great measure, affinity for the more electro-negative metals is unsolved. Early in 1864 Prof. Henry Wurtz communicated

so greatly exalted that it seizes upon, and is to me in conversation his conviction, as the result of absorbed by their surfaces instantaneously. preliminary experiments, that the use of a minute The practical results obtained by using soportion of the metal sodium would impart to mercury dium amalgam, are highly satisfactory and surthe power of amalgamating with gold readily under pass any other method. Although comparany of the adverse conditions which had thus far atively wow, this process is now introduced into prored a serious drawback to the practice of this art. Leaving soon afterward for California, I have had no almost every gold district, according to the reopportunity, until within a few months past, of ac- ports in many scientific or mining journals. quainting myself with Mr. Wurtz's plans.

The amalgamation of auriferous iron pyrites, Prof. Silliman also explained some experi- such as are found especially in Colorado and ments made to illustrate the remarkable prop- Montana, is much more difficult and requires a erties imparted to mercury by sodium, and dis- very careful preparation of the ore, previous to covered by Prof. Wurtz. He says:

its contact with mercury. The first question to 1. Shake up in a test-tube a small quantity of mer

consider, is the state in which the gold occurs cury (say balf an ounce) with a moderately strong in the pyrites—whether as metal or as a sulsolution of sulphate of iron. The mercfiry' is pres. phuret. Most writers on the subject accept ently reduced to the condition of a thick mud, being the first, and if this be correct, the gold must so completely granulated (floured) as to resist all ef- be in exceedingly fine particles, which have to forts to restore it to its proper condition, and retain: be disclosed and freed, before mercury can act ing this condition almost indefinitely. Drop now a minute particle of sodium amalgam into it, when in- upon them. The ore, therefore, must be very stantly ihe whole is restored to its fluid state, and finely pulverized, and to do this, several new subsequent efforts to reproduce the granulas condi- machines were invented and tried with more tion are futile if the least trace of sodium remains.

or less success. But, notwithstanding this 2. Bring a particle of placer gold or gold from quartz into contact with a little clean mercury in its theory, the amalgamation of raw pyrites, howordinary condition. It will be seen to push the gold ever tinely powdered, is so incomplete, that in before it as it rolls about, and refuse to amalgamate many cases not over 20 per cent. of the metal with the gold, even when bencath its surface. In

is obtained. It was found, that the ore needed fact, there appears to be a sort of active repulsion be

to be desulphurized previous to its amalgamatween the two metals.

3. Bring the same particle of gold in contact with tion, to gain a reasonable percentage of the mercury having a minute portion of the sodium amalprecious metal. This process has been and gam dissolved in it, when immediately the gold is still is of immense importance for Colorado, completely enfilmed by the mercury and disappears where fuel is rather scarce, and the attention under its surface.

of metallurgists has been especially directed to The description of the discovery, as given by find a method which requires little fuel. One the inventor, shows, that it consists in impart- much in practise, is the apparatus of Keith, in ing to quicksilver greatly enhanced adhesion, which the ore is blown as a fine dust through attraction, or affinity for other metals and for a tubular vessel, being heated by the flame of its own substance, by adding to it a minute some fuel, brought in contact with the ore. It is quantity of one of the highly electro-positive reported, that this method has given excellent metals, such as sodium, potassium, ctc. A results. Compared with the amalgamation of minuté quantity of these metals, dissolved in the rai ore, it undoubtedly has, but it is not

easy to be seen how a complete roasting can be in motion, rocking forward and backward, effected by it. Probably the most successful while steam is introduced by means of a tube, apparatus or furnace for roasting, will be the and in about eight minutes the water boils, and so-called Terrace furnace, substantially a rectan- the mercury permeates the entire mass. After gular pris room, with a large number of so working for forty-five minutes, a stream of shelves of fire-clay arranged in such a manner cold water is let in, which suddenly cools the that the ore will fall from one to the two mass and precipitates the mercury. The gate anderneath and so on, until it reaches the at the end of the cylinder is then opened and a lower part of the furnace, from whence it is stream of water run through the cylinder, nnremored. The furnace is heated first by a til it comes clear, when the gate is closed and a temporary hearth, but the combustion of the new charge is put in. The shaking-tables are sulphur produces afterwards enough heat to merely to collect small particles of inetal, which keep the ore constantly in a temperature fit to may have been thrown from the cylinder by expel the sulphur from the same. Another the force of the water. Mr. Wykoff claims method has been proposed, and we believe to be very successful with his method, and with much success. It is the invention of Mr. to save in this way nearly all the gold conMonnier, and consists in calcining the ore in tained in the ore. reverberatory furnaces with an addition of sul- The amalgamation of silver ores is much phate of soda. The whole is calcined at a low more complicated, and requires more skill and temperature, and during the operation the sul- experience for a successful and economical phurets of iron and copper are at first oxidized, treatment than the gold ores. In order to exbut partly changed into sulphates during the plain the theory of this process, it is deemed last hours of the calcination. These sulphates necessary to remark, first, that the silver ores can be leached ont, and, so far as the copper is which are subjected to this treatment are genconcerned, it can be won by a precipitation erally sulphurets, arseniates, and antimoniates with metallic iron. The remaining ore, after of silver, or compounds of these bodies. The the lixiviation of all soluble salts, is chiefly com- older theory was, and is yet accepted by many posed of peroxide of iron and the gangue or authorities, that these sulphurets, when brought quartzose substances which were in the ore; together with common salt (chloride of sodium) the whole containing the gold well disclosed and and sulphate of copper, under proper condiready for the attack of the quicksilver. An ad- tions, are changed into chloride of silver, and vantage in this process is the small quantity of that the subsequent contact with mercury would fuel needed, and more especially the soft state decompose these chlorides into metallic silver, of every particle of peroxide of iron, which which forms an alloy with the quicksilver, allows an easy access of the mercury to the while another part of the latter takes up the most minute parts.

second atoms of chlorine, and forms protoIn many mines the vein-matrix is composed chloride of mercury, or calomel

, which is lost. of quartz, which has both free metallic gold, Another theory is that of Mr. Bowring, who and anriferous pyrites. In such cases the ore endeavors to prove that the dento-chloride of is often treated with mercury in the raw state, copper, produced by chemical action from comor it is at least passed over copper plates, which mon salt and sulphate of copper, is changed, in are alloyed or amalgamated, and retain all the contact with mercury, into a proto-chloride, free particles of gold, after which the ore is and the latter, under the influence of atmoscalcined and amalgamated.

pheric air, to oxi-chloride of copper, which, in Should the ore have too inuch copper pyrifes its turn, gives a part of its oxigen to the suland zinc-blende or galena mixed with the quartz phurets of silver, prolucing metallic silver, and iron pyrites, it becomes often too diflicult and leaving again proto-chloride of copper and and expensive to apply amalgamation, and the sulphuric acid as products of decomposition. treatment by smelting is preferable.

It will thus be seen how many chemical actions The great improvements in desulphurizing come into play in these processes, and how impirites, by which so great quantities of gold are perfectly they are understood yet. It may be saved, have given an impulse to an active and said that during the last few years many protitable mining system in several of the Terri- experiments were made to improve the amalgatories, especially in Colorado.

mation of silver ores, especially in Nevada, A peculiar method of amalgamation for gold where, amongst a great deal of quackery and ores has lately been put in practice by a Mr. absurdity, several inventions of some merit Vykotf, which he calls the “chloride of sodi- were introduced. am" process. The machinery used consists of Under nearly all circumstances it is necessary a wooden cylinder, combined with a shaking- to roast the ore, previous to its further treattable, with the ordinary mechanical appliances ment, with an addition of salt (chloride of for working them. The process itself is as fol- sodium). An exception to this rule forms the lows: Two hundred pounds of finely-crushed method introduced by a Mr. Smith, who amalore is put into the cylinder or amalgamator, gamates with but few chemical agents, except with about one hundred pounds of mercury common salt, the sulphurets of silver, found in 301 sixty gallons of water, to which three per the Comstock Lode, and some other mines, ceat. of sult is added. The cylinder is then set The apparatus ho usos is known under the name

VOL. VI-2

A

of Whecler's or Hepburn's pan, and it appears as too much fluidity will cause the settling of the that it is principally the friction between the sand and prevent a uniform division of the iron parts of the apparatus and the ore which, mercury, while, on the contrary, the particles in this process, causes a decomposition of the of ore cannot change their places quick enough, silver ore, and its fitness to form an alloy with and prolong, therefore, the operation. The thie mercury. It ought to be remarked, how- pan being filled in this manner, the quicksilver ever, that the presence of much antimony or is added in quantities of thirty to eighty pounds, arsenic in the ore is greatly objectionable, and and, if salt is to be used, it nay be done so that in such cases the ore has to be previously immediately, while all other chemnicals are only calcined. With ordinary care, the percentage applied a little afterward. The temperature is of silver extracted from the ore varies between kept, as near as possible, uniform, and near the 70 and 80 per cent., compared with the yield boiling-point of water. The number of revoof the assay, and it cannot be overlooked that lutions of the agitator is from ten to fifteen this system is of great importance in a country per minute, but they can be increased without whero fuel is so scarce as in Nevada.

inconvenience. The operation is finished in The chemicals which are more or less used about three or four hours; at that time the in the mills in Nevada are numerous; they are mass is diluted with water, and after half an employed, with the exception of the common hour tapped carefully in an adjoining vat, where salt, in a state of solution. We give a list of such traces of amalgam are separated as might the more important ones :

have gone with the fluid mass. The great 1. Sulphate of copper (bluestone). Out of a quantity of amalgam now on the bottom of the solution of this salt metallic copper is precipi- pan remains, and acts on a new portion of ore tated, when in contact with iron. The freed until it has become sufficiently solid, when it copper forms an alloy with the quicksilver is removed and pressed through a filter of amalgam, which is again decomposed by sul- leather or strong linen cloth. As already rephide of silver, through electro-chemical action, marked, the pans known as “Wheeier's and producing silver amalgam, and probably sul- “Hepburn's " seem to give the most favorable pbide of copper.

results, in consequence of their peculiar con2. Sulphate of iron (copperas).

struction. It is believed that they give a better 3. Bisulphate of soda. This salt gives up one percentage than other pans, and some estimate atom of its acid, and is reduced to a neutral salt. the difference as much as ten per cent. The 4. Alum.

actual loss of mercury has not yet been accu5. Sulphuric acid. The acid is used in a rately ascertained, or if so, has not been made diluted state, and appears to act directly on public. sulphides of silver, which may be seen by the A Hepburn pan of ordinary size can treat development of sulphuretted hydrogen gas, about four tons of ore in twenty-four hours, immediately after the application of the acid. and requires two and a half horse-power.

6. Chloride of sodium (common salt). It The amalgain, after being pressed, is distilled does not act directly on the sulphides of silver, in retorts, generally 19ade of cast iron, four but must be first decomposed by some agency feet long, eleven inches wide, and nine inches before its chlorine can act on the ore.

high. The same is connected with a condens7. Proto and deuto-chloride of copper. These ing apparatus, which is kept cool by water, salts act similar to the sulphate of copper. and in which the vapors of mercury are con

These and many other substances are used densed and liquefied. with or without success in the Nevada mills. It may be interesting to finish our remarks An untold number of experiments have been about amalgamation, with a description of this made, many patents issued for so-called new

process as applied to so-called speiss and blackprocesses, while some "inventors” kept their copper, the first being a product from treating method strictly secret; but to the present day arscnical and antimonial ores, also containing no treatment has been discovered for amal- silver, nickel, and copper--the other (blackgamating such complicated silver ores, which copper), an impure metal from mixed copper would give all the silver contained therein, and ores containing 80% copper, and remainder iron, more especially under such difficult circum- sulphur, lead, and antimony, besides some silstances as prevail in Nevada.

These classes of ores and products are not It leads us too far, considering the space for yet known well in this country, but there can this article, to describe the different systems of be no doubt that the amalgamation or humid amalgamators, and it could hardly be done extraction of the precious metals from these without figures. But it may be interesting to substances, will have to be resorted to, with the give a short description of the modus operandi increased development of the mineral resources. followed in the process of amalgamation. In The following methods are practised in the some pans, chemicals and raw ore are used; in Stephanshütte, in Hungary. Black-copper, afother cases, the ore is first roasted, and often ter being granulated and ground fine by stampno chemicals are resorted to. In the first case, ers and arrastras, is mixed with 10% conmon some water is first put in the pan and tinely- salt, and calcined in a double calcining furnace, pulverized ore, enough to give a certain consist with a low, slowly increasing heat during ten ency to the mass, which is of much importance, hours. The silver is thus converted into 9

ver.

chloride, and the sulphuric and antimonial salts The war of Spain against the republics of decomposed to a great extent.

Chili and Pern continued throughout the year. The amalgamation is performed in barrels, The Spanish fleet bombarded the port of Valwhere the powdered copper is mixed with a paraiso, inflicting considerable damage, and quantity of saline water, some more salt, and subsequently the port of Callao, where they for every 1500 lbs. substance about 100 copper were repulsed. Their strength then seems to balls. If much free acid is in the mass, quick- to have been spent, for they refrained from lime is added for neutralization. After some committing any further hostilities. The allirevolutions, quicksilver is added, and then the ance between Chili and Peru was joined by casks revolved for eighteen hours, after which the republics of Bolivia and Ecuador, while the the usual way is to wash the amalgam and treat United States of Colombia, and other states of it further. The amalgamation of the “speiss” South and Central America, declined it. The is performed in nearly the same manner, with allied republics expelled all the Spanish resiadditions of crude lime to the charge.

dents from their territories. (See Bolivia, Cmli, AMERICA. The great task which, during ECUADOR, Peru, SPAIN.) the year 1866, occupied the attention of the On the Atlantic side of South America, ParaGovernment and people of the United States, guay bravely defended herself against the united was the work of reconstruction. It soon be- forces of Brazil, the Argentine Republic, and came apparent that the views of the President Uruguay. Toward the close of the year the and the majority of Congress on the subject armies of the Argentine Republic and Uruguay widely differed. The latter embodied its views were withdrawn, and it was believed that the in the Civil Rights and Freedmen's Bureau alliance was at an end. The Presidents of both Bills and in a new Constitutional Amendment. the allied republics were threatened with dangers The President expressed his disagreement with at home, and Paraguay was expecting aid from the amendment, and vetoed the two bills, both Bolivia. (See ARGENTINE REPUBLIC, Bolivia, of which were, however, passed over his veto Brazil, Paraguay, Uruguay.) by Congress, and declared to be laws. The The successful laying of the Atlantic cable Thirty-ninth Congress, during its first session, brought North America into telegraphic comadmitted Tennessee, after its Legislature had munication with the Old World. This comratified the Constitutional Amendment. The munication remained free from interruption elections, held during the year, resulted in throughout the year. The rapid progress of every Northern State, and in West Virginia the Russo-American telegraph will soon give and Missouri, in favor of the Republican party, new guaranties for the permanency of this comwhile in Maryland and Kentucky the conserva- munication. tive opposition was triumphant. The late se- The total population of America exceeds at cession States, with the exception of Tennessee, present 80,000,000, of whom about 48,000,000 were unanimous in rejecting the Constitutional belong to North America and Mexico, 2,500,Amendment. (See UNITED STATES.)

000 to Central America, 3,970,000 to the West British America was greatly excited by inva- Indies, and 26,000,000 to South America. sions of the Fenians, which, however, were, ANGLICAN CHURCHES. The general without great difficulty, suppressed. In order statistics of the Protestant Episcopal Church to carry through the Confederation scheme, in the United States in 1866 were, accorddelegates from all the provinces went to Eng- ing to the “Church Almanac" for '1867, as land to confer with the Home Government, and follows: it was understood that a bill concerning the Dioceses

34 projected Confederation would be laid before Bishops.. the Imperial Parliament early in 1867. (See Priests and Deacons.

2,486 BRITISH AMERICA.)

Whole number of Clergy.

2,580 Parishes

2,305 France, for purposes of her own, resolved to Ordinations-Deacons withdraw from Mexico the French forces in

Priests,

86 three detachments, the first to take place in Candidates for Orders.. November, 1866, and the last in November,

Churches consecrated. 1867. The failure of the French Government

Baptisms-Infants..

23,974 Adults,

6,527 to withdraw the first detachment at the time

Not stated.. caused it to make then the necessary prepara- Confirmations

19,296 tions for recalling all the troops by March, Communicants-Added

14,138

Present number. 1867. In consequence of this new turn of the

161,224 Marriages

9,900 war, the Liberals made rapid progress in the Burials..

16,828 repossession of the country. Maximilian, at Sunday-School Teachers.

17,570 first, intended to abdicate, but subsequently

Scholars.

157,813 resolved to fight for his crown at the head of

Contributions

$3,051,669.64 the Conservatives and Church party. A neiv The following table exhibits the number of split arose, however, among the Liberals. Gen. clergymen, parishes, communicants, teachers Ortega disputing the claira of Juarez to the and scholars of Sunday-schools, and the amount presidency after the expiration of his legal term. of missionary and charitable contributions for (See Mexico.)

each diocese :

44

98

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226 38

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66

808

66

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81 30 154 20

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$10,186 82 175,854 69 23,906 95

10,105
2,553

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Alabama..
California..
Connecticut.
Delaware
Florida
Georgia.
Illinois...
Indiana..
Iowa..
Kansas
Kentucky.
Louisiana.
Maine....
Maryland...
Massachusetts.
Michigan
Minnesota.
Mississippi.
Missouri
New Hampshire.
New Jersey.
New York...
North Carolina.
Ohio....
*Pennsylvania.
Pittsburg
Rhode Island.
South Carolina..
Tennessee..
Texas...
Vermont.
Virginia
Western New York.
Wisconsin

44 33 131 26 14 27 82 36 46 15 84 48 19 136 76 68 27 44 34 22 101 328 49 97 162 41 35 68 24 29 37

45,054 03 39,123 03

5,477 29 112,534 34 185,461 29 85,271 60 87,860 42

660 199

4,723
1,736

196

37 12 31 37 17 157 120 64 36 27 32 24 118 406

51 100 218 33 35 72 27 20 30 117 164 69

138

2,420

91 844 1,677

240 239

44 207 102

4 690 1,560

421

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49,562 03

6,415 96 229,135 13 811,231 33

13,733 60 181,993 59 327,357 93 85,472 23 40,460 62

9,691 35 23,983 26 44,823 01 11,229 60 80,199 59 303,226 19 69,678 58

172

155
45

The movement for a reunion of the South- bishop of the House of Bishops, the promise of ern dioceses with the General Convention of conformity comprised in the office for the conthe Protestant Episcopal Church of the United secration of bishops; and, secondly, that he States, which began at the close of the year should also transmit to the said presiding bishop 1865, made rapid progress after the beginning the letters of his consecration, or, in default of of the year 1866. The diocesan convention of the existence of such letters, other sufficient Alabama voted in favor of reunion in January, evidence as to the fact of his consecration, and those of South Carolina and Florida in Feb- the bishops by whom it was done, and the ruary, and those of Virginia, Mississippi, and other persons by whom it was witnessed. The Louisiana in May, thus completing the resta- presiding bishop thereupon officially announced ration of the national unity of the Church. In that the necessary regulations having been fulmost of the diocesan conventions the vote was filled, "the acceptance and recognition of the unanimous in favor of reunion; a notable op- Right Rev. Richard Hooker Wilmer, D.D., as position being made only in that of Virginia, the Bishop of Alabama, is now complete.” in which fifty-four clerical and thirty-six lay The annual meeting of the Board of Missions delegates voted in the affirmative, and seren was held in October, in Providence. The reclergymen and eleren laymen in the negative. ceipts of the domestic committee for general The bishops of the dioceses notified the presi- purposes amounted to $54,645, and those of ding bishop of the Church in the United States the foreign committee to $71,000. The “ Amerof the fact, and the president bishop in his turn ican and Church Missionary Society" held its officially announced to the Church the consum- seventh anniversary at New York, in October. mation of the reunion. Bishop Wilmer, of The society employed during the past year 38 Alabama, who had been elected and consecrated missionaries, of whom 12 were new appointwhile the Southern dioceses formed a separate ments, and 24 recommissioned ; seven resigned. organization, complied on January 31st with The receipts were $56,412.38, and the expenthe conditions provided for his rocognition by ditures $54,227.62. The balance on hand Octothe triennial General Convention of 1865, ber 1, 1866, was $2,184.76. It was resolved at namely: first, that he should transmit in wri- the anniversary meeting that “committee ting (to be signed by him in the presence of of five be appointed to confer with the Evan. three bishops of the Church) to the presiding gelical Educational Committee, already existing.

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