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leaving in it a small piece of metallic gold undissolved. Accidentally, some extraneous substance, supposed to be a piece of cork, had fallen into the solution, decomposing it, and causing the gold to precipitate, which made a deposit in the metallic state, as in the electro-plating process, around the small piece of undissolved gold, increasing it in size to two or three times its original dimensions. Considering this accidental experiment of Mr. Daintree's as in some measure supporting Mr. Selwyn's theory, Mr. Wilkinson followed it up by a few simple experiments in the same direction, which he details in his paper. In his experiments a small chip of wood was generally used as the decomposing agent. In one instance he used a piece of leather. All through the wood and leather gold was disseminated in fine particles, and, when cut through, the characteristic metallic luster was highly reflected. From various experiments it would appear that organic matter is the necessary chemical agent for decomposing a solution of the chloride of gold in order to precipitate the gold as a coherent coating around a nucleus; and that, so far as Mr. Wilkinson had yet tried, iron, copper, and arsenical pyrites, galena, antimony, molybdenite, blende, wolfram, and metallic gold constitute essentially favorable nuclei to determine this chemical reaction. It is to be observed, too, that organic substances, such as fragments of wood, roots of trees, etc., ocour abundantly in the gold drifts of Australia. If water holding gold in solution circulates through the rocks and drifts, all the conditions necessary for the production. of gold dust and nuggets by deposit are present. Does the water so circulating now hold gold in solution?
One would think it would not be difficult for a chemist in Australia or California to determine the fact by direct experiment, but it does not appear that it has ever been tried. Mr. C. Wilkinson, however, quotes facts which lend probability to the view that when the trial is made the question will be solved in the affirmative. In testing a solid mass of iron pyrites Mr. Daintree found gold throughout. The mass retained the structure of a tree stem, in which the organic structure was replaced by pyrites. It had been taken from the Ballarat drift, and the same experiment was repeated by Mr. Newbury, the geological survey analyst, on another stem taken from the same drift, with a like result. Gold in such deposits assumes a mammillary form, which appears analogous to that presented by the surface of nuggets-a point of some importance, for, in the first place, it is a question whether a mammillary surface is the kind of surface that would be produced by abrasion and attrition; and, in the next place, abrasion or attrition can certainly have nothing to do with its appearance in these golden petrifactions. We cannot avoid attaching the greatest importance in relation to the question to the presence of gold in pyrites that has been formed in wood imbedded in auriferous drifts. The gold must have been in solution when so deposited, and everything will then depend on the age of the so petrified wood. If contemporaneous with the drift, the question is answered. Another fact to the same effect is, that sometimes gold incloses a nucleus of brown iron, etc. This is obviously quite inconsistent with such pieces of gold having been abraded, as they are out of crumbling rocks; such nucleated pieces of gold are never found in reefs. It is the old puzzle of a reel in a bottle. In relation to this we may remark that we believe that nuggets have never been found in the gold-fields of Brazil. We have the authority of Mr. Harding, a gentleman well known for his great practical knowledge of gold mines and mining in that country, that he never met with nor heard of a nugget, properly so called, in all his many years' experience in the gold district of Brazil; but, on the other hand, it is there almost invariably found in veins in connection with or in the vicinity of some other metal, generally iron. In what is probably the most prolific mine of gold that has ever been known in the whole world, that of San Juan del Rey, (the value of which was not long since so seriously depreciated by the accidental destruction by fire of the wooden ladders, supports, and machinery,) the gold is found in a matrix of porous iron or agglutinated iron sand, called Jacotinga, which consists of a bed or vein not a foot in width, but so incredibly rich that on one occasion, when our informant was on a visit to the manager, there was brought in on an assiette, as a sort of dessert for the eyes after dinner, a lump of gold ore that had been extracted that day from the mine. It was about the size of a large fowl; not so big as a turkey, but bigger than a duck. It was a mass of Jacotinga iron, with gold all mingled and streaked through it. The gold, when afterward extracted, was found to amount to 30 pounds weight. On the previous day the amount of gold obtained from the Jacotinga had been 67 pounds, and on the day following 130 pounds, equal in value to about £8,000. We only mention it as a corroborative instance of the concurrent presence of gold and iron. Lastly, as pointed out by Mr. Wilkinson, it must be admitted that the fact that gold may be greatly purified by dissolving and reprecipitating it, is very suggestive of the generally higher standard of alluvial over reef gold being due to a similar cause
THE BULLION PRODUCT.
The difficulty of ascertaining the production of gold and silver in this country is peculiarly great, by reason of the lack of organized means and the extent of the field through which our mines are scattered, as well as the nature of the industry itself, and the motives which influence the minds of those engaged in it to withhold from publication the full and true account of its results.
When I entered upon my duties as commissioner of mining statistics I gave this subject careful attention. My predecessor had presented estimates of bullion production, involving confessedly a large excess over the amount actually accounted for by the statistics of either express shipments, exports and coinage, or the bullion tax. He had recommended the collection of accurate and comprehensive returns through resident agents in the mining States and Territories-a system which was not practicable then, and has not been practicable since, on account of the limited funds appropriated for the work. So far, however, as circumstances would permit, I have pursued the policy of obtaining from. experts in different regions estimates of such portions of the production as were not covered by detailed and accurate returns, using, moreover, my own judgment, based upon extensive annual journeys of observation, in the modification of such estimates as I had reason to believe were without sufficient foundation. The elements entering into conclusions of this character are: the reports of production from single leading mines; the express shipments of bullion; the rates charged by express companies; the number of miners, white and Chinese, and the respective wages paid; the number and capacity of stamps running; the cost of mining and reduction, etc. The aggregate product of bullion thus obtained is of course merely a rude estimate. It has never been put forward as anything else, and I do not feel called upon to defend its accuracy.
As I committed the error of including my estimate of bullion in the introduction to my report of last year, which was set up and stereotyped several months before the last pages went to press, it does not agree with later estimates in the different chapters of the report. Thus Oregon and Washington are credited on page 7 with a product of $4,000,000; on page 205, their aggregate production is stated as $3,000,000. Again, Montana is credited on page 7 with $12,000,000; on page 317 this is corrected, and the cause of the error explained, while the product is cut down to $9,000,000, on the strength of later reports as to the effect of drought on the gulch mines.*
But all the excess of gold attributed in the introduction to my last report to Oregon, and more than a million of the excess in the earlier estimate for Montana, (made in September, and based on the product of the fiscal year, without foresight of the excessive drought,) belonged properly to California. For I have never been able to get direct returns from all the mining districts of that State. The attempts which have been made are detailed in a former report; and it is the experience of all who
*I declared (p. 317) that $9,000,000 seemed to me too small a figure. The surveyor general's official estimate for the year was $10,000,000. My investigations this year, however, corroborate the correspondent who sent me the smaller estimate.
have undertaken to obtain such information in California that the task is well-nigh an impossibility. The San Francisco press, noted for its enterprise in statistical matters, contents itself with presenting annually the receipts of the express companies, the coinage at the mint, and the shipment of bars, data which give, within a certain percentage, the amount of the precious metals received at San Francisco. I have usually deducted from this aggregate the amounts due to Arizona, Nevada, Oregon, Washington, Idaho, and Montana, (not the whole product of all these States and Territories, but the portion sent to San Francisco,) and credited California with the rest. That this gives a fairer result than could be obtained by a direct inquiry may be seen from the ill success of the assistant marshals under the Census Bureau, the aggregate of whose returns of gold product in California, submitted to me in January, 1871, was between $8,000,000 and $9,000,000 for the whole State, and for the whole of the year ending June 1, 1870.
Following the plan above mentioned, I obtained for California the sum of $20,000,000, which agreed with my own observations of the depressed condition of the placer mines in many districts, and of certain other causes operating to produce local diminution of product. But this estimate was too low, because the amounts subtracted for Oregon and Montana were too high. The table given in my introductory letter last year is therefore to be rejected, as contradicted by the later evidence of the body of the report. I regret that attention was not more distinctly called to this fact in the appendix; but the truth is, that I did not keep in mind, as the voluminous work passed through the press, the whole of those parts which had gone beyond my reach; and the corrections made upon later evidence, in the chapters on Oregon, Montana, etc., were introduced without proper regard to their bearing upon what had been said hundreds of pages before.
If the estimate of bullion product for 1869 had been the last instead of the first thing in the report, it would have been conformed to these corrections. I can now only introduce the corrected table as my estimate for 1869:
The term "all other sources," which I have retained from the reports of my predecessor, does not very definitely show the meaning intended. This item includes the product of precious metals east of the Rocky Mountains, and also a small margin of compensation for underestimates upon single States or Territories.
The following is my estimate of the product of 1870:
$25,000,000 9, 100, 000 6, 000, 000 1,300,000
66, 000, 000
All the above items, except the first and last, are based upon direct and positive evidence, collected, sifted, and weighed with my best care and judgment. The product of California is obtained, as usual, by a series of deductions from the receipts of bullion at San Francisco. have no better way, since it would be absurd to accept the results of direct inquiries in that State as covering the whole product. Such a course would put California down to about $9,000,000, which I should consider outrageously unjust. I believe that my estimate is nearly correct. These results are obtained without reference to the statistics of coinage and export, and largely exceed the aggregate of those two items. According to some writers, however, the total annual product of bullion may be closely approximated by merely adding together the coinage of domestic gold and silver at the mint and its branches, (or the deposits for coinage less the amount returned to depositors in bars,) and the exports of bullion of native production. I do not agree with this view, and I shall give at some length my reasons for dissent. These may be classed under two general heads: first, the imperfection of the data afforded for an accurate calculation of either coinage or exportation; and second, the inadequacy of the method itself. I need scarcely add, that if I had not become sincerely convinced on these points, I should certainly have saved myself much independent labor and research, and adopted the comparatively very cheap and easy system of studying the mining industry and its results by means of mint and custom-house reports.
I will first give some tables, constructed on the method referred to, and show their deficiencies.
The following figures for the domestic deposits of gold and silver for coinage are obtained by taking from table C (now B) the reports of the Director of the Mint, the deposits at the Philadelphia and San Francisco mints, and adding the amount of fine bars received at the Mint in Philadelphia, as shown in table A. It would be easy to show that this does not give an exact result, since no account is taken of the fine bars produced at Philadelphia, nor of the foreign origin of a portion of the fine bars deposited at San Francisco, or sent from New York to Philadelphia, nor of the native origin of a portion of the jewelers' bullion; but it is the best that can be done with the Mint reports as they are at present made out. The amount of silver bars produced at San Francisco is deducted from the reported deposits at that place, and for 1866 and 1870, the amount of fine silver bars sent to Philadelphia evidently including a large portion of foreign origin, I have taken instead the amount produced at New York, as involving less error.
The figures of the exports of bullion are compiled from the reports of the Bureau of Statistics of the Treasury Department:
Table of domestic coinage deposits and exports of domestic bullion for the fiscal years ending June 30, 1866, 1867, 1868, 1869, and 1870.
*Including deposits at Carson City, (less $66, fine bars produced there.) A deduction has been made of $1,274,458, Japanese gold, received as domestic at the San Francisco mint.
The sum of domestic deposits at Philadelphia, San Francisco, Carson City, and the fine bars from New York. The table on page 43 of the Director's report for 1870 erroneously omits Carson City. I am forced to assume that the $707,400, silver bars of the New York assay office, were sent to Philadelphi for coinage, as there is no means of separating the small amount returned to depositors.
The Alta California of February 17, 1871, makes the following observations:
The true mode of getting at the production has been pointed out, and, for the last six years, we have annually given the production of this coast as received at San Francisco. The method is the same as that adopted in regard to the cotton crop and other great staples. It is by ascertaining how much cotton is exported, how much burned and destroyed, and how much is taken by the manufacturers. The result is taken by the world at large as the cotton crop. It would not shake confidence in the figures if some statistical neophyte were to object that some cotton is used to stuff into people's ears when they have the earache, and is therefore not thus accounted for. So with gold and silver. The world knows that raw bullion is of no use to the producer; it must be turned into coin, or sold as bars. In either case the whole quantity.is practically accounted for-that is, all the gold and silver which affects the markets of the world comes to light in this manner. The production of the metals in the United States has been, for five years, as expressed in the following table, showing the net amount of domestic gold and silver deposited at mint and turned into coin, and the amount of bars of gold and silver exported by official return: