BAILING.--Bailing deserves to be mention_Principles of Mining: Valuation, Organization and Administration

for under certain conditions it is a most useful system, and at

all times a mine should be equipped with tanks against accident

to the pumps. Where the amount of water is limited,--up to, say,

50,000 gallons daily,--and where the ore output of the mine permits

the use of the winding-engine for part of the time on water haulage,

there is in the method an almost total saving of capital outlay.

Inasmuch as the winding-engine, even when the ore haulage is finished

for the day, must be under steam for handling men in emergencies,

and as the labor of stokers, engine-drivers, shaft-men, etc., is

therefore necessary, the cost of power consumed by bailing is not

great, despite the low efficiency of winding-engines.

COMPARISON OF VARIOUS SYSTEMS.--If it is assumed that flexibility,

reliability, mechanical efficiency, and capital cost can each be

divided into four figures of relative importance,--_A_, _B_, _C_,

and _D_, with _A_ representing the most desirable result,--it is

possible to indicate roughly the comparative values of various

pumping systems. It is not pretended that the four degrees are of

equal import. In all cases the factor of general power conditions

on the mine may alter the relative positions.

====================================================================

-------------|------|----------|-----------|------|---------|-------

Flexibility. | _A_ | _A_ | _B_ | _D_ | _B_ | _A_

Reliability. | _B_ | _B_ | _B_ | _A_ | _D_ | _A_

Efficiency.| _C_ | _D_ | _B_ | _A_ | _C_ | _D_

Capital Cost | _A_ | _B_ | _B_ | _D_ | _D_ | --

====================================================================

As each mine has its special environment, it is impossible to formulate

any final conclusion on a subject so involved. The attempt would lead

to a discussion of a thousand supposititious cases and hypothetical

remedies. Further, the description alone of pumping machines would

fill volumes, and the subject will never be exhausted. The engineer

confronted with pumping problems must marshal all the alternatives,

count his money, and apply the tests of flexibility, reliability,

efficiency, and cost, choose the system of least disadvantages,

and finally deprecate the whole affair, for it is but a parasite

growth on the mine.

CHAPTER XIV.

Mechanical Equipment (_Concluded_).

MACHINE DRILLING: POWER TRANSMISSION; COMPRESSED AIR _VS_. ELECTRICITY;

AIR DRILLS; MACHINE _VS_. HAND DRILLING. WORK-SHOPS. IMPROVEMENT

IN EQUIPMENT.

For over two hundred years from the introduction of drill-holes

for blasting by Caspar Weindel in Hungary, to the invention of

the first practicable steam percussion drill by J. J. Crouch of

Philadelphia, in 1849, all drilling was done by hand. Since Crouch's

time a host of mechanical drills to be actuated by all sorts of

power have come forward, and even yet the machine-drill has not

reached a stage of development where it can displace hand-work

under all conditions. Steam-power was never adapted to underground

work, and a serviceable drill for this purpose was not found until

compressed air for transmission was demonstrated by Dommeiller

on the Mt. Cenis tunnel in 1861.

The ideal requirements for a drill combine:--

a. Power transmission adapted to underground conditions.

b. Lightness.

c. Simplicity of construction.

d. Strength.

e. Rapidity and strength of blow.

f. Ease of erection.

g. Reliability.

h. Mechanical efficiency.

i. Low capital cost.

No drill invented yet fills all these requirements, and all are

a compromise on some point.

POWER TRANSMISSION; COMPRESSED AIR _vs_. ELECTRICITY.--The only

transmissions adapted to underground drill-work are compressed

air and electricity, and as yet an electric-driven drill has not

been produced which meets as many of the requirements of the metal

miner as do compressed-air drills. The latter, up to date, have

superiority in simplicity, lightness, ease of erection, reliability,

and strength over electric machines. Air has another advantage in

that it affords some assistance to ventilation, but it has the

disadvantage of remarkably low mechanical efficiency. The actual

work performed by the standard 3-3/4-inch air-drill probably does

not amount to over two or three horse-power against from fifteen to

eighteen horse-power delivered into the compressor, or mechanical

efficiency of less than 25%. As electrical power can be delivered to

the drill with much less loss than compressed air, the field for a

more economical drill on this line is wide enough to create eventually

the proper tool to apply it. The most satisfactory electric drill

produced has been the Temple drill, which is really an air-drill

driven by a small electrically-driven compressor placed near the

drill itself. But even this has considerable deficiencies in mining

work; the difficulties of setting up, especially for stoping work,

and the more cumbersome apparatus to remove before blasting are

serious drawbacks. It has deficiencies in reliability and greater

complication of machinery than direct air.

AIR-COMPRESSION.--The method of air-compression so long accomplished

only by power-driven pistons has now an alternative in some situations

by the use of falling water. This latter system is a development

of the last twelve years, and, due to the low initial outlay and

extremely low operating costs, bids fair in those regions where

water head is available not only to displace the machine compressor,

but also to extend the application of compressed air to mine motors

generally, and to stay in some environments the encroachment of

electricity into the compressed-air field. Installations of this

sort in the West Kootenay, B.C., and at the Victoria copper mine,

Michigan, are giving results worthy of careful attention.

Mechanical air-compressors are steam-, water-, electrical-, and

gas-driven, the alternative obviously depending on the source and

cost of power. Electrical- and gas- and water-driven compressors

work under the disadvantage of constant speed motors and respond

little to the variation in load, a partial remedy for which lies

in enlarged air-storage capacity. Inasmuch as compressed air, so

far as our knowledge goes at present, must be provided for drills,

it forms a convenient transmission of power to various motors

underground, such as small pumps, winches, or locomotives. As stated

in discussing those machines, it is not primarily a transmission

of even moderate mechanical efficiency for such purposes; but as

against the installation and operation of independent transmission,

such as steam or electricity, the economic advantage often compensates

the technical losses. Where such motors are fixed, as in pumps

and winches, a considerable gain in efficiency can be obtained by

reheating.

It is not proposed to enter a discussion of mechanical details of

air-compression, more than to call attention to the most common

delinquency in the installation of such plants. This deficiency

lies in insufficient compression capacity for the needs of the

mine and consequent effective operation of drills, for with under

75 pounds pressure the drills decrease remarkably in rapidity of

stroke and force of the blow. The consequent decrease in actual

accomplishment is far beyond the ratio that might be expected on

the basis of mere difference of pressure. Another form of the same

chronic ill lies in insufficient air-storage capacity to provide

for maintenance of pressure against moments when all drills or

motors in the mine synchronize in heavy demand for air, and thus

lower the pressure at certain periods.

AIR-DRILLS.--Air-drills are from a mechanical point of view broadly

of two types,--the first, in which the drill is the piston extension;

and the second, a more recent development for mining work, in which

the piston acts as a hammer striking the head of the drill. From an

economic point of view drills may be divided into three classes.

First, heavy drills, weighing from 150 to 400 pounds, which require

two men for their operation; second, "baby" drills of the piston type,

weighing from 110 to 150 pounds, requiring one man with occasional

assistance in setting up; and third, very light drills almost wholly

of the hammer type. This type is built in two forms: a heavier

type for mounting on columns, weighing about 80 pounds; and a type

after the order of the pneumatic riveter, weighing as low as 20

pounds and worked without mounting.

The weight and consequent mobility of a drill, aside from labor

questions, have a marked effect on costs, for the lighter the drill

the less difficulty and delay in erection, and consequent less

loss of time and less tendency to drill holes from one radius,

regardless of pointing to take best advantage of breaking planes.

Moreover, smaller diameter and shorter holes consume less explosives

per foot advanced or per ton broken. The best results in tonnage

broken and explosive consumed, if measured by the foot of drill-hole

necessary, can be accomplished from hand-drilling and the lighter

the machine drill, assuming equal reliability, the nearer it

approximates these advantages.

The blow, and therefore size and depth of hole and rapidity of

drilling, are somewhat dependent upon the size of cylinders and

length of stroke, and therefore the heavier types are better adapted

to hard ground and to the deep holes of some development points.

Their advantages over the other classes lie chiefly in this ability

to bore exceedingly hard material and in the greater speed of advance

possible in development work; but except for these two special

purposes they are not as economical per foot advanced or per ton

of ore broken as the lighter drills.

The second class, where men can be induced to work them one man per

drill, saves in labor and gains in mobility. Many tests show great

economy of the "baby" type of piston drills in average ground over

the heavier machines for stoping and for most lateral development.

All piston types are somewhat cumbersome and the heavier types

require at least four feet of head room. The "baby" type can be

operated in less space than this, but for narrow stopes they do

not lend themselves with the same facility as the third class.

The third class of drills is still in process of development, but

it bids fair to displace much of the occupation of the piston types

of drill. Aside from being a one-man drill, by its mobility it

will apparently largely reproduce the advantage of hand-drilling

in ability to place short holes from the most advantageous angles

and for use in narrow places. As compared with other drills it

bids fair to require less time for setting up and removal and for

change of bits; to destroy less steel by breakages; to dull the

bits less rapidly per foot of hole; to be more economical of power;

to require much less skill in operation, for judgment is less called

upon in delivering speed; and to evade difficulties of fissured

ground, etc. And finally the cost is only one-half, initially and

for spares. Its disadvantage so far is a lack of reliability due to

lightness of construction, but this is very rapidly being overcome.

This type, however, is limited in depth of hole possible, for,

from lack of positive reverse movement, there is a tendency for

the spoil to pack around the bit, and as a result about four feet

seems the limit.

The performance of a machine-drill under show conditions may be

anything up to ten or twelve feet of hole per hour on rock such

as compact granite; but in underground work a large proportion of

the time is lost in picking down loose ore, setting up machines,

removal for blasting, clearing away spoil, making adjustments,

etc. The amount of lost time is often dependent upon the width of

stope or shaft and the method of stoping. Situations which require

long drill columns or special scaffolds greatly accentuate the loss

of time. Further, the difficulties in setting up reflect indirectly

on efficiency to a greater extent in that a larger proportion of

holes are drilled from one radius and thus less adapted to the

best breaking results than where the drill can easily be reset from

various angles.

The usual duty of a heavy drill per eight-hour shift using two men

is from 20 to 40 feet of hole, depending upon the rock, facilities

for setting up, etc., etc.[*] The lighter drills have a less average

duty, averaging from 15 to 25 feet per shift.

[Footnote *: Over the year 1907 in twenty-eight mines compiled

from Alaska to Australia, an average of 23.5 feet was drilled per

eight-hour shift by machines larger than three-inch cylinder.]

MACHINE _vs_. HAND-DRILLING.--The advantages of hand-drilling over

machine-drilling lie, first, in the total saving of power, the

absence of capital cost, repairs, depreciation, etc., on power,

compresser and drill plant; second, the time required for setting

up machine-drills does not warrant frequent blasts, so that a number

of holes on one radius are a necessity, and therefore machine-holes

generally cannot be pointed to such advantage as hand-holes. Hand-holes

can be set to any angle, and by thus frequent blasting yield greater

tonnage per foot of hole. Third, a large number of comparative

statistics from American, South African, and Australian mines show

a saving of about 25% in explosives for the same tonnage or foot

of advance by hand-holes over medium and heavy drill-holes.

The duty of a skilled white man, single-handed, in rock such as

is usually met below the zone of oxidation, is from 5 to 7 feet

per shift, depending on the rock and the man. Two men hand-drilling

will therefore do from 1/4 to 2/3 of the same footage of holes

that can be done by two men with a heavy machine-drill, and two

men hand-drilling will do from 1/5 to 1/2 the footage of two men

with two light drills.

The saving in labor of from 75 to 33% by machine-drilling may or

may not be made up by the other costs involved in machine-work.

The comparative value of machine- and hand-drilling is not subject

to sweeping generalization. A large amount of data from various

parts of the world, with skilled white men, shows machine-work

to cost from half as much per ton or foot advanced as hand-work

to 25% more than handwork, depending on the situation, type of

drill, etc. In a general way hand-work can more nearly compete

with heavy machines than light ones. The situations where hand-work

can compete with even light machines are in very narrow stopes where

drills cannot be pointed to advantage, and where the increased

working space necessary for machine drills results in breaking more

waste. Further, hand-drilling can often compete with machine-work

in wide stopes where long columns or platforms must be used and

therefore there is much delay in taking down, reërection, etc.

Many other factors enter into a comparison, however, for

machine-drilling produces a greater number of deeper holes and

permits larger blasts and therefore more rapid progress. In driving

levels under average conditions monthly footage is from two to

three times as great with heavy machines as by hand-drilling, and

by lighter machines a somewhat less proportion of greater speed.

The greater speed obtained in development work, the greater tonnage

obtained per man in stoping, with consequent reduction in the number

of men employed, and in reduction of superintendence and general

charges are indirect advantages for machine-drilling not to be

overlooked.

The results obtained in South Africa by hand-drilling in shafts,

and its very general adoption there, seem to indicate that better

speed and more economical work can be obtained in that way in very

large shafts than by machine-drilling. How far special reasons

there apply to smaller shafts or labor conditions elsewhere have

yet to be demonstrated. In large-dimension shafts demanding a large

number of machines, the handling of long machine bars and machines

generally results in a great loss of time. The large charges in

deep holes break the walls very irregularly; misfires cause more

delay; timbering is more difficult in the face of heavy blasting

charges; and the larger amount of spoil broken at one time delays

renewed drilling, and altogether the advantages seem to lie with

hand-drilling in shafts of large horizontal section.

The rapid development of special drills for particular conditions

has eliminated the advantage of hand-work in many situations during

the past ten years, and the invention of the hammer type of drill

bids fair to render hand-drilling a thing of the past. One

generalization is possible, and that is, if drills are run on 40-50

pounds' pressure they are no economy over hand-drilling.

WORKSHOPS.

In addition to the ordinary blacksmithy, which is a necessity,

the modern tendency has been to elaborate the shops on mines to

cover machine-work, pattern-making and foundry-work, in order that

delays may be minimized by quick repairs. To provide, however,

for such contingencies a staff of men must be kept larger than

the demand of average requirements. The result is an effort to

provide jobs or to do work extravagantly or unnecessarily well.

In general, it is an easy spot for fungi to start growing on the

administration, and if custom repair shops are available at all,

mine shops can be easily overdone.

A number of machines are now in use for sharpening drills.

Machine-sharpening is much cheaper than hand-work, although the drills

thus sharpened are rather less efficient owing to the difficulty of

tempering them to the same nicety; however, the net results are

in favor of the machines.

IMPROVEMENT IN EQUIPMENT.

Not only is every mine a progressive industry until the bottom

gives out, but the technology of the industry is always progressing,

so that the manager is almost daily confronted with improvements

which could be made in his equipment that would result in decreasing

expenses or increasing metal recovery. There is one test to the

advisability of such alterations: How long will it take to recover

the capital outlay from the savings effected? and over and above

this recovery of capital there must be some very considerable gain.

The life of mines is at least secured over the period exposed in

the ore-reserves, and if the proposed alteration will show its

recovery and profit in that period, then it is certainly justified.

If it takes longer than this on the average speculative ore-deposit,

it is a gamble on finding further ore. As a matter of practical

policy it will be found that an improvement in equipment which

requires more than three or four years to redeem itself out of

saving, is usually a mechanical or metallurgical refinement the

indulgence in which is very doubtful.

CHAPTER XV.

Ratio of Output to the Mine.

DETERMINATION OF THE POSSIBLE MAXIMUM; LIMITING FACTORS; COST OF

EQUIPMENT; LIFE OF THE MINE; MECHANICAL INEFFICIENCY OF PATCHWORK

PLANT; OVERPRODUCTION OF BASE METAL; SECURITY OF INVESTMENT.

The output obtainable from a given mine is obviously dependent

not only on the size of the deposit, but also on the equipment

provided,--in which equipment means the whole working appliances,

surface and underground.

A rough and ready idea of output possibilities of inclined deposits

can be secured by calculating the tonnage available per foot of

depth from the horizontal cross-section of the ore-bodies exposed

and assuming an annual depth of exhaustion, or in horizontal deposits

from an assumption of a given area of exhaustion. Few mines, at the

time of initial equipment, are developed to an extent from which

their possibilities in production are evident, for wise finance

usually leads to the erection of some equipment and production before

development has been advanced to a point that warrants a large or

final installation. Moreover, even were the full possibilities of

the mine known, the limitations of finance usually necessitate a

less plant to start with than is finally contemplated. Therefore

output and equipment are usually growing possibilities during the

early life of a mine.

There is no better instance in mine engineering where pure theory

must give way to practical necessities of finance than in the

determination of the size of equipment and therefore output. Moreover,

where finance even is no obstruction, there are other limitations

of a very practical order which must dominate the question of the

size of plant giving the greatest technical economy. It is, however,

useful to state the theoretical considerations in determining the

ultimate volume of output and therefore the size of equipments,

for the theory will serve to illuminate the practical limitations.

The discussion will also again demonstrate that all engineering

is a series of compromises with natural and economic forces.

OUTPUT GIVING LEAST PRODUCTION COST.--As one of the most important

objectives is to work the ore at the least cost per ton, it is

not difficult to demonstrate that the minimum working costs can

be obtained only by the most intensive production. To prove this,

it need only be remembered that the working expenses of a mine

are of two sorts: one is a factor of the tonnage handled, such as

stoping and ore-dressing; the other is wholly or partially dependent

upon time. A large number of items are of this last order. Pumping

and head-office expenses are almost entirely charges independent

of the tonnage handled. Superintendence and staff salaries and

the like are in a large proportion dependent upon time. Many other

elements of expense, such as the number of engine-drivers, etc., do

not increase proportionately to increase in tonnage. These charges,

or the part of them dependent upon time apart from tonnage, may be

termed the "fixed charges."

There is another fixed charge more obscure yet no less certain.

Ore standing in a mine is like money in a bank drawing no interest,

and this item of interest may be considered a "fixed charge," for

if the ore were realized earlier, this loss could be partially

saved. This subject is further referred to under "Amortization."

If, therefore, the time required to exhaust the mine be prolonged

by the failure to maintain the maximum output, the total cost of

working it will be greater by the fixed charges over such an increased

period. Conversely, by equipping on a larger scale, the mine will

be exhausted more quickly, a saving in total cost can be made, and

the ultimate profit can be increased by an amount corresponding

to the time saved from the ravages of fixed charges. In fine, the

working costs may be reduced by larger operations, and therefore

the value of the mine increased.

The problem in practice usually takes the form of the relative

superiority of more or of fewer units of plant, and it can be considered

in more detail if the production be supposed to consist of units

averaging say 100 tons per day each. The advantage of more units

over less will be that the extra ones can be produced free of fixed

charges, for these are an expense already involved in the lesser

units. This extra production will also enjoy the interest which

can be earned over the period of its earlier production. Moreover,

operations on a larger scale result in various minor economies

throughout the whole production, not entirely included in the type

of expenditure mentioned as "fixed charges." We may call these

various advantages the "saving of fixed charges" due to larger-scale

operations. The saving of fixed charges amounts to very considerable

sums. In general the items of working cost alone, mentioned above,

which do not increase proportionately to the tonnage, aggregate

from 10 to 25% of the total costs. Where much pumping is involved,

the percentage will become even greater.

The question of the value of the mine as affected by the volume

of output becomes very prominent in low-grade mines, where, if

equipped for output on too small a scale, no profits at all could

be earned, and a sufficient production is absolutely imperative

for any gain. There are many mines in every country which with

one-third of their present rate of production would lose money.

That is, the fixed charges, if spread over small output, would be

so great per ton that the profit would be extinguished by them.

In the theoretical view, therefore, it would appear clear that

the greatest ultimate profit from a mine can be secured only by

ore extraction under the highest pressure. As a corollary to this

it follows that development must proceed with the maximum speed.

Further, it follows that the present value of a mine is at least

partially a factor of the volume of output contemplated.

FACTORS LIMITING THE OUTPUT.

Although the above argument can be academically defended, there

are, as said at the start, practical limitations to the maximum

intensity of production, arising out of many other considerations

to which weight must be given. In the main, there are five principal

limitations:--

1. Cost of equipment.

2. Life of the mine.

3. Mechanical inefficiency of patchwork plant.

4. Overproduction of base metal.

5. Security of investment.

COST OF EQUIPMENT.--The "saving of fixed charges" can only be obtained

by larger equipment, which represents an investment. Mining works,

shafts, machinery, treatment plants, and all the paraphernalia cost

large sums of money. They become either worn out or practically

valueless through the exhaustion of the mines. Even surface machinery

when in good condition will seldom realize more than one-tenth of its

expense if useless at its original site. All mines are ephemeral;

therefore virtually the entire capital outlay of such works must

be redeemed during the life of the mine, and the interest on it

must also be recovered.

The certain life, with the exception of banket and a few other

types of deposit, is that shown by the ore in sight, plus something

for extension of the deposit beyond exposures. So, against the

"savings" to be made, must be set the cost of obtaining them, for

obviously it is of no use investing a dollar to save a total of

ninety cents. The economies by increased production are, however,

of such an important character that the cost of almost any number

of added units (within the ability of the mine to supply them)

can be redeemed from these savings in a few years. For instance,

in a Californian gold mine where the working expenses are $3 and

the fixed charges are at the low rate of 30 cents per ton, one

unit of increased production would show a saving of over $10,000

per annum from the saving of fixed charges. In about three years

this sum would repay the cost of the additional treatment equipment.

If further shaft capacity were required, the period would be much

extended. On a Western copper mine, where the costs are $8 and the

fixed charges are 80 cents per ton, one unit of increased production

would effect a saving of the fixed charges equal to the cost of

the extra unit in about three years. That is, the total sum would

amount to $80,000, or enough to provide almost any type of mechanical

equipment for such additional tonnage.

The first result of vigorous development is to increase the ore in

sight,--the visible life of the mine. When such visible life has

been so lengthened that the period in which the "saving of fixed

charges" will equal the amount involved in expansion of equipment,

then from the standpoint of this limitation only is the added

installation justified. The equipment if expanded on this practice

will grow upon the heels of rapid development until the maximum

production from the mine is reached, and a kind of equilibrium

establishes itself.

Conversely, this argument leads to the conclusion that, regardless

of other considerations, an equipment, and therefore output, should

not be expanded beyond the redemption by way of "saving from fixed

charges" of the visible or certain life of the mine. In those mines,

such as at the Witwatersrand, where there is a fairly sound assurance

of definite life, it is possible to calculate at once the size of

plant which by saving of "fixed charges" will be eventually the

most economical, but even here the other limitations step in to

vitiate such policy of management,--chiefly the limitation through

security of investment.

LIFE OF THE MINE.--If carried to its logical extreme, the above

program means a most rapid exhaustion of the mine. The maximum output

will depend eventually upon the rapidity with which development

work may be extended. As levels and other subsidiary development

openings can be prepared in inclined deposits much more quickly

than the shaft can be sunk, the critical point is the shaft-sinking.

As a shaft may by exertion be deepened at least 400 feet a year on

a going mine, the provision of an equipment to eat up the ore-body

at this rate of sinking means very early exhaustion indeed. In

fact, had such a theory of production been put into practice by

our forefathers, the mining profession might find difficulty in

obtaining employment to-day. Such rapid exhaustion would mean a

depletion of the mineral resources of the state at a pace which

would be alarming.

MECHANICAL INEFFICIENCY OF PATCHWORK PLANT.--Mine equipments on

speculative mines (the vast majority) are often enough patchwork,

for they usually grow from small beginnings; but any scheme of

expansion based upon the above doctrine would need to be modified

to the extent that additions could be in units large in ratio to

previous installations, or their patchwork character would be still

further accentuated. It would be impossible to maintain mechanical

efficiency under detail expansion.

OVERPRODUCTION OF BASE METAL.--Were this intensity of production of

general application to base metal mines it would flood the markets,

and, by an overproduction of metal depress prices to a point where

the advantages of such large-scale operations would quickly vanish.

The theoretical solution in this situation would be, if metals

fell below normal prices, let the output be reduced, or let the

products be stored until the price recovers. From a practical point

of view either alternative is a policy difficult to face.

In the first case, reduction of output means an increase of working

expenses by the spread of fixed charges over less tonnage, and

this in the face of reduced metal prices. It may be contended,

however, that a falling metal market is usually the accompaniment

of a drop in all commodities, wherefore working costs can be reduced

somewhat in such times of depression, thereby partially compensating

the other elements making for increased costs. Falls in commodities

are also the accompaniment of hard times. Consideration of one's

workpeople and the wholesale slaughter of dividends to the then

needy stockholders, resulting from a policy of reduced production,

are usually sufficient deterrents to diminished output.

The second alternative, that of storing metal, means equally a

loss of dividends by the investment of a large sum in unrealized

products, and the interest on this sum. The detriment to the market

of large amounts of unsold metal renders such a course not without

further disadvantages.

SECURITY OF INVESTMENT.--Another point of view antagonistic to

such wholesale intensity of production, and one worthy of careful

consideration, is that of the investor in mines. The root-value of

mining stocks is, or should be, the profit in sight. If the policy

of greatest economy in production costs be followed as outlined

above, the economic limit of ore-reserves gives an apparently very

short life, for the ore in sight will never represent a life beyond

the time required to justify more plant. Thus the "economic limit

of ore in reserve" will be a store equivalencing a period during

which additional equipment can be redeemed from the "saving of

fixed charges," or three or four years, usually.

The investor has the right to say that he wants the guarantee of

longer life to his investment,--he will in effect pay insurance for

it by a loss of some ultimate profit. That this view, contradictory

to the economics of the case, is not simply academic, can be observed

by any one who studies what mines are in best repute on any stock

exchange. All engineers must wish to have the industry under them

in high repute. The writer knows of several mines paying 20% on

their stocks which yet stand lower in price on account of short

ore-reserves than mines paying less annual returns. The speculator,

who is an element not to be wholly disregarded, wishes a rise in

his mining stock, and if development proceeds at a pace in advance

of production, he will gain a legitimate rise through the increase

in ore-reserves.

The investor's and speculator's idea of the desirability of a proved

long life readily supports the technical policy of high-pressure

development work, but not of expansion of production, for they

desire an increasing ore-reserve. Even the metal operator who is

afraid of overproduction does not object to increased ore-reserves.

On the point of maximum intensity of development work in a mine all

views coincide. The mining engineer, if he takes a Machiavellian

view, must agree with the investor and the metal dealer, for the

engineer is a "fixed charge" the continuance of which is important

to his daily needs.

The net result of all these limitations is therefore an invariable

compromise upon some output below the possible maximum. The initial

output to be contemplated is obviously one upon which the working

costs will be low enough to show a margin of profit. The medium

between these two extremes is determinable by a consideration of

the limitations set out,--and the cash available. When the volume

of output is once determined, it must be considered as a factor

in valuation, as discussed under "Amortization."

CHAPTER XVI.

Administration.

LABOR EFFICIENCY; SKILL; INTELLIGENCE; APPLICATION COORDINATION;

CONTRACT WORK; LABOR UNIONS; REAL BASIS OF WAGES.

The realization from a mine of the profits estimated from the other

factors in the case is in the end dependent upon the management.

Good mine management is based upon three elementals: first, sound

engineering; second, proper coördination and efficiency of every human

unit; third, economy in the purchase and consumption of supplies.

The previous chapters have been devoted to a more or less extended

exposition of economic engineering. While the second and third

requirements are equally important, they range in many ways out of

the engineering and into the human field. For this latter reason

no complete manual will ever be published upon "How to become a

Good Mine Manager."

It is purposed, however, to analyze some features of these second

and third fundamentals, especially in their interdependent phases,

and next to consider the subject of mine statistics, for the latter

are truly the microscopes through which the competence of the

administration must be examined.

The human units in mine organization can be divided into officers

and men. The choice of mine officers is the assembling of specialized

brains. Their control, stimulation, and inspiration is the main work

of the administrative head. Success in the selection and control of

staff is the index of executive ability. There are no mathematical,

mechanical, or chemical formulas for dealing with the human mind

or human energies.

LABOR.--The whole question of handling labor can be reduced to

the one term "efficiency." Not only does the actual labor outlay

represent from 60 to 70% of the total underground expenses, but

the capacity or incapacity of its units is responsible for wider

fluctuations in production costs than the bare predominance in

expenditure might indicate. The remaining expense is for supplies,

such as dynamite, timber, steel, power, etc., and the economical

application of these materials by the workman has the widest bearing

upon their consumption.

Efficiency of the mass is the resultant of that of each individual

under a direction which coördinates effectively all units. The

lack of effectiveness in one individual diminishes the returns

not simply from that man alone; it lowers the results from numbers

of men associated with the weak member through the delaying and

clogging of their work, and of the machines operated by them.

Coördination of work is a necessary factor of final efficiency. This

is a matter of organization and administration. The most zealous

stoping-gang in the world if associated with half the proper number

of truckers must fail to get the desired result.

Efficiency in the single man is the product of three factors,--skill,

intelligence, and application. A great proportion of underground

work in a mine is of a type which can be performed after a fashion

by absolutely unskilled and even unintelligent men, as witness the

breaking-in of savages of low average mentality, like the South

African Kaffirs. Although most duties can be performed by this

crudest order of labor, skill and intelligence can be applied to

it with such economic results as to compensate for the difference

in wage. The reason for this is that the last fifty years have seen

a substitution of labor-saving machines for muscle. Such machines

displace hundreds of raw laborers. Not only do they initially cost

large sums, but they require large expenditure for power and up-keep.

These fixed charges against the machine demand that it shall be

worked at its maximum. For interest, power, and up-keep go on in

any event, and the saving on crude labor displaced is not so great

but that it quickly disappears if the machine is run under its

capacity. To get its greatest efficiency, a high degree of skill

and intelligence is required. Nor are skill and intelligence alone

applicable to labor-saving devices themselves, because drilling and

blasting rock and executing other works underground are matters

in which experience and judgment in the individual workman count

to the highest degree.

How far skill affects production costs has had a thorough demonstration

in West Australia. For a time after the opening of those mines

only a small proportion of experienced men were obtainable. During

this period the rock broken per man employed underground did not

exceed the rate of 300 tons a year. In the large mines it has now,

after some eight years, attained 600 to 700 tons.

How far intelligence is a factor indispensable to skill can be well

illustrated by a comparison of the results obtained from working

labor of a low mental order, such as Asiatics and negroes, with those

achieved by American or Australian miners. In a general way, it may

be stated with confidence that the white miners above mentioned

can, under the same physical conditions, and with from five to ten

times the wage, produce the same economic result,--that is, an

equal or lower cost per unit of production. Much observation and

experience in working Asiatics and negroes as well as Americans

and Australians in mines, leads the writer to the conclusion that,

averaging actual results, one white man equals from two to three

of the colored races, even in the simplest forms of mine work such

as shoveling or tramming. In the most highly skilled branches,

such as mechanics, the average ratio is as one to seven, or in

extreme cases even eleven. The question is not entirely a comparison

of bare efficiency individually; it is one of the sum total of

results. In mining work the lower races require a greatly increased

amount of direction, and this excess of supervisors consists of

men not in themselves directly productive. There is always, too,

a waste of supplies, more accidents, and more ground to be kept

open for accommodating increased staff, and the maintenance of

these openings must be paid for. There is an added expense for

handling larger numbers in and out of the mine, and the lower

intelligence reacts in many ways in lack of coördination and inability

to take initiative. Taking all divisions of labor together, the

ratio of efficiency as measured in amount of output works out from

four to five colored men as the equivalent of one white man of the

class stated. The ratio of costs, for reasons already mentioned,

and in other than quantity relation, figures still more in favor

of the higher intelligence.

The following comparisons, which like all mine statistics must

necessarily be accepted with reservation because of some dissimilarity

of economic surroundings, are yet on sufficiently common ground

to demonstrate the main issue,--that is, the bearing of inherent

intelligence in the workmen and their consequent skill. Four groups

of gold mines have been taken, from India, West Australia, South

Africa, and Western America. All of those chosen are of the same

stoping width, 4 to 5 feet. All are working in depth and with every

labor-saving device available. All dip at about the same angle and

are therefore in much the same position as to handling rock. The

other conditions are against the white-manned mines and in favor of

the colored. That is, the Indian mines have water-generated electric

power and South Africa has cheaper fuel than either the American or

Australian examples. In both the white-manned groups, the stopes

are supported, while in the others no support is required.

=======================================================================

| Tons of | Average |Tons |

| Material | Number of Men | per |Cost per

Group of Mines | Excavated | Employed | Man | Ton of

|over Period|---------------| per |Material

----------------------------|-----------|-------|-------|-----|--------

Four Kolar mines[1] | 963,950 | 13,611| 302 | 69.3| $3.85

Six Australian mines[2] | 1,027,718 | -- | 1,534 |669.9| 2.47

Three Witwatersrand mines[3]| 2,962,640 | 13,560| 1,595 |195.5| 2.68

Five American mines[4] | 1,089,500 | -- | 1,524 |713.3| 1.92

=======================================================================

[Footnote 1: Indian wages average about 20 cents per day.]

[Footnote 2: White men's wages average about $3 per day.]

[Footnote 3: About two-fifths of the colored workers were negroes,

and three-fifths Chinamen. Negroes average about 60 cents, and

Chinamen about 45 cents per day, including keep.]

[Footnote 4: Wages about $3.50. Tunnel entry in two mines.]

[Footnote 5: Includes rock broken in development work.

In the case of the specified African mines, the white labor is

employed almost wholly in positions of actual or semi-superintendence,

such as one white man in charge of two or three drills.

In the Indian case, in addition to the white men who are wholly

in superintendence, there were of the natives enumerated some 1000

in positions of semi-superintendence, as contractors or headmen,

working-gangers, etc.]

One issue arises out of these facts, and that is that no engineer

or investor in valuing mines is justified in anticipating lower

costs in regions where cheap labor exists.

In supplement to sheer skill and intelligence, efficiency can be

gained only by the application of the man himself. A few months ago

a mine in California changed managers. The new head reduced the number

employed one-third without impairing the amount of work accomplished.

This was not the result of higher skill or intelligence in the men,

but in the manager. Better application and coördination were secured

from the working force. Inspiration to increase of exertion is

created less by "driving" than by recognition of individual effort,

in larger pay, and by extending justifiable hope of promotion. A

great factor in the proficiency of the mine manager is his ability

to create an _esprit-de-corps_ through the whole staff, down to

the last tool boy. Friendly interest in the welfare of the men

and stimulation by competitions between various works and groups

all contribute to this end.

CONTRACT WORK.--The advantage both to employer and employed of

piece work over wage needs no argument. In a general way, contract

work honorably carried out puts a premium upon individual effort,

and thus makes for efficiency. There are some portions of mine

work which cannot be contracted, but the development, stoping,

and trucking can be largely managed in this way, and these items

cover 65 to 75% of the total labor expenditure underground.

In development there are two ways of basing contracts,--the first

on the footage of holes drilled, and the second on the footage

of heading advanced. In contract-stoping there are four methods

depending on the feet of hole drilled, on tonnage, on cubic space,

and on square area broken.

All these systems have their rightful application, conditioned upon

the class of labor and character of the deposit.

In the "hole" system, the holes are "pointed" by some mine official

and are blasted by a special crew. The miner therefore has little

interest in the result of the breaking. If he is a skilled white

man, the hours which he has wherein to contemplate the face usually

enable him to place holes to better advantage than the occasional

visiting foreman. With colored labor, the lack of intelligence in

placing holes and blasting usually justifies contracts per "foot

drilled." Then the holes are pointed and blasted by superintending

men.

On development work with the foot-hole system, unless two working

faces can be provided for each contracting party, they are likely

to lose time through having finished their round of holes before the

end of the shift. As blasting must be done outside the contractor's

shifts, it means that one shift per day must be set aside for the

purpose. Therefore not nearly such progress can be made as where

working the face with three shifts. For these reasons, the "hole"

system is not so advantageous in development as the "foot of advance"

basis.

In stoping, the "hole" system has not only a wider, but a sounder

application. In large ore-bodies where there are waste inclusions,

it has one superiority over any system of excavation measurement,

namely, that the miner has no interest in breaking waste into the

ore.

The plan of contracting stopes by the ton has the disadvantage

that either the ore produced by each contractor must be weighed

separately, or truckers must be trusted to count correctly, and to

see that the cars are full. Moreover, trucks must be inspected for

waste,--a thing hard to do underground. So great are these detailed

difficulties that many mines are sending cars to the surface in

cages when they should be equipped for bin-loading and self-dumping

skips.

The method of contracting by the cubic foot of excavation saves

all necessity for determining the weight of the output of each

contractor. Moreover, he has no object in mixing waste with the ore,

barring the breaking of the walls. This system therefore requires

the least superintendence, permits the modern type of hoisting,

and therefore leaves little justification for the survival of the

tonnage basis.

Where veins are narrow, stoping under contract by the square foot

or fathom measured parallel to the walls has an advantage. The miner

has no object then in breaking wall-rock, and the thoroughness of

the ore-extraction is easily determined by inspection.

BONUS SYSTEMS.--By giving cash bonuses for special accomplishment,

much the same results can be obtained in some departments as by

contracting. A bonus per foot of heading gained above a minimum,

or an excess of trucks trammed beyond a minimum, or prizes for

the largest amount done during the week or month in special works

or in different shifts,--all these have a useful application in

creating efficiency. A high level of results once established is

easily maintained.

LABOR UNIONS.--There is another phase of the labor question which

must be considered and that is the general relations of employer

and employed. In these days of largely corporate proprietorship,

the owners of mines are guided in their relations with labor by

engineers occupying executive positions. On them falls the

responsibility in such matters, and the engineer becomes thus a

buffer between labor and capital. As corporations have grown, so

likewise have the labor unions. In general, they are normal and

proper antidotes for unlimited capitalistic organization.

Labor unions usually pass through two phases. First, the inertia

of the unorganized labor is too often stirred only by demagogic

means. After organization through these and other agencies, the

lack of balance in the leaders often makes for injustice in demands,

and for violence to obtain them and disregard of agreements entered

upon. As time goes on, men become educated in regard to the rights

of their employers, and to the reflection of these rights in ultimate

benefit to labor itself. Then the men, as well as the intelligent

employer, endeavor to safeguard both interests. When this stage

arrives, violence disappears in favor of negotiation on economic

principles, and the unions achieve their greatest real gains. Given

a union with leaders who can control the members, and who are disposed

to approach differences in a business spirit, there are few sounder

positions for the employer, for agreements honorably carried out

dismiss the constant harassments of possible strikes. Such unions

exist in dozens of trades in this country, and they are entitled to

greater recognition. The time when the employer could ride roughshod

over his labor is disappearing with the doctrine of "_laissez faire_,"

on which it was founded. The sooner the fact is recognized, the

better for the employer. The sooner some miners' unions develop

from the first into the second stage, the more speedily will their

organizations secure general respect and influence.[*]

[Footnote *: Some years of experience with compulsory arbitration

in Australia and New Zealand are convincing that although the law

there has many defects, still it is a step in the right direction,

and the result has been of almost unmixed good to both sides. One

of its minor, yet really great, benefits has been a considerable

extinction of the parasite who lives by creating violence.]

The crying need of labor unions, and of some employers as well,

is education on a fundamental of economics too long disregarded

by all classes and especially by the academic economist. When the

latter abandon the theory that wages are the result of supply and

demand, and recognize that in these days of international flow of

labor, commodities and capital, the real controlling factor in

wages is efficiency, then such an educational campaign may become

possible. Then will the employer and employee find a common ground

on which each can benefit. There lives no engineer who has not

seen insensate dispute as to wages where the real difficulty was

inefficiency. No administrator begrudges a division with his men

of the increased profit arising from increased efficiency. But

every administrator begrudges the wage level demanded by labor

unions whose policy is decreased efficiency in the false belief

that they are providing for more labor.

CHAPTER XVII.

Administration (_Continued_).

ACCOUNTS AND TECHNICAL DATA AND REPORTS; WORKING COSTS; DIVISION

OF EXPENDITURE; INHERENT LIMITATIONS IN ACCURACY OF WORKING COSTS;

WORKING COST SHEETS. GENERAL TECHNICAL DATA; LABOR, SUPPLIES, POWER,

SURVEYS, SAMPLING, AND ASSAYING.

First and foremost, mine accounts are for guidance in the distribution

of expenditure and in the collection of revenue; secondly, they

are to determine the financial progress of the enterprise, its

profit or loss; and thirdly, they are to furnish statistical data to

assist the management in its interminable battle to reduce expenses

and increase revenue, and to enable the owner to determine the

efficiency of his administrators. Bookkeeping _per se_ is no part

of this discussion. The fundamental purpose of that art is to cover

the first two objects, and, as such, does not differ from its

application to other commercial concerns.

In addition to these accounting matters there is a further type

of administrative report of equal importance--that is the periodic

statements as to the physical condition of the property, the results

of exploration in the mine, and the condition of the equipment.

ACCOUNTS.

The special features of mine accounting reports which are a development

to meet the needs of this particular business are the determination

of working costs, and the final presentation of these data in a

form available for comparative purposes.

The subject may be discussed under:--

1. Classes of mine expenditure.

2. Working costs.

3. The dissection of expenditures departmentally.

4. Inherent limitations in the accuracy of working costs.

5. Working cost sheets.

In a wide view, mine expenditures fall into three classes, which

maybe termed the "fixed charges," "proportional charges," and "suspense

charges" or "capital expenditure." "Fixed charges" are those which,

like pumping and superintendence, depend upon time rather than

tonnage and material handled. They are expenditures that would not

decrease relatively to output. "Proportional charges" are those

which, like ore-breaking, stoping, supporting stopes, and tramming,

are a direct coefficient of the ore extracted. "Suspense charges" are

those which are an indirect factor of the cost of the ore produced,

such as equipment and development. These expenditures are preliminary

to output, and they thus represent a storage of expense to be charged

off when the ore is won. This outlay is often called "capital

expenditure." Such a term, though in common use, is not strictly

correct, for the capital value vanishes when the ore is extracted,

but in conformity with current usage the term "capital expenditure"

will be adopted.

Except for the purpose of special inquiry, such as outlined under

the chapter on "Ratio of Output," "fixed charges" are not customarily

a special division in accounts. In a general way, such expenditures,

combined with the "proportional charges," are called "revenue

expenditure," as distinguished from the capital, or "suspense,"

expenditures. In other words, "revenue" expenditures are those

involved in the daily turnover of the business and resulting in

immediate returns. The inherent difference in character of revenue

and capital expenditures is responsible for most of the difficulties

in the determination of working costs, and most of the discussion

on the subject.

WORKING COSTS.--"Working costs" are a division of expenditure for

some unit,--the foot of opening, ton of ore, a pound of metal,

cubic yard or fathom of material excavated, or some other measure.

The costs per unit are usually deduced for each month and each

year. They are generally determined for each of the different

departments of the mine or special works separately. Further, the

various sorts of expenditure in these departments are likewise

segregated.

In metal mining the ton is the universal unit of distribution for

administrative purpose, although the pound of metal is often used

to indicate final financial results. The object of determination of

"working costs" is fundamentally for comparative purposes. Together

with other technical data, they are the nerves of the administration,

for by comparison of detailed and aggregate results with other mines

and internally in the same mine, over various periods and between

different works, a most valuable check on efficiency is possible.

Further, there is one collateral value in all statistical data not

to be overlooked, which is that the knowledge of its existence

induces in the subordinate staff both solicitude and emulation.

The fact must not be lost sight of, however, that the wide variations

in physical and economic environment are so likely to vitiate

conclusions from comparisons of statistics from two mines or from

two detailed works on the same mine, or even from two different

months on the same work, that the greatest care and discrimination

are demanded in their application. Moreover, the inherent difficulties

in segregating and dividing the accounts which underlie such data,

render it most desirable to offer some warning regarding the limits

to which segregation and division may be carried to advantage.

As working costs are primarily for comparisons, in order that they

may have value for this purpose they must include only such items

of expenditure as will regularly recur. If this limitation were more

generally recognized, a good deal of dispute and polemics on the

subject might be saved. For this reason it is quite impossible that

all the expenditure on the mine should be charged into working costs,

particularly some items that arise through "capital expenditure."

THE DISSECTION OF EXPENDITURES DEPARTMENTALLY.--The final division

in the dissection of the mine expenditure is in the main:--

/(1) General Expenses. / Ore-breaking. \

| | Supporting Stopes. | Various

_Revenue._< (2) Ore Extraction. < Trucking Ore. | expenditures

| \ Hoisting. | for labor,

\(3) Pumping. | supplies, power,

/ Shaft-sinking. | repairs, etc.,

| Station-cutting. > worked out per

| Crosscutting. | ton or foot

/(4) Development. < Driving. | advanced

_Capital | | Rising. | over each

or < | Winzes. | department.

Suspense._ | \ Diamond Drilling. /

| (5) Construction and \ Various Works.

\ Equipment. /

The detailed dissection of expenditures in these various departments

with view to determine amount of various sorts of expenditure over

the department, or over some special work in that department, is

full of unsolvable complications. The allocation of the direct

expenditure of labor and supplies applied to the above divisions or

special departments in them, is easily accomplished, but beyond this

point two sorts of difficulties immediately arise and offer infinite

field for opinion and method. The first of these difficulties arises

from supplementary departments on the mine, such as "power," "repairs

and maintenance," "sampling and assaying." These departments must

be "spread" over the divisions outlined above, for such charges

are in part or whole a portion of the expense of these divisions.

Further, all of these "spread" departments are applied to surface

as well as to underground works, and must be divided not only over

the above departments but also over the surface departments,--not

under discussion here. The common method is to distribute "power" on

a basis of an approximation of the amount used in each department;

to distribute "repairs and maintenance," either on a basis of shop

returns, or a distribution over all departments on the basis of

the labor employed in those departments, on the theory that such

repairs arise in this proportion; to distribute sampling and assaying

over the actual points to which they relate at the average cost

per sample or assay.

"General expenses," that is, superintendence, etc., are often not

included in the final departments as above, but are sometimes "spread"

in an attempt to charge a proportion of superintendence to each

particular work. As, however, such "spreading" must take place

on the basis of the relative expenditure in each department, the

result is of little value, for such a basis does not truly represent

the proportion of general superintendence, etc., devoted to each

department. If they are distributed over all departments, capital

as well as revenue, on the basis of total expenditure, they inflate

the "capital expenditure" departments against a day of reckoning when

these charges come to be distributed over working costs. Although it

may be contended that the capital departments also require supervision,

such a practice is a favorite device for showing apparently low

working costs in the revenue departments. The most courageous way

is not to distribute general expenses at all, but to charge them

separately and directly to revenue accounts and thus wholly into

working costs.

The second problem is to reduce the "suspense" or capital charges

to a final cost per ton, and this is no simple matter. Development

expenditures bear a relation to the tonnage developed and not to

that extracted in any particular period. If it is desired to preserve

any value for comparative purposes in the mining costs, such outlay

must be charged out on the basis of the tonnage developed, and such

portion of the ore as is extracted must be written off at this

rate; otherwise one month may see double the amount of development

in progress which another records, and the underground costs would

be swelled or diminished thereby in a way to ruin their comparative

value from month to month. The ore developed cannot be satisfactorily

determined at short intervals, but it can be known at least annually,

and a price may be deduced as to its cost per ton. In many mines

a figure is arrived at by estimating ore-reserves at the end of

the year, and this figure is used during the succeeding year as a

"redemption of development" and as such charged to working costs,

and thus into revenue account in proportion to the tonnage extracted.

This matter is further elaborated in some mines, in that winzes

and rises are written off at one rate, levels and crosscuts at

another, and shafts at one still lower, on the theory that they

lost their usefulness in this progression as the ore is extracted.

This course, however, is a refinement hardly warranted.

Plant and equipment constitute another "suspense" account even

harder to charge up logically to tonnage costs, for it is in many

items dependent upon the life of the mine, which is an unknown

factor. Most managers debit repairs and maintenance directly to

the revenue account and leave the reduction of the construction

outlay to an annual depreciation on the final balance sheet, on the

theory that the plant is maintained out of costs to its original

value. This subject will be discussed further on.

INHERENT LIMITATIONS IN ACCURACY OF WORKING COSTS.--There are three

types of such limitations which arise in the determination of costs

and render too detailed dissection of such costs hopeless of accuracy

and of little value for comparative purposes. They are, first, the

difficulty of determining all of even direct expenditure on any

particular crosscut, stope, haulage, etc.; second, the leveling effect

of distributing the "spread" expenditures, such as power, repairs,

etc.; and third, the difficulties arising out of the borderland

of various departments.

Of the first of these limitations the instance may be cited that

foremen and timekeepers can indicate very closely the destination of

labor expense, and also that of some of the large items of supply,

such as timber and explosives, but the distribution of minor supplies,

such as candles, drills, picks, and shovels, is impossible of accurate

knowledge without an expense wholly unwarranted by the information

gained. To determine at a particular crosscut the exact amount of

steel, and of tools consumed, and the cost of sharpening them,

would entail their separate and special delivery to the same place

of attack and a final weighing-up to learn the consumption.

Of the second sort of limitations, the effect of "spread" expenditure,

the instance may be given that the repairs and maintenance are done by

many men at work on timbers, tracks, machinery, etc. It is hopeless

to try and tell how much of their work should be charged specifically

to detailed points. In the distribution of power may be taken the

instance of air-drills. Although the work upon which the drill is

employed can be known, the power required for compression usually

comes from a common power-plant, so that the portion of power debited

to the air compressor is an approximation. The assumption of an

equal consumption of air by all drills is a further approximation.

In practice, therefore, many expenses are distributed on the theory

that they arise in proportion to the labor employed, or the machines

used in the various departments. The net result is to level down

expensive points and level up inexpensive ones.

The third sort of limitation of accounting difficulty referred

to, arises in determining into which department are actually to be

allocated the charges which lie in the borderland between various

primary classes of expenditure. For instance, in ore won from

development,--in some months three times as much development may

be in ore as in other months. If the total expense of development

work which yields ore be charged to stoping account, and if cost

be worked out on the total tonnage of ore hoisted, then the stoping

cost deduced will be erratic, and the true figures will be obscured.

On the other hand, if all development is charged to 'capital account'

and the stoping cost worked out on all ore hoisted, it will include

a fluctuating amount of ore not actually paid for by the revenue

departments or charged into costs. This fluctuation either way

vitiates the whole comparative value of the stoping costs. In the

following system a compromise is reached by crediting "development"

with an amount representing the ore won from development at the

average cost of stoping, and by charging this amount into "stoping."

A number of such questions arise where the proper division is simply

a matter of opinion.

The result of all these limitations is that a point in detail is

quickly reached where no further dissection of expenditure is justified,

since it becomes merely an approximation. The writer's own impression

is that without an unwarrantable number of accountants, no manager

can tell with any accuracy the cost of any particular stope, or

of any particular development heading. Therefore, aside from some

large items, such detailed statistics, if given, are to be taken

with great reserve.

WORKING COST SHEETS.--There are an infinite number of forms of

working cost sheets, practically every manager having a system of

his own. To be of greatest value, such sheets should show on their

face the method by which the "spread" departments are handled, and

how revenue and suspense departments are segregated. When too much

detail is presented, it is but a waste of accounting and consequent

expense. Where to draw the line in this regard is, however, a matter

of great difficulty. No cost sheet is entirely satisfactory. The

appended sheet is in use at a number of mines. It is no more perfect

than many others. It will be noticed that the effect of this system

is to throw the general expenses into the revenue expenditures,

and as little as possible into the "suspense" account.

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.

Administration.

Administrative reports.

Air-compression.

-drills.

Alteration, secondary.

Alternative shafts to inclined deposit.

Amortization of capital and interest.

Animals for underground transport.

Annual demand for base metals.

report.

Artificial pillars.

Assay foot.

inch.

of samples.

plans.

Assaying.

A value of mine.

Averages, calculation.

Bailing.

Balance sheet.

Basic price.

value of mine.

Benches.

Bend in combined shafts.

Bins.

Blocked-out ore.

Blocks.

Bonanzas, origin.

Bonus systems, of work.

Breaking ore.

Broken Hill, levels.

ore-pillars.

Bumping-trough.

Cable-ways.

Cages.

Calculation of averages.

of quantities of ore.

Capital expenditure.

Caving systems.

Churn-drills.

Chutes, loading, in vertical shaft.

Classification of ore in sight.

Combined shaft.

stopes.

Commercial value of projects, determination.

Compartments for shaft.

Compressed-air locomotives.

-air pumps.

_vs_. electricity for drills.

Content, average metal, determining.

metal, differences.

Contract work.

Copper, annual demand.

deposits.

ores, enrichment.

Cost of entry into mine.

of equipment.

production.

per foot of sinking.

working.

Cribs.

Crosscuts.

Cross-section of inclined deposit which must be attacked in depth.

showing auxiliary vertical outlet.

Crouch, J. J.

Cubic feet per ton of ore.

foot contents of block.

Deep-level mines.

Demand for metals.

Departmental dissection of expenditures.

Deposits, _in situ_.

ore, classes.

regularity.

size.

structure.

Depth of exhaustion.

Determination of average metal contents of ore.

Development in early prospecting stage.

in neighboring mines.

of mines.

Diamond-drilling.

Diluting narrow samples to a stoping width.

Dip.

Direct-acting steam-pumps.

Distribution of values.

Dividend, annual, present value.

Dommeiler.

Down holes.

Drainage.

comparison of different systems.

systems.

Drifts.

Drill, requirements.

Drilling.

Drives.

Dry walling with timber caps.

Efficiency, factors of.

of mass.

Electrical haulage.

pumps.

Electricity for drills.

Engine, size for winding appliances.

Engineer, mining, as executive.

Engineering projects, phases of.

Enrichment.

at cross-veins.

Entry, to mine.

to vertical or horizontal deposits.

Equipment, cost.

improvements.

mechanical.

Erosion.

Error, percentage in estimates from sampling.

Escape.

Examination of mining property.

Excavation, supporting.

Exhaustion, depth.

Expenditures, departmental dissection.

mine.

Extension in depth.

Factor of safety in calculating averages of samples.

Filling.

system combined with square-setting.

with broken ore subsequently withdrawn.

waste.

Fissure veins.

Fissuring.

depth.

Fixed charges.

Flat-back stope.

Flexibility in drainage system.

Floors.

Folding.

Foot-drilled system of contract work.

-hole system of contract work.

of advance system of contract work.

value.

Fraud, precautions against in sampling.

General expenses.

Gold deposits.

deposits, alteration.

enrichment.

Hammer type of drill.

Hand-drilling.

-trucking.

Haulage, electrical.

equipment in shaft.

mechanical.

Hole system of contract work.

Horizons of ore-deposits.

Horizontal deposits, entry.

stope.

filled with waste.

Hydraulic pumps.

Impregnation deposits.

Inch, assay.

Inclined deposits to be worked from outcrop or near it.

deposits which must be attacked in depth.

shaft.

Inclines.

capacity.

Infiltration type of deposits.

Intelligence as factor of skill.

Interest calculations in mine valuation.

Intervals, level.

Inwood's tables.

Iron hat.

leaching.

Ivanhoe mine, West Australia.

Kibble.

Labor, general technical data.

handling.

unions.

Lateral underground transport.

Le Roi mine.

Lead, annual demand.

deposits.

enriching.

prices, 1884-1908.

-zinc ores, enrichment.

Lenses.

Levels.

intervals.

of Broken Hill.

protection.

Life, in sight.

of mine.

Locomotives, compressed-air.

Lode mines, valuation.

Lodes.

Long-wall stope.

Machine-drill, performance.

drilling.

_vs_. hand-drilling.

Management, mine.

Matte.

Mechanical efficiency of drainage machinery.

equipment.

Men for underground transport.

Metal content, determining.

contents, differences.

demand for.

mine, value.

price.

Mines compared to other commercial enterprises.

equipment.

expenditures.

Mines--_continued._

life of.

metal, value of.

of moderate depths.

to be worked to great depths.

valuation.

Mining engineering profession.

Mt. Cenis tunnel.

Morgan gold mine.

Normal price.

Obligations of engineering profession.

Openings, position in relation to secondary alteration.

Ore, average width in block.

blocked-out.

-bodies.

shapes.

-breaking, methods.

calculation of quantities of.

-chutes in shrinkage-stoping.

-deposits, classes.

determination of average metal contents.

developed.

developing.

expectant.

in sight.

sight, classification.

-pillars.

support in narrow stopes.

-shoots.

weight of a cubic foot.

width for one sample.

Origin of deposit.

Outcrop mines.

Output, factors limiting.

giving least production cost.

maximum, determination.

Overhand stapes.

Overproduction of base metal.

Oxidation.

Patchwork plant, mechanical inefficiency of.

Pay areas, formation.

Pillars, artificial.

Positive ore.

value of metal mine.

Possible ore.

Power conditions.

general technical data.

sources.

transmission.

Preliminary inspection.

Previous yield.

Price of metals.

Probable ore.

Producing stage of mine.

Production, cost.

Profit and loss account.

factors determining.

in sight.

Proportional charges.

Prospecting stage of mine.

Prospective ore.

value.

Protection of levels.

Proved ore.

Pumping systems.

Pumps, compressed-air.

electrical.

hydraulic.

rod-driven.

Ratio of output to mine.

Recoverable percentage of gross assay value.

Recovery of ore.

Rectangular shaft.

Redemption of capital and interest.

Reduction of output.

Regularity of deposit.

Reliability of drainage system.

Replacement.

Reports.

administrative.

Resuing.

Revenue account.

Rill-cut overhand stope.

method of incline cuts.

-stopes.

filled with waste.

-stoping.

Rises.

Risk in mining investments.

in valuation of mines.

Roadways, protecting in shrinkage-stoping.

Rod-driven pumps.

Rotary steam-pumps.

Round vertical shafts.

Runs of value.

test-treatment.

Safety, factor of, in calculating averages of samples.

Sample, assay of.

average value.

narrow, diluting to a stoping width.

sections.

taking, physical details.

manner of taking.

Sampling.

accuracy.

percentage of error in estimates from.

precautions against fraud.

Saving of fixed charges.

Secondary alteration.

enrichment.

Security of investment.

Self-dumping skip.

Sets.

Shafts.

arrangement for very deep inclined shafts.

compartments.

different depths.

haulage.

location.

number.

output capacity.

shape.

size.

Shrinkage-stope.

-stoping.

advantages.

disadvantages.

when applicable.

Silver deposits.

deposits, enrichment.

prices.

Sinking, speed.

Size of deposit.

Skill, effect on production cost.

Skips.

balanced.

haulage in vertical shaft.

Sollars.

Solubility of minerals.

Specific volume of ores.

Speculative values of metal mine.

value of mine.

Spelter, annual demand.

Square-set.

-set timbering.

Stations.

arrangement for skip haulage in vertical shaft.

Steam-pumps, direct.

Steepening winzes and ore passes.

Stope filled with broken ore.

minimum width.

Stoping.

contract systems.

Storing metal.

Structural character of deposit.

Structure of deposit.

Stull and waste pillars.

support with waste reënforcement.

-supported stope.

Stulls.

wood.

Subheading.

Sublevel caving system.

Subsidiary development.

Superficial enrichment.

Supplies, general technical data.

Support by pillars of ore.

Supporting excavation.

Surveys.

Suspense charges.

Test parcels.

sections.

-treatment runs.

Timber, cost.

Timbered shaft design.

Timbering.

Tin, annual demand.

deposits.

ore, migration and enrichment.

Tools.

Top slicing.

Tracks.

Transport in stopes.

Tunnel entry.

feet paid for in 10 years.

size.

Underhand stopes.

Uppers.

Valuation, mine.

of lode mines.

mines, risk in.

mines with little or no ore in sight.

on second-hand data.

Value, average, of samples.

discrepancy between estimated and actual.

distribution.

of extension in depth, estimating.

positive, of metal mine.

present, of an annual dividend.

of $1 or £1, payable in -- years.

runs of.

speculative, of metal mine.

Valuing ore in course of breaking.

Ventilation.

Vertical deposits, entry.

interval between levels.

shafts.

capacity.

Volume, specific, of ores.

Waste-filled stope.

Water-power.

Weight per cubic foot of ore.

Weindel, Caspar.

Whiting hoist.

Width of ore for one sample.

Winding appliances.

Winzes.

in shrinkage-stoping.

to be used for filling.

Working cost.

inherent limitations in accuracy of.

sheets.

Workshops.

Yield, previous.

Years of life required to yield --% interest.

Zinc deposits.

leaching.

End of Project Gutenberg's Principles of Mining, by Herbert C. Hoover

Principles of Mining: Valuation, Organization and Administration · 第 22 / 22 章

BAILING.--Bailing deserves to be mentioned among drainage methods,