GENERAL TECHNICAL DATA.
For the purposes of efficient management, the information gathered under this head is of equal, if not superior, importance to that under "working costs." Such data fall generally under the following heads:—
Labor.—Returns of the shifts worked in the various departments for each day and for the month; worked out on a monthly basis of footage progress, tonnage produced or tons handled per man; also where possible the footage of holes drilled, worked out per man and per machine.
Supplies.—Daily returns of supplies used; the principal items worked out monthly in quantity per foot of progress, or per ton of ore produced.
Power.—Fuel, lubricant, etc., consumed in steam production, worked out into units of steam produced, and this production allocated to the various engines. Where electrical power is used, the consumption of the various motors is set out.
Surveys.—The need of accurate plans requires no discussion. Aside from these, the survey-office furnishes the returns of development footage, measurements under contracts, and the like.
Sampling and Assaying.—Mine sampling and assaying fall under two heads,—the determination of the value of standing ore, and of products from the mine. The sampling and assaying on a going mine call for the same care and method as in cases of valuation of the mine for purchase,—the details of which have been presented under "Mine Valuation,"—for through it, guidance must not only be had to the value of the mine and for reports to owners, but the detailed development and ore extraction depend on an absolute knowledge of where the values lie.
CHAPTER XVIII.
ADMINISTRATION (Concluded).
| ADMINISTRATIVE REPORTS. |
In addition to financial returns showing the monthly receipts, expenditures, and working costs, there must be in proper administration periodic reports from the officers of the mine to the owners or directors as to the physical progress of the enterprise. Such reports must embrace details of ore extraction, metal contents, treatment recoveries, construction of equipment, and the results of underground development. The value of mines is so much affected by the monthly or even daily result of exploration that reports of such work are needed very frequently,—weekly or even daily if critical work is in progress. These reports must show the width, length, and value of the ore disclosed.
The tangible result of development work is the tonnage and grade of ore opened up. How often this stock-taking should take place is much dependent upon the character of the ore. The result of exploration in irregular ore-bodies often does not, over short periods, show anything tangible in definite measurable tonnage, but at least annually the ore reserve can be estimated.
In mines owned by companies, the question arises almost daily as to how much of and how often the above information should be placed before stockholders (and therefore the public) by the directors. In a general way, any company whose shares are offered on the stock exchange is indirectly inviting the public to become partners in the business, and these partners are entitled to all the information which affects the value of their property and are entitled to it promptly. Moreover, mining is a business where competition is so obscure and so much a matter of indifference, that suppression of important facts in documents for public circulation has no justification. On the other hand, both the technical progress of the industry and its position in public esteem demand the fullest disclosure and greatest care in preparation of reports. Most stockholders' ignorance of mining technology and of details of their particular mine demands a great deal of care and discretion in the preparation of these public reports that they may not be misled. Development results may mean little or much, depending upon the location of the work done in relation to the ore-bodies, etc., and this should be clearly set forth.
The best opportunity of clear, well-balanced statements lies in the preparation of the annual report and accounts. Such reports are of three parts:—
| 1. | The "profit and loss" account, or the "revenue account." |
| 2. | The balance sheet; that is, the assets and liabilities statement. |
| 3. | The reports of the directors, manager, and consulting engineer. |
The first two items are largely matters of bookkeeping. They or the report should show the working costs per ton for the year. What must be here included in costs is easier of determination than in the detailed monthly cost sheets of the administration; for at the annual review, it is not difficult to assess the amount chargeable to development. Equipment expenditure, however, presents an annual difficulty, for, as said, the distribution of this item is a factor of the life of the mine, and that is unknown. If such a plant has been paid for out of the earnings, there is no object in carrying it on the company's books as an asset, and most well-conducted companies write it off at once. On the other hand, where the plant is paid for out of capital provided for the purpose, even to write off depreciation means that a corresponding sum of cash must be held in the company's treasury in order to balance the accounts,—in other words, depreciation in such an instance becomes a return of capital. The question then is one of policy in the company's finance, and in neither case is it a matter which can be brought into working costs and leave them any value for comparative purposes. Indeed, the true cost of working the ore from any mine can only be told when the mine is exhausted; then the dividends can be subtracted from the capital sunk and metal sold, and the difference divided over the total tonnage produced.
The third section of the report affords wide scope for the best efforts of the administration. This portion of the report falls into three divisions: (a) the construction and equipment work of the year, (b) the ore extraction and treatment, and (c) the results of development work.
The first requires a statement of the plant constructed, its object and accomplishment; the second a disclosure of tonnage produced, values, metallurgical and mechanical efficiency. The third is of the utmost importance to the stockholder, and is the one most often disregarded and obscured. Upon this hinges the value of the property. There is no reason why, with plans and simplicity of terms, such reports cannot be presented in a manner from which the novice can judge of the intrinsic position of the property. A statement of the tonnage of ore-reserves and their value, or of the number of years' supply of the current output, together with details of ore disclosed in development work, and the working costs, give the ground data upon which any stockholder who takes interest in his investment may judge for himself. Failure to provide such data will some day be understood by the investing public as a prima facie index of either incapacity or villainy. By the insistence of the many engineers in administration of mines upon the publication of such data, and by the insistence of other engineers upon such data for their clients before investment, and by the exposure of the delinquents in the press, a more practicable "protection of investors" can be reached than by years of academic discussion.
CHAPTER XIX.
The Amount of Risk in Mining Investments.
| RISK IN VALUATION OF MINES; IN MINES AS COMPARED WITH OTHER COMMERCIAL ENTERPRISES. |
From the constant reiteration of the risks and difficulties involved in every step of mining enterprise from the valuation of the mine to its administration as a going concern, the impression may be gained that the whole business is one great gamble; in other words, that the point whereat certainties stop and conjecture steps in is so vital as to render the whole highly speculative.
Far from denying that mining is, in comparison with better-class government bonds, a speculative type of investment, it is desirable to avow and emphasize the fact. But it is none the less well to inquire what degree of hazard enters in and how it compares with that in other forms of industrial enterprise.
Mining business, from an investment view, is of two sorts,—prospecting ventures and developed mines; that is, mines where little or no ore is exposed, and mines where a definite quantity of ore is measurable or can be reasonably anticipated. The great hazards and likewise the Aladdin caves of mining are mainly confined to the first class. Although all mines must pass through the prospecting stage, the great industry of metal production is based on developed mines, and it is these which should come into the purview of the non-professional investor. The first class should be reserved invariably for speculators, and a speculator may be defined as one who hazards all to gain much. It is with mining as an investment, however, that this discussion is concerned.
Risk in Valuation of Mines.—Assuming a competent collection of data and efficient management of the property, the risks in valuing are from step to step:—
| 1. | The risk of continuity in metal contents beyond sample faces. |
| 2. | The risk of continuity in volume through the blocks estimated. |
| 3. | The risk of successful metallurgical treatment. |
| 4. | The risk of metal prices, in all but gold. |
| 5. | The risk of properly estimating costs. |
| 6. | The risk of extension of the ore beyond exposures. |
| 7. | The risk of management. |
As to the continuity of values and volumes through the estimated area, the experience of hundreds of engineers in hundreds of mines has shown that when the estimates are based on properly secured data for "proved ore," here at least there is absolutely no hazard. Metallurgical treatment, if determined by past experience on the ore itself, carries no chance; and where determined by experiment, the risk is eliminated if the work be sufficiently exhaustive. The risk of metal price is simply a question of how conservative a figure is used in estimating. It can be eliminated if a price low enough be taken. Risk of extension in depth or beyond exposures cannot be avoided. It can be reduced in proportion to the distance assumed. Obviously, if no extension is counted, there is nothing chanced. The risk of proper appreciation of costs is negligible where experience in the district exists. Otherwise, it can be eliminated if a sufficiently large allowance is taken. The risk of failure to secure good management can be eliminated if proved men are chosen.
There is, therefore, a basic value to every mine. The "proved" ore taken on known metallurgical grounds, under known conditions of costs on minimum prices of metals, has a value as certain as that of money in one's own vault. This is the value previously referred to as the "A" value. If the price (and interest on it pending recovery) falls within this amount, there is no question that the mine is worth the price. What the risk is in mining is simply what amount the price of the investment demands shall be won from extension of the deposit beyond known exposures, or what higher price of metal must be realized than that calculated in the "A" value. The demands on this X, Y portion of the mine can be converted into tons of ore, life of production, or higher prices, and these can be weighed with the geological weights and the industrial outlook.
Mines compared to Other Commercial Enterprises.—The profits from a mining venture over and above the bed-rock value A, that is, the return to be derived from more extensive ore-recovery and a higher price of metal, may be compared to the value included in other forms of commercial enterprise for "good-will." Such forms of enterprise are valued on a basis of the amount which will replace the net assets plus (or minus) an amount for "good-will," that is, the earning capacity. This good-will is a speculation of varying risk depending on the character of the enterprise. For natural monopolies, like some railways and waterworks, the risk is less and for shoe factories more. Even natural monopolies are subject to the risks of antagonistic legislation and industrial storms. But, eliminating this class of enterprise, the speculative value of a good-will involves a greater risk than prospective value in mines, if properly measured; because the dangers of competition and industrial storms do not enter to such a degree, nor is the future so dependent upon the human genius of the founder or manager. Mining has reached such a stage of development as a science that management proceeds upon comparatively well-known lines. It is subject to known checks through the opportunity of comparisons by which efficiency can be determined in a manner more open for the investor to learn than in any other form of industry. While in mining an estimate of a certain minimum of extension in depth, as indicated by collateral factors, may occasionally fall short, it will, in nine cases out of ten, be exceeded. If investment in mines be spread over ten cases, similarly valued as to minimum of extension, the risk has been virtually eliminated. The industry, if reduced to the above basis for financial guidance, is a more profitable business and is one of less hazards than competitive forms of commercial enterprises.
In view of what has been said before, it may be unnecessary to refer again to the subject, but the constant reiteration by wiseacres that the weak point in mining investments lies in their short life and possible loss of capital, warrants a repetition that the A, B, C of proper investment in mines is to be assured, by the "A" value, of a return of the whole or major portion of the capital. The risk of interest and profit may be deferred to the X, Y value, and in such case it is on a plane with "good-will." It should be said at once to that class who want large returns on investment without investigation as to merits, or assurance as to the management of the business, that there is no field in this world for the employment of their money at over 4%.
Unfortunately for the reputation of the mining industry, and metal mines especially, the business is often not conducted or valued on lines which have been outlined in these chapters. There is often the desire to sell stocks beyond their value. There is always the possibility that extension in depth will reveal a glorious Eldorado. It occasionally does, and the report echoes round the world for years, together with tributes to the great judgment of the exploiters. The volume of sound allures undue numbers of the venturesome, untrained, and ill-advised public to the business, together with a mob of camp-followers whose objective is to exploit the ignorant by preying on their gambling instincts. Thus a considerable section of metal mining industry is in the hands of these classes, and a cloud of disrepute hangs ever in the horizon.
There has been a great educational campaign in progress during the past few years through the technical training of men for conduct of the industry, by the example of reputable companies in regularly publishing the essential facts upon which the value of their mines is based, and through understandable nontechnical discussion in and by some sections of the financial and general press. The real investor is being educated to distinguish between reputable concerns and the counters of gamesters. Moreover, yearly, men of technical knowledge are taking a stronger and more influential part in mining finance and in the direction of mining and exploration companies. The net result of these forces will be to put mining on a better plane.
CHAPTER XX.
The Character, Training, and Obligations of the Mining Engineering Profession.
In a discussion of some problems of metal mining from the point of view of the direction of mining operations it may not be amiss to discuss the character of the mining engineering profession in its bearings on training and practice, and its relations to the public.
The most dominant characteristic of the mining engineering profession is the vast preponderance of the commercial over the technical in the daily work of the engineer. For years a gradual evolution has been in progress altering the larger demands on this branch of the engineering profession from advisory to executive work. The mining engineer is no longer the technician who concocts reports and blue prints. It is demanded of him that he devise the finance, construct and manage the works which he advises. The demands of such executive work are largely commercial; although the commercial experience and executive ability thus become one pier in the foundation of training, the bridge no less requires two piers, and the second is based on technical knowledge. Far from being deprecated, these commercial phases cannot be too strongly emphasized. On the other hand, I am far from contending that our vocation is a business rather than a profession.
For many years after the dawn of modern engineering, the members of our profession were men who rose through the ranks of workmen, and as a result, we are to this day in the public mind a sort of superior artisan, for to many the engine-driver is equally an engineer with the designer of the engine, yet their real relation is but as the hand to the brain. At a later period the recruits entered by apprenticeship to those men who had established their intellectual superiority to their fellow-workers. These men were nearly always employed in an advisory way—subjective to the executive head.
During the last few decades, the advance of science and the complication of industry have demanded a wholly broader basis of scientific and general training for its leaders. Executive heads are demanded who have technical training. This has resulted in the establishment of special technical colleges, and compelled a place for engineering in the great universities. The high intelligence demanded by the vocation itself, and the revolution in training caused by the strengthening of its foundations in general education, has finally, beyond all question, raised the work of application of science to industry to the dignity of a profession on a par with the law, medicine, and science. It demands of its members equally high mental attainments,—and a more rigorous training and experience. Despite all this, industry is conducted for commercial purposes, and leaves no room for the haughty intellectual superiority assumed by some professions over business callings.
There is now demanded of the mining specialist a wide knowledge of certain branches of civil, mechanical, electrical, and chemical engineering, geology, economics, the humanities, and what not; and in addition to all this, engineering sense, executive ability, business experience, and financial insight. Engineering sense is that fine blend of honesty, ingenuity, and intuition which is a mental endowment apart from knowledge and experience. Its possession is the test of the real engineer. It distinguishes engineering as a profession from engineering as a trade. It is this sense that elevates the possessor to the profession which is, of all others, the most difficult and the most comprehensive. Financial insight can only come by experience in the commercial world. Likewise must come the experience in technical work which gives balance to theoretical training. Executive ability is that capacity to coördinate and command the best results from other men,—it is a natural endowment. which can be cultivated only in actual use.
The practice of mine engineering being so large a mixture of business, it follows that the whole of the training of this profession cannot be had in schools and universities. The commercial and executive side of the work cannot be taught; it must be absorbed by actual participation in the industry. Nor is it impossible to rise to great eminence in the profession without university training, as witness some of our greatest engineers. The university can do much; it can give a broad basis of knowledge and mental training, and can inculcate moral feeling, which entitles men to lead their fellows. It can teach the technical fundamentals of the multifold sciences which the engineer should know and must apply. But after the university must come a schooling in men and things equally thorough and more arduous.
In this predominating demand for commercial qualifications over the technical ones, the mining profession has differentiated to a great degree from its brother engineering branches. That this is true will be most apparent if we examine the course through which engineering projects march, and the demands of each stage on their road to completion.
The life of all engineering projects in a general way may be divided into five phases:[*]—
[Footnote *: These phases do not necessarily proceed step by step. For an expanding works especially, all of them may be in process at the same time, but if each item be considered to itself, this is the usual progress, or should be when properly engineered.]
| 1. | Determination of the value of the project. |
| 2. | Determination of the method of attack. |
| 3. | The detailed delineation of method, means, and tools. |
| 4. | The execution of the works. |
| 5. | The operation of the completed works. |
These various stages of the resolution of an engineering project require in each more or less of every quality of intellect, training, and character. At the different stages, certain of these qualities are in predominant demand: in the first stage, financial insight; in the second, "engineering sense"; in the third, training and experience; in the fourth and fifth, executive ability.
A certain amount of compass over the project during the whole five stages is required by all branches of the engineering profession,—harbor, canal, railway, waterworks, bridge, mechanical, electrical, etc.; but in none of them so completely and in such constant combination is this demanded as in mining.
The determination of the commercial value of projects is a greater section of the mining engineer's occupation than of the other engineering branches. Mines are operated only to earn immediate profits. No question of public utility enters, so that all mining projects have by this necessity to be from the first weighed from a profit point of view alone. The determination of this question is one which demands such an amount of technical knowledge and experience that those who are not experts cannot enter the field,—therefore the service of the engineer is always demanded in their satisfactory solution. Moreover, unlike most other engineering projects, mines have a faculty of changing owners several times during their career, so that every one has to survive a periodic revaluation. From the other branches of engineering, the electrical engineer is the most often called upon to weigh the probabilities of financial success of the enterprise, but usually his presence in this capacity is called upon only at the initial stage, for electrical enterprises seldom change hands. The mechanical and chemical branches are usually called upon for purely technical service on the demand of the operator, who decides the financial problems for himself, or upon works forming but units in undertakings where the opinion on the financial advisability is compassed by some other branch of the engineering profession. The other engineering branches, even less often, are called in for financial advice, and in those branches involving works of public utility the profit-and-loss phase scarcely enters at all.
Given that the project has been determined upon, and that the enterprise has entered upon the second stage, that of determination of method of attack, the immediate commercial result limits the mining engineer's every plan and design to a greater degree than it does the other engineering specialists. The question of capital and profit dogs his every footstep, for all mines are ephemeral; the life of any given mine is short. Metal mines have indeed the shortest lives of any. While some exceptional ones may produce through one generation, under the stress of modern methods a much larger proportion extend only over a decade or two. But of more pertinent force is the fact that as the certain life of a metal mine can be positively known in most cases but a short period beyond the actual time required to exhaust the ore in sight, not even a decade of life to the enterprise is available for the estimates of the mining engineer. Mining works are of no value when the mine is exhausted; the capital invested must be recovered in very short periods, and therefore all mining works must be of the most temporary character that will answer. The mining engineer cannot erect a works that will last as long as possible; it is to last as long as the mine only, and, in laying it out, forefront in his mind must be the question, Can its cost be redeemed in the period of use of which I am certain it will find employment? If not, will some cheaper device, which gives less efficiency, do? The harbor engineer, the railway engineer, the mechanical engineer, build as solidly as they can, for the demand for the work will exist till after their materials are worn out, however soundly they construct.
Our engineer cousins can, in a greater degree by study and investigation, marshal in advance the factors with which they have to deal. The mining engineer's works, on the other hand, depend at all times on many elements which, from the nature of things, must remain unknown. No mine is laid bare to study and resolve in advance. We have to deal with conditions buried in the earth. Especially in metal mines we cannot know, when our works are initiated, what the size, mineralization, or surroundings of the ore-bodies will be. We must plunge into them and learn,—and repent. Not only is the useful life of our mining works indeterminate, but the very character of them is uncertain in advance. All our works must be in a way doubly tentative, for they are subject to constant alterations as they proceed.
Not only does this apply to our initial plans, but to our daily amendment of them as we proceed into the unknown. Mining engineering is, therefore, never ended with the initial determination of a method. It is called upon daily to replan and reconceive, coincidentally with the daily progress of the constructions and operation. Weary with disappointment in his wisest conception, many a mining engineer looks jealously upon his happier engineering cousin, who, when he designs a bridge, can know its size, its strains, and its cost, and can wash his hands of it finally when the contractor steps in to its construction. And, above all, it is no concern of his whether it will pay. Did he start to build a bridge over a water, the width or depth or bottom of which he could not know in advance, and require to get its cost back in ten years, with a profit, his would be a task of similar harassments.
As said before, it is becoming more general every year to employ the mining engineer as the executive head in the operation of mining engineering projects, that is, in the fourth and fifth stages of the enterprise. He is becoming the foreman, manager, and president of the company, or as it may be contended by some, the executive head is coming to have technical qualifications. Either way, in no branch of enterprise founded on engineering is the operative head of necessity so much a technical director. Not only is this caused by the necessity of executive knowledge before valuations can be properly done, but the incorporation of the executive work with the technical has been brought about by several other forces. We have a type of works which, by reason of the new conditions and constant revisions which arise from pushing into the unknown coincidentally with operating, demands an intimate continuous daily employment of engineering sense and design through the whole history of the enterprise. These works are of themselves of a character which requires a constant vigilant eye on financial outcome. The advances in metallurgy, and the decreased cost of production by larger capacities, require yearly larger, more complicated, and more costly plants. Thus, larger and larger capitals are required, and enterprise is passing from the hands of the individual to the financially stronger corporation. This altered position as to the works and finance has made keener demands, both technically and in an administrative way, for the highly trained man. In the early stages of American mining, with the moderate demand on capital and the simpler forms of engineering involved, mining was largely a matter of individual enterprise and ownership. These owners were men to whom experience had brought some of the needful technical qualifications. They usually held the reins of business management in their own hands and employed the engineer subjectively, when they employed him at all. They were also, as a rule, distinguished by their contempt for university-trained engineers.
The gradually increasing employment of the engineer as combined executive and technical head, was largely of American development. Many English and European mines still maintain the two separate bureaus, the technical and the financial. Such organization is open to much objection from the point of view of the owner's interests, and still more from that of the engineer. In such an organization the latter is always subordinate to the financial control,—hence the least paid and least respected. When two bureaus exist, the technical lacks that balance of commercial purpose which it should have. The ambition of the theoretical engineer, divorced from commercial result, is complete technical nicety of works and low production costs without the regard for capital outlay which the commercial experience and temporary character of mining constructions demand. On the other hand, the purely financial bureau usually begrudges the capital outlay which sound engineering may warrant. The result is an administration that is not comparable to the single head with both qualifications and an even balance in both spheres. In America, we still have a relic of this form of administration in the consulting mining engineer, but barring his functions as a valuer of mines, he is disappearing in connection with the industry, in favor of the manager, or the president of the company, who has administrative control. The mining engineer's field of employment is therefore not only wider by this general inclusion of administrative work, but one of more responsibility. While he must conduct all five phases of engineering projects coincidentally, the other branches of the profession are more or less confined to one phase or another. They can draw sharper limitations of their engagements or specialization and confine themselves to more purely technical work. The civil engineer may construct railway or harbor works; the mechanical engineer may design and build engines; the naval architect may build ships; but given that he designed to do the work in the most effectual manner, it is no concern of his whether they subsequently earn dividends. He does not have to operate them, to find the income, to feed the mill, or sell the product. The profit and loss does not hound his footsteps after his construction is complete.
Although it is desirable to emphasize the commercial side of the practice of the mining engineer's profession, there are other sides of no less moment. There is the right of every red-blooded man to be assured that his work will be a daily satisfaction to himself; that it is a work which is contributing to the welfare and advance of his country; and that it will build for him a position of dignity and consequence among his fellows.
There are the moral and public obligations upon the profession. There are to-day the demands upon the engineers which are the demands upon their positions as leaders of a great industry. In an industry that lends itself so much to speculation and chicanery, there is the duty of every engineer to diminish the opportunity of the vulture so far as is possible. Where he can enter these lists has been suggested in the previous pages. Further than to the "investor" in mines, he has a duty to his brothers in the profession. In no profession does competition enter so obscurely, nor in no other are men of a profession thrown into such terms of intimacy in professional work. From these causes there has arisen a freedom of disclosure of technical results and a comradery of members greater than that in any other profession. No profession is so subject to the capriciousness of fortune, and he whose position is assured to-day is not assured to-morrow unless it be coupled with a consideration of those members not so fortunate. Especially is there an obligation to the younger members that they may have opportunity of training and a right start in the work.
The very essence of the profession is that it calls upon its members to direct men. They are the officers in the great industrial army. From the nature of things, metal mines do not, like our cities and settlements, lie in those regions covered deep in rich soils. Our mines must be found in the mountains and deserts where rocks are exposed to search. Thus they lie away from the centers of comfort and culture,—they are the outposts of civilization. The engineer is an officer on outpost duty, and in these places he is the camp leader. By his position as a leader in the community he has a chieftainship that carries a responsibility besides mere mine management. His is the responsibility of example in fair dealing and good government in the community.
In but few of its greatest works does the personality of its real creator reach the ears of the world; the real engineer does not advertise himself. But the engineering profession generally rises yearly in dignity and importance as the rest of the world learns more of where the real brains of industrial progress are. The time will come when people will ask, not who paid for a thing, but who built it.
To the engineer falls the work of creating from the dry bones of scientific fact the living body of industry. It is he whose intellect and direction bring to the world the comforts and necessities of daily need. Unlike the doctor, his is not the constant struggle to save the weak. Unlike the soldier, destruction is not his prime function. Unlike the lawyer, quarrels are not his daily bread. Engineering is the profession of creation and of construction, of stimulation of human effort and accomplishment.
INDEX.
Accounts, [169].
Administration, [161], [169], [178].
Administrative reports, [178].
Air-compression, [146].
-drills, [147].
Alteration, secondary, [24], [25], [26], [30].
Alternative shafts to inclined deposit, [63].
Amortization of capital and interest, [42].
Animals for underground transport, [134].
Annual demand for base metals, [38].
report, [179].
Artificial pillars, [121].
Assay foot, [10].
inch, [10].
of samples, [7].
Assaying, [177].
A value of mine, [56].
Averages, calculation, [1], [8].
Bailing, [143].
Balance sheet, [179].
value of mine, [182].
Benches, [95].
Bend in combined shafts, [59].
Bins, [84].
Blocked-out ore, [18].
Blocks, [13].
Bonanzas, origin, [28].
Bonus systems, of work, [167].
Breaking ore, [115].
Broken Hill, levels, [119].
ore-pillars, [120].
Cable-ways, [135].
Cages, [132].
Calculation of averages, [1], [8].
of quantities of ore, [13].
Capital expenditure, [170].
Caving systems, [122].
Churn-drills, [92].
Chutes, loading, in vertical shaft, [86].
Classification of ore in sight, [13], [16].
Combined shaft, [58], [67], [68], [69], [70], [72].
Commercial value of projects, determination, [188].
Compartments for shaft, [76].
Compressed-air locomotives, [135].
-air pumps, [141].
vs. electricity for drills, [145].
Content, average metal, determining, [1].
metal, differences, [6].
Contract work, [165].
Copper, annual demand, [38].
deposits, [1].
ores, enrichment, [30].
Cost of entry into mine, [65].
of equipment, [156].
per foot of sinking, [64].
Crosscuts, [86].
Cross-section of inclined deposit which must be attacked in depth, [68].
showing auxiliary vertical outlet, [66].
Crouch, J. J., [145].
Cubic feet per ton of ore, [14], [15].
foot contents of block, [13].
Deep-level mines, [60].
Demand for metals, [35].
Departmental dissection of expenditures, [171].
Deposits, in situ, [1].
ore, classes, [24].
regularity, [88].
size, [30].
structure, [24].
Depth of exhaustion, [21], [32].
Determination of average metal contents of ore, [3].
Development in early prospecting stage, [92].
in neighboring mines, [21], [31].
Diamond-drilling, [93].
Diluting narrow samples to a stoping width, [11].
Dip, [89].
Direct-acting steam-pumps, [140].
Distribution of values, [30].
Dividend, annual, present value, [46].
Dommeiler, [145].
Down holes, [100].
Drainage [138].
comparison of different systems, [143].
systems, [140].
Drifts, [87].
Drill, requirements, [145].
Drives, [87].
Dry walling with timber caps, [91].
Efficiency, factors of, [162].
of mass, [162].
Electrical haulage, [135].
pumps, [141].
Electricity for drills, [145].
Engine, size for winding appliances, [131].
Engineer, mining, as executive, [190].
Engineering projects, phases of, [187].
at cross-veins, [24].
Entry, to mine, [58].
to vertical or horizontal deposits, [62], [63].
Equipment, cost, [156].
improvements, [152].
Error, percentage in estimates from sampling, [1], [11].
Escape, [73].
Examination of mining property, [54].
Excavation, supporting, [103].
Exhaustion, depth, [32].
Expenditures, departmental dissection, [171].
mine, [170].
Extension in depth, [21], [22], [28].
Factor of safety in calculating averages of samples, [12].
Filling, [112].
system combined with square-setting, [111].
with broken ore subsequently withdrawn, [112].
waste, [107].
Fissure veins, [24].
Fissuring, [23].
depth, [30].
Flat-back stope, [98], [100], [110].
Flexibility in drainage system, [138].
Floors, [31].
Folding, [23].
Foot-drilled system of contract work, [166].
-hole system of contract work, [166].
of advance system of contract work, [166].
value, [10].
Fraud, precautions against in sampling, [7].
General expenses, [173].
Gold deposits, [1].
deposits, alteration, [29], [30].
enrichment, [28].
Hammer type of drill, [147], [148], [149].
Hand-drilling, [149].
-trucking, [133].
Haulage, electrical, [135].
equipment in shaft, [132].
mechanical, [134].
Hole system of contract work, [165].
Horizons of ore-deposits, [26].
Horizontal deposits, entry, [62].
stope, [98].
filled with waste, [108].
Hydraulic pumps, [142].
Impregnation deposits, [24].
Inch, assay, [10].
Inclined deposits to be worked from outcrop or near it, [62].
deposits which must be attacked in depth, [67].
shaft, [64].
Inclines, [65], [66], [67], [68].
Infiltration type of deposits, [24].
Intelligence as factor of skill, [163], [164].
Interest calculations in mine valuation, [43].
Iron hat, [27].
leaching, [27].
Ivanhoe mine, West Australia, [112].
Kibble, [132].
Labor, general technical data, [176].
handling, [161].
unions, [167].
Lateral underground transport, [133].
Le Roi mine, [112].
Lead, annual demand, [38].
deposits, [1].
enriching, [27].
prices, 1884-1908, [36].
-zinc ores, enrichment, [30].
Lenses, [24].
Levels, [87].
of Broken Hill, [119].
protection, [90].
Life, in sight, [44].
of mine, [157].
Locomotives, compressed-air, [135].
Lode mines, valuation, [1].
Lodes, [24].
Long-wall stope, [98].
Machine-drill, performance, [149].
drilling, [145].
vs. hand-drilling, [149].
Management, mine, [161].
Matte, [123].
Mechanical efficiency of drainage machinery, [139].
equipment, [124], [134], [138], [145].
Men for underground transport, [133].
Metal content, determining, [1], [3].
contents, differences, [6].
demand for, [35].
mine, value, [1].
Mines compared to other commercial enterprises, [183].
equipment, [124].
expenditures, [170].
Mines—continued.
life of, [157].
metal, value of, [1].
of moderate depths, [62].
to be worked to great depths, [62], [69].
valuation, [1], [13], [21], [34], [42], [51].
Mining engineering profession, [185].
Mt. Cenis tunnel, [145].
Morgan gold mine, [26].
Obligations of engineering profession, [192].
Openings, position in relation to secondary alteration, [23], [25].
Ore, average width in block, [13].
blocked-out, [17].
-bodies, [23].
shapes, [8].
-breaking, methods, [94], [95].
calculation of quantities of, [13].
-chutes in shrinkage-stoping, [115].
-deposits, classes, [24].
determination of average metal contents, [3].
developed, [17].
developing, [17].
expectant, [17].
sight, classification, [13], [16].
support in narrow stopes, [118].
-shoots, [23].
weight of a cubic foot, [14].
width for one sample, [5].
Origin of deposit, [23].
Outcrop mines, [60].
Output, factors limiting, [155].
giving least production cost, [154].
maximum, determination, [153].
Overhand stapes, [96], [98], [99].
Overproduction of base metal, [158].
Oxidation, [30].
Patchwork plant, mechanical inefficiency of, [158].
Pay areas, formation, [23].
Pillars, artificial, [121].
value of metal mine, [1].
Possible ore, [17].
Power conditions, [139].
general technical data, [176].
sources, [126].
transmission, [125], [126], [127], [145].
Preliminary inspection, [55].
Previous yield, [3].
Price of metals, [35].
Probable ore, [17], [19], [20], [21].
Producing stage of mine, [58].
Profit and loss account, [179].
factors determining, [2].
in sight, [16].
Proportional charges, [170].
Prospecting stage of mine, [58].
Prospective ore, [19].
value, [21].
Protection of levels, [90].
Pumping systems, [140].
Pumps, compressed-air, [141].
electrical, [141].
hydraulic, [142].
rod-driven, [142].
Ratio of output to mine, [153].
Recoverable percentage of gross assay value, [34].
Recovery of ore, [107].
Rectangular shaft, [74].
Redemption of capital and interest, [42].
Reduction of output, [158].
Regularity of deposit, [88].
Reliability of drainage system, [139].
Replacement, [24].
Reports, [56].
administrative, [178].
Resuing, [101].
Revenue account, [179].
Rill-cut overhand stope, [99].
method of incline cuts, [100].
filled with waste, [108].
-stoping, [96], [98], [99], [100], [137].
Risk in mining investments, [181].
in valuation of mines, [181].
Roadways, protecting in shrinkage-stoping, [114].
Rod-driven pumps, [142].
Rotary steam-pumps, [140].
Round vertical shafts, [74].
Runs of value, [8].
test-treatment, [3].
Safety, factor of, in calculating averages of samples, [12].
Sample, assay of, [7].
average value, [9].
narrow, diluting to a stoping width, [11].
taking, physical details, [6].
manner of taking, [4].
Sampling, [1], [3], [4], [5], [56], [177].
accuracy, [5].
percentage of error in estimates from, [11].
precautions against fraud, [7].
Saving of fixed charges, [155].
Secondary alteration, [24], [25], [26], [30].
enrichment, [21].
Security of investment, [158].
Self-dumping skip, [77].
Sets, [91].
arrangement for very deep inclined shafts, [71].
different depths, [60].
haulage, [129].
location, [70].
number, [72].
output capacity, [77].
shape, [74].
Shrinkage-stope, [114], [115].
-stoping, [112].
advantages, [117].
disadvantages, [116].
when applicable, [116].
Silver deposits, [1].
deposits, enrichment, [28], [30].
prices, [38].
Sinking, speed, [80].
Size of deposit, [30].
Skill, effect on production cost, [163].
balanced, [129].
haulage in vertical shaft, [85].
Sollars, [109].
Solubility of minerals, [27].
Specific volume of ores, [14].
Speculative values of metal mine, [1].
value of mine, [57].
Spelter, annual demand, [38].
-set timbering, [104].
Stations, [84].
arrangement for skip haulage in vertical shaft, [85], [87].
Steam-pumps, direct, [140].
Steepening winzes and ore passes, [111].
Stope filled with broken ore, [113].
minimum width, [101].
contract systems, [166].
Storing metal, [158].
Structural character of deposit, [23].
Structure of deposit, [24].
Stull and waste pillars, [121].
support with waste reënforcement, [120].
-supported stope, [104].
Stulls, [103].
wood, [91].
Subheading, [90].
Sublevel caving system, [122].
Subsidiary development, [84].
Superficial enrichment, [29].
Supplies, general technical data, [176].
Support by pillars of ore, [118].
Supporting excavation, [103].
Surveys, [176].
Suspense charges, [170].
Test parcels, [4].
sections, [6].
-treatment runs, [3].
Timber, cost, [77].
Timbered shaft design, [75].
Tin, annual demand, [38].
deposits, [1].
ore, migration and enrichment, [29].
Tools, [128].
Top slicing, [123].
Tracks, [135].
Transport in stopes, [136].
Tunnel entry, [81].
feet paid for in [10] years, [82].
size, [82].
Uppers, [100].
Valuation, mine, [2], [13], [21], [34], [42], [51].
of lode mines, [1].
mines, risk in, [181].
mines with little or no ore in sight, [51].
on second-hand data, [52].
Value, average, of samples, [9].
discrepancy between estimated and actual, [12].
distribution, [31].
of extension in depth, estimating, [22].
positive, of metal mine, [1].
present, of an annual dividend, [46].
of $1 or £1, payable in — years, [47].
runs of, [8].
speculative, of metal mine, [1].
Valuing ore in course of breaking, [102].
Vertical deposits, entry, [62].
interval between levels, [88].
shafts, [62-70], [72], [85], [86].
capacity, [78].
Volume, specific, of ores, [14].
Waste-filled stope, [109].
Water-power, [126].
Weight per cubic foot of ore, [14], [15].
Weindel, Caspar, [145].
Whiting hoist, [131].
Width of ore for one sample, [5].
Winding appliances, [129].
in shrinkage-stoping, [113].
to be used for filling, [107].
inherent limitations in accuracy of, [174].
sheets, [176].
Workshops, [151].
Yield, previous, [3].
Years of life required to yield —% interest, [48].
Zinc deposits, [1].
leaching, [27].