THE
QUARTZ OPERATOR'S
HAND-BOO K.
BY
P. M. RANDALL.
REVISED AND ENLARGED:EDITION.
NEW YORK:
D. VAN NOSTRAND, PUBLISHER,
23 MURRAY ST. AND 27 WARREN ST.




Entered according to Act of Congress, in the year 1871, by
D. VAN NOSTRAND,
In the Office of the Librarian of Congress, at Washington.
DENNIS BRO'S & THORNE,
STEREOTYPERS, AUBURN:, N. Y.




CONTENTS.
ArPPLIE D  MECHANICS.....................................    150
Thin  Cylinders,.......................................   150
Thick  Hollow   Cylinders,...................................                                       151
Relative Grinding Capacity of differently formed Grinding
Plates..................................................   152
Friction.....................................................  153
Water-Pipes,................................................   153
Velocity  of  Streams,...................................   155
Water-Power,.........................................                                            156
Water-Wheels,.......................... 158
Steam Power................................................ 100
ASSAY......................................................   99
Mechanical Assays,                       9...9............   99
Dry  Way  of Assay,.............................   99
Humid Way of Assay,....................................  103
Assay or Analysis of Iron Ores containing Manganese,.......  105
Assay or Analysis of Ores containing Gold, Silver, Copper,
Lead, Iron, and Sulphur.................................  106
BEHIVIOR OF SOLUTIONS OF METALLIC OXIDES WITH REAGENTS,.  87
BLOW-PIPE.............................................            96
EXAMINATION   OF  MINERALS....................................                   82
GOLD......................................................   114
Treatment of Ore containing Gold:
-By Smelting..1.................................                                                    114
-By Amalgamation,......................    115
-By Chlorination,...........................................    118
MILL-STAMP...................................................                  66
"-SILVER........1................... 7
"   -GOLD...................................................             76
MINERAL VEINS...............................9...........                                                    9
Species of,..................................................  11
Formation of,...............................................   14
Exploration  of..............................................  18
Exploitation of,.....................................   20




4                                            CONTENTS.
MINES-VENTILATION OF...................................  30
QUARTZ  MAC INIERY............................................                       38
Rock  Breakers,............................................    38
Batteries,..................................................                                      40
Mortars,....................................................    40
Tappets,....................................................    43
Cams,.......................................................                              44
Cam-Shaft,.....................................   46
Stamps.....................................................                                      46
Dies........................................................                                     48
Screens,....................................................                                       48
Guides,...............................................    49
Grinders and  Amalgamators,......................                49
Wheeler and Randall's Excelsior Grinder and Amalgamator,..  50
Separators,..................................................                            53
Wheeler and Randall's Conoidal Separator...................   54
Concentrators..............................................                         56
Wheeler and Randall's Eureka Concentrator...........                                               57
The Wheeler and Randall Tabular Concentrator and Amalgamator,........................................    58
Retorts......................................................                                     61
Gold  Retorts,...........2...................,.......                                           62
Silver Retorts,..., -.                     - -   -.........................                    63
Crucibles..................................................                    64
Ingot Molds,............................................    65
REDUCTION AND CONCENTRATION OF ORES-DRY WAY..........  79
ROSTIN.......................................................  109
Heaps,.....................................................                                      109
Furnaces,...................................................   109
SMELTING............. 112
SME3LTING~;........................................                            112
SILVER............................ 120
Ores of Silver,.............................. 120
Treatment of Silver Ores:
-By  Smelting,............................................   123
-B y -Solution,.........................................   131
-By Amalgamation,,,,.-........................  135
Extraction  of Silver from    coarse Copper,....................    139
Extraction of Silver from'Copper Matte,.................... 140
Sodium    Amalgam,-..................................   145
Purification of Mercury,...................... 146
Quicksilvering of Copper-Plate,...................                                               147
Cupellation  of Gold and  Silver,.............................   147
Refining  of Gold and  Silver,.................................   148
TABLES.,..............................................  167




PREFACE.
IN the authorship of the first edition of the "Quartz
Operator's Hand-Book," published in San Francisco,
A. D. 1865, the undersigned, through courtesy, associated with his own, the name of Mr. Zenas Wheeler, his
partner at the time in mining engineering, design and
structure of mining machinery, and the practical treatment of ores.  But in consideration of the decease of
Mr. Wheeler, and the extent of the changes made in the
revision of the "Hand-Book," the writer has not felt at
liberty to further connect with its authorship the name
of his lamented friend, of whom, as a just tribute to
his memory it must be said, that no one did more toward
perfecting the quartz-mining machinery in most general
use on the Pacific coast; corroborative of the truth of
which, reference need only be had to his inventions of
the High Mortar, Gib-Tappet, Self-Regulating Quicksilver Discharge Apparatus, Continuous Working Concentrator and Grinder, and Amalgamator; also, to his
associate inventions of the Tractory Grinders and Amalgamators, and Conoidal Separator. As the conclusions
of one so eminently qualified as Mr. Wheeler to judge of




13                   PREFACE.
the relative merits of quartz-mining machinery are of
the highest practical importance, it seems due to all
concerned, to state that the Straight Battery, Excelsior
Grinder and Amalgamator, and Conoidal Separator, described in this work, are the only machines which, of
their respective kinds, had his entire approval.
The principal changes referred to above consist in
striking out of the "Hand-Book" the more abstruse
matter, and in adding that which is regarded at this
time more directly applicable to the wants of the mining
public.
The object of the author,. in the preparation of the
work in hand, has been to present a clear and comprehensive exposition of mineral veins, and the means and
modes chiefly employed for the mining and working of
their ores-more especially those containing gold and
silver.
To secure this end, the standard authors, the most
skillful miners, mechanics, millmen and mill-wrights have
been freely and closely consulted.
The consequent deductions have been carefully compared with the writer's own experience for many years
in working mineral veins and in treating their ores and
metals. The best authenticated results therefrom have
been adopted and set down with a view to systematic
arrangement, conciseness and perspicuity. For the articles on the " Examination of Minerals," and the " Behavior of Solutions of Metallic Oxides with Re-Agents,"
due acknowledgments of indebtedness are here made




PREFACE.                    7
respectively to Dr. Lamborne's "Metallurgy of Silver
and Lead," and to " Noad's Chemical Analysis."
To what extent the author has succeeded in his object,
is submitted with no little diffidence to the decision of
the public.
P. M. RANDALL.
Nxw YORKE, January, 1871.








QUARTZ OPELATOR'S HAND-BOOK.
-MINERAL VEINS.
MINERAL VEINs are masses of rock, usually of the
tabular form intersecting other rocks.
One portion of a mineral vein is called," gangue
matrix" or vein - stone, consisting of quartz, calcite,
barytes, fluor, etc.; the other portion-ore, consisting of
a metal compounded with some other substance as
oxygen, sulphur or carbon.
The term "ore" is also employed, sometimes to signify
a native metal, and sometimes the entire material of a
vein.
Mineral Veins occur both in stratified and unstratified
rocks, also between the two. Those in the stratified generally cross the strata, but sometimes run parallel with
the layers. When a vein is not vertical, the adjacent
rocks on the upper side are termed its "hanging wall,"
and those on the lower its " foot-wall." Usually, however,
between a vein and one of its walls proper is a clayey
seam called " selvage," or, more familiarly, " gouge."
A layer of half decomposed rock adjoining a vein is




10         QUARTZ OPER ATOR'S HAND-BOOK.
called "flucan."  The "flucan" generally accompanies
cross courses and slides.
Veins differ greatly as to thickness —some averaging a
few inches, and others several feet. They seldom have
for any considerable distance their opposite walls quite
parallel, but alternately swell and contract, and sometimes pinzch out entirely.
The spaces thus wanting in ore are termed "faults."
VWhen these occur the walls sometimes come nearly or
quite together, and sometimes are kept apart by the
" gouge."
The gouge is greatly relied on by the miner to lead
him to the vein when it has been displaced. The termi
"fault," however, is used in a wider sense, to signify any
displacement or interruption in a vein's continuity.
When veins are very thick they usually contain much
earthy matter and fragments of rock mingled with the
ore. In veins of this description, also in the more swollen
portions of irregular veins, are occasionally found imbedded large blocks of detached wall-rock and bowlder, like
masses of barren quartz rock, which respectively are
known to miners by the names of " horses," " riders " and
"white horses."
The principal mineral veins extend downward to unknown depths, and horizontally, in many instances a distance of many miles.
As a general rule, a proper vein increases in thickness
with its descent into the earth's crust, thus presenting
the form of a wedge having its edge upward.




MINERAL VEINS.                11
Those portions of a vein which rise above the surface
of the earth are called "croppings," " outcrops," and
" blossoms."
The inclination with which a vein penetrates the earth
is termed its " dip," and is measured by the angle which
it makes with the horizon. The ", dip " varies in different
veins from an angle of a few degrees to that of a right
angle. The direction in which a vein runs horizontally
is called its "bearing" or "strike," and for the most
part is parallel with the mountain range in which it is
found.
No general law, however, seems to obtain as to the direction of veins in different mining districts. Thus, when
carrying the same metal in kind, they run in some districts north and south, and in others east and west. In
the same district different veins containing the same metal
in kind usually run parallel, but when containing each
a different metal, they fiequently run in divers directions.
In Cornwall, England, for example, the tin and copper
veins run east and west, while the lead veins run north
and south.
SPECIES OF MINERAL VEINS.
Mineral veins present a variety of forms, and hence in
some localities are distinguished into species, of which
the principal are the Rake, Pipe, Flat or Dilated, Interlaced and Accumulated.




12         QUARTZ OPERATOR'S HAND-BOOK.
1st. The Rake Vein is of unknown depths, and often
many miles in length.  Commencing at the surface of
the earth it cuts the strata downward, nearly perpendicular to their plane of stratification.  For the most part
it evidently also intersects the unstratified rocks, and
probably passes entirely through the earth's crust to the
central mass. The "dip" in different rake veins varies
from an inclination of a few degrees to a perpendicular.
This class embraces the large proportion of mineral
veins proper and is the one most valued by operators in
mines.
2d. The Pipe Vein runs forward end-wise in a hole in
the earth's crust. It resembles an irregular shaft filled
with mineral substance, rather than a tabular mass of
ore. It generally does not traverse the strata, but lies
between the layers. Its "dips' is usually less than that
of the rake vein. Veins of this class vary greatly in size,
some being only a few feet in diameter and others several
yards.
3d. The Flat or Dilated Vein is a flattened mass of ore
between the strata or beds of other rocks. Its relations
to the adjacent formations are much the same as those of
a stratum of coal to its inclosures. Its position, also like
that of a stratum of coal, is usually horizontal or not
much inclined. But when breaks or other interruptions
occur in a dilated vein, it differs from a coal seam by
greatly varying in thickness within the limits of a few
feet. At these breaks or slips often occur the richer deposits of metallic substances.  Similar to the rake vein,




MINERAL VEINS.                 13
the dilated in its course is subject to contractions and
expansions.
4th. The Interlaced Vein is composed of numerous small
veins running together in the form of irregular net-work.
Different members of the same vein, or system of veins,
though running in the same general direction, often vary
considerably from each other in " dip."
Interlaced veins are chiefly enclosed by rocks of prihnitive formation, and more frequently bear the ores of tin
than those of any other metal.
5th. The Accumulated Vein is a large, irregular mass
of ore, apparently filling cavernous spaces in the earth's
crust, and showing no indications of being connected to
other mineral deposits. From its entire want of any
order, its deposition would seem to have been accidental,
rather than the result of any well-recognized system.
Veins of this class are sometimes found in stratified
rocks, between the strata, and sometimes enveloped in
unstratified rocks.
REMARKS.-Besides the several classes of veins described, small masses of rock, termed " nests," "concretions," "nodules," bearing metallic substances, occur in
the middle of strata, or beds of other rock. The ores
of iron are frequently found in these forms.
False veins also occur in addition to the veins enumerated. These, as to their "walls" and "dip," resemble
proper veins; but being composed of sand, clay and
other alluvial substances, are readily distinguished from
the true crystalline and mineral veins.




14         QUARTZ OPERATOR'S HAND-BOOK.
FORMATION OF MINERAL VEINS.
The evidence is abundant that many mineral veins
were a long time in being formed after the fissures in
which they exist were produced.
-Banded veins, composed of crystalline matter in the
form of plates or " combs," divided from each other by
thin layers of clay, conclusively prove, not only that their
formation was slow, but that several re-openings of the
same fissures must have taken place at periods separated
by long intervals.
The fissures occupied by metallic veins seem to correspond to such rents as are produced from time to time
by the shock of an earthquake, and in a majority of cases
are evidently attributable to the same causes.
It is not improbable that some of these fissures were
produced by contraction, while the rocks through which
they run were passing from the plastic to the solid state.
The manner in which they were filled with ore and veinstone is still a subject of speculation among geologists.
The principal theories advanced to explain the phenomena of mineral veins are as follows:
Ist. That open fissures in the earth's crust were filled
with crystalline and metallic matter by aqueous infiltrations from above.
Thus, Werner supposed the substances of mineral veins
to have been precipitated from a " chaotic rnenstruum"
into fissures in the earth while it was in some nascent




MINERAL VEINS.                15
state. This theory at present has less advocates than
formerly.
However, that false veins were produced by infiltrations from the surface of the earth is evident from the
character of the deposits. It is also evident that some
of the material found deep in proper veins came from the
earth's surface or from the bed of the sea. Thus, for example, well-rounded pebbles of quartz and slate, pieces
of coral and marine fossil shells occur imbedded in several mineral veins at depths in some cases of over a
thousand feet below the surface. But these occurrences
without doubt were accidental, and had no connection
with the general system of repleting proper veins.
2d. That the contents of mineral veins, like those of
dikes, were formerly molten, and while in this state were
injected from below by mechanical force.
This view of the subject was proposed and maintained
by Dr. Hutton.
The explanation which it affords relative to the productions of some mineral veins is quite satisfactory.
But the evidence seems insufficient to warrant the inference that any considerable proportion of metallic veins
was produced in this manner.
3d. That the contents of some mineral veins were
deposited in fissures and cavities in the earth's crust by
the condensation of mineral vapors emanating from vast
subterranean fountains of intensely heated matter. This
theory, suggested by M. Neckar and Dr. Buckland,
appears to be an improvement upon that of Dr. IHutton's.




16        QUARTZ OPERATOR'S HAND-BOOK.
especially in its application to the formation of veins of
banded structure. The repletion of veins of this class,
owing to the great length of time requisite for its accomplishment, must be referred to chemical agencies rather
than to mechanical forces.
4th. That some mineral veins were produced in the
same manner as flint, or other concretions, by chemical
segregation from the inclosing rock prior to its solidification. It not unfrequently occurs that veins are found
passing by insensible gradations into the containing
rock. As this could take place only while both were in
the liquid state, it is evident that such veins are of cotemporaneous origin with the rock in which they are inclosed, and that they were in the process of more complete segegration at the time of their becoming solid.
This theory, proposed by Prof. Sedgwick, furnishes a
solution quite satisfactory as to the method by which
many of the flat or dilated veins, also the accumulated
veins and other masses of isolated mineral substances
were produced. And it is not improbable but that the
principle of chemical segregation was active in the production of some proper veins.
5th. That the formation of many mineral veins is due
to electro-chemical agencies.
The existence at present of electro-currents in some
Cornish veins, and the analogy between voltaic combinations and the arrangement of matter in mineral veins are
adduced by R. W. Fox and M. Becquerel in support of
this theory. Mr. Fox goes so far as to infer that the




MINERAL VEINS.                 17
richer. veins in metallic treasure are at right angles to the
earth's magnetism.
It is more than probable that electro-chemical influences are capable of transforming to considerable distances the substances composing mineral veins, even from
the solid rocks in which they are disseminated into fissures in the same, and of determining the arrangement
of the matter so transferred; but that electro-magnetic
currents effect richer metallic deposits in veins running
east and west than in those running north and south is
refuted by unequivocal evidence. True, the principal
and richer veins of Cornwall run east and west, but the
principal' veins of the entire Pacific Slope run nearly
north and south.
6th. That the matter of mineral veins originally disseminated in portions of the rocks adjoining rents and
cavities in the earth's crust, was introduced into these
openings by the process of infiltration. That the filtered
matter may have been derived by simple solution from
the inclosing rocks, or by decomposition of some of their
constituents; and when gathered into the receptacles
may have concreted unaltered in composition, or have
undergone various changes, induced by the mutual action
of its component parts. It has been inferred that, most
mineral veins were found in those fissures formerly occupied by thermal springs, for much of their material is
identical in character with that composing the walls of
those springs, or held in solution by their waters. Besides,
the vast depths to which both mineral veins and thermal




18        QUARTZ OPERATOR S HAND-BOK.
springs extend downward, and the similar relations which
they respectively bear to the great lines of upheaval
and dislocation of rocks, go far in support of this inference. That some mineral veins are of recent formation,
by infiltration, and that others are in process of format/on by hydro-thermal agencies, seems no longer problematic.
Geological researches on the Pacific coast disclose in
the vicinity of the village of Volcano, Amador county,
California, "distinctly marked quartz veins cutting
through the gravel, and evidently formed by the action
of water holding silica in solution;" also, that in Steamboat Valley, Nevada, semi-crystalline depositions of silica
and oxide of iron are being made on the walls of the
fissures of the boiling springs.
In this vicinity, another fissure of the same origin is
still nearer replete with mineral matter. This fissure, at
a few points along its extent, evolves steam and carbonic
acid, but no water. For the most part it is filled with
silicious concretions which contain the oxides of iron and
manganese, the sulphides of iron and copper, and metallic
gold.
EXPLORATION OF MINERAL VEINS.
Many rules have been made for the Exploration of
IMlineral Veins. But these, so numerous are the excep.
tions, are to be regarded hints rather than rules. Min.
eral veins occur in nearly every other formation of




MINERAL VEINS.                 19
rocks; and no unexceptional law seems to prevail as to
their comparative richness in the different formations.
Not unfrequently a mineral vein runs horizontally
through different strata of rock. Richer metallic depos.
its are sometimes found in the vein, inclosed in a stratum
of one formation of rock and sometimes in a stratum of
a different formation. Several authors are of opinion
that metallic veins are richer near the junction of strati.
flied and unstratified rocks.  In several quartz-mining
districts of California-to wit, in Mariposa-some of the
gold-bearing quartz veins are in granite, but the larger,
and so far as determined the richer veins, are in slate; in
Tuolumne the more valuable veins occur in granite, those
in the metamorphic slates are comparatively barren; in
Calaveras the quartz veins are found valuable both in
granite and limestone; in the Alta mining district the
"wall-rock" is serpentine, white talc accompanies the
richer deposits; in Amador the valuable veins are mostly
in slate. The celebrated Eureka, Oneida, Keystone and
Spring Hill veins are in slate. The former has been
worked nearly thirteen hundred feet in depth. The vein,
six feet thick at its "outcrop," has regularly increased
in thicknress and richness with the sinking.
The following suggestions are esteemed among the first
of importance for the Exploration of Miineral Veins:
1st. That mineral veins are more abundant in the older
crystalline rocks than in those of more recent formation.
2d. That they are more abundant in mountainous
and hilly regions than in the even land.




20         QUARTZ OPERATOR'S HAND-BOOK.
3d. That they are most productive near the junction
of stratified and unstratified rocks.
4th. That their locality is often indicated by the color
of the surface of the land. The color arises from the
decomposition of some of their constituents.
5th. That their locality is frequently determined by fragments of the vein scattered over the surface of the ground.
6th. That they are discoverable by their "outcrops."
The " outcrop" is the most obvious indication of a mineral vein. It is doubtless true that the great majority
of mineral or metallic veins discovered, is due to accident rather than to science, and that the discoveries so
made, to a great extent, have been by means of the " outcrop."  Sometimes the vein-stone and sometimes the
" walls " or country-rock, is the more obdurate. As the
case may be, the more yielding will have been worn away
by the action of water and other agencies, leaving the
other, so that the exploration of the vein is rendered quite
simple.
7th. That when the bearing is approximately determined, the vein may often be found by sinking one or
more shafts through the alluvial deposits into the underlying rock, and making a "trench" or " tunnel" at rightangles to the bearing of the vein.
EXPLOITATION OF MINERAL VEINS.
The.EExploitation of  ilineral Veins comprises the
various processes by which their ores are won from




MINERAL VEINS.                21
their natural position and brought to the surface of the
earth.
The Workings are Open and Subterraneous.
Open Workings apply to flat or dilated veins, and other
horizontal deposits situated near the surface. They are
usually arranged in terraces suited to the character and
disposition required of the material. Open workings are
sometimes quite extensively employed in the devleopment of mineral veins of considerable " dip." That is, the
vein, in the direction of its bearing, is uncovered for a
long distance. This practice, however, in most cases,
cannot be too severely reprehended. The natural roofing
of the vein should not be interfered with further than
absolute necessity requires.
Subterranean Workings are of two kinds, the Preparatory and those of.Extraction.
The Preparatory Workings consist in timbered or
otherwise properly secured shafts and tunnels, exposing
most effectually the ore sought to the attacks of the
miner; also in the means for ventilation, for the discharge
of water, and for the transportation of the detached
mineral out of the mine.
A shaft is a pit or narrow opening into a mine, and
may be vertical or inclined. It is to be regarded a tunnel when it forms with the horizon an angle less than
forty-five degrees (45~).
A winze is a small shaft connecting two levels, and
is employed for the purposes of ventilation or of exploration.




22.    QUARTZ OPERATOR'S HI-AND-BOOK.
The working-shaft, termed also the "hoisting-shaft,"
is employed for lowering into the mine, timbers, "spiling"
supplies and tools, also for raising ore, water, etc. The
miners, for the most part, pass in and out of the mine
through this shaft-either by ladder or in some form of
carriage, driven by steam or other motive power. The
working shaft is seldom less, transversely, than thirty by
forty inches.  Ordinarily it is much larger-of sufficient
size to admit the use of the double hoisting track, pumping machinery, and miner's ladder.
The air-shaft is emploved for the purposes of ventilation; also not unfrequently for filling -with dirt and
debris the chambers from which the ore has been extracted.  The working and air shafts are occasionally
several hundred feet apart-not often less than one hundred feet.
A sump is a pit usually at the bottom of the working
shaft, and is several feet deeper than the lowest of the
other workings. Its chief use is that of a reservoir into
which the waters of the mine are drained, whence by
machinery they are discharged at the surface.
A tennel is a narrow opening into a mine, and may be
horizontal or inclined.  It is to be regarded a shaft when
it forms with the horizon an angle greater than forty-five
degrees (45~). A tunnel excavated in a vein, and running the vein's course, in some localities is called a " gallery." A tunnel piercing or intersecting avein is termed
an "adit."  A tunnel connecting two shafts is called a
"drift," or " drift-way."  Tunnels are seldom less than




MINERAL VEINS.                23
two feet by three and one-third feet high. Quite a common size is three feet wide at the top, three and a half to
four feet wide at the bottom, and six feet high. The
size of the tunnel is very frequently determined by that
of the vein in which it is driven-the width of the
former being made equal to the thickness of the latter.
In considering further the problem of Preparatory
Workeings of Xineral Veins, let the rake vein be taken,
since, on account of its greater extent and regularity, it
is subject to more general and systematic operations
than any of the other forms. Regarding the occurrence
of the vein in even land, two shafts-working and air
shafts-should be sunk to nearly the same level, and united
at their greatest depth by a tunnel. The sump, the
mine containing much water, should be sunk before the
connecting tunnel is driven far-the shafts should be at
least a hundred feet apart, and, independent of the sump,
fully a hundred feet deep, and should, with the tunnel,
be well timbered or otherwise properly secured.
The Preparatory Workings may be almost indefinitely
extended by sinking the working and air shafts,, and
connecting them by tunnels at desired intervals; also
by sinking on the line of the vein other shafts and connecting them by tunnels.  The " sinkings " or " distances" between tunnels are usually from sixty to one hundred feet.
Regarding the occurrence of the vein in a mountain,
tunnels may often first be employed to advantage. The
vein and its inclosing mountain ridge being parallel and




24         QUARTZ OPERATOR'S HAND-BOOK.
unbroken, an "adit" at the lowest feasible level should
be made to intersect the vein, thence a gallery driven on
the vein to some desired point from which a shaft should
be raised or excavated to the surface. In case of a break
occurring, as by a cafion, the work frequently is greatly
facilitated, as thereby a tunnel may be commenced upon
the transverse or broken face of the vein and driven
directly on its course. This use of tunnels should rarely
be adopted, unless the elevation exceeds a hundred feet
in height.
As a general rule, shafts and tunnels should be wrought
in the "lode."
Veins, however, very thick and friable, having a dip
of less than forty-five degrees and being inclosed by unstable walls, furnish exceptions to this rule; such are to
be worked by vertical shafts rather than by shafts coinciding with the dip of the vein.
Workings of Extraction consist in detaching the veinmatter from its natural position and hoisting or bringing it to the surface of the earth.
There are two modes of attacking the vein, viz.: by.Direct or.Descending Steps, and by Reverse or Ascending
Steps.
In Fig. 1, taken in the plane of the " dip " and " strike"
of a mineral vein of the Rake species, let A B represent the working-shaft, C D and E F air-shafts, B D
and B F tunnels or galleries, G H and I K the limits of
the workings toward the surface, S the sump. Conceive the vein to be laid out into parallelopipeds or rec



FIG. 1.
E                                     A
MINERAL VEIN (EDXPLOITATION).
a~~~~~~~~~B
-0- -0 -0-o   0- -  0- -0  
Oi  0-o       -11
/  I  CZ
tfl   aO    o~~c
H              C l
W~~~~~~~~~~~~~
d —O  ~~~~~~~~~MNEJ
o~~~~~~~~~~~~~~~~~~\
IE~~~~~l~~~il dO~~~~~~
a   ol-~~~~~ Y                                                            ckr~~~~
e'~ ~      MMN
w    ~~~~~~~~~~~~~~~~~~O
MINEF.AL VEIN  (EXPLOITATION).)




26         QUARTZ OPERATOR'S HAND-BOOK.
tangular masses, and let these masses be represented by
al-as, etc., to nl -n; a'l-a, etc., to n- n5. One of
these masses is commonly fifteen or twenty feet long, six
or eight feet high, and as wide as the vein. Let aO, b~, c~,
do, e~, represent scaffolds or stages, 0,, o1, o1, floors firmly
timbered employed as tracks or ways for conveying the
ores to a common point of delivery, also for sustaining
the rubbish and securing the walls of the mine —and let
xi represent a guide-board or "shute."
By Direct or Descending Steps.-To extract the ore
by " descending steps," usually two miners, " leader" or
"lead-hand," and " striker," termed " a set," commencing
on stage a~, excavate in succession the parallelopipeds or
masses  al aa3, a4 and a5, deliver them into the shaft
E F, and construct the floor o,, 01, o,, shown at the bottom
of the excavated chambers a' -a5. In like manner a
second set,.commencing on stage b~, excavate and dispose
of the masses bl, b2, b3, b4 and b5; and so on set after set
of miners are employed, and the several masses from a to
n are disposed of and the respective floors o,, o,, o,, constructed as required. The order observed is that each
lower set of miners succeeds the set next above by the
length of a parallelopiped, that is fifteen or twenty feet.
Thus when five sets have come to be employed, while the
upper set is engaged on the mass a5, the next lower set
is on b4, the next lower on c3, and so on to el.
The ore delivered into the shaft E F is conveyed by
the tunnel F B to the working-shaft A B, by which it is
raised to the surface. It may be remarked that the




MINERAL VEINS.                 27
shaft E F is sometimes employed as a hoisting-shaft,
also that the excavations are sometimes made without
the use of the floors o1, 01, o,; such workings, however,
are crude and reprehensible.
-By Reverse or Ascending Steps. —To extract the ore
by " ascending steps," a set of miners, commencing on a
temporary stage, excavate in succession the parallelopipeds a,, a,, a3, a4, etc., and firmly timber floor or roof as
shown by o0, 0,, 0,, the tunnel B D. In like manner a
second set excavate successively the masses b,, b,, b6, etc.;
and so on set above set of miners, from  a to n, are
employed.
The order observed is that each upper set of miners
succeed the set next below by a parallelopiped fifteen or
twenty feet in length. Thus when five sets have come
to be employed, while the lower set is engaged on the
mass a5, the next upper set is on b4, the next upper on c3,
and so on to e,. Temporary stages are chiefly used.
By this method of reversed steps, the ore, as detached,
falls by its own weight. It is sometimes allowed to fall
freely into the tunnel, but is usually retained in the mine,
resting upon the tunnel floor or roof, whence it is discharged as required into cars, conveyed to the shaft A B,
and thence hoisted to the surface.
It may be observed that the shaft C D, or more generally speaking the shaft from which the "stopings" or
excavations are carried on, is sometimes employed as a
hoisting-shaft. This resort, however, should only be in
extreme cases.




28 -       QUARTZ OPERATOR'S HAND-BOOK.
The walls of a mineral vein, especially if excavated
by ascending steps, can often be more effectually and
economically secured by filling the chambers with dirt
and debris, obtained at the surface of the earth, than by
any other means.
When the inclosures are very friable and unstable, the
process of filling should succeed immediately that of
extraction. The miner thereby is not only secure against
the crumbling and falling walls, but is brought directly
up to his work.
The filling material, for example, is thrown into the
air-shaft C D, falls upon the adjustable shute x, whence it
is conducted into the openings a, - a4, b6- b, c,- c2, etc.
The filling should be well tamped.
In considering the relative merits of the two modes of
working, it is to be remarked:
That the mode of " descending steps" affords the miner
less restraint in position, and greater freedom of action;
that it is better adapted to the sorting of ores in the vein;
and that it is, in case of the vein-stone being much decomposed, less subject to loss by the liberated minerals
or metals becoming mixed with the rubbish.
And on the other hand: That the mode by " ascending
steps" is more expeditious and cheaper, requiring less
expense in timbering, flooring and filling, and less labor
in excavating, since the ore, by its own weight, is more
readily disengaged from its natural position.
Again, as one of the chief objects in mining should be
to keep the mine in good order, both regarding the facil




MINERAL VEINS.                 29
ity in operations and safety to the workmen, the caution
cannot be too well heeded against breaking through the
surface, or weakening the natural roof of the vein. In
most cases the " limit of workings," G H, I K, depending on the nature of the ground and thickness of the
vein, should not approach the surface nearer than at a
distance of twenty feet. Pillars of vein-stone are sometimes left in the mine for its better protection. These
may be left, especially along the sides of the workingshaft, with the highest advantage.  They, together with
the upper portion of the vein, can readily be reclaimed,
whenever desired.
As a general rule, it seems proper to observe, that
on engaging in quartz mining, the first thing to be done
is to thoroughly "prospect" the vein or mines. To accomplish this, regarding the vein of the Rake species, a
shaft should be sunk on it not less than one hundred feet
deep, a tunnel driven as far on its course, and the ore
worked by a process near as possible to that proposed to
be adopted. If the results prove favorable the adventurer may proceed to erect his quartz machinery for
working on a large scale, with assurances of almost certain success. If the results are unfavorable he may congratulate himself that he has not fallen intothe too frequent error of building expensive mills on worthless
"6 lodes."




VEINTILATION OF MINES.
The Ventilating of Minies is the act of circulating
through any or all portions of their " workings" pure air,
and substituting it for foul air and other noxious substances, of which those of most common occurrence are
"cholke-damp" (carbonic acid) and "fire-damp" (carbur
retted hydrogen) each producing by inhalation almost
instant death. The former of specific gravity 1,529 occupies the lowest part of the mine's workings, and the
latter of specific gravity,555 the upper part. "Firedamp" is combustible, and a mixture of one volume of it
with ten volumes of air is highly explosive. It is the
burning of this gas, and the explosion of its mixture with
air, that occasion at times such fearful havoc of life and
property. The resulting carbonic acid is called "afterdamp," and is more fatal to miners than even the fire
and explosion.
Choke-damp and Fire-damp do not usually occur in
any considerable quantities in the same mine. They are
eslpecially abundant in deposits of coal, which, being
blroken, one or the other is often copiously evolved from
its immense store-house. Their occurrence in mineral or
metalliferous veins in some cases may' be referable, to
no little extent, to the decomposition of vein matter, but
for the most part is attributable rather to the respiration




VENTILATION OF MINES.             31
of the workmen, the combustion of candles and blasting
powder, and the decomposition of wood and filling.
On entering a mine in which the existence of " chokedamp" is suspected, the adventurer should carry, on the
end of a pole, a burning candle, thrust a few feet in
advance. If the candle emits a strong light he can safely
proceed-if a feeble light, his progress is attended with
peril-and if it ceases to burn he cannot too quickly
retrace his steps, for certain death awaits him.
The existence of " fire-damp" in a mine is indicated by
the behavior of the " top" and flame of a candle, which
should be well trimmed.
The " top," or haze-like cap of the flame, maintaining
a yellowish brown color, not exceeding a quarter or half
inch in length, denotes that the air is almost or quite free
from " fire-damp."  The " top" elongating and changing
to a bluish-gray color warns the miner of the presence of
this gas. The "top," as also the flame shooting up into a
sharp spire, the former changing its color from bluishgray to a clear blue, while minute, luminous points rise
rapidly up through the flame and top, indicate that the
place abounds in "fire-damp," just on the point of bursting into flame and explosion. The miner in this perilous
condtition, mindful that the least agitation may effect the
ignition of the gas, slowly lowers his candle to the floor,
and cautiously retreats or ventures to extinguish the
flame with his thumb and finger.
The means of the Ventilation of Mines are " natural"
and " artificial."




32         QUARTZ OPERATOIR'S HAND-BOOK.
Natural Means, The difference between the temperature of the mine and that of the external air, combined
with the difference between the levels of the openings at
the surface, also at the points of their connection below
ground, produce a circulation of air through the mine.
A mine having two shafts of different levels at the surface, and of the same level at their points of tunnel-connection at the bottom, in case the internal temperature
is greater than the external, a circulation will be established through the mine. The rarified air will rise and
pass off, as by a chimney, through the shaft of the more
elevated opening, while its place will be supplied with
flesh air flowing in through the shaft of less elevated
opening. But in case the external temperature is greater
than the internal, the direction of the current will be
reversed.
If the mine occurs in a level country, a high chimney,
reared over one of the shafts, is made to supply the lack
of a natural difference in elevation.
Experience, however, shows that a mine having two
shafts of the same level at the surface, and of different
levels at the points of their tunnel-connection below, a
current of air will flow quite uniformly down the deeper
shaft, along the tunnel, and up the shaft of less depth.
A long tunnel driven into the side of a mountain may
readily be ventilated, by dividing it into two unequal
parts by a horizontal partition, by connecting its upper
and smaller part at some distance from the entrance,
with a shaft raised to the surface, and by letting its




VENTILATION OF MINES.             33
lower part communicate with the entrance and with the
upper part at the other extremity of the tunnel. A current is produced as the air in the upper or smaller part
becomes sooner heated by the enclosing rock, and passes
off through the shaft, while the fresh air to supply its
place flows in at the entrance, and thence along the lower
part of the tunnel to its extremity.
A mine may be ventilated to a limited extent by the
application of the wind. The apparatus consists of a
turn-cup, having a funnel-mouth open to the windward,
and communicating with the mine through a pipe. The
wind, arrested by the machine, is conducted by the pipe
into the mine, and disposed of as required.
Artificial Means, In artificial means are involved the
principles of " propulsion and exhaustion."  In applying
the principle of "propulsion," large bellows, force-fans,
and sometimes force-pumps are employed. By these, the
air, through pipes or other conductors, is driven into the
mine to those parts where most needed, whence it is dispersed through the workings, and finally escapes at the
mouth of the opening. This principle is especially advantageous in that it readily admits the use of flexible pipe,
or hose, by which the air is conducted with facility into
recesses of most difficult access. Its application, however, is either on a small scale or only comparatively temporary. The principle of " exhaustion" is more generally
applied, and with far greater economy and effect than
that of "propulsion."' It is put in practice by " exhausters," "fires" and "furnaces."  These, communicating
2*




34         QUARTZ OPERATOR'S HAND-BOOK.
with the open air, are in some way connected with pipes,
or their equivalents, extending to the remotest parts of
the mine. As the machines are put in operation a circulation of air is produced through the mine, the current
extending from the " opening" to the.extremities of the
exhaust pipes, through which it then, fraught with impurities passes and escapes above ground.
Instead of ordinary pipes, there are sometimes substituted covered trenches duog in the wall-rock of the shaft
and along the bottom of the tunnel. The rock furnishes
three sides of an air conductor. The fourth is formed
of plank fitted in its place air-tight with cement, or clay.
Sometimes the shafts and tunnels entrie are converted,
as it were, into air-pipes. This is especially the case in
the more extensive works.
The "exhausters," so called, consist of various contrivances, for the most part in the form of "pumps" and
"fans," whose relative merits with one another and
among themselves it is not proposed to discuss. " Fires,"
for the purposes of exhaustion, are applied in different
ways-by being placed at the mouth of the " up-cast " or
chimney-like shaft, or at the bottom, or by being suspended in grates part way down the shaft.
"Furnaces," especially in large operations, are most in
use. The position of the furnace is in connection with
the " up-cast" shaft, whose office is to conduct away the
vapors, vitiated air and gases of the mine, as they are
put in motion and caused to rise by the exhaustive influences of the heat. The furnace is sometimes placed




VENTILATION OF MINES.            35
at the top and sometimes at the bottom of the shaft.
The plan of placing it at the bottom is preferable, since,
in comparison, the sides of the shaft becoming heated,
ventilation is continued longer, and is less liable to
derangement, in case of accident occuring to the furnace.
The "'up-cast" and "down-cast," in other words the
escape and supply air-shafts are, in effect, the one at
one end of a long tunnel, and the other at the other end.
Other than this they have no communication, though
frequently only separated by a partition wall. In connection with the furnace it is now proposed to illustrate
a system of ventilation which is applied with complete
success even in coal mines abounding in fire-damp or
other noxious substances.
Let the mine be developed by a system of rectangular
tunnels, represented one way by letters a, b, c, d, e, and
the transverse way by numbers 1, 2, 3, 4, 5, 6, 7, and by
two shafts termed the "up-cast " and " down-cast," sunk
at the junction of b and 4 tunnels. Let air-tight doors be
placed in the tunnels as follows:-in a between 5th and
6th; in b between 1st and 2d, 2d and 3d, 6th and 7th; in
c between 2d and 3d, 3d and 4th, 4th and 5th; in d between 2d and 3d, 3d and 4th, 4th and 5th; in e between
3d and 4th; in 2d between c and d; in 3d between a
and b; in 5th between b and c, d and e; in 6th between
b and c, c and d, d and e, and in 7th between c and d.
Let the "supply" opening in the " down-cast " shaft be
in 4th looking toward a; and let the escape openings in
the " up-cast " shaft be —one in b looking toward 3d and




36        QUARTZ OPERATOR S HAND-BOOK.
one in 4th looking toward c. On the furnace being
put in operation the fresh air descends the " down-cast"
shaft, issues through the supply opening, and passes down
tunnel 4th to the junction of 4th and a, where it divides
into two streams. One stream flows to the right along a
up 5th, along b down 6th, along a up 7th, along c to
the left up 5th, along d to the right up 7th, along e to
the left down 4th into the "up-cast," and effects its
escape. The other stream flows to the left along a to 2d,
then in two branches-one up 2d and along c to 1st, the
other along a and up 1st to c; the branches here uniting, the stream flows up 1st to d, then in two branches
-one along d and up 2d to e, the other up 1st and along
e to 2d;-the branches here uniting, the stream flows
along e down 3d and along b into the "up-cast," and
escapes by the chimney.
In case of "fire-damp" being very abundant in any
portion of the mine, it is conducted by the way of the
dumb:furnace, which communicates with the "up-cast"
shaft, out of reach of the flame. The draught of this furnace arises fiom the exhausted condition of theflue of
the active furnace.
Too much care, however, cannot be used to dilute with
fresh air this gas below the explosive pdint before suffering it to escape. Explosion does not occur when the
volume of air is less than six or more than fourteen times
the volume of the gas. "Fire-damp" should not be inhaled unless mixed with air of full thirty times its volume. In practice, the mixture becomes not less diluted




VENTILATION OF MINES.              37
before it is taken to the active furnace. The doors or
valves are double,'that is, placed at some distance apart,
so that by the alternate opening and shutting of them
the currents of air are not interfered with.
The " doors," as also furnaces of ample capacity being
properly arranged and managed, the ventilation of the
mine, in its every part, is brought completely under control. At the pleasure of the manager, vapors the most
pestilential, and gases the most poisonous and inflammable
are aerified to a degree of entire salubrity, or imprisoned
for the time being, or sent harmless away by themselves.
This system applies alike to coal and horizontal deposits,
or to mineral veins of any dip and extent,-in a word,
is capable of almost unlimited application.




QUTARTZ MACHINERY.
For the mechanical reduction and concentration of ores,
two kinds of quartz machinery, the wet and the dry, are
in use. The application of the former obtains in nearly
or quite all extensive works, while that of the latter is
mostly limited to the test-room and experimental operations.
For the full treatment of ores, auxiliary machines,
common to, the two, are employed. Of these the RockBreaker, Amalgamator and Separator may be mentioned.
The most efficient and economical quartz machinery thus
far introduced for the mechanical reduction and concentration of ores and rock containing the precious metals,
and for the purposes of amalgamation and subsequent
treatment, consists, aside from prime movers, common
connections and tanks, chiefly of the Rock-Breaker,
Straight Batteries, Grinders and Amalgamators, Separators, Concentrators, Retorts, Crucibles, and Ingot
Molds.
ROCK BREAKERS.
Rock Breakers are machines chiefly employed for the
crushing of rock, as it comes disengaged from the mine,
quarry or other bed, to fragments an inch, half inch or




QUARTZ Mt &CI-INERY.            39
so in diameter. For this work they are fast supersedilg the " Cornish Rollers " and "Heavy Stamp "-ill fine,
all other machinery designed for like purposes. They
have also been employed for the pulverization of ores
and rock, but have not been sufficiently successful to
warrant their use in this department.
The nearly upright jaws with convergent crushing
faces constitute one of the chief features of Rock Breakers. These are caused by means of machinery crank, or
its equivalent, directly or indirectly applied, alternately to
recede from and approach each other. In some machines
one, and in others both jaws are movable; and in some
cases they have, additional to the vibratory, a lateral or
vertical grinding or other compound motion.  The
"Blake Stone Breaker" has one of its jaws stationary,
the other movable. In the upper end of the latter is the
centre of motion.
The inventor, in describing the operation of the machine,
says " every revolution of the crank causes the lower end
of the movable jaw to advance toward the fixed jaw
about ~ of an inch and return. Hence, if a stone be
dropped in betweep the convergent faces of the jaws, it
will be broken by the next succeeding bite; the resulting fragments will then fall lower down and be broken
again, and so on until they pass out at the bottom. The
ditsance between the jaws at the bottom, which limits
the size of the fragments, may be regulated at pleasure."
The " Blake Stone Breaker" may be mentioned without any disparagement to others of its class as having




40       QUARTZ OPERATOR'S HAND-BOOK.
made for itself, in the Pacific gold and silver regions, an
enviable reputation. One of these machines, with a feed
opening of nine by fifteen inches area, is found capable of
reducing from one hundred to one hundred and fifty tons
of hard rock per day to a size suitable to be fed into
Batteries.
The machine of the size mentioned weighs 11,600
pounds, and requires six-horse power to reduce seven and
one-half tons of rock per hour.
BATTERIES.
The Battery embraces the frame (usually made of
wood), Mortars, Cams, Cam-Shaft, Tappets, Stamps,
Stamp-Stems, Shoes, Dies, Guides and Screens.
MORTARS.
EHigh.Mortar.-The High Mortar is represented by
Figs. 2 and 3. Fig. 2 shows a front and Fig,. 3 an end view
of the mortar mostly approved on the Pacific coast and
wherever else it has been employed for the reduction of
ores containing the precious metals. B represents the
feed opening, and C the screen opening. The screen is
fastened by nails or screws to the screen-frame, which by
wedges is firmly secured in grooves provided for its
reception at the ends of the mortar, and by two " lugs,"
seen at the bottom of the opening C.
Mortars, for working on a large scale, are constructed




QUARTZ MACHINERY.                41
for three, four, five or six stamps each. Millmen and
quartz operators, from long experience, are unanimous in
opinion that the five-stamp mortar is preferable.
FIG 2.                   1FG. 3.
II  i i
HIGH MORTAR (Front View).    HIGH MORTAR (End View).
Section Mortar.-The Section Mortar, designed for
places of difficult access, can readily be taken apart and
packed on mules. The Section Mortar may be high
or low. It should only be employed in extreme cases,
owing to its cost and greater liability to destruction
than that of the Solid Mortar.
D2ouble Discharge l2ortar.-Fig. 4 shows a side and
Fig. 5 an end view of the Double Discharge Mortar. A A
represents the doors, B the feed opening; C the screen.
The doors A A are lined on the inside with copper plate,
as shown by the thick black lines. This style of mortar
is designed more especially for the working of gold bear



42         QUARTZ OPERATOR S HAND-BOOK.
ing rock-. By removing the screen C and carrying the door
somewhat higher, we have what is known as the Float
Mortar. By substituting the door A for a screen, we
bave the High Mortar, as shown in Figs. 2 and 3,
which is in most general use for the working of both
gold and silver ores.
FIG. 4.                   FIG. 5.
_....l.I.'...-I.M.M
-..           I    11.......   M i
DOUBLI&-DISCHARGE MORTAR.    DOUBLE-DISCHARGE MORTAR.
(Side View.)              (End View.)
Dry.Mortar.-The chief difference in construction,
usually, between the "wet" and "dry working mortars " is that the screens to the latter are higher or wider
and at a less inclination to the horizon than in the former,
besides being made of wire cloth instead of Russia iron.
In the "Wheeler and Hotaling Dry Mortar" no screen is
used; in this machine the discharge-opening is about six
inches wide and between two and three feet above the
die.  The ore pulverized very fine, rises to the discharge-opening, and thence passes through an exhaust




QUARTZ MACHINERY.              43
fan or blower into the settling chamber, from which an
escape or air-supply pipe leads back to the battery. It
has been proposed to employ a current of steam instead
of thefan, but not aware of its having been put in practice, the writer cannot confidently speak of its worth.
The Low MJortar.-The Low Mortar is less used than
formerly. Its use, however, is far from being abandoned.
The most improved low mortar is constructed with framegrooves and discharge-lips.
TAPPETS.
The Tappet is the head, or machine secured to the
stamp-stem, by which the cam raises and lets fall the
stamp upon the substance to be crushed. Fig. 6 represents the Plan, and Fig. 7 an elevation of the "Gib-tapFIG.. 6.                     FIG. 7.
PLAN (TArrPET).             ELEVATION (TAPPET).
pet "-one of the many very valuable inventions in quartz
machinery of Zenas Wheeler, Esq., of Wheeler & Randall.
B, in Fig. 7, represents the "gib," and A A the keys by
which the tappet is firmly secured to the stem.




44        QUARTZ OPERATOR IS HAND-BOOK.
By this invention, no cross and weakening key-seats
in the stem are required; besides, it can readily be adjusted to any desired point. It surpasses in excellence
any other in use for like purposes.
CAMS.
The Cam is a machine employed to raise the stamp to
any desired height, and then allow it to fall by its own
gravity upon the substance to be crushed. Cams, in
quartz machinery, are constructed with one, two or three
arms. The "three-armed " cam is but little used, as by it
Fir. 8.
SINGLE-ARMED CAM.
a less number of drops to the stamp can be obtained than
by either of the other styles mentioned. Fig. 8 represents the "one" or "single-armed" cam, and Fig. 9
the "two" or "double-armed" cam. By the " single



QUARTZ MACHINERY.                  45
armed" cam, when properly constructed, ninety ten-inch
drops per minute are obtained with safety and economy.
The proper curve of the               FIG 9
cam-arm, so as to run with
the least firiction,  is a
modified involute of a
circle, whose radius is
equal to the horizontal
distance between the centre of the cam-shaft and
the centre of the stampstem. The cam-arm should
have a greater or sharper
curvature near each of its
ends than the regular involute of the circle. The
objects of this are: 1st,
to receive the tappet at
the least practical distance from the centre of
the cam-shaft, where the
concussion is less than at
a greater distance; and
2d, to prevent the sharp
end of the cam from tearing along the face of the
tappet, friom a point near
DOUBLEM-ARMED CAN,
itscentre to its outer edge
or point of delivery. The outer end of the cam-arm is




46-        QUARTZ.OPERATOR'S HAND-BOOK.
fashioned so as to conform to the outer edge of the
tappet, which is circular.
It seems proper to remark, since the curve of the camarm is determined in reference to the distance between
the centres of the cam-shaft and stamp-stem, that this
distance in the practical erection of the machinery should
never on any account be changed in respect to the same
curve.
CAM-SHAFT.
The Cam-Shaft is a round bar of iron, turned, finished,
and having one and sometimes two key-seats cut in it
lengthwise, between its journals, for the securing of the
cams in their places. For stamps of ordinary weight,
the cam-shaft is usually made about four and one-half
inches in diameter. Sometimes one shaft is employed to
run fifteen or more stamps. An independent cam-shaft,
however, for each battery of five stamps is much more
preferable; in which event, if there is a line of several
batteries, a counter-shaft is usually employed.
STAMPS.
Fig. 10 represents the Stamp-head or socket, including portions of the stamp-stem and shoe. C C, C C,
represents wrought-iron hoops; D D, key-ways, the
keys being used for forcing or driving out the stamp



QUARTZ MACHINERY.               47
stem and shoe from the stamp-head or socket, when
necessary.  A represents the stamp-stem, and B the
stem of the shoe.
The stamp, in a broad signification, embraces the tap.
pet already described; the stamp-stem, which is a round
bar of wrought iron, turned and finished; and the stampFia. 10.
STAMP-HEAD.
head or socket, which is made of the toughest cast-iron, in
the upper end of which the stamp-stem is firmly secured in
a slightly conical opening, and in the lower end of which
is a larger conical opening; into this is fitted with wooden
wedges the stem of the shoe, which may be removed at
pleasure. The shoe should be made of cast-steel; white
iron, however, is usually employed. The round stamp
has almost entirely supplanted the use of the square.




48         QUARTZ OPERATOR'S HAND-BOOK.
DIES.
The Dies are made of. cast steel, or the same quality
of iron as the shoes, and are fitted into the bottom of the
mortar. These may also be removed at pleasure. Some
dies are round, and are fitted into recesses of correspondFIGS. 11, 12.
STAMP-SHOE AND MORTAR-DIE.
ing forms in the bottom of the mortar; others are nearly
square. There should always be the same number of
dies as stamps in a mortar. In Figs. 11 and 12, S
denotes the stamp-shoe, and D the mortar die.
SCREENS.
The Screen used for working ores by the wet process
is made generally of.Russia sheet-iron. This iron has a




QUARTZ BIACHINERY.              49
planished, glossy and smooth surface of gray oxide of
iron; it should be free from rust or flaws, and be very
soft and tough. The severest test of sheet-iron consists
in hammering a part of the sheet into a concave form.
In the manufacture of this kind of screens, the sheet is
perforated by punches varying in size from the number
nine to the number one common sewing needle.
The screen used for working ores dry is usually made
of wire, and varies in fineness from nine hundred to ten
thousand meshes to the inch.
GUIDES.
The Guide in which the stamp runs is generally made
of the firmest wood, which can easily be obtained, and is
secured by bolts to the cross-ties of the battery frame.
It is constructed in halves, so that when the stem-way
through it, or between its parts becomes worn, it may be
refitted to the stem by dressing down its faces.
GRINDERS AND AMALGAMATORS..Machines in almost endless variety have been employed for the reduction of ores from a granular state to
an impalpable powder or slime condition, and for the
amalgamation of the precious metals. Of all these the
most efficient in use are technically termed " Grinders
and Amalgamators." The Grinder and Amalgamator
is a large pan provided with grinding plates which op



50        QUARTZ OPEIRATOR' S HAND-BOOK.
erate similar to millstones. The upper plate, called a
"muller," revolves, and besides grinding, incorporates
the quicksilver into the charge of ore under treatment.
On the Pacific coast, Grinders and Amalgamators are
employed almost to the entire exclusion of all other machines invented for like purposes. They take their respective names from the several forms of their grinding
surfaces, and may be properly classified as the Tractory,
Plane and Conical.
WHEELER AND RANDALL'S EXCELSIOR
GRINDER AND AMALGAMATOR.
In the Tractory Conoidal machines, the grinding surfaces, or surfaces of revolution are generated by revolving the tractory curve round its directrix as an axis.
The invention embraces two styles of machines-one
called the "Tractory Conoidal Grinder and Amalgamator," the other, the " Excelsior Grinder and Amalgamator," represented in the annexed cut. The former of
these machines has the greater base of its muller upward,
and the latter has it downward. The quicksilver in the
former is much less agitated than in the latter, which by
many operators is regarded a very valuable desideratum.
On the other hand the material to be amalgamated passes
direct from the grinding surfaces into the quicksilver, thus
precluding, after having been burnished, the possibility
of becoming coated with any foreign matter. Preference is mostly in favor of the Excelsior.




QUARTZ MACHINERY.
FIG. 13.
EXICELSIO R GRINIDER AN  AMALGAMATOR.
M 
C y1
I  l I.




VV 2       QUARTZ OPERATOR S HAND-BO lK.
Theoretically, also practically considered, the grinding
effect of either the "Tractory Conoidal " or the "Excelsior Grinder and Amalgamator" are fifty per cent.
greater than that of the Plane, and thirty-fbur per cent.
greater than that of the Conical Pan of the same size.
The reason for this great inequality is that the vertical
wear of the tractory-formed grinding-plates is uniform,
whereas in the plane and conical pans the more central
portions of the grinding-plates impede the wear and consequent grinding effects of the less central portions. The
grinding-plates under consideration are subject to the
same laws as pivots-in fact are but large pivots-on
which subject see ".Des Ingenieurs Taschenbuch," pages
143 and 144-" Weisbach Mechanics,'" paes.313 to 318
inclusive -Professor Rankine's "Manual of the Steam
Engine and other Prime Movers," page 17-M. M. Armengaud, sen., Armengaud,jun., and Amouroux's"" Practical Draughtsman and Book of Industrial Design," pages
181 to 183-and the supplement of Wheeler and Randall's " Quartz'Operator's Hand-Book "-First Edition.
The great popularity of the "Excelsior Grinder and
Amalgamator," however, arises not alone from its superior grinding properties, but among other things, from its
unequalled stability and convenience of working and
cleaning up. Thus, when it is necessary to put in a new
set of shoes and dies, or to clean up, instead of employing
fall and tackle, levers and skids, with waste of time and
much hard work, as is the case in other pans, the muller
of the Excelsior, by means of the screw at the centre, is




QUARTZ MACHINERY.               53
raised with the utmost facility entirely out of the way of
the operator.
The form of the hub and stationary grinding-plates
pitching down toward the circumference also greatly
facilitate the drawing off the pulp and "cleaning up."
When, from stopping the mill or other causes, the pulp
in the pan becomes too firmly packed to allow starting
the muller by means of the hand-wheel at the side of the
pan, it is readily accomplished by removing the key in
the centre-screw. The muller, rising, breaks up the pulp.
Then, at the pleasure of the operator, it is lowered and
secured by the key being returned to its place.  For
the practical uses of the Excelsior Grinder and Amalgamator, see " Treatment of Silver Ores by Amalgamation
-Pan process."
This machine is so constructed that it is readily converted into a continuous Grinder and Amalgamator.
Openings on its side at different elevations are prepared
for the reception of a discharge-tube, which extends near
the centre of the pan, where the material under treatment
is lightest and least agitated.
SEPARATORS.
These machines differ in form from each other almost to
an unlimited extent. The term "Separator," in general,
embraces that class of inventions designed for separating the amalgam and precious metals from their " pulp"
or gangue. The machines to which it has comne more




64        QUARTZ OPERATOR'S HAND-BOOK.
specially to be applied are large pans, varying from four
to say ten feet in diameter, and from one to four feet in
depth. A common size is seven feet diameter and two
feet deep. If they are made much larger than this, the
central portions of the mass being operated on are apt to
"pack," while those at the circumference are undergoing
proper treatment; or on the other hand, the outer portions.
become too much agitated, while the inner are being well
worked. They are named according to the form of their
respective bottoms, to wit: the Plane, Concave and Conoidal,
In the Plane, the quicksilver spreading over the entire
bottom is apt to be ground with the gangue instead of
parted from it.
In the Concave, the ore being deepest at the centre
where the motion is least, tends to " pack," thus preventing separation from taking place.
To avoid these fatal objections, and otherwise simplify
and facilitate the work of the operator, -the Conoidal
was invented, which it is proposed to describe somewhat
in detail.
WHEELER AND RANDALL'S CONOIDAL
SEPARATOR.
The Conoidal Separator has a curved bottom. The
curvature decreases from near the centre towards the
circumference, where, with the exception of a bowl and
spiral groove for quicksilver, the surface is nearly flat.




QUARTZ MACHINERY~                55
By this happy device, uniformity of motion and mixing
of the material under treatment are secured; "packing
of the pulp" about the centre, or grinding of the quick-:FIG. 14.
l
CONOIDAL SEPLARATOR.
silver with the gangue, as experienced in other separators,
is obviated, and the labor of "cleaning up" is greatly
lessened and simplified. This machine is provided with
a large screw at the centre, by which the muller can




56        QUARTZ OPERATOR'S HAND-BOOK.
readily be raised entirely out of the way of the operator.
It also has the " Patent Self-regulating Quicksilver Discharge Apparatus," which is a very useful and great
labor-saving machine. The capacity of the Conoidal Separator is rated at ten tons of ore in twenty-four hours.
See "Treatment of Silver Ores by Amalgamation-Pan
process."
CONCENTRATORS.
The term " Concentrator" may in general be applied
to any device made for separating the heavier portions
of granulated or finely-broken ore from the lighter.
Generically, concentrators are to be classified as the
"dry " and the " wet." Relative to the former, reference
is made to the article on the reduction and concentration
of ores-dry way. As to the latter, those in most common use are, the Hand or Box Buddiles; Revolving
Buddles; Jiggers; Dolly Tubs; Sludge Dressing Machines; Tables, differing in size, structure and motion;
Cradles; Hides of animals, having the hair on; Riffles;
Blankets to be washed by hand; Revolving Blankets;
and machines of more recent construction and specially
known as "Concentrators."  As a general rule, the reduced ore should be carefully sized before being dressed
by almost any one of the machines enumerated. On
this continent, however, it is not usually done.  The
sizing may be effected by revolving sieves running in
water.




QUARTZ MCHINERY.               57
The Concentrators which seem most entitled to consideration are the " Eureka" and the' "Tabular."
WHEELER AND RANDALL'S EUREKA
CONCENTRATOR.
This machine in some of its features does not essentially differ from the "-Sludge dressing machine," quite
favorably known in Europe. In comparison, however, it
possesses some very important advantages over that
machine. Thus it concentrates more rapidly and is continuous working, both as to the dividing or separating
of the ores according to their specific gravities, and the
discharging of the quicksilver collected. The diameter
of this machine is about five feet. The form of the bottom is that of a double-inclined plane, whose upper edge
coincides with the diameter, and is at right angles to the
horizontal driving-shaft. Its motion is angular'and vibratory. It has a central opening, like the ".Sludge dressing machine," for the discharge of the gangue. At
each of its lower sides is a long narrow opening through
the rim, for the discharge of the ore concentrated into
the "sulphuret box," whence it is delivered continuously as gathered into -the tank below. The invention.Jof this continuous discharge:apparatus was patented
by Mr. Wheeler in 1864, and it is to be regretted that
certain soi disant inventors:are appropriating it to their
own uses with unwarrantable freedom. At the circumference of the pan-bottom are depressions for collect3*




58        QUARTZ OPERATOR'S ITAND-BOOK.
ing quicksilver, which is conducted off as gathered by
means of The Wheeler Patent Self-regulating Quicksilver Discharge Apparatus.
The Concentrator has a conical-formed cover, at the
centre of which is a large bowl. Near the circumference of the cover is a circular screen. The material to be
treated is run into the bowl; thence flows over the cover
through the screen into the pan, and is then disposed of
as before described.
THE WHEELER AND RANDALL TABULAR
CONCENTRATOR AND AMALGAMATOR.
In the accompanying Fig. 15 of The Wheeler and
Randall Concentrator and Amalgamator, A represents
the frame; B, head of the table; E, sulphuret-box; I,
discharge-pipe; H, bottom of table; L, copper plate,
silvered; P, shower-pipe; T, connecting-rod; D, self.
discharging quicksilver apparatus; C, receiving-trough,
perforated at the bottom and secured to the head B.
The bottom of the head-end is about four inches lower
than the opposite or discharge-end. The table has a
vibratory or pendulum motion at right angles to the
current of pulp and water passing through it. The
vibrations are three inches in length, and three hundred
and sixty a minute. The material,, as it comes from the
stamps or other reduction works, passes direct into the
receiving-trough, thence is showered into the main table.
By the quick, short, vibratory motion the material is




10CT~ ~ ~~~~~~~~~~                   j FxIGa. 15.
TABULAR CONCENTRATOR AND AMALGAMATOR.




60        QUARTZ OPERATOR'S' HAND-BOOK.
kept buoyed up, or prevented from packing; at the same
time the precious metals and the heavier portions of the
material being treated (almost ever the richer portions
of the ores) by their specific gravity, sink to the lowest
depths in the table. The substances subject to amalgamation are taken up by the quicksilver lying in the deepest part of the table. The sulphurets and heavier portions of the ores pass into the sulphuret-box through a
small opening in the head, about. one inch and a half
above the table bottom. The agitation in the sulphuretbox, owing to its shorter length, being much greater
than the agitation in the main table, the sulphurets and
heavier portions of the ores are thrown backward and
forward in the direction of the motion to the ends of the
box, and pass through a small adjustable opening into
the discharge-pipe I, thence into the tank below. So
simple is this apparatus that the utmost novice can
readily adjust the pipe so as to obtain any desired percentage of the heavier portions of the ores under treatment. The lighter and poorer portions of the ores pass
in a thin sheet, being triturated at the same time over
the silvered plate L, off at the discharge-end, opposite to
the head B of the table.
From the pipe P, water is continuously thrown in a
fine shower upon the silvered plate L. The effect of this
shower is to keep the plate clean, thoroughly wash the
material under treatment, and send back any particles
that may have otherwise escaped. To the credit of the
machine, however, as reported by the most experien



QUARTZ MrACHINERY.              61
ced manipulators of ores, the copper plate and shower
pipe scarcely pay the slight expense of their first cost, so
effectual has been the operation of the table on the ores
prior to their reaching the plate in question. The quicksilver is kept at any desired height in the table by means
of the self-discharging quicksilver apparatus D. The surplus quicksilver, as it comes from the reduction works,
flows off into a vessel prepared for its reception. The
amalgam gathered in the bottom of the table may be
" cleaned up" from time to time according to the wish
of the operator.
For the treatment of most ores, as a general rule, the
weight of water to that of ore should be as four and a
half to one. The stream of pulp should flow uniformly
into the machine. The capacity of the machine is rated
at five tons of ore in twenty-four hours. A much larger
quantity per day has been treated in it with entire success. The frame should be well secured by bolts to a
good foundation.
RETORTS.
Retorts, with their appurtenances, are vessels employed in " distillation" and " sublimation."  The operation is termed " sublimation " if the resulting product
is a solid, and "distillation" if it is a liquid or fluid. The
operation of vaporizing the mercury of gold and silver
amalgam, of conducting away and condensing the vapor,
is termed "retorting."  Retorts for this purpose are
usually made of cast-iron. Their shape and dimensions




62        QUARTZ OPERATOR'S HAND-BOOK.
vary according to the caprice of the constructor as well
as the amount of work to be performed.
GOLD  RETORTS.
The Gold Retort is a conical-shaped vessel, having its
smaller end or bottom usually rounded. The cone is
secured to the mouth or larger end by means of a clamp
and wedge. The joint between the cone and rim of the
retort is made tight by means of loam or clay. The
shorter leg of a syphen-formed exhaust-pipe is screwed
into and through the cover; the other and longer leg is
made to pass through the condenser, which is a simple
vessel kept filled with cold water while the retort is in
use.  Sometimes instead of a vessel as a condenser,
cloths kept wet with cold water are wrapped round the
pipe. The inside of the retort, before being used, should
be rubbed over with chalk, flour, charcoal, or like substance, to prevent the amalgam from sticking. It is not
advisable to fill the retort over two-thirds full, lest, by
its expansion, the vapor or exhaust-pipe becomes choked,
and the apparatus bursts in consequence. The heat at
first ought to be gentle, and applied to the shorter leg
of the pipe and upper part of the retort; then to all parts
of the body of the retort alike. The heat may then be
gradually increased, but never raised to a degree much
above a bright cherry red. The quicksilver, on being
condensed, flows into the receiver, which is generally
kept filled with water.




QUARTZ MACHINERo.               63
SILVER RETORTS.
The Silver Retort, as it is called, is as well adapted for
the retorting of gold as of silver amalgam, when the
quantity is large. The most approved retort is the cylindrical. Some of the advantages of this style are, that
it can be turned so as to substitute a sound for a burnt
side, without destroying the brick-work; also, for a similar reason, it can be replaced by a new one. For example, a retort formed of convenient size and proportions is sixty inches long; the main or cylindric portion
on the inside (thickness of metal one and one-half inches,)
is twelve inches in diameter and thirty-six inches in
length; the neck, of conoidal form, is twenty-four inches
long and two and one-half inches least inside diameter.
There is a flange on the end of the neck to which the
exhaust-pipe is secured by bolts. This pipe, the retort
being properly set much like the common horizontal
flue boiler, turns downward at right angles, and passes
through the condenser. When in use, the condenser is
kept filled with cold water to the height of the dischargepipe near its top, by a small supply-pipe which reaches
near its bottom. The quicksilver-receiver, placed under
the end of the exhaust-pipe, is kept nearly full of water.
The other end of the retort has an angle, flange or hood,
into which the door is fitted. Within the cylindric portion of this flange, or hood, are two inclined or helixformed lugs opposite each other. A "bar," turning upon




64         QUARTZ OPERATOR'S IHAND-BO(OK.
a pin in the centre of the door, holds it firmly in its place,
by the ends of the bar catching under the inclinecl or
screw-formed lugs. The joint between the door and bottom of the flange is made tight usually by means of clay
luting.
Two tiers of amalgam trays may be used in this retort at the same time, one above the other. The bottoms
of the lower tier are circular, so as to conform to the
shape of the retort.  When the retort is in use, temporary brick-work is sometimes built up in front of the door
to prevent the escape of heat.
CRUCIBLES.
Crucibles are small conical vessels, narrower at the
bottom than at the mouth, for reducing ores in docimacy
by the dry analysis, for fusing mixtures of earthy and
other substances, for melting metals and compounding
metallic alloys. They ought to be refractory in the
strongest heats, and not readily acted upon by the substances ignited in them, not porous to liquids, and capable
of bearing considerable alternations of temperature without cracking, on which account they should not be made
very thick. The best crucibles are formed from a pure
fire-clay, mixed with finely-ground cement of old crucibles, and a portion of black-lead or graphite. Some
pounded coke may be mixed with the plumbago. The
clay should be prepared in a similar way to that for
making pottery-ware. The vessels, after being formed,




QUAR'TZ MACHINERY.              65
must be slowly dried, and then properly baked in the
kiln.
Black -Lead Crucibles are made of two parts of graphite and one of fire-clay mixed with water into a paste,
pressed in molds, and well dried, but not baked hard in
the kiln. They bear a higher heat than the Hessian crucibles, as well as sudden changes of temperature; have
a smooth surface, and are therefore preferred by the
melters of gold and silver. This compound forms excellent small or portable furnaces.
INGOT MOLDS.
Ingot Molds are simple troughs made of cast iron.
They are slightly wedge-formed, the cavity being somewhat larger at the top than at the bottom. For example,
the inside of an ingot mold two inches by six inches at
the bottom and two inches in height, should be about
two and one-eighth inches by six and a quarter inches at
the top. The inside of the mold should be oiled before
being used.
It is customary to put the nominal capacity of the
ingot mold per cubic inch for gold at one hundred and
twenty-five dollars, and for silver at four and one quarter dollars.




STAMP MILL.
The expression "Stamp Mill," in a limited sense, signifies simply the batteries; but in a broader sense, embraces not only the batteries but the prime movers and
all the machinery applicable to the reduction and concen
tration of ores, amalgamation and further treatment of
the precious metals.
The work to which stamps are peculiarly well adapted
is the reduction of fragmentary ores coming from the
rock-breaker to a granular state, so as to pass through
No. 4 or No. 5 screens. In this capacity, stamps arranged
in straight batteries are unrivalled in efficiency, durability
and simplicity. To accomplish the same kind of work,
thousands of different machines have been put in operation. These invariably have proved so many failures,
and have shortly found their way to the furnace, or been
left where first reared as monuments of a sad experience.
A stamp weighing six hundred and fifty pounds, and
making ninety twelve-inch drops a minute for twentyfour hours, reduces about two and one-half tons of hard,
tough rock from and to the respective sizes named, and
requires nearly one-horse power for each ton of rock so
reduced. For the reduction of gold and silver ores the
usual ratio by weight of water to that of rock is as four
and a half to one, while for the Lake Superior copper
ores the ratio is as twenty to one by volume.




S'TAIMP MILL.                 67
The feeding of the rock into the battery should be
uniform.  The practical rule is to so feed that iron to
iron shall be heard as often as every tenth or fifteenth
fall of the stamp.
Looking to the erection of a Stamp Mill, location is a
subject of scarcely less importance than that of determining the prospective value of the vein or mineral deposit
for which the machinery is designed.  The site should
be selected with a view chiefly to its elevation, its accessibility to the mine and common thoroughfare, and to the
facilities offered by the surrounding country for fuel, timber and water. The height of the elevation for immediate mill purposes should not be less than twenty feet;
besides, the fall below for carrying off the tailings should
be at least one and a half inches to the foot, unless there
may be a surplus of water.
The floors of the mill should be arranged in steps so
that the material under treatment shall pass from machine to machine through the series with the least handling. To secure the best results the foundations of all
the machinery must be firm-those of the mortars in particular. The timber in mortar foundations is placed, as
to its grain, either horizontal or vertical. The horizontal foundation is composed sometimes of a single timber,
and sometimes of several. In either case they are laid
across mud-sills, or on brick or stone work. A single timber, termed a " mortar block," being employed, the mortars are secured in their places either by large bolts or
by being let into it. If several sticks (usually three) are




68         QUARTZ OPERATOR S HAND-BOOK.
used, they are bolted together, one acting as a bed for
the mortar and the other two as side clamps. The vertical foundation is constructed in distinct sections, each of
which, designed for a single mortar, is composed of several timbers framed and securely bound together with
bolts, keys and hoops. In case of their being several
sections, they are connected by clamps running lengthwise of the batteries. The bed-rock is usually sought as
the base of the vertical foundation, but when this lies
too deep, resort is had to mud-sills, brick or stone work.
The end of each frame of timbers should be dressed
level and smooth so as to make an accurate fit with
the planed bottom of the mortar, which is to be bolted
to it. The vertical foundation is preferable to the horizontal, for being separate from the battery frame, the
jar occasioned by the fall of the stamps is not communicated to the other machinery. It is also firmer, thus
rendering the blow of the stamp more effective. Besides,
in case of decay it can readily be repaired without detriment to the frame of the battery.
Water and steam being common to most driven machinery, a description simply of the principal modes of
their connection with the quartz machinery of Stamp
Mills is in this place deemed sufficient. The main drivingshaft is in some instances coupled with the cam-shaft,
and in others is connected with it by means of a counter-shaft and gearing, or belts and pulleys. When the
coupling is used, the cam-shaft is frequently employed
as a driving-shaft for the other machinery. In case of




STAMIP MIL.                   69
the counter-shaft being adopted, it is usually placed at
the foot and in front of the batteries, but sometimes is
put from  fifteen to twenty feet from them, and ten or
more feet above the level of this position. The connection between the intermediate and motor-shafts may be
made by direct coupling or by intervening machinery.
The stamps, grinders and amalgamators, and commonly
the separators are driven by this shaft.
Another counter-shaft for the rock-breaker, and subcounter-shafts deriving their motions from the main intermediate shaft, for driving respectively the amalgamators
and the concentrators, are generally introduced.  Wher
the elevated counter-shaft is employed, the rock-breaker
is driven by a sub-counter-shaft placed on the top of
the battery frame. As a general proposition the application of intermediate shaftso is preferable to that of
direct couplings; for in the former case, the batteries
and the amalgamating machinery may be run or stopped
at pleasure, the one without interfering with the other;
whereas in the latter case, the amalgamating machinery,
receiving its motion through the cam-shaft, is subject to
all its delays. Besides, both the motive machinery and
that driven from the cam-shaft are exposed to no little
wear and tear, arising from the jar produced by the fall of
the stamps and the concussion of the cams and tappets.
But whether it is better to put the intermediate shaft near
the foot of the battery or to elevate it as described, is not
fully settled.  If it is placed in the lower position its journals and bearings, without extreme care, are liable to be




70         QUARTZ OPERATOR'S HAND-BOOK.
injured by crushed ore from the battery getting into the
pillow-blocks. Another important objection is that the
cam-shaft belt is rendered, too short to secure the best
mechanical results; otherwise, as the running machinery is entirely out of the way of the workmen, the plan
seems almost faultless. The shaft placed in the upper
position, these objections do not apply; but one well
worthy of no little attention does: the framework for
the running machinery, the belts, tightening pulleys and
other appliances taking up much valuable room, restrain
the operations of the workmen.
Having described in preceding articles, somewhat in
detail, the best known quartz machinery, and discussed in
the present article the leading features of Stamp Mills,
it is now proposed to consider Silver and Gold Mills, with
reference to the arrangement of the machinery and the
modes of operating it.




SILVER MILL.
Aside from motors and connecting machinery, the
principal machines of a Silver Mill are the Rock-breakers,
Batteries, Tanks, Grinders and Amalgamators, Separators, Concentrators, Retorts, Crucibles and Ingot Molds.
Rock-.Breakers.-The ore, as it comes in blocks from
the mines varying in size from a hen's egg to that as
large as a man can well lift, is fed into this machine,
which reduces it to an inch or so in diameter. A Blake
Stone Breaker (see description) with a feed opening nine
by fifteen inches area, the crank making one hundred and
eighty revolutions a minute, reduces from one hundred to
one hundred and fifty tons of hard rock in twenty-four
hours to a size suitable to be fed into the batteries, and
requires about six-horse power. The rock, or ore, as reduced, falls upon the battery "feed floor."  Prior to the
introduction of the rock-breaker into the mines the ore
was " spalled" by hand-rollers or by stamps weighing a
thousand or more pounds and having a fall of at least
three feet. Ore is still prepared for further reduction by
hand, when the amount does not exceed fifteen or twenty
tons a day.
Batteries.-The Batteries succeed the Rock-breaker at a
distance of twelve or more feet. The "feed floor" of the
former, depending on the available fall, is ten feet, more




w~~~~~~~~~~~~~~~~~~~~~~~I
___F 1LLI
0.                                                                                           _ _ _
IlWF               1I
logic l I
rllI111iirl  ill  j  ii~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~1 ~,Ml
W                                                                                   II~~~~~~~~~lla~~Jl
p,   iiii I!I.~~~~~~~~~~~~~~~~~~TRSl
FIG. M.-CA LIFORIA ILVR MLL




SILVER MILL.              -73
or less, below the floor of the former. The feed floor
should be nearly level with the feed opening in the batteries, so as to save the labor of lifting the ore. It is
often from two to three feet below, but no good reasons
can be assigned for this plan. The feeding of the ore
should be uniform-(see description of Gold Mill). The
material fed into the batteries being reduced sufficiently
fine to pass through No. 4 or No. 5 Russia iron screens,
flows into the tanks. It is customary to estimate that
each stamp weighing six hundred and fifty pounds, and
making ninety ten-inch drops per minute, will crush
about two and one-half tons of hard rock in twenty-four
hours, and requires nearly one-horse power for each ton
reduced. As a general proposition, all the conditions
complied with, this is near the truth; but owing to the
lessening weight of the stamp by wear, and the unavoidable hindrances to continuous running, two tons a day
for any considerable time may be regarded good work.
ITanks.-The Tanks come next, and are usually set
with their tops level with the upper side of the sills of the
battery frame. They vary greatly in size. A common
size is five by seven feet, and three feet deep. In these
the ore is well settled, so that the water runs off quite
clear. Proper " settling" of the ores is a matter of vital
importance. The tank capacity cannot be too extensive.
It is well to arrange these machines in a series, so that
the ore borne along by the water through the first of the
series may be deposited in the second or third, and so on
to the satisfaction of a rigid test. Silver ore, for the most
4




74         QUARTZ OPERATOR'S HAND-BOOK.
part being very friable to no little extent, becomes so fine
in the process of reduction as readily, without extreme
care, to pass off in the current of water. While a'" charge " is being taken from one tank, the stream of ore
and water from the battery is turned into another of the
receptacles. The capacity of a tank of the proposed
dimensions is between four and five tons of ordinary
crushed ore.
Grinders and Amalgamators.-These machines are
placed near the tanks with their rims level with the
tops of the latter. The "Excelsior Grihders and Amalgamators," with muller four feet diameter, require about
five feet fall and seven feet run, including the platform.
A less fall, however, will suffice by setting the separator
with its top just below the level of the discharge-opening
of the machine under consideration. In these machines
the ore from the tanks is worked in charges and reduced
to an impalpable paste or slime, or " slum "-(see " Treatment of Silver Ores by Amalgamation —Pan process.")
An " Excelsior " of the proposed size, the muller making
sixty-five revolutions a minute, will reduce full five tons
of ore in twenty-four hours, and require about five-horse
power.
Separators.-The Separator follows the Grinder and
Amalgamator. It is placed sometimes so that one of
its sides is under the platform of that machine, and
sometimes just from under it and more elevated, as suggested above. The Conoidal Separator, seven feet diameter, requires of itself from four to five feet fall and




SILVER MILL.                  75
nine feet run, including platform.  As to details for
operating this machine, see "Treatment of Silver Ores
by Amalgamation-Pan process." In it can be well
worked about ten tons of ore a day, at an expense of
one horse power, providing the ore is not allowed to
pack.
Concentrators. —The Concentrator succeeds the Separator, and requires, in case of the Tabular being employed, about three feet fall and ten feet run.  (For a
particular description of this machine, see "Tabular
Concentrator.")  The ore runs from the separator into
it. The lighter and poorer portions of the material flow
off at the discharge end, and the heavier and richer portions pass off at the sulphuret-pipe into the tank. It is
capable of working from five to ten tons of ore a day,
and requires not to exceed one half of a horse power.
For description of Retorts, Crucibles and Ingot Molds,
the reader is referred to the articles under their respective heads.




GOLD MILL.
Gold Mills are in far greater variety than Silver,
for the reduction of the vein-stone, concentration of the
richer portions of the material under treatment, and the
amalgamation of the precious metals.
The same machines, that is, the rock-breaker, stamp,
grinder and amalgamator, separator and concentrator,
are employed both in gold and silver metallurgy, but
are subject to greater modifications in arrangement in
the treatment of gold-bearing rock than in the treatment of silver ores.
In the treatment of silver, all the ores that are
crushed are ground in pans, separated, etc., but in the
treatment of gold-bearing rock, modifications in the
arrangement of the machinery are made according to
the character of the gold,-viz.:
1st. If the gold is very fine and uniformly diffused
through the rock, the machinery as arranged under the
head of "Silver Mill" can be employed to advantage
for its treatment; except that it is advisable to employ a greater number of concentrators and amalgamators. The first series of these should be used immediately after the batteries, but simply as amalgamators.
The whole mass should be treated.
2d. If the gold in the rock is contained mostly in the




GOLD MILL.                  77
suiphurets, the concentrators and amalgamators should
be employed immediately after the batteries. The concentrated portions of the rock should be ground in the
grinders and amalgamators, worked in separators, and
finally treated in another series of concentrators.
3d. If the gold is quite coarse and clean in the rock,
it will not be advisable to employ grinders and amalgamators, and separators.
4th. If the gold is coarse and coated it is advisable
to work the rock by the "continuous process," as it is
termed.
Modifications in machinery, as observed, must necessarily be made according to the character of the gold
and the rock.
The weight of authority is, in wet crushing, in favor
of amalgamating in the battery. Great care in feeding
the quicksilver into the battery must be observed.
If too little quicksilver be fed the amalgam will be
dry and granular, and will readily pass off in the stream
of crushed ore.  If too much quicksilver be fed, the
amalgam will be liquid, and will readily flow off in the
current.
The quicksilver should be fed in small quantities into
the batteries, and fed often. It had better be fed by being
sprinkled through buckskin, or some other porous substance.
The rule to be observed is, to so feed the quicksilver
that the amalgam passing the screens may be indented
by a gentle pressure of the finger, and yet so firm as to




78         QUARTZ OPERATOR'S HAND-BOOK.
retain the indentation. Copper-plate, silvered, is sometimes employed both inside and outside of the battery,
but its use seems not well warranted. Its highest claim
as an amalgamator rests almost entirely on accident;
but though it cannot be relied on as safe, it at least is
harmless and cheap, and since the true principle is to
" catch" gold at all points where it can be done profitably, copper-plate, as an auxiliary, may perhaps be
employed sometimes with seeming advantage.




REDUCTION AND CONCENTRATION OF
ORES-DRY WAY.
The ore, broken to the size of hickory nuts, maize,
or so, is reduced by batteries (see Dry Mortar), rollers,
or grinders. The grinding-plates are usually of iron,
but sometimes of stone.
To fit the ore for concentration it should be granulated-rather than pulverized. At the same time, in
most cases, it has to be rendered quite fine to become
detached from its vein-stone.
Silver and Gold ores, for the most part, require finer
reduction than do those of Lead, Zinc and Iron. To accomplish fine granulation, none of the machines spoken
of are free from objections. Thus the batteries tend
to pulverize, so do the grinders; while the faces of the
rollers soon wear uneven and suffer portions of the ore
to pass too coarse between them. On the whole, however, for this class of work, rollers properly constructed,
arranged and cared for, are perhaps the least objectionable.
In further fitting the ore for concentration, it is to
be thoroughly dried and sized. The drying is effected
by the material being spread on heated plates, passed
through or over heated cylinders, let fall through currents of hot air, or otherwise exposed to the action of




80         QUARTZ OPERATOR'S HAND-BOOK.
heat. The sizing is accomplished by means of sieves or
wire-cloth bolts of different degrees of fineness. These
put in motion, the prepared ore is delivered into the
sieve or bolt of finest mesh; thence its unscreened portioiis pass into the next coarser bolt, thence into the next
coarser, and so on, tllrough the series. The tailings are
retlurned to the reduction works.
Machines of various devices for concentration, or
separating the heavier portions of ore from the lighter,
have been employed-some involving the well-known
principle of winnowing-some that of projecting horizontally from an elevated position, the material to be separated, into the air, which acting as a resisting medium
causes the ore to fall from the point thrown at distances
corresponding to the different specific gravities of its
granules having the same size and form-the heavier
being the more remote,  and others, that of sending
puffs of air up through shallow layers of the granulated
ore, causing its grains to become arranged vertically according to their respective specific gravities; when by
means of mechanical appliances their separation is completed. So far as appears, the successful application of
puffs of air to ore-dressing was first made by Mr.
Thomas J. Chubb, of New York. The writer has operated the Chubb Concentrator on the ores of leadgalena, with highly satisfactory results, and is credibly
informed that it has been worked on the ores of graphite,
nickle, cobalt, silver, gold, and iron with equally flattering success. The intensity of the puffs of air is to




REDUCTION AND CONCENTRATION OF ORES.   81
be regulated according to the fineness and specific gravity of the material under treatment. Thus the puff
barely of sufficient strength for the coarser portions of
the ore is found much too intense for the finer, which
goes to prove the absolute necessity of careful sizing.
The subsequent treatment of ores prepared in the dry
way is the same as that of those reduced in the wet,
that is, they are ground, amalgamated and separated in
the same manner-(see Pan process). As to the relative
merits of the two modes of reduction and concentration,
it is to be stated that larger yields of the precious metals may generally be obtained from the same amount of
ore prepared by the dry way than by the wet. The expense of labor and the destruction to life and machinery
are however greater, so that the wet, as before observed,
is almost universally adopted-at least on this continent.




EXAMINATION OF MINERALS.
The behavior of a mineral or metallic substance when
subjected to certain tests, such as being heated in glass
tubes, either closed or open, on charcoal, in the oxidizing
flame, melted in glass fluxes on platinum wire, treated
by acids and other reagents, determines its kind. When
borax is employed, it should be vitrified. The vitrified
borax is prepared by melting at a brown-red heat, in a
clay or Hessian crucible, common borax into a clear
transparent glass. It is preferable that the platinum
wire should have a small eye or loup at its test-end.
The spirit-lamp should be employed. To make the
borax-test, heat the test-end of the platinum wire to redness, dip it into the powdered borax, then heat again,
bring the borax globule in contact with the hot specimen to be tested, and apply the flame till the specimen
is dissolved. The color or other characteristics will show
what kind of mineral is under examination. The specimen, if metallic, with scarce an exception, should be
thoroughly roasted and its oxide subjected to the test.
Borax (biborate of soda). Before the blow-pipe (B B,)
intumesces and fuses to borax-glass; with fluor-spar and
bi-sulphate of potash, colors the flame green; soluble in
water, the solution changes vegetable blues to green.
iFluor-Spar (fluoride of calcium) B B, decrepitates and
fuses to an enamel; the flame continued, the specimen




EXAMINATION  OF MINERALS.           83
assumes a cauliflower appearance; heated with salt of
phosphorus in a glass tube, it etches or roughens the
inside of the glass.
Nitre-B B, deflagrates vividly, detonates with combustible substances, dissolves readily in water; not altered
by exposure.
Phosphorus moistened with sulphuric acid, and heated,
gives a green tinge to the flame.
Chlorine-A substance containing chlorine, combined
with the salt of phosphorus and oxide of copper, on the
platinum wire, colors the flame deep blue.
Quartz (silicic acid) undergoes no change alone; with
soda, readily fuses with effervescence to a transparent
glass.
Sulphur heated in an open glass-tube emits fumes of
sulphurous acid; heated with soda, the compound, moistened wiLh water, blackens silver.
Alumina (sesquioxide of aluminum) B B, unaltered,
both alone and with soda, fuses with borax with great
difficulty, also with salt of phosphorus; moistened with
cobalt solution and brought to a high heat, becomes
blue; is not attacked by acids.
Antimony (oxide) B B, readily melts, evaporates in
white inodorous fumes; colors the flame greenish-blue,
with borax, in oxidizing flame, forms a yellow glass,
which becomes colorless on cooling; in reducing flame
the globule contracts, becoming gray and vitrious;
with carbonate of soda, reduces to metal; is very friable
and brittle.




84         QUARTZ OPERATOR S HAND-BOOK.
Arsenic (oxide) B B, volatilizes in white fumes of
garlic odor; heated to redness, burns with a pale bluish
flame.
Bismuth (oxide) B B, evaporates, leaving a yellow
coating, on charcoal; color, on wire, hot, is dark browncold, is yellow; with borax, is colorless; with carbonate
of soda, on charcoal, reduces to metal.
Lime (oxide of calcium) B B, infusible alone; with
borax, effervesces; with comparatively large quantity of
borax, forms a clear glass which becomes angular on
cooling; in the flame of the oxyhydrogen blow-pipe
emits a most dazzling white light, and fuses at the edges.
Copper (oxide) B B, in the oxidizing flame, fuses; in
the reducing flame, forms metal; with borax, in the oxidizing flame, colors the glass green; in the reducing flame,
brown-red.
Cobalt (oxide) B B, unchangeable by itself; with
carbonate of soda, on charcoal, forms a gray magnetic
powder; with borax, both in oxidizing and reducing
flame, gives a deep-blue bead.
Tin (oxide) B B, in the oxidizing flame, presents a
dirty-yellow color; with carbonate of soda, in reducing
flame, on charcoal, reduces to metal; with borax, forms a
clear glass.
Lead (oxide) B B, in oxidizing flame turns first blue,
then fuses to a glass of orange color; with carbonate of
soda, on charcoal, in the reducing flame, reduces to metal;
with borax, forms glass yellow while hot, colorless when
cold.




EXAMINATION OF MINERALS.           85
Nickle (oxide) B B, infusible alone; in the oxidizing
flame, with borax, forms an orange-red globule which becomes nearly colorless on cooling; in the reducing flame,
on charcoal, the bead becomes gray; in the reducing
flame, with soda, on charcoal, reduces to a magnetic
powder.
Zinc (oxide) B B, in the oxidizing flame, exhibits a
whitish-green color; while hot, this oxide is slightly yellow-when cold, is white; with borax, forms glass which
in an intermittent flame becomes milky; in the reducing
flame, on charcoal, reduces to metal, which readily sublimes.
Iron (pre-oxide) B B, in the oxidizing flame, is unchanged; in the reducing flame, blackens and becomes
magnetic; with borax, in the oxidizing flame, forms glass
bright-red while hot, pale dirty-red when cold; in the
reducing flame, forms glass varying from bottle-green to
black-green; with carbonate of soda, on charcoal, reduces to metal as a dark magnetic powder.
iracznganese (oxide) infusible alone, becomes brown by
heat; with borax, in the oxidizing flame, much oxide
employed, the glass is black; little oxide employed, the
glass is of an amethyst color-in the reducing flame, and
on charcoal, this latter globule becomes colorless and so
remains if quickly cooled; with soda, in the oxidizing
flame and on platinum foil, forms an opaque green glass.
Silver (oxide) B B, with borax, in oxidizing flame,
forms a white opaque glass; in reducing flame, with carbonate of soda, readily reduces to metal.




86         QUARTZ OPERATOR S HAND-BOOK.
Gold (metal) B B, with carbonate of soda, in the reducing flame, readily fuses; the most appropriate test is
by cupellation.
Tellurium (oxide) B B, colors the flame green, fuses
and sublimes; with borax, in the oxidizing flame, forms
a colorless glass; in the reducing flame, the glass becomes gray; its behavior with carbonate of soda is
similar as with borax; on charcoal, readily reduces to
metal.
Soda (oxide of sodium) B B, colors the flame deepyellow.




BEHAVIOR OF SOLUTIONS OF METALLIC
OXIDES WITH REAGENTS.
ZINC (oxIDE).
Potassa and Ammonia, in neutral solutions, give white
gelatinous precipitate, readily soluble in an excess of the
precipitants.
Oxalic Acid occasions precipitates which are soluble in
acids and in fixed alkalies..Ferrocyanide of Potassium produces a white gelatinous precipitate, insoluble in hydrochloric acid.
COBALT (oxrDE).
Potassa produces a blue precipitate, insoluble in an
excess of the precipitant, but soluble in carbonate of
ammonia; the precipitate becomes green by exposure to
the air, and dingy-red when boiled.
Alkaline Carbonates produce a red precipitate, which
upon being boiled becomes blue.
Ferrocyanide of Potassiumr gives a green precipitate
which gradually turns gray.
Cyanide of Potassium precipitates cyanide of cobalt
as a brownish-white precipitate from acid solutions, soluble in excess of the precipitant, and not again precipitated by acids.




88         QUARTZ OPERATOR'S HAND-BOOK.
IRON (PROTOXIDE).
Potassa and Ammnonia produce a fioculent precipitate
of hydrated protoxide of iron which at first is nearly
white, but which readily becomes colored by exposure to
the air.
Alkaline Carbonates produce a white carbonate, gradually becoming colored, though not so readily as the
oxide. It is soluble in sal-ammoniac, but a colored precipitate makes its appearance by exposure to the air.
Ferrocyanide of Potassium produces a white precipitate if the air be excluded; but by exposure to air, or
by contact with nitric acid or chlorine, it forms Prussianblue.
Phosphate of Soda produces a white precipitate, which
after a time becomes green.
IRON (sESQuIoxIDE).
Potassa and Ammonia produce a voluminous reddishbrown hydrate, insoluble in excess. The precipitation is
prevented by the presence of organic acids, sugar, etc.
Alkaline Carbonates throw down precipitates of rather
a lighter color.
Sulphocyanide of Potassium  changes the color of
neutral or acid solutions to a deep blood-red color, owing
to the formation of a soluble sulphocyanide of iron.
This is the most unerring test, as it will detect the slightest trace of iron, even in the most dilute solution.
Phosphate of Soda produces a white precipitate, which




BEHAVIOR OF SOLUTIONS, ETc.         89
becomes brown, and finally dissolves on the addition of
ammonia.
MANGANESE (oxmIe).
Ferrocyanide of Potassium  produces a pale-red precipitate, soluble in free acids.
Ferricyanide of Potassium gives a brown precipitate,
insoluble in free acids.
Phosphate of Soda produces a white preciiteate, persistent in the air.
LEAD (oxmDE).
Potassa and Ammonia produce white precipitates,
soluble in a great excess of potassa, but insoluble in
ammonia.
Alkaline Carbonates produce white precipitates, soluble in potassa.
Phosphate of Soda occasions a White precipitate, soluble in potassa.
Ozalic Acid produces in neutral solutions a white precipitate.
Hfydrochloric Acid and Soluble Chlorides produce a
heavy white precipitate, soluble in boiling water, out of
which it separates, on cooling, in brilliant crystals. This
precipitate is soluble in potassa.
Sulphuric Acid and Soluble Sulphates produce:a white
precipitate, sparingly soluble in dilute acids, but soluble
in solution of potassa, and assuming a black color when
moistened with hydrosulphuret of ammonia.




90         QUARTZ OPERATOR'S HAND-BOOK.
SILVER (oxrDE).
Potassa and Ammonia produce a light-brown precipitate, readily soluble in ammonia; ammoniacal salts prevent precipitation by potassa.
Carbonated Alkalies produce a white precipitate, soluble in carbonate of ammonia.
Phosphate of Soda produces, in neutral solutions, a
yellow precipitate, soluble in ammonia. Solution of ignited phosphate of soda gives a white precipitate.
Protosulphate of Iron produces a white precipitate,
consisting of metallic silver.
Hydrochloric Acid and the Soluble Chlorides produce
a white curdy precipitate, even in exceedingly dilute
solutions. This precipitate becomes violet, and finally
black, without, however, suffering decomposition by exposure to light. It is insoluble in diluted acids, but
readily soluble in ammonia. When heated it fuses, without decomposition, into a horny mass.
A Bar of Metallic Zinc precipitates silver from its
solution, in the metallic state.
MERCURY (oxmrE).
Potassa produces a yellow precipitate, insoluble in
excess. If an insufficient quantity of the alkali be
added, the precipitate is reddish brown. The presence
of ammoniacal salts gives a white precipitate.
Carbonate of Ammonia produces a white precipitate.
Phosphate of Soda produces a white precipitate.




BEHAVIOR OF SOLUTIONS, ETC.         91
PFerrocyanide of Potassium  produces a white precip.
itate, which eventually becomes blue, owing to the
formation of Prussian blue.
Ferricyanide of Potassium produces, in solutions of
nitrate and sulphate, a yellow precipitate; in solutions
of the chloride, none.
Iodide of Potassium produces a cinnabar red precipitate, soluble in excess. It crystallizes out of a hot
solution in magnificent crimson spangles.
BISMUTH (oxmDE).
Potassa and Ammonia produce a white precipitate,
insoluble in excess.
-Alkaline Carbonates and Phosphate of Soda produce
white precipitates.
Ferrocyanide of Potassium occasions a white precipitate, insoluble in hydrochloric acid.
Ferricyanide of Potassium  produces a light-yellow
precipitate, soluble in hydrochloric acid.
Iodide of Potassium produces a brown precipitate,
readily soluble in excess.
COPPER (OXIDE).
Potassa produces a voluminous blue precipitate, which,
by boiling, loses water and becomes black
Ammonia, added in small quantities, produces a green
basic salt, which dissolves in excess, forming a fine blue
solution. In this solution potassa produces in the cold,




-92       QUARTZ OPERATOR'IS IAND-BO()K.
after a time, a blue precipitate, which, by boiling, be.
comes black.
Carbonate of Potassa produces a greenish-blue precipitate of basic carbonate of copper, which, by boiling,
is converted into black oxide.
Phosphate of Soda produces a greenish-white precipitate, soluble in ammonia, forming a blue solution.
Ferrocyanide of Potassium  produces, even in very
dilute solutions, a chocolate brown precipitate, insoluble
in dilute acids, but decomposed by potassa. This is a
very delicate test.
ierricyanide of Potassium produces a yellowish-green
precipitate, insoluble in dilute acids.
Cynanide of Potassium produces a yellowish-green
cyanide, soluble in excess of cyanide of potassium..Metallic Iron, when introduced into solutions of oxide
of copper, becomes covered with a deposit of reduced
copper.
ANTIMONY (oxnDE).
Potassa and Ammonia produce a white precipitate,
partially soluble in excess of the reagent.
Alkaline Carbonates and Phosphate of Soda behave
in a similar manner.
Mletallic Zinc throws down metallic antimony as a
black powder; if nitric acid be present the sesquioxide is
precipitated at the same time.
TIN (oxmnE).
Potassa, Ammonia and their carbonates produce a




BEHAVIOR OF SOLUTIONS, ETC.         93
white precipitate, soluble in potassa but not in ammonia;
by repose, and more rapidly when boiled, the solution is
decomposed-metallic tin, peroxide of tin and potassa
being formed.
Phosphate of Soda produces a white precipitate.
Ferrocyanide of Potassium gives a white gelatinous
precipitate.
Ferricyanide of Potassium occasions a white precipitate, soluble in hydrochloric acid.
A Bar of Jetallic Zinc precipitates tin in small grayish-white metallic spangles.
Chloride of Gold produces a purple precipitate, a mixture probably of peroxide of tin and metallic gold (purple of Cassius), insoluble in hydrochloric acid.
PLATINUM (PEROXIDE).
Potassa produces a yellow crystalline precipitate, consisting of the double chloride of platinum and potassium;
the addition of hydrochloric acid favors its formation;
it is insoluble in acids, but dissolves with the aid of heat
in potassa; it is very slightly soluble in water, and insoluble in strong alcohol.
Subnitrate of Mercury produces a yellowish-red precipitate.
Chloride of Tin, in presence of free hydrochloric acid,
communicates to solutions of bi-chloride of platinum a
deep red-brown color, without producing any precipitate.
Platinum soluble in aqua-regia.




94        BQUARTZ OPERATOR'S HAND-BOOK.
GOLD (PEROXNE).
Potassa (in heated solutions), after a time produces an
inconsiderable reddish-brown precipitate, consisting of
teroxide of gold mixed with terchloride of gold and
potassa.
Ammonia produces a yellow precipitate (aurate of
ammonia or fulminating gold).
Ferrocyanide of Potassium communicates to solution
of gold an emerald-green color.
Protosulphate of Iron produces in concentrated solutions an immediate dark-brown precipitate of metallic
gold. In dilute solutions a blue coloring is first perceived, followed by a brown-colored precipitate.
Oxalic Acid produces a precipitate of metallic gold.
Protochloride of Tin, to which a drop of nitric acid has
been added, communicates a reddish purple color to very
dilute solutions; in concentrated solutions a red-purple
precipitate (purple of Cassius) is formed.
A Bar of Metallic Zinc precipitates metallic gold in
the form of a brown coating.
Gold is soluble in aqua-regia.
TELLUROUS ACID.
The caustic alkalies and their carbonates produce a
white precipitate, soluble readily in potassa, and soluble
in alkaline carbonates.
Sulphurous Acids, Alkaline, Sulphites, and Metallic
Zinc, produce a black precipitate of metallic tellurium.




BEHAVIOR OF SOLUTIONS, ETC.          95
Protochloride of Tin and Protosulphate of Iron pro.
duce a black powder, which, on being rubbed, assumes a
metallic lustre.
Tellurium is soluble in nitric acid.
BLACK FLUX.
Black Fiux is prepared by introducing gradually in
small quantities into a crucible heated to a very dull
redness, a mixture of either two parts of cream of tartar
and one of nitre, or equal parts of cream of tartar and
nitre.
WHITE FLUX.
White Flux is similarly prepared to Black Flux, except
that the mixture consists of one part of cream of tartar
and two parts of nitre.




BLOW-PIPE.
The Blow-pipe is an instrument used for directing, by
a current of air, the flame of a lamp or candle upon a
mineral substance to fuse or oxidize it. The flame consists essentially of two parts-the "oxidizing" and "reducing." 1st. The "oxidizing" part is the outer and
slightly luminous flame; 2d. The " reducing " part, which
is hottest, is the inner blue flame.
The " reagents" mostly used in making blow-pipe tests
are charcoal, carbonate of soda, cyanide of potassium, and
borax. Black Flux and White Flux are much employed
in assaying.
Cacution.-Cyanide of potassium is a very dangerous
flux.  Its compound with a "nitrate" or "chlorate"
explodes with great violence.
Charcoal performs the part of a cupel as well as that
of a reagent. The best charcoal is made of young soft
wood.
The "cupel," or" support," consists of a sound piece of
coal, sawed or broken lengthwise, having a small cavity
made in its plane side near the edge, to hold the substance to be tested. The borax is prepared by being
melted or vitrified, and pulverized.
A. —Blowpipe Assays of Silver Ores containing Sulphur and Arsenic:
1st. Roast the pulverized ore within a shallow cavity




BLOW-PIPE.                   97
on the coal support. To do this, direct by the blowpipe the oxidizing flame, that is the extreme point of the
outer flame, upon the powdered ore; turn the specimen
occasionally so as to expose all of its parts to oxidation.
Let the blast at first be gentle, then increased and continued till the sulphurous odors cease.
2d. Pulverize the roasted ore, and put it upon the
charcoal within a prepared cavity; cover it over with
carbonate of soda, and direct upon it the reducing flame,
that is, the inner blue flame; let the blast at first be
gentle, and chiefly employed in fusing and bringing
together all parts of the flux, then increase the blast,
shaking the support or coal, so as to gather the metal in
one globule, which cool and extract from the slag.
3d. Cupel the button thus obtained, adding to it three
parts of lead in a boneash cupel. To do this, employ
the oxidizing flame by using a very gentle blast. Cool,
weigh the button, and compare its weight with that of
the original ore.
B.-Place within the cavity, on the charcoal, a mixture
of:
Powdered ore, (not necessarily roasted).....    1 part
Borax-glass (pulverized)................. 1 part
Lead: (Litharge preferable when earthy substances are present; and then it is also
advisable to make an addition of carbonate of potash and glass).............. 3 parts
and direct upon it the reducing flame till all the metal is
5




98         QUARTZ OPERATOR'S HAND-BOOK.
gathered into one button. Let the blast at first be gentle and chiefly directed upon the borax, then increased
and continued till the object is attained. Extract and
cupel the button as in example A.. —.Blo-2pipe Assay of Horn Silver. Place within the
cavity, on the charcoal, a mixture of:
Horn Silver (chloride of Silver)........... 1 part
Carbonate of soda (in excess)............. 3 parts
and reduce in the inner blue flame to a button, etc.




ASSAY.
Assays are three kinds-JMechanical, Dry, and Humid.
MECHANICAL ASSAYS.
Mechanical Assays consist in washing, or otherwise
freeing, without the aid of chemical agents, the metallic
substances from sand and other impurities. "Panning
out," or separating the gangue (earthy matter) from the
metallic substances by washing in common mining pans,
also winnowing, as practiced on rich dry sands are
familiar examples of mechanical assays and require no
explanations-the former of which often furnishes safer
and more practical data for extensive operations, especially in gold mining, than either the dry or humid way.
DRY WAY OF ASSAY.
The' dry" way of assaying usually requires the addition of fluxes to the ores to facilitate their reduction,
and separate the metals so reduced from the gangues.
Assay of Galena, or Ores of Lead containing Suzlphur.-Introduce into an earthen crucible in the following order:
Powdered Ore........................ 10 parts
Iron in strips or plates.............   1 to 3 parts
Black Flux...................... 30 parts




100        QUARTZ OPERATOR'S IHAND-BOOK.
Place upon the black flux a thick layer of salt, and on
this a piece of charcoal. Put an earthen cover on the
crucible, and fuse its contents, letting the temperature,
at first low, be gradually increased to bright red, and
continued at this degree about half an hour. Gently
rap the crucible, to settle all the metallic particles; then
cool the assay, and extract the button of lead.
Assay of Oxidized Ores of Lead.-Introduce into an
earthen crucible:
Powdered Ore......................... 10 parts
Carbonate of Soda..............  30 to 40 parts
Pulverized Charcoal.................... 3 parts
Iron, in strips or plates, in case any sulphur
may by present..................... 1 part
Cover with salt, etc., and conduct the assay as in the
preceding case.
Assay of Iron.-Fuse in a covered crucible about one
hour, a well triturated mixture of:
Powdered and Roasted Ore.............. 2 parts
Yliuor-Spar...............          part
Charcoal................................ 1 part
Common Salt, e. g. (for covering)......... 4 parts
Extract and weigh the button of cast iron thus obtained. Various other fluxes, as lime, clay, etc., may
be employed. The nature of the ore and its gangues
determine the kind and proportion of fluxes to be employed.
Assay of Copper Ores, containing no other metals
besides Iron and Copper. — Heat gradually at first, in an




ASSAY.                    101
earthen crucible, and afterwards increase the heat to
bright red, which continue fifteen minutes:
Powdered Ore..................... 1... 1 part
Black Flux.............................. 3 parts
Extract from the slag, and weigh the button of copper
thus obtained.
Assay of Copper Ores, containing Sulphur, but otherwise similar to the above. —Fuse in an earthen crucible,
at a dull red heat, equal parts of the powdered ore and
dried borax, extract from the slag the matte (crude copper) button, which pulverize; roast slowly in an earthen
crucible, and stir in the meantime with a steel rod till
sulphurous acid ceases to be evolved; then increase the
temperature to a white heat, which continue for several
minutes; next, mix in the same crucible:Roasted matte.......................... 1 part
Black Flux, from............... 3 to 4 parts
Cover the mixture with a layer of fused borax, and subject
it to a cherry heat for twenty minutes in a wind furnace;
then extract and weigh the button of copper.
Assay of Copper Ores containing Arsenic and various
other metals.-Obtain and pulverize the matte as in the
preceding case, then roast with it powdered charcoal till
the garlic odors of arsenic cease to be exhaled. Reduce
the matte thus obtained as in the last case with black
flux and borax. Cupel the button in a bone-ash cupel,
with pure lead. Throw a little borax-glass over the
globule when its rotation ceases and brightening occurs;
cool, and weigh the button of copper.




102         QUARTZ OPERATOR'S HAND-BOOK.
Assay of Gold or Silver or Gold or Silver Ores.-Fuse
in an earthen crucible:
Powdered Ore...................... 4 parts
Litharge...............................     4 parts
Black Flux.........................  3 parts
If the ores contain much oxide of lead, add only black
flux.  If the ores alre very rich in pyrites, add litharge
and nitre.  If the button obtained be an alloy, for instance, of gold, silver, copper and lead, make additions
to it of silver and lead, so that the prepared alloy shall
contain as near as may be ofGold.................................. I part
Silver................................. 3 parts
Lead, fronm....................... 12 to 16 parts
First fuse the lead in a bone-ash cupel, within a muffle;
then add the gold and silver inclosed in a piece of paper,
and continue the heat till the button brightens and
becomes tranquil; cool, and weigh the button. To separate the gold from the silver, called " parting of gold,"
anneal, beat the button into a thin plate, make it into a
roll, which is termed a " cornet." First heat this plate or
cornet in dilute nitric acid as long as the acid acts upon
it, then in concentrated nitric acid till all of the silver is,
dissolved. Thoroughly wash, dry and ignite the cornet.
The weight of silver is equal to the weight of the button
before parting, less that of the refined cornet.
REM:ARK. —Chloride of silver (horn silver) cannot be
decomposed by heat alone. It fuses at a temperature
of 500~ F. At a temperature of ebullition it is decom



ASSAY.                    103
posed by caustic potassa and soda, and if a little cane
sugar be added, the silver will be reduced to the metallic
state. It is also reduced to the metallic state when fused
with the alkalina and earthy carbonates. Thus one part
of the chloride of silver fused with two parts of carbonate of soda is reduced; also one part of the chloride of
silver with two parts of chalk and two parts of charcoal
reduces to the metallic state. Chloride of silver cannot
be decomposed by charcoal unless water be present; in
which case hydrochloric acid and carbonic oxide are
formed, and the silver liberated. Copper, tin and lead
reduce chloride of silver in the dry way. Mercury partially decomposes it, forming an amalgam of silver. The
chloride of silver, in a state of fusion, is very destructive
to earthen crucibles, scarcely less so than litharge.
HUMID WAY OF ASSAY.
Assay of Galena.-lst. Digest the powdered ore in
equal parts of nitric acid and pure water.-2d. Filter and
digest the residuum several hours with a strong solution
of carbonate of soda.-3d. Filter and digest the second
residuum in dilute nitric acid, and again filter.-4th.
Add either a solution of the sulphate of soda or sulphuric acid to the collected filtrates, as long as any precipitate takes place.-5th. Filter, then wash and dry the
residuum.-6th. Reduce the residuum with powdered
charcoal in an earthen crucible; cool, and weigh the button.




104:    QUARTZ OPERATOR S IAND-BOOK.
Assay of Colpper; Ores.-lst. Digest the powdered ore
in dilute nitro-muriatic acid.-2d. Filter the solution.3d. Add ammonia in excess to the filtrate. —4th. Filter
and wash residuum in ammonia.-Sth. Evaporate the
filtrate to dryness.-6th. Dissolve the dried filtrate in
muriatic acid. —7th. Add clean iron or zinc plates to the
solution much diluted.-Sth. Wash dry, and weigh the
copper precipitate.
The Swedish J ethod..-1st. Digest the thoroughly
roasted and powdered ore in concentrated muriatic acid,
stir well, and evaporate nearly to dryness.-2d. Add,
slowly, strong sulphuric acid till the odor of hydrochloric acid is no longer perceived; then heat till the
vapors of sulphuric acid begin to develop.-3d. Dilute
with distilled water, and keep the assay warm for some
time. -4th. Filter and wash the residuum in warm water.
-5th. Add and retain in the solution clean zinc plate
till no reddish tinge be given to a clean plate of iron dipped into the assay.-6th. Wash thoroughly the precipitate, dry at a temperature of 212~, and weigh the metal.
-7th. In case the precipitate be found partially oxidized,
complete the oxidation by heating the assay in an open
dish, and weigh the oxide of copper; thus-l100: 79.8::
weight of oxide: weight of copper.
Assay of Silver Ores.-lst. Digest the pulverized ore
in nitric acid.-2d. Add muriatic acid or solution of
common salt to the silver solution as long as any precipitate takes place.-3d. Filter and dry the residuum.4th. Reduce the dry residuum with carbonate of soda,




ASSAY.                   105
in an earthen crucible; then cool, and weigh the button
of silver.- Chloride of Silver, called, as found native,
"horn-silver," is completely insoluble in nitric acid, also
in water. —Ammonia, boiling solutions of the chlorides
of potassium, sodium, barium, strontium and calcium, also
cyanide of potassium, in solution, dissolve the chloride of
silver. Concentrated sulphuric acid slowly decomposes
it. Iron and zinc at the ordinary temperature decompose it, especially in presence of free muriatic acid.-Bromide of Silver in almost every respect resembles chloride of silver; it is, however, less soluble in ammonia.Iodide of Silver, found also native, is readily converted
into chloride of silver by muriatic acid.
Assay of Gold Ores. —lst. Digest the pulverized ores
in one part of nitric and four parts of hydrochloric acid.
-2d. Dilute, filter and evaporate the filtrate almost to
dryness, to expel excess of acid. —3d. Dilute the dried
filtrate in pure water; then boil the solution with a solution of sulphate of iron, which precipitates the gold as a
dark purple powder.-4th. Filter and heat the residuum
with hydrochloric acid.-5th. Filter, wash, dry and weigh
the gold powder. Oxalic acid, substituted for the sulphate
of iron, precipitates the gold in large flakes.
ASSAY OR ANALYSIS OF IRON ORES CONTAINING MANGANESE.
1st. Digest the roasted and pulverized ore in dilute
hydrochloric acid.-2d. Filter, wash residuum, and add




106        QUARTZ OPERATOR'S HAND-BOOK.
washings to the filtrate. —3d. Add muriate of barytes
until no further precipitation takes place.-4th. Filter,
wash, and add washings to the filtrate.-5th. Evaporate
the filtrate nearly to dryness, and to it add sufficient nitric
acid to transform the sulphate of iron to peroxide.-6th.
Add solution of caustic ammonia in excess to the solution.-7Tth. Filter and reduce the iron to the magnetic
state by heating the residuum with resin in an iron crucible; then cool and weigh. —8th. Precipitate the oxide
of manganese from the filtrate, by expelling the excess
of ammonia by heat.-When the ores contain much alumina or silex, flux them with three or four times their
weight of caustic potash, then digest in hydrochloric
acid, and proceed as above.
ASSAY OR ANALYSIS OF ORES CONTAINING
GOLD, SILVER, COPPER, LEAD, IRON
AND SULPHUR.
1st. Digest well the pulverized ore in nitric acid.2d. Filter, wash residuum (1), and add washings to filtrate (1). —3d. Add to filtrate (1) hydrochloric acid or
solution of common salt, which precipitates the silver as
a chloride. —4th. Filter, and digest residuum  (2) in
hydrochloric acid.-5th. Filter, wash residuum  (3) in
warm water, and to filtrate (3) with the washings add
filtrate (2).-6th. Reduce the chloride of silver with carbonate of soda by fusion, and weigh the button of silver.-7th. Add to filtrate (3), sulphate of soda in solua



ASSAY.                    107
tion, which precipitates the lead as a sulphate.-Sth. Filter
and add the residuum to residuum (1).-9th. Evaporate
filtrate (4) to any desirable extent.-10th. Add, in excess,
to concentrated filtrate (4) ammonia, which precipitates
sesquioxide of iron. —llth. Filter, wash residuum, and
add washings to filtrate (5).-12th. Dry and heat the
residuum in hydrogen gas within a glass tube as long as
any vapor of water is disengaged, then weigh the iron.
This powder, with glass as a flux at a high heat, becomes
a button of iron.-13th. Treat filtrate (5), after evaporating it to dryness with hydrochloric acid, then add
clean iron or zinc plates to the solution diluted. Wash,
dry, and weigh the copper precipitate.-14th. Treat residuum (1) first with a strong solution of carbonate of
soda, then with dilute nitric acid; and to the combined
filtrates add sulphuric acid, or a solution of the sulphate
of soda. Wash, dry, and reduce the precipitate with
powdered charcoal in an earthen crucible; then cool
and weigh the button of lead.-15th. Digest the last
residuum in nitro-muriatic acid; add chloride of sodium
in solution, filtrate, precipitate the gold from its solution
by the addition of sulphate of iron in solution; wash,
dry, and weigh the gold. —16th. If the gold may be alloyed with silver and copper, precipitate the copper from
the last filtrate by the addition of iron or zinc plates;
wash, dry, and add the weight of the precipitate to the
copper already obtained. Heat the residuary ore in a
strong solution of chloride of sodium, filter and precipitate the silver with a clean copper plate; wash, ignite




108       QUAPRTZ OPERATOR S HAND-BOOK.
and add the silver to that already obtained. —lth.
Burn off the sulphur and weigh residuary ore. The sum
of the weights of the gold, silver, copper, lead, iron and
calcined ore taken from the weight of the original ore
leaves the weight of the sulphur.




ROASTING.
Roasting is employed to dissipate the volatile parts of
the ore by heat, and is efected in H2eaps or in Furnaces.
HEAPS.
Alternate layers of fuel and ore, usually as it comes
from the mine, are heaped up to the depth of several
feet. The lowest or ground layer is of wood, arranged
by cross piling so as to afford a free circulation of air.
The upper layers may be of wood or coal. The ratio of
fuel in volume to that of ore varies from i to 6, to 1 to 18.
Fine ores, and those rich in sulphur, require less fuel
than coarse ores and those poor in sulphur. The fire is
kindled through vertical openings or chimneys, which
extend to the ground layer. These openings are closed
when the fuel has well taken fire. The roasting should
be slow and uniform in all parts of the heap. The heat
may be regulated by opening or closing the draft-holes
and chimneys. Several days, and even months, sometimes are required for roasting one heap. Ores similarly
piled with fuel are sometimes roasted in walled inclosures
provided with side openings.
FURNACES.
Furnaces are in great variety. Those mostly approved
for the roasting of ores, embracing also calcining and




110        QUARTZ OPERATOR'S HAND-BOOK.
chloridizing, are the reverberatory. The interior walls
of the furnace should be of the best fire brick, laid edgewise; the outer walls may be of common building brick
or stone. The furnace must be well tied with iron rods,
mnd carefully dried before being used.
Reverberatory EFrnace.-The Reverberatory Furnace
is constructed sometimes with one and sometimes with
two hearths or soles, one above the other. In the
"6 double-hearth " furnace, in the treatment of silver ores,
the "roasting" and "sulphatization" are effected on the
upper sole, and the "calcining" and " chlorodizing " on
the lower. The ore pulverized fine is charged upon the
upper sole to the depth of two to four inches, and is kept
well stirred during the "roasting."  The heat should be
at a low temperature, not exceeding brown or dull red.
The access of air should be free. A small jet of steam
let into the furnace assists in regulating the temperature,
and also facilitates oxidiation. The addition of powdered
charcoal in small quantities may be made to advantage
when the ores contain arsenic. If the ores are poor in
sulphur, add from two to three per cent. of the sulphate of
iron. The first operation of " roasting" and " sulphatizing " is accomplished in four or five hours. Then, through
an opening in the upper hearth, the ore is let fall upon
the lower, where it is heated for some time at a temperature not much higher than that mentioned above. The
heat is then gradually increased to cherry-red, at which
it is kept during the time required for " calcining " and' chloridizing."  The heat should never exceed bright




ROASTING.                   111
red. The ore is frequently stirred. WVhen calcination is
complete, a mixture of common salt, melted and pulverized, and seven parts of cold calcined ore are added to the
hot ore, estimated at fifteen parts, and quickly and thoroughly mixed'with it by stirring.  Calcination is usually
effected in four or five hours, and chlorination in fifteen
or twenty minutes.




S1MELTING.
Smelting is a process by which ores are reduced tc
the metallic state. It is performed in furnaces of which
there are several kinds. The "Backwoods hearth," or
"low' furnace, without artificial draught, also the
" Scotch and American hearths," or " low-blast " furnaces,
are employed on some ores, especially those rich in galena. The furnaces mostly approved for smelting purposes are the "Cupola" and the "Reverberatory," already mentioned under the head of" roasting." Each of
these is subject to various modifications in size and form
to meet the requirements of the nature of the ore, and of
local causes.
The Cupola, or "'high-blast" furnace, has a vertical
opening of greater height than breadth. This opening or
chimney-like shaft in a furnace of medium size is about
fifteen feet high, and has an area through its greatest
horizontal section of nearly twelve square feet: this
section is usually rectangular. However, in the Castilian furnace it is circular, and in the MacKenzie patent
furnace, very favorably known among practical furnacemen, it is quite eliptical. The blast, or a strong current
of air, is forced into the lower part of the shaft through
one or more tongues. The feed-opening is several feet
above the bottom. The ore fed into the "Cupola" furnace with the fuel is in contact with it, and subject to
the direct action of combustion. The flames, as they




SMELTING.                  113
rise, impart much of their heat to the ore, arranged in
layers one above the other, and finally pass off at a temperature far below that of the flames from the " Reverberatory." The " Cupola," compared with the "Reverberatory," as to first cost, expense for fuel, manipulating
and repairs is the more economical; but as to results,
especially in the treatment of rich ores containing little
or no quartz, the " Reverberatory" has the preference.
In smelting operations, as heat alone is frequently insufficient to induce the necessary chemical changes, fluxes
are employed. These are substances having an affinity
for some portion of the material under treatment, and
either effect its volatilization or form with it a fusible
compound or slag. This slag, lighter than the metal, is
often separated from it, either by being drawn off from
the surface, or suffered to remain until the metal is drawn
from  underneath. The flux to be employed depends
upon local causes and upon the nature of the ores and
gangues to be operated on.
Quartz, constituting the gangue of the ore, carbonate
of soda, lime, and the oxides of the base metals may be
employed as fluxes. The gangue, consisting of the different earths and the oxides of base metals, carbonate of
soda, litharge, and quartz may be used. The ores containing much sulphide may have as fluxes, carbonate of
soda, lime, metallic iron and litharge.  Granulated lead,
lead ore and litharge may be regarded fluxes for gold and
silver. The fluxes of most general use are carbonate of
soda, limestone or lime, litharge, iron and fluor-spar.




GOLD.
Gold occurs in nature chiefly in the form of alloys, the
most important of which is "native" gold (so called),
consisting of gold, silver, and small quantities of copper,
iron, and other metals. Gold is found alloyed with
rhodium and paladium; amalgamated with mercury,
and occasionally combined with tellurium in the form of
an ore, the telluride of gold.
TREATMENT OF ORE CONTAINING GOLD.
The treatment of ore containing gold is effected by
three distinct systems-Smelting, Amnalgamation, and
Chlorination.
BY SMELTING.
The method by smelting in most cases is identical with
that in the treatment of silver ores, to which reference
is here made.
_FPller's Lead Process.-An air-tight vessel is partly
filled with lead kept in a melted state by a fire below.
The pulverized ore is made to pass down a central pipe
or cylinder into the lead, through which it passes, and
then rises into the chamber, floats on the surface of the
metal, and is removed through a side opening. The gold
is supposed to be thoroughly amalgamated or alloyed




GOLD.                    115
with the lead, from, which it is afterwards obtained by
cupellation.
BY AMALGAMATION.
Arastra.-lst. The arastra is a machine employed for
the reduction of ores and the amalgamation of the precious metals. It is composed of a stone-paved bottom
from six to twenty feet in diameter, wooden-rim two feet
and upwards in height, and an upright wooden shaft
having'two or more horizontal arms, to which are attached, by chains, the "'mullers," consisting of large
blocks of granite.-2d. The ore in pieces not larger
than hens' eggs is introduced into the machine, and the
muller set revolving at'the rate of four to seven feet a
second. As the reduction proceeds, quicksilver firom
time to time is sprinkled through a cloth or other porous
substance into the mass under treatment.-3d. When the
reduction and amalgamation is completed, the " slime" or
" gangue " is washed off, the amalgam is " cleaned up,"
"squeezed " and " retorted."
Pcan Process. —lst. The rock as it comes from  the
mines is crushed wet by stamps to a fine granular state,
and run into large tanks.-2d. Charges of the reduced
ore, with sufficient water to form  a thin paste, are
thoroughly ground in iron pans. As gold in rock exists
almost without exception in a metallic state, friction
with a moderate degree of heat is usually found quite
sufficient to fit it for amalgamation. Heat, however, is
often employed in the amalgamation of gold, and for the




11 ]. 6    QUARTZ OPERATOR S HAND-BOOK.
most part in the form of steam. The steam is let in
some cases direct into the charge in the pan, but is
usually applied in steam chambers underneath the pulp.
the latter method is preferable to the former. Exhaust;team, charged with oily matter, is detrimental to amalgamation, and hence should not be introduced into the
pulp. It is the' exhaust steam that is commonly employed for heating the ore under treatment. That a
high degree of heat facilitates the amalgamation of gold
is not without its advocates. The results, however, of
an extended series of experiments made by several expert amalgamators in California were not in favor of its
application.-3d. Quicksilver is ordinarily added to the
pulp as the pans commence running. To avoid grinding
the quicksilver excessively, the addition is sometimes
made with the muller slightly raised, after the reduction
of the ores.-4th. The charge is then drawn off and
washed, leaving the amalgam in the separators.-Sth.
The proportions usually observed, for instance in the
Wheeler & Randall Grinders and Amalgamators, are,
ore to the charge (4 feet muller), 1,500 pounds; quicksilver to the charge of ore, 100 pounds; revolutions of
muller, 60 to 75; time of reducing, usually about 3
hours.
As gold-bearing rock is seldom found sufficiently rich
to render it advisable to treat the entire mass in pans,
the above method is subject to various modifications, of
which the following are a few: —lst. The heavier and
richer portions of the rock, as crushed, are concentrated




GOLD.                   117
by revolving-blankets, buddies, concentrators, or other
machinery, then pulverized and amalgamated in pans.2d. Amalgamation is commenced in the batteries during
the crushing operation, and is carried on through a
series of shaking tables, riffles, and copper plates. The
richer portions of the tailings are then concentrated and
treated in pans.-3d. Grinding and amalgamating are
effected in pans while the reduced ores are flowing continuously through them. —4th. The sulphides or concentrated tailings are roasted in a reverberatory furnace
before being ground and amalgamated.-5th. Thin layers of the concentrated sulphides or tailings are spread
in inclosures open to the sky, and allowed to remain a
long time, for instance a year. The tailings are occasionally turned with shovels, and the lumps broken so as to
expose as much surface as possible to the action of the
air. Common salt, mixed with the tailings, assist in their
oxidation. When thoroughly oxidized they are treated
in pans.
The process of amalgamation is not well adapted to
raw ores containing the compounds of sulphur, arsenic,
tellurium, bismuth, iron, lead, copper, antimony and zinc.
These substances not only cause a "sickening'" of the
quicksilver, but so tarnish or " coat" the gold as to ren
der amalgamation next to impossible. For the most part
such ores should be thoroughly roasted and the deleterious substances volatilized before attempting amalgamation; or in many cases it may perhaps be better to subject them to smelting.




118        QUARTZ OPERATOR'S IAND-BOOK.
Hagan's Process. —In this process, pyritous ores are
heated red hot in a tall furnace and subjected to the
action of a current of super-heated steam, obtained by
passing dry steam through a coil of pipe in the fire-place
on box below. It is claimed that the heated watery
vapor is decomposed, and that the oxygen and hydrogen
combine with the elements of the ore, converting the
sulphides into oxides with the liberation of the gold,
while the sulphur combines with the hydrogen, forming
sulphide of hydrogen, which is burned. The wasted ore
is reduced to a fine powder or slime, and subjected to
amalgamation. The reports are conflicting as to results.
BY CHLORINATION.
1st. Pulverized ores containing gold, having been well
roasted, cooled and moistened with water, are put into
closely-covered wooden cisterns whose bottoms are so
constructed that chlorine gas can permeate the mass
from underneath. The ore containing " lime " and " talc "
should be roasted with salt, as those substances are
highly detrimental to chlorination.-2d. Chlorine gas,
produced by heating sulphuric acid, peroxide of manganese and common salt in a leaden generator, is caused
to enter the cisterns at the bottom, through leaden pipes.
The chlorine gas should be forced through clean water,
to cleanse it of muriatic acid, which in several ways is
very injurious to the operation. The effect of the chlorine on the gold is to produce terchloride of gold.-3d.




GOLD.                     119
Pure water, after the chlorine has done its duty (which
takes from ten to fifteen hours), the covers of the dissolving cisterns being removed, is added sufficient to fill
the cisterns even with the ores. The effect of the water
is to dissolve the terchloride of gold; the solution is
then drawn off into glass vessels.-4th. Sulphate of Iron
in solution is used to precipitate the gold, which may
then be gathered, melted, and run into bars.




SILVER.
Silver occurs in nature under many forms, viz:
Native Silver.-Native Silver sometimes occurs almost
chemically pure, but often is in alloy with gold, copper
and other metals.
Antimonial Silver and Bismuth.-These alloys, owing
to their scarcity, are of but little commercial value.
Native Amalgam.-The composition of several known
varieties of native amalgam is-silver, 34.8; mercury,
65.2; silver, 26.25; mercury, 73.75; silver, 86.49; mercury, 13.51.
ORES OF SILVER.
The ores yielding the greater part of the entire annual
product of silver, and hence the most important, are:
Silver Glance.-This ore, known also as Vitreous Silver, Sulphide of Silver, is, on account of its abundance
and richness, the first in importance. Its composition
is-silver, 87.04; sulphur, 12.96.
Stephanite.-This ore, known as Brittle Silver Ore,
Black Silver, ranks second in importance. It is composed of-silver, 70.4; antimony, 14.0; sulphur, 15.6.
Pyrargyrite.-This ore, its name implying ruby silver,
is usually black; sometimes, however, approaching cochineal-red. Its composition is-silver, 58.98; antimony,
23.46; sulphur, 17.56.




s LvE R.                 121
Chlorige of Silver. —This: ore, known as Horn Silver,
Muriate of Silver, when found in large quantities, as in
Nevada, is very valuable as an ore. It has, however, not
been found to extend downward in mineral veins to any
considerable depth, but to have been succeeded by stlphides, arsenides and compounds of antimony. Its hardness is but little above that of talc, often the same. Its
composition is-silver, 75.33; chloride, 24.67. Many
other ores of silver occur, but are comparatively of little
commercial importance. The following comprise nearly
or quite all the ores of silver known:
Silver Native —Usually found alloyed with copper,
gold, etc.
Silver Glance-Vitreous Silver, Sulphuret of Silver
(AgS), S12.96, Ag87.04, H=2-2.5, G-7.196-7.365.
iessite-Telluric Silver, AgTe=Te37.23, Ag62.77, H
52.-2.5, G=8.3 —8.9
_Nauzmannite-AgSe-Se27, Ag73, H-2.5, G=8.
Eucairite-Seleniuret of Silver and Copper, CuSe+
AgSe= (Cu,Ag) Se31.58, Cu25.26, Ag43.16.
Stromeyerite-Argentiferous Sulphuret of Copper, CuS
+AgS=(Cu,Ag) S=S15.92, Ag52.71, Cu30.95, H=2.5
-3, G=6.2.
Antimonial Silver —Antimoniate of Silver, Ag4Sb=
Sb23, Ag=-77, also AgSb=-Sb16, Ag83.4, H=3.5-4, G
-=9.44- 9.80.
Arsenic Silver —Consists of Arsenic, Iron, Antimony
and Silver.
Fklexible Silver Ore-Ferrosulphuret of Silver.




1~22       QUARTZ OPERATOR'S HAND-BOOK.
trnbergite, A;egS+:Fe2S=.S3421, Ag32.83, Fe3-2.96,
-I =1. —1,., G4.215.
lXiargyrite, AgS+ SbS3=S21.35, Sb42.79, Ag35.86.
Pyargyrite-Dark red Silver Ore, Ruby Silver, Black
Silver, 3AgS+t-SbS3-S17.56, Sb23.46, Ag58.98, 11=2.2.5, G=5.7 —5.9.
Proustite-Light red Silver Ore, 3AgS +AsS3 —-S19.46,
As15.16, Ag65.38, H-=2.-2.5, G=5.422 —5.560.
Frieslebenite-Antimonial Sulphuret of Silver (PbS +
SbS3) +2, (3Pb,AgS) + SbS3==S18.77, Sb27.72, Pb30, Ag
22.18, H-2.-2.5,  — 6.-6.4.
Polybasite, 9 (Ag, Cu) S +(Sb,As) S —S17.04, Sb5.09,
As3.74, Ag64.29, Cu9.93, H=2.-3, G=6.214.
Stephanite-Brittle Silver Ore, Brittle Silver Glance,
Black Silver, 6AgS +SbS3 —S15.6, Sb14, Ag70.4, H — 2.
-2.5, G=6.269.
Xanthokon (Yellow Powder) H —=2, G==4.2-4.3, 3
(AgS + AsSS) + 2      +(3AgS-AsS)=S21.36,  As13.49, Ag
64.18.
Bismuth Silver-Bismuth Silver Ore. Composition
variable:
Eg. Bi27, Pb33, Ag15, Fe4.3, Cu0.9, S16.3.
60.1  10.1              7.8    As-2.8
2Hiorn Silver-Muriate of Silver, Chloride of Silver,
AgC1-C124.67, Ag75.33, H=. — 1.5, G-5.552.
Iodic Silver-Iodite. Composition variable.
Bromic Silver —Bromite, AgBr —Br42, Ag58, H=l1.
-2 G=-5.8-6.




-SLVER.                   123JEmbolite, 2AgBr + 3AgCl-Ag (C1,Br)>=Aga66!.96, Br
19.84, C113.20, H-==2, G —5.79 —5.81.
Selbite-Carbonate of Silver, AgC= AgO84, C0O16;.
Very soft. Sometimes called Blue Silver.
TREATMENT OF SILVER. ORES.
The treatment of Silver ores. is effectedd by- three dis.
tinct systems, viz.:: Smelting, Solution and Amalgama,tion. Each of these systems: is. severally:subdivided, and.
subject to almost indefinite. modifications.
BY SMELTING.
A radical feature in nearly every method, of smeltilngsilver ores: is the employment of lead in one or more of
its forms. If lead in some form  does not occur in theore to be operated on, it has to be added. In connection
with the smelting of silver ores, among the more important properties to be observed of lead and its compounds
are as follows, to wit: —1st. The sulphide, oxide or sulphate of silver fused with lead, the silver is reduced to
the metallic state, and forms an alloy with the excess of
lead. —2d. The sulphate of silver. fused with the oxide or'
sulphate- of lead, argentiferous lead results. —3d. Lead
has much less affinity for the base metals than for silver.
— 4th. A fused alloy of lead and silver acted on by a
blast of air, the. lead becomes oxidized, while the silver
remains unchanged.-5th. In the furnace, the sulphide
or sub-sulphide of lead and the sulphate of lead react




124       QUARTZ OPERATOR'S HAND-BOOK.
upon each other and produce metallic lead, which takes
up the silver, if any be present.-6th. One part of sulphide of lead, and three parts of sulphate of lead, react
upon each other and produce litharge.-7th. Sulphide of
lead and metallic iron, copper, antimony or zinc in a state
of fusion react upon each other, and produce on one
hand metallic lead, and on the other the sulphide of iron,
etc. If the sulphide of lead at the same time contain the
sulphide of silver, the same reactions take place, and the
lead and silver enter into alloy, while the iron or other
of the metals named is converted into a sulphide. Iron,
it may be observed, is usually employed as a flux or
reagent. It seems proper here to remark that the treatment of an ore containing silver and gold, inseparable in
smelting, is not modified on account of the occurrence of
the latter metal.
IN REVERBERATORY FURNACE.
Corinthian Process.-lst. The ore, for example, argentiferous galena of pure quality, is roasted by a slowly:
increasing temperature until the sulphate thus produced
is to the sulphide in the proportion of their equivalents.
-2d. The temperature being increased and the charge
thoroughly stirred, the sulphide and sulphate of lead reacting upon each other produce metallic lead and sulphurous acid gas, of which the former flows from the furnace into vessels prepared for its reception, the latter
escapes by the chimney.-3d. In connection with the reduction of the metal is formed a subsulphide of lead.




SILVER.                   125
This and the sulphate of lead in the proportion of their
equivalents react upon each other and produce a further:
amount of lead.-4th. The roasting is continued until
litharge is finally formed by the reactions of one part of
sulphide and three parts: of sulphate of lead. Charcoal
is. then added, which reduces the litharge and sulphate
of lead in excess to the metallic state.-5th. The alloy, if
sufficiently rich in silver, is subjected to cupellation; but
if poor in silver, may well first be enriched by the Pattinson process.
IN CUPOLA FURNACE-CASE I.
Silesian Process.-lst. The raw ore, argentiferous galena, and iron-flux prepared by being broken into small
pieces and uniformly mixed, are so thrown with the fuel
into the furnace that they shall occupy the back of the
shaft while the fuel shall occupy the front.-2d. Sufficient
blast being applied to induce a gradual fusion, and the
reactions of the sulphur and iron together with oxygen
taking place, the furnace hearth becomes filled with the
rich, liberated lead, and floating slags. —3d. As occasion requires, the lead ready for cupelling is drawn off
through an aperture in the bottom of the furnace, and
the slags. through a more elevated opening. The richer
portions of the slags, or properly matte, composed of
the sulphide of iron and lead, with a little silver, are subjected to the further treatment of roasting and fusion.4th. The. proportions of a charge are as follows.: galena
in small fragments, 1QQ parta; cast: iron, 12. parts;




126        QUARTZ OPERATOR'S HAND-BOOK.
slag from iron forge, 14 parts; fuel (mineral coal), 126
parts.
IN CUPOLA FURNACE-CASE II.
cRammelsberg Process.-lst. The ores, argentiferous
galena, abounding in earthy and metallic impurities, are
roasted either in Reverberatory Furnaces or in Heaps in
the open air.-I-2 the Reverberactory Furzace: The roasting is conducted in the ordinary manner to the desired
extent of oxidation. The heat then being increased, the
furnace closed and the charge fused, the silicates of lead,
of lime, etc., are formed, which with the oxide, sulphate,
and sulphide of lead are drawn upon the floor of the
furnace, cooled and broken to sizes best suited to treatment in a cupola furnace, e.g., size of oranges. —In
Heaps: 1st. Ores abounding in the sulphides of iron,
zinc and copper being intimately mixed with galenaarranged in order of the sizes of the blocks, the largest
at the bottom, are piled several feet high upon a thick
layer of wood, and covered with pulverized roasted ore
which prevents the access of too much air. The sulphides constitute the greater portion of the fuel. From
four to six months are required for the first roasting of a
heap containing one hundred and fifty tons of ore. The
metallic products of the operation are subjected to a
second and third roasting, or rather to a succession of
roastings, until the sulphur and other volatile substances
are well dissipated.-2d. The charge consisting of
roasted ore, silicious slags, litharge. and fragments of old.




SILgEo.   -               127
cupels-all reduced to the size of hens' eggs and thoroughly mixed, are introduced with the fuel into the furnace. A strong blast applied, inducing fusion and the necessary chemical changes, the lead, matte and slangs sink
upon the hearth and are disposed of as in Case i. The
proportions of a charge are: roasted ore, 140 parts;
highly silicious slags, 40 parts; litharge, 1 to 2 parts.
IN CUPOLA FURNACE —CASE III.
lst. —Argentiferous cawbonate of lead, white lead ore,
is prepared for the furnace by being broken into small
pieces-or occurring as powder-by being made with
clay into orange-sized balls and dried. The charge consisting of the prepared ore, litharge, cupel bottoms, and
other fluxes suited to the gangues, is thrown with the
fuel into the furnace —the charge more on the side of
the back wall, and the fuel on the side of the front.-2d.
As the blast is let on, and the ore-mixture fused, the carbon of the fuel reduces the free oxides of lead; also
those in combination. The metallic lead and slags are
drawn off at proper intervals.-3d. The remunerative
portion of the carefully-sorted slags are returned for
fuision. The fumes collected in the condensing apparatus, and sometimes amounting to nearly half the lead
originally treated, are made into orange-sized balls, dried
and fused again. The lead obtained is either first treated
by the Pattinson process, or cupelled at once for its
silver.




128         QUARTZ OPERATOR'S. HAND-BOOK.
IN CUPOLA FURNACES.
Xlexican Process.-lst. The ore, composed chiefly of
the sulphide of silver', sulphide of iron and quartz, free
firom the compounds of lead, being intermixed with charcoal of half its weight, is roasted in walled inclosures
open to the sky. An equal amount of dry wood is sometimles used instead of charcoal, and the roasting effected
il circular kilns measuring on the inside four and a half
feet in diameter, and the same in height, built of sun-dried
blrick, and capable of holding, besides the fuel, about a
ton of ore each.-2d. The roasted ore and fluxes being.
well mixed are introduced with charcoal into the furnace
in the following proportions: roasted ore, 75 parts;
native carbonate of soda, 16 parts; lead slags, 16 parts;
cupel bottoms, 16 parts; matte of previous operations,
25 parts; litharge, 100 parts; charcoal, 50 to 75 parts.
As fusion takes place, the metal is dirawn off fiom time
to time and cast into ingots, ready for cupellation. The
matte that is gathered is returned to the- furnace as one
of the fluxes for succeeding charges of ore.
Pattinson Process. —lst. This process is founded on
these facts: If a melted alloy of silver and lead is stirred
while cooling slowly, crystals of lead form and sink,
which may be removed with a drainer. A large portion
of the lead may thus be separated from the silver.-2d.
Cast-iron pans, capable of holding about five tons. each,
provided with fire-places, are arranged in; a series, as A,
B, C, D, E, F, G, in a straight line.-3d. The metal of




SILVER.                  129
ores containing silver and lead as it comes from ordinary
smelting works, is melted, for instance, in pan D, and
then allowed to cool very slowly. The metal, while cooling, is stirred, especially near the edges of the pan, with
an iron bar. As soon as crystals form and sink to the
bottom they are taken out with an iron drainer raised to
a temperature somewhat higher than that of the metal
bath. From one-half to two-thirds of the charge is thus
removed to pan E, and the balance taken to pan C. Other
charges of D are similarly treated and disposed of.
The charges of C and E are treated and disposed of in
like manner, except that the crystals of E go to F, and
the balance to D, and the crystals of C go to ID, and the
balance to B. Thus after successive meltings and drainings, the alloys rich in silver pass to A, while the lead,
almost entirely deprived of silver, goes to G. The alloys
obtained in pan A are then subjected to cupellation.4th. The lead of an alloy treated by this process often
contains less than one dollar in silver to the ton. The
silver of the enriched alloy should not exceed six hundred dollars to the ton.
Parke Process.-lst. Lead containing silver is fused
in large cast-iron pots. Melted zinc is added and well
stirred in the alloy. The fire being withdrawn from
under the pot, the whole is left at rest for a short time.
-2d. The silver and zinc, separating from the lead, form
an alloy which is skimmed from the surface of the metalbath as long as it rises.-3d. The scum alloy containing
some lead is heated in a liquation retort. The silver and




130        QUARTZ OPERATOR'8- HAND-BOOK.
lead fuse, and to a great extent, flow; into prepared
moulds. The alloy thus run off is then cupelled; the alloy of zinc and silver remainin g in the retort are parltially
separated by distillation.  The silver thus obtained is
freed of its impurities by cupellation.-4th. Tile proportions are: charge of argentiferous lead to the pot, ftrom
6 to 7 tons; charge of zinc to the ounce of silver, by
estimation, 1.5 to 2 pounds; quantity of silver to the
ton of lead, 10 to 15 ounces; time of stirring alloy after
the addition of zinc, 10 to 15 hours; silver to ton of alloy prepared for cupellation, 1,000 ounces.
Liquation~ Process.-lst. This process is founded on
these facts: Lead and copper fused- together form an
alloy which, if rapidly cooled, maintains an intimate admixture, but, if slowly cooled, separates. An alloy of
lead and copper, slowly heated to near its point of fusion,
also separates; silver, if contained in the alloy, goes with
the lead. —2d. Either an alloy of copper or silver, or
matte (crude black copper, reduced, but not refilled fiom
sulphur and other impurities) containing silver, as it
comes from the smelting furnace, is melted with lead of
about four times its weight, in a cupola furnace, and
cast into plain circular plates which are suddenly cooled.
These plates, called s" Liquation Cakes," are arranged on
their edges with alternate layers of charcoal, in a liquation furnace. The charcoal is then ignited, and a degree
of heat produced somewhat below that of the fusing
point of copper. The lead and silver melt and flow into
a receiver, while the copper, in a porous state, retains the




SIVVER.                    131
forms of the original cakes.'If the -separation may have
been imperfect the cakes:are further treated by'being
raised to a higher degree of heat in the'sweating furnace.
The silver is then separated from the lead by cupellation.
BY SOLUTION.
Augtustin Process. — lst. This process is founded on the
solubility of chloride of:silver in a hot concentrated solution of common salt.-2d. The ores are crushed dry by
stamps, and pulverized in suitable mills.-3d. The roasting in:a reverberatory furnace is commenced at a low
temperature Iwith -a free access of air. By careful, uniform  roasting, at a dull red heat, the sulphates of the
various metals are produced. The heat is then increased
to cherry red, which decomposes the sulphates of iron
and:other base metals, but not the sulphate of silver.4th. Common salt, previously melted, pulverized iand
mixed with cold ore, is -added to the hot ore in the farnace and thoroughly mixed with it by-stirring.  The sulphate of silver is thus converted to chloride of silver —
5th. The apparatus for the humid operations consists of
a large heating reservoir, a series of dissolving tubs, two
large settling cisterns, four precipitating tubs to each
one of the dissolving tubs, and two large receptacles,
arranged in the order here given, on descending steps.
The dissolving and precipitating tubs are nearly cylindrical. They are provided with filters made of small
sticks and straw,covered witth oth.  A vertical parti




132        QUARTZ OPERATORIS HAND-BOOK.
tion resting on the filter divides each tub into two unequal compartments.-6th. The chloridized ore being put
into the larger compartments of the dissolving tubs, sufficient of the hot salt solution from the heating reservoir
above, to completely immerse the ore, is let into the tubs;
they are then left at rest one hour. The dischargecocks of the heating reservoir and tubs then being
opened, the hot salt solution is filtered through the contents of the tubs, and run off from the smaller compartments, at openings at first above the level of the ore,
afterwards at openings near the bottom of the tubs, into
the settling cisterns, until a test with clean copper shows,
no trace of silver in the filtered solution. —7th. Copper
(copper cement) is put into:each of the upper two precipitating tubs in the several series of four, and iron
(wrought scrap-iron) into each of the lower two. The
chloride solution from the settling cisterns is then slowly
filtered through the several series of precipitating tubs,
and the filtered solution run into the large receptacles
below. The silver is precipitated by the copper in the
upper tubs, and the copper in solution, if contained by
the ore at first, is precipitated by the iron in the lower
tubs. The silver is taken twice a week from the precipitating tubs and refined. The filtered solution in the
receptacles is pumped into the heating reservoir and
used again.-8th. The proportions usually observed, are:
ore before roasting should contain of sulphur not less
than 20 per cent.; charge of ore to the furnace, for roasting and calcining, 500 pounds;: charge of melted -salt, 35




SILVER.                   133
pounds; roasted ore, cold, mixed with salt, 220 pounds;
time, roasting on upper sole of furnace, 4 to 41 hours;
calcining on lower sole of furnace, 4 to 41 hours; time
of chloridizing, front 15 to 20 minutes; degrees of heat
of salt solution, 131~ Fahr.; time of dissolving and precipitating, 20 to 24 hours; solution of salt, run through each
tub to one thousand pounds of ore, 200 to 250 cubit ft.;
depth of copper in precipitating tubs, about 6 inches;
depth of iron in precipitating tubs (if the ore contains
copper worth saving), 6 inches.
REMARK.-Zinc, antimony and arsenic are detrimental
to the Augustin and Ziervogel processes.
Ziervoyel Process. —lst. This process is founded on the
solubility of sulphate of silver in hot water.-2d. The
ore, as in the Augustin process, having been thoroughly
pulverized, is carefully roasted and calcined till the sulphates of iron and other base metals are completely
decomposed, but none of the sulphate of silver, which is
much more obstinate. When small quantities of the
roasted ore thrown hot into water give only a very slight
blue color, the calcination is regarded complete.- 3d.
The sulphatized ore is treated in all respects the same
as the chloridized ore in the Augustin process, except
that pure water is employed instead of solution of salt.
The degree of heat of the water for dissolving should
be 1490 Fahr.
Von Patera's Process.-lst. In this process the ores
are thoroughly pulverized and chloridized by roasting
with common salt.-2d. Hot water, to dissolve the chlo



134        QUARTZ OPERATOR'S HAND-BOOK.
rides of various base metals, is filtered through the chlo,
ridized ores put in tubs similar to the dissolving tubs in
the Augustin process. The ores are then cooled and
transferred to similar but smaller tubs. —3d. Hyposulphite of soda, in cold solution, is then filtered through the
ores and run into precipitating tubs until all the chloride
of silver is completely dissolved.-4th. Polysulphide of
sodium, sufficient to produce a neutral liquor, is then
added, which precipitates the silver as a sulphide in sacks
fitted to the inside of the tubs. (Polysulphide of sodium
is produced by fusing common soda ash with sulphur, and
subsequently boiling the product, dissolved in water, with
sulphur in a finely divided state.) This neutral liquor,
the hyposulphite of soda, is preserved for lixiviating purposes.-5th. The sulphide of silver thus obtained, after
being washed in warm water, pressed and dried, is heated
under muffles, with free access of air, till nearly all the
sulphur is expelled. The metallic silver is then refined.
Freiberg Process, by Sulphuric Acid. —st. The matte,
impure copper containing silver, as it comes from the
furnace is finely pulverized, thoroughly roasted and chloridized as in the Augustin process.-2d. The chloridized
matte, put into tubs, is subjected to the action of hot sulphuric acid. The copper, with what iron may be present,
is dissolved, while the silver is but slightly affected. —3d.
The solution of the sulphate of copper is drawn off into
vats and crystallized.-4th. The undissolved remainder,
containing the silver, is smelted with lead and cupelled.
Bammesburg Process, by Sulphuric Acid.-lst. Gran



SILVER.                   135
ulated copper containing silver placed in tubs is subjected, in connection with abundance of air, to the action
of hot sulphuric acid trickled over it. —2d. The copper,
thus converted into the sulphate of copper, runs off in solution through a series of troughs, in which it is deposited
in the form of rough crystals. This liquor is returned,
heated, and again trickled through the material under
treatment.-3d. The rough crystallized salt is washed,
dissolved in the hot molten liquor of previous process,
run into vats, and recrystallized. —4th. The residuum in
the dissolving tubs is smelted with lead and cupelled for
its silver.
BY AMALGAMATION.
Patio Process. —lst. Patio signifies a yard. For amalgamating purposes, the floor of the yard is made level,
paved with brick or granite blocks, surrounded by high
walls and usually left open to the sky. On this floor,
circular batches of silver ore, reduced to an impalpable
paste by stamps and arastras, or other machinery, are
spread to the depth of seven to twelve inches, and inclosed by low close curbs.-2d. Salt (chloride of sodium), varying in quantity according to its quality and the
richness of the ore, is well mixed with the pulp by treading it with horses, mules or oxen, and turning it with
shovels. The effect of the salt is to desulphurize the
sulphides and produce chloride of silver. The batch is
then left one entire day. —3d. Magistral, that is roasted
and pulverized copper pyrites, varying in quantity with




136        QUARTZ OPERATOR'S HAND-BOOK.
its quality, the richness of the ores and season, is well
mixed with the pulp after it has been subjected to the
treading and turning operation one hour. The ultimate
effect of the magistral is to revive the silver by depriving it of chlorine.-4th. Quicksilver is added, usually
in three charges to the mass, by being sprinkled in minute particles through cloth or other porous substance.
After the addition of the first charge of quicksilver, the
batch is thoroughly mixed, thrown into heaps of about
one ton each, smoothed, and left at rest one whole day.
The treading, turning and heaping operation is performed
every other day, occupying five or six hours, and is found
much more effective in a morning than an evening. The
second charge of quicksilver is added and similarly
treated, when it is ascertained by washing a small quantity of the mixture that the first has been well incorporated. After the second charge has performed its work,
the third charge is added to take up any stray particles
of silver, and to fit the amalgam better for separation.5th. Lime is added to cool, and magistral to heat the
mass, according as it may be too hot or too cold. Too
much heat is indicated by the quicksilver becoming
extremely divided and of a dark color, with occassional
brown spots upon its surface; too little heat is indicated by the quicksilver retaining its natural color and
fluidity. A proper degree of heat is indicated by the
amalgam being of a grayish white color, and yielding
readily to a slight pressure. —6th. The proportions to
the ton of ore valued at fifty dollars are: salt, of good




SILVER.                   137
quality, 80 pounds; magistral (containing ten per cent.
of the sulphate of copper), in summer, 20 pounds-in
winter, 10 pounds; quicksilver (first charge) 14 pounds,
(second charge) 5 pounds, (third charge) 7 pounds;
lime, more or less (see Sec. 5), 15 pounds. An excess of
magistral, quicksilver, or lime is injurious; an excess
of salt causes a loss of quicksilver, but is not otherwise
detrimental. The time employed in treating a batch of
ore varies from twelve to sixty days. Light and good
weather greatly facilitates operations.-7th. The separation is accomplished by washing the pulp or mixture
with abundance of water in a large deep circular vessel,
similar in principle to the common settler or separator,
and causing the lighter portions of the mass to flow
slowly off until the amalgam is gathered by itself, when
it is taken to the refining works.
Preiberg Process.-lst. This process takes its name
from Freiberg, a place in Germany where it was first
practiced. The ores, if possible, are assorted so as to
contain not less than twenty-five per cent. of sulphides.
When they contain less, the sulphate of iron is added to
make up the deficiency; when more, a sufficient quantity
of the richest in sulphides is roasted without sea-salt to
make good the ratio. The ores are crushed dry.-2d.
Salt (chloride of sodium) and crushed ores are thoroughly mixed together, roasted in a reverberatory furnace, and reduced to an impalpable powder in a suitable
mill. The heat and salt acting upon the sulphide of
silver produce the chloride of silver.-3d. Wrought iron




138        QU ARTZ OPERATOIR'S HAND-BOOK.
in small pieces with a pasty mixture of the chloridized
ores and water, are put into barrels having horizontal
axes, familiarly known as German barrels. These, each
making twenty revolutions a minute, are run two hours.
The effect of the iron is to revive the silver to the metallic state. —4th. Quicksilver is then poured into the barrels, after which they are run sixteen hours continuously,
except the time taken to regulate the consistency of the
pulp by the addition of ore or water. At the end of the
time run, the casks are filled with water and revolved
quite slowly for one or two hours, when the mass is discharged into large vats, and the amalgam separated by
washing. -5th. The proportions to the ton of ore valued
at seventy-five dollars per ton, are: salt, added before
roasting, 200 pounds; wrought iron to the ton of roasted
ore, 200 pounds; quicksilver to the ton of roasted ores
1,000 pounds.
Ayer's Process.-The ore as it comes in blocks from
the mines is heated in a furnace and thrown into brine
or alkali water, by which operation it is broken into
small fragments. It is then subjected to a further reduction and to the process of amalgamation.
Kent's Process. —"Kent's Patent Improved Freiberg
Process, for treating gold and silver ores, consists in the
preparation of crushed or pulverized ores, and tailings,
by caking them with a solution of the chloride of sodium,
or salt and water, introduced in any manner so as to
admit of forming the crushed ore into cakes, lumps or
bricks."  Only three per cent. of salt is used.  The




sEim.                    139
bricks are calcined in a kiln, and it is estimated that three
cords of wood and twelve hours' time will calcine 10,000
bricks, or 30 tons of ore. The amalgamation is effected
in barrels-differing in some of their features fiom those
of usual construction.
Veach Process.-The only essential difference between
this and the Freiberg process consists in the employment of tubs instead of barrels, and the use of steam
directly in the pulp.  Vertical plates of iron or copper,
for reviving the silver from the- condition of a chloride,
are fastened to the "muller arms," so as to revolve
edgewise through the pulp or mass. The operations are
greatly hastened by the application of steam, so that not
more than five or six hours are required for the treatment of a charge of ore.
EXTRACTION OF SILVER FROM COARSE
COPPER.
1st. Coarse copper containing silver, as it comes from
the furnace, is raised first to a bright red heat, then pulverized and roasted with salt, by which operation the
silver present is converted into the chloride of silver.2d. The roasted mass is then treated in barrels with
quicksilver, which decomposes the chloride and amalgamates with the revived silver in connection with a little
copper and iron.-3d. The amalgam  is reto-rted and
cupelled.




140        QUARTZ OPERATOR 8 [IAND-BOOK.
EXTRACTION OF SILVER FROMI COPPER
MIATTrE.
Ist. The copper matte, composed of the sulphides of
silver, copper, iron and other base metals as it comes
from the furnace, is pulverized and"roasted with salt and
lime. The former, by the action of its chlorine, converts
the various metals into chlorides, which, with the exception of the chloride of silver, the latter decomposes.-2d.
The roasted matte is then treated in barrels with quicksilver which decomposes the chloride of silver and amalgamates with the metal.-3d. The amalgam is then
pressed, retorted and refined.
In Copper Kettles.-lst. This process, known as the
"Hot Process," is chiefly employed in South America,
and there only on the better class of ores-especially
those rich in native silver, or in the chloride, iodide or
bromide of silver. These being finely pulverized and
concentrated by washing are introduced with considerable water into coppier-bottomed kettles and boiled.2d. Salt amounting by weight to ten or fifteen per cent.
of that of the entire mass is dissolved in the boiling pulp
while it is being stirred.-3d. Mercury of less weight
than that of the silver present is added to the charge,
and the stirring continued. More quicksilver is introduced whenever a test indicates the least dryness of amalgam.-4th. The amalgam and gangues are separated
by washing; the former is "squeezed," retorted and refined, the latter often treated by the Patio process.




SILVER.                  141
Pan Process.-lst. The ores of silver as they come
from the mines are prepared for the pan usually by
being crushed wet to a granular state by stamps and run
into a series of large settling tanks. However, to crush
wet and very Jfine at the same time is objectional, as
much silver thereby'is carned off in the water. The
ores are commonly reduced so as to pass through No. 4
or No. 5 Screens. They are sometimes crushed diry, and
sometimes roasted before going to the pani. Those especially containing much antimony should be roasted.2d. Charges of the reduced ores-raw for example-with
sufficient water to form a soft, pasty mass, are put into
the pans and ground to the slime condition. This ordinarily requires, in the Excelsior Grinder and Amalgamator about three hours.  Water is added occasionally
during the grinding process to preserve the proper consistence of the pulp, which, if too thick, causes a waste
of power, and if too thin does not intimately mix with
the quicksilvei.-3d. Quicksilver is put into the machine
and thoroughly incorporated with the mass; which condition is indicated by small globules of mercury appearing
on the surface of the pulp while it is in motion, and by
their slowly disappearing on its coming to rest. Millmen differ as to the proper time for its introduction;
some maintaining that it should be simultaneous with
the charging of the machine with ore, others that it
should be later-that the grinding should first be accormplished, then the mullet raised, the motion decreased,
and the quicksilver mixed with the mass.-4th. Chem



142        QUARTZ OPERATOR'S HAND-BOOK.
icals, differing in kind and proportions, to an indefinite
extent have been employed. As to their practical value,
it is sufficient to observe that, in. treating the same
amount of ore, scarcely a pound is now used, while tons
formerly were. This observation applies to the treatment of raw ores containing the sulphide of silver. Prior
to drawing off the pulp, the pan may be nearly filled by
letting in water while the muller is running. This will
aid in depositing the amalgam and quicksilver, also in
drawing off the charge. The pan should be well washed
out before being recharged. When it is desired to
"clean up" the Excelsior Pan, the key in the mullerscrew must be removed, and.the muller run up out of the
way of the operator. As the sides of the stationary
plates slant outward, it requires but very little labor to
wash down the material covering them to the circumference of the machine, whence it may readily be drawn
off.-5th. Heat nearly to the degree of boiling water is
universally approved of by the amalgamators of silver
in paus. —6th. The proportions usually observed in operating the " Excelsior Grinder and Amalgamator " with
muller four feet diameter, are: ore to the charge, 1,500
pounds; number charges worked in 24 hours, 7; revolutions of muller per minute, 60 to 65; quicksilver to
charge ore valued at fifty dollars a ton, 200 pounds; heat
(produced by steam), 200~ Fahr. —7th. The charge is next
drawn off into the separator, where it is slowly and carefully washed in abundance of clean water. For the first
fifteen or twenty minutes after the separator has been




sLMVEx                   143
charged with the slime-pulp, but little more water than
was drawn from the Grinder and Amalgamator or Pan
should be employed in it, at the expiration of which
time the machine may be nearly filled with water and
kept running for a half hour or more; then the stoppers
should be drawn from the side, one after the other, commencing at the uppermost, and the pulp run off slowly.
In the meantime a clean stream of water should be let
continuously into the machine. The Conoidal Separator
being employed, the amalgam is deposited with the quicksilver in the bowl and spiral groove at the circumference.
The most of the quicksilver is drawn off through an aperture in the bottom of the bowl.  The amalgam is
washed, squeezed and retorted.-Plumbiferous silver amalgam squeezed at a temperature of 144~-180~ Fahr., the
lead goes with the mercury; squeezed at a lower temperature, the lead remains in the bag. The pulp is run
off from the separator into agitators and various contrivances employed to gather the stray particles of mercury,
amalgam, and in some cases to concentrate the richer and
heavier portions of the tailings.
REcIPEs. —The following recipes taken from Guido
Hlistel's "Processes of Silver and Gold iExtraction,"
are a few of the many employed in Nevada, to the ton
of ore:
a Chloride of copper................ 13 pounds
Common salt....................  60   "
b Chloride of iron...........     13   "




144        QUARTZ OPERATOR!S HAND-BOOK.
C Sulphate of iron.................   1 pound
Sulphate of copper...........   8 pounds
Common salt..................... 80   "
d Sulphuric acid.................     3 
Sulphate of copper..............   2 "
Salt.............                  15
e Sulphuric acid....................  2   "
Alum.................,......    2
Sulphate of copper..............         "
f Sulphate of copper............... 18 ounces
Sulphate of iron................. 16'
Sal ammoniac....................    8   "
Common salt.............            2 pounds
g   lu............................        ~" 
Sulphate of copper.......... 1 "
Salt............................ 40   "
4h Muriatic acid........             30 ounces
Peroxide of manganese......          8   c
Blue vitriol.                       10 "- 
Green vitriol..................    10   "
i Common salt..................... 15 pounds
Nitric acid................ 1 to 2   "
Sulphate of iron..              1 to 2
Ak Common salt..                     25 "
Blue vitriol....................  2
Catechu........................   2   "
Niote.-a, b,,c, are calculated for ore containing from
two hundred and fifty to five hundred ounces of silver in
sulphurets. All chemicals, except salt, are used in solu



:sLVER.                  145
tion. The salt is charged half an hour before the chemicals are put in
MSODIUM AMALGAMX
Sodium and mercury at a slightly elevated temperature combine energetically with each other, forming sodiumn amalgam, which has a strong affinity for gold and
silver, and several other substances. The application of
this principle: of attraction to the practical amalgamation
of gold and a silver was first made by Prof. Henry Wertz
of Neaw York. Experience goes-far to show that sodium
amalgam, for the extraction of gold and 4silver from their
gangues, in a variety of cases may by skillful hands be
employed to advantage. A very free use, however, will
often be found injurious on account of its affinity for
many other -substances than gold and silver. Its  use is
recommended in the treatment of gold-bearing quartz in
batteries, pans, barrels or;arastras, in extracting gold or
silver from sweepings, and in:amalgamating silver ores
in which the silver has.been reduced to the metallic
state:.:also in cases of "fi'ouring" and -" sickening" of
the:quicksilver, and,in "cleaning up,".espcially when
a portion of the mercury and amalgam is in a finely
divided:state, or scum form. The ratio observed is: one
part of sodium to two thousand -r:twenty-five hundred
parts of quicksilver by weight.
7y




146       QUARTZ OPERATOR'S HAND-BOOK.
PURIFICATION  OF MERCURY.
Mercury, for the purposes of amalgamation, should be
pure; most foreign substances, as lead, zinc, or bismuth,
diminish its properties of combining with gold and silver.
To free from these and other impurities:
1st. Distil the impure mercury. A retort for this process may readily be made of a common quicksilver flask
and iron pipe of syphen form. The short leg of the pipe,
a few inches long, is attached to the flask in the place of
the removed stopper. The long leg, three or four feet in
length, inclines downward from the bend. The retort
should not be over two-thirds filled with mercury. The
heat ought first to be applied to the short leg of the pipe
and upper part of the retort, then to all parts of the flask
alike. The long leg of the pipe must be kept cold. This
may be effected by wrapping it with cloths and pouring
on cold water. The discharge end may also be immersed
in cold water, kept in the receiver. The heat should be
uniform, and the distillation slow. The common covered
retort is preferable to the one described.
2d. Heat, and frequently agitate the distilled mercury
in thin sheets with one part nitric acid and two parts of
pure water. The heat should be kept at 1200 Fahr. for
several hours. Repeat these operations until satisfactory results are obtained; then pour off the mercury for
use.
3d. Digest the crystallized nitrate of mercury in nitric




SILVER.                 147
acid; then dilute the solution, filter, precipitate the mercury by metallic copper, and add it to the mercury
already obtained; or the nitrate of mercury may be converted to a liquid simply by heat, and the metal then
precipitated by copper plate.
QUICKSILVERING OF COPPER-PLATE.
First, thoroughly cleanse the surface of the plate, and
rub it over with quicksilver or with the nitrate of mercury. The surface is sometimes cleansed by simply
scouring it with wood-ashes, brick-dust, or fine sand;
and sometimes by washing it with dilute acid or strong
alkali. When acid is employed, its corrosive properties
should be neutralized before the application of the quicksilver. Nitrate of mercury, when crystallized, is readily
converted to a liquid by heat, in which state it may be
applied as a wash to the plate. Sodium amalgam may
also be used to good effect in coating copper plate with
quicksilver; in which case not as much care need be had
in cleansing the surface of the plate as by the other methods, before its application.
CUPELLATION  OF GOLD AND SILVER.
1st. The cupellation of gold and silver depends upon
their permanence and the oxidability of lead with which
in a state of fusion they readily enter into combination.




148       QUARTZ OPERRATOR`S' HAND-BOOK.
The mode of cupelling gold andl silver in their sever-al
relations is the same.
2d. The alloy, consisting of lead and gold or silver, or
lead, gold and silver, is melted in: a circular reverberatory
furnace, provided with openings through its- sides for
the admission of metal, heat, currents of air, and for the
escape of vapors or litharge. The escape is opposite the
blast opening. The roof, or top of the furnace, is of dome
form, and movable. At each cupellation, the hearth,
usually of concave form, is broken up and replaced by
one made of clay, sand, and carbonate of lime.
3d. Blasts, or currents of air, are blown continually
during the operation upon the surface of the fused alloy,
promoting oxidation of the lead and causing the litharge
or oxide of lead to pass out through the escape opening.
The gate-way of this opening is kept level with the surface of the metal within. The metal thus separated from
the lead remains on the hearth of the furnace, either as
an alloy of gold and silver, or as one of them in nearly $
pure state. It is deprived of what lead it may contain
by the humid way of assay. If the metal obtained be an
alloy of gold and silver, it is subjected to the process of
inquartation, to which reference is here made.
REFINING  OF GOLD AND  SILVER.
The refining of gold and silver is: the process by which
these metals individually are brought to a state of purity.




SILVER.                   149
It properly embraces Quartation, Granulation, Parting,
and Reduction.
1st. Quartation is the alloying of one part of gold with
three parts of silver, preparatory for humid operations.
2d. Granulation is effected by pouring the prepared
melted alloy through a fine iron sieve into water, or
directly upon a bundle of twigs immersed in water.
3d. Parting takes place by subjecting in a proper
vessel, as glass, the granulated alloy to the action of
boiling nitric acid, by which the silver with the base
metals, if any are present, is dissolved out of the alloy,
leaving the gold pure, and in the form of the original
granules. In this operation 100 parts of silver require
149 parts of nitric acid of specific gravity 1,32 for oxidation and solution.  Boiling concentrated sulphuric acid
is sometimes employed instead of nitric acid.
4th. Reduction.-The granular gold is taken from the
dissolving vessel, digested in boiling nitric acid, washed,
dried, melted with a little nitre and cast into ingots.
The silver of the nitric solution is precipitated by the
introduction of copper plates. The precipitate is washed
in water, pressed, melted with nitre, and borax, and cast
into ingots. The silver in solution is sometimes converted into the chloride of silver by a solution of salt
(chloride of sodium), and then reduced with carbonate of
soda or other proper flux.




AP.PLIED ME~CHANICS.
THIN CYLINDERS.
To determine the thickness of thin hollow cylindersthe internal radius, pressure. and tenacity of the material
being given:
R1ule.-Multiply the: internal radius in inches by the
fluid pressure in pounds per square inch, and divide the
product by the tenacity per square inch of the material.
fx. —-The internal radius of a cylinder being thirty
inches, the fluid pressure two hundred and fifty pounds
to the square inch, and the tenacity of the material of
the cylinder twelve thousand pounds per square inch,
what is the thickness of the cylinder?
Cal. 250 x 30 —7500; 7500  12000=  inch thick.
Ans.
To determine the fluid pressure-the internal radius,
thickness of cylinder, and tenacity of material being
given:
BRue. —Divide the product of the thickness of the cylinder and tenacity of the- material per square inch by the
internal radius.
Ix.- The thickness of the cylinder being one-fourth of
an inch, the tenacity eighteen thousand pounds, and the
radius six inches, what fluid pressure will the cylinder
stand per square inch?
Cal. 18000x+' 6=750 pounds. Ans.




APPLIED MECHANICS.             151
THICK HOLLOW CYLINDERS.
To determine the thickness of thick hollow cylinders
-the internal radius, the fluid pressure, and the tenacity
of the material of the cylinder being given:
Rule.-Subtract one (1) from the square root of the
quotient of the sum and difference of the tenacity per'
square inch of the material of the cylinder and the filuidpressure per square inch, and multiply this difference by
the internal radius.
EX.-The internal radius of a thick- hollow cylinder
being nine inches, the tenacity of the material of the cylinder ten thousand pounds, and the fluid pressure eight
thousand pounds per square inch; what is the requisite
thickness of the cylinder?
Cal. —Sum  of tenacity and fluid pressure, 10000 +
8000 = 18000; difference of tenacity and fluid pressure,
10000-8000= 2000; quotient of sum  and difference,
18000 2000=-9000; square root of quotient, $/9-3;
difference between root and one (1), 3-1 = 2; product
of radius and difference, 9 x 2 18 ins. Ans.
To determine the fluid pressure per square inch which
a thick hollow cylinder will withstand-the internal and
external radii and the tenacity of the material of the
cylinder being given:
RRule. —Divide the difference of the squares of the radii,
and multiply the quotient by the tenacity per square
inch of the material of the cylinder.




152       QUARTZ OPERATOR'S HAND-BOOK.
-Ex.-The internal and external radii of a thick hollow
cylinder being respectively nine inches and twenty-seven
inches, and the tenacity per square inch of the material
of the cylinder ten thousand pounds, what fluid pressure
per square inch will it withstand?
Cal.-Square of external radius, 27 x 27='729; square
of internal radius, 9 x 9=81; difference of squares, 72981=648; sum of squares, 129+81=810; and 10000x
648' 810= 8000 pounds. Ans.
RELATIVE GRINDING CAPACITY OF DIFFERENTLY FORMED GRINDING PLATES.
Rule 1. —To determine the relative grinding capacity
of tractory-ormed plates or mullers: Multiply the difference,of the squares of the greater radius of the muller,
and the radius of the opening in the same, by twice the
greater radius.
Ex.-A tractory-muller having its greater radius one
(1) and the radius of its opening one-third (i) what is its
relative grinding capacity?
Cal. 1 —=-; -x 2=z-=1.778. Ans.
Rule 2.-To determine the relative grinding capacity
of flat-bottomed or plane mullers: Multiply the difference of the squares of the greater radius of the muller,
and the radius of the opening in the same, by the sum of
the greater radius and the radius of the opening.
x. —A plane-muller having its greater radius one




APPLIED MECHANICS.              153
and the radius of its: opening. one-third, what is its relative, grinding capacity?
Cal.  1 —-1;-1+; x:-:1.1852  Ans.
Rule 3.-To determine the relative grinding capacity'
of conical' plates- or mullers- -when the height of the cone
is equal to one-half the greater radius: Find-: the grinding effect, as in Rule IL and multiply the: result by  1.118.
1,1852 x 1.118=-i3251. Ans.
FRICTION.:st. For a cylindrical journal, the: leverage of the friction is simply the radius of the journal. —2d. For a flat
pivot, the: leverage is one-half the radius of the pivot.- 3d.
For a conical pivot the leverage is equal to the quotient
arising by dividing one-half the radius of the base of the
cone by the sine' of the angle included between the: axis
and side of the cone.-4th. For Schide's''anti-friction"'
pivot the leverage is the entire, radius of the pivot.-5th.
For a collar, the leverage of friction is equal to one-half
the sum of its externals and internal radii,
WATER PIPES.
To determine the velocity of water per second, flowing
through long pipes —the head or height of' reservoir
above the point of delivery, the length and diameter of
the pipe being given:
_Rule. —Multiply the- product: of the head and diameter




154       QUARTZ OPERATOR'S HAND-BOOK.
of the pipe in feet by twenty-three hundred: divide this
product by the sum of once the length and fifty-two
times the diameter of the pipe, and extract the square
root of the quotient.
E. —The head is six hundred feet, the diameter of the
pipe nine inches, the length of pipe six thousand feetWhat is the velocity of the water per minute?
Cal. —Diameter of pipe-9 inches=.75 feet; product
of head, diameter, etc., 600 x 2300 x.75=1035000; sum
of length and product, 6000 + (52 x.75) =6039; quotient,
1035000  6039-=171.386; square root, 4171.386=13.09
feet velocity per second; velocity per minute, 13.09 x
60=785.4 feet. Ans.
To determine the head, the velocity, length and diameter of pipe being given —(by Tables V. and VI.):
Rule. —Multiply the length of the pipe in feet by the
constant (C) opposite the given velocity in Table, and
divide the product by twelve hundred (1,200) times the
sum of the diameter of the pipe in inches and the constant (C) opposite the given diameter of pipe in T:able.
Ex.-It is required to determine what head of water
is necessary to force water through 1,500 feet of six-inch
pipe at a velocity of 180 feet a minute.
Cal.-By Table V., constant opposite velocity 180=
62.13; by Table VI., constant opposite diameter 6 =.078;
then 62.13 x 1500  1200 (6.078)=12.77 feet. Ans.
To determine the velocity-the head, length and diameter of pipe being given —(by Tables V. and VI.):
Rule.-Multiply twelve hundred (1,200) times the head




APPLIED MECHANICS.             155
by the sum of the diameter of the pipe and its constant
found in Table VI., and divide the product by the length
of the pipe. The quotient will be the constant; opposite which find the velocity, in Table V.
Ex.-The head being 12.77 feet, the diameter 6 inches,
and length of pipe 1,500 feet, what is the velocity?
Cal. 1200 x 12.77 x 6.078' 1500=62.13 constant, opposite constant 62.13 find velocity 180 feet. Ans.
The relative quantities of water, which will in the
same time flow equal distances through straight, curved
and right-angled pipes, are respectively 140, 100 and 90.
VELOCITY OF STREAMS.
In a stream the velocity is greatest at the surface and
in the middle of the current. To find the velocity of a
river or brook:
Bule.-Take the number of inches that a floating body
passes over in one second in the middle of the current,
and extract its square root; double this root, subtract it
fiom the velocity at top and add one (1); the result will
be the velocity of the stream at the bottom; and the
mean velocity of the stream is equal the velocity at
the surface, less the square root of the velocity at the
surface increased by five-tenths of one (.5).
Ex. —If the velocity at the surface and in the middle
of a stream be thirty-six inches a second, what is its
velocity at the bottom, and what its mean velocity.




:156       q       o~.QUARTZ OPIERpR    S HAND-BOOK.
CT.   a36x 2=.212; then  =6+.. —l12.25 -iache   per
second velocityat bottom Ans.  ns.  Then36+5-6 =30.5
inches per second mean velocity. Ans.'WATER POWER.
The theoretical velocity with which a liquid issues
from an orifice in the bottom or side of a vessel that is
kept full, is equal to that which a heavy body would
acquire by falling from the level of the surface to the
level of the orifice; this is nearly eight times the square
root of the head or distance fallen in feet. The practical
velocity estimated for the entire opening is considerably
less than the theoretical velocity, owing to oblique currents and to friction. The oblique currents:produce a
contraction in the vein or stream. The minimum transverse section of the contracted vein is the plane at which
the velocity is nearly equal to the theoretical velocity.
The quantity of water which will be discharged in a certain time depends upon the form of the opening as well
as upon the head. Thus by means of a conical tube of
the form of the contracted vein, the velocity at the opening or smaller end of the tube is nearly equal to the theoretical velocity. The actual velocity estimated for the
entire opening when constructed as ordinarily and not
large, is five and four-tenths the square root of the head
in feet.
To determine the velocity with which water will filo




APPLIED) MECHANIC,.            157
under different heads, and under different conditions, see
Tables.
Ex. 1.-Let it be required to determine the velocity
with which water will flow under a head of six inches
through an aperture of ordinary construction.
Cal.-B-y Table IV. in the column called "Square root
of head," and opposite the "Head six inches" we find,.70711. Multiply this number by 8, thus:.70711 x 8=5.66
feet per second; this is the theoretical velocity. Multiply the same number by 5.4;.70711 x 5.4=3.82 feet per
second; this is the experimental velocity.
Fx. 2.-Let it be required to determine the number of
pounds of water which will flow in one minute under a
six-inch head through an aperture two inches by one
hundred and fifty inches.
Cal.-The velocity per second, as found above is 3.82
feet.'The velocity per minute then will be 3.82 x 60229.10; the area of the opening is 150 x 2=300 square
inches. This expressed in square feet, is 300  144= —2.08.
Multiplying the length of the stream of water, or in other
words the distance which the water flows in one minute,
by the area of the opening, and we obtain the cubic feet
of the quantity of water which will flow out in one
minute, thus: 229.10 x 2.08=477.3 cubic feet. By Table
XIII. we find that a cubic foot of water weighs 62.38
pounds; hence 477.3 x 62.38=29773.54 pounds.
Were it now required to find the power which this
water would exert on a water-wheel, we should simply
have to multiply the number of pounds of water thus




158        QUARTZ OPERATOR'S HAND-BOOK.
found by the fall in feet; this would give us the theoretical power in the water. To determine the practical
power, we should have to multiply the theoretical power
by the efficiency of the water-wheel; and if we desired
to express the power in units of horse-power, we should
have to divide the pound power thus found by 33,000.
As a practical illustration, take the common centre discharge-wheel, and let the fall be forty feet. The efficiency
of this wheel under the most favorable circumstances
does not exceed.60. Taking the highest efficiency, and
we have (see Table I.) 29773.54 x 40 x.60  33000=21.65
horse-power.
To determine how much more water will flow under
one head than under another:
Rule.-Divide the square root of the greater head in
feet by the square root of the less.
Ex. -How much more water will flow under a threefoot head than under a six-inch head?
Cal.-By Table IV. we find the square root of the threefoot head to be 1.73205, and the square root of the sixinch head to be.70711. Then 1.73205-+-.70711=2.45
times as much. Ans.
WATER-WHEELS.
Water, as a power or force, is exerted on water-wheels
by its weight and by its impulse. Weight and impulse
are combined on the overshot and breast-wheels. The
theoretical work accomplished by weight is the product




APPLIED MECHANICS.              159
of its force and the vertical distance through which it is
exerted. The theoretical work accomplished by impulse
is the product of the force produced by the weight of the
flow of water and the vertical height or head necessary to
produce the velocity with which the weight moves.
The available work depends not only upon the magnitude of the force exerted, but upon the direction of
that force in reference to the direction given to the
resistance; also upon the form of the floats or buckets
of the wheel, friction, losses by leakage, etc.
The velocity, per second, of the overshot wheel at its
circumference should be about six feet; which is due a
head of two feet three inches. The vertical distance from
the centre of the opening in the gate to the surface of
the water in the flume or reservoir is termed the " head,"
and the vertical distance from the centre of the opening
in the gate to the lower edge of the wheel, the " fall."
To find the horse-power of various water-wheels:
-Rule.-Multiply the product of the coefficient (see
Table VII.) opposite the given head, the area of the opening in the gate in square inches, the entire head in feet
(in case of the overshot or breast, the head by 40, and
the fall by 78) by the efficiency of the class of wheel,
pointing off six figures as decimals.
DE. 1.-The dimensions of a stream are two inches by
two hundred inches, the head two feet three inches, and
the fall ten feet; what is its horse-power applied to a
breast wheel?
Cal. 2 x 200=400 square inches gate opening; coef



160        QUARTZ OPERATOR'S HAND-BOOK.
ficient, by Table VII. opposite 2 feet 3 inches=64; efficiency, by Table IL arising from impulse=40; efficiency
by Table II. arising from weight= 78; head 2 feet 3 inches
=2.25; product of efficiency and head, 2.25 x 40=-90;
product of efficiency and fall, 10 x 78=780; sum of products, 780+90=870; then 870 x400 x 64=22.27 horsepower.  Ans.
Ex. 2-The dimensions of the stream are ten inches
square, the head twenty-five feet; what is its horsepower applied to a good turbine?
Cal.-Square inches in opening, 10 x 10=100; coefficient by Table VII. for 25 feet= 213; efficiency by Table
II. of turbine, 68; then 100 x 213 x 68 x 25 —36.21 horsepower. Ans.
STEAM POWER.
Steam, as a force, acts by elastic pressure. The law
that, in compressing a perfect gas the volumes occupied by a given quantity are usually proportioned to
the pressures, does not hold good in relation to saturated
steam.
By Table VIII. it will be seen that the volume of steam
under a pressure of thirty pounds to the square inch produced from a cubic inch of ice-cold water is eight hundred and thirty-eight cubic-inches, while under a pressure of ninety pounds to the square inch the volume is
twohundred and ninety-eight cubic inches. Thus the
ratio of the two pressures is as 30 to 90 or as 1 to 3,




APPLIED MECHANICS.             161
while the inverse ratio of the respective volumes of steam
is as 1 to 2.81. The mechanical effect deduced from the
above data is as follows: 838 x 30' 12=2095, and 298 x
90  12=2235; 2235-2095-140, difference of mechanical effects, and 140'2095-.0668; showing an advantage, all other things being equal, of nearly seven per
cent. in favor of using steam at the higher pressure.
By Table IX. for estimating the mean pressure of
steam for a given cut-off of stroke, the coefficient for onefourth cut-off is 5 72 in the unjacketed cylinder, and 582 in
the jacketed cylinder. The calculation on this data shows
an advantage of one and three-fourths of one per cent.
in favor of the jacketed cylinder for the given cut-off of
stroke.
The back pressure of steam in the cylinder of an engine of ordinary structure is found by experience to be
about four pounds to the square inch above the atmospheric pressure; the velocity of piston being three hundred feet per minute. But in the best engines of modern
construction, the back pressure is frequently below one
pound, with even higher speeds of piston. It is also found
that the excess of the back pressure above the atmospheric pressure varies nearly as the velocity of the piston.
To find the mean pressure of steam for a given cut-off
of stroke:
-Rule.-Multiply the excess of the pressure of steam
above the atmospheric pressure, per square inch, as it
enters the cylinder, by the tabular coefficient opposite
the given cut-off, pointing off three figures as decimals,




162        QUARTZ OPERATOR'S HAND-BOOK.
and deduct from the product the tabular correction for
the same cut-off.
Er.-With steam entering the cylinder at a pressure
of ninety pounds to the square inch, and cut off at threetenths (1-3) stroke, what is the mean pressure?
Ccal.-For unjacketed cylinder. By Table IX. the coefficient for -3 stroke=.63 9. Correction for same= 5.307.
Then.639 x 90=57.510; 57.510-5.307=52.203 pounds.
Ans.
C7al.-For jacketed cylinder. By Table IX. the coefficient for 3 stroke is —.648. Correction for same_-5.174.
Then, 648 x 90 —58.320; 58.320- 5.174-53.146 pounds.
Ans.
The "indicated " power of a steam-engine is equal to
the product of the area of the piston in inches, the
pounds pressure of the steam per square inch, and the
distance travelled by the piston in one minute. The
effective power in excess of back pressure, loss and condensation in well-constructed engines is usually about
eighty-four (.84) one hundredth of the indicated or theoretical power. The nominal power bears no fixed relation
to the indicated, nor to the effective power. In calculating the nominal power, the mean effective pressure in
low pressure engines is assumed to be seven (7) pounds,
and in high pressure engines twenty-one (21) pounds.
The nominal velocity of the piston, whether in high or low
pressure engines, is 128 times the cube root of the stroke
in feet. The range is from 120 to 300 feet per minute.
In practice the piston not unfrequently is made to travel




APPLIED MECHANICS.             163
900 feet and upwards a minute. Experience has determined no limit beyond which it cannot be run with
advantage.
The total heat of combustion estimated in pounds of
water raised 1~ Fahr. is 14,500 times the weight of fuel
-pure carbon. This is equivalent to 11,194,000 foot
pounds of work per pound of fuel. It is also equivalent
to 966 times the weight of water which the same fuel
will evaporate from 2120 Fahr. In practice, not usually
over six per cent. of this immense expenditure of heat is
economized. From five to seven pounds of coal, or from
20 to 30 pounds of pine wood, ordinarily are allowed to
the horse-power per hour. But in the best examples of
modern practice a horse-power per hour, with an expenditure of from three to four pounds of good coal, is not
unfrequent. The Babcock & Wilcox engine in the Druid
Mill, near Baltimore, develops power for 2.24 pounds
of chestnut coal per horse-power perhouir, which is probably the best result yet attained in stationary engines.
It may further be remarked that in practice, "for each
nominal horse-power, a boiler requires one cubic foot of
water per hour, one square foot of fire-grate surface, one
square yard of heating surface, one cube yard capacity,
twenty-eight inches flue area." Or for each:nominal
horse-power a tubular boiler, working to about double its
nominal horse-power, requires one cubic foot of water
per hour, ten square feet of heating surface (the whole
tube surface being taken as effective), one-half square
foot of fire-grate, ten square inches sectional area of,




164        QUARTZ OPERATOR'S HAND-BOOK.
tubes, thirteen square inches flue area, six square inches
chimney area, eight cube feet total boiler capacity and
two cube feet of steam room.
The diameter of two cylinders being the same, for
instance, six inches each, and the length of stroke of one
ten inches, and of the other fourteen inches, the power
of each, theoretically, will be the same, the velocity of
piston being the same. In pi'actice, there is a slight, and
but a slight, percentage in favor of the longer cylinder.
In two cylinders, one being ten inches and the other
twelve inches in diameter, and each twenty-four inches
long, and their pistons run under the same pressures per
square inch, and at the same velocities, their inside relative friction would be as 25 to 30, and aside from this
small difference, their relative powers would be as 25 to
36. Again, in two cylinders, one sixteen inches and the
other twenty inches diameter, each forty-eight inches
long, run under similar circumstances, the inside relative
friction will be as 100 to 125, while their respective
powers will be as 100 to 1561. This small difference in
friction, as compared to the whole, is not generally taken
into account.
To find the effective horse-power of a non-condensing
steam-engine:
_Rule.-Multiply four times the square of the diameter
of the piston in inches by the product of the number of
revolutions, length of stroke in feet, and the average" forward pressure of steam in pounds per square inch above
atmosphere, pointing off five figures as decimals.




APPLIED MECHANICS.             165
Ex.-What is the effective horse-power of an engine,
the diameter of the piston being sixteen inches, the
length of stroke three feet, the number of revolutions fifty
per minute, and the average forward pressure, above the
atmospheric pressure, seventy-one pounds per square inch.
Cal.  16x16x4x50x3x71=109.05.
_e. 2.-What is the effective horse-power of an engine,
the diameter of the piston being twelve inches, the length
of stroke two feet, the pressure of steam as it enters the
cylinder sixty pounds in excess of atmospheric pressure,
cut-off at one-half stroke, and making seventy-five revolutions per minute?
By Table IX. coefficient for ~ stroke=.833; correction for same-2.455;.833 x 60=49.980, 49.980=2.455 —
47.525 average pressure. Then 12 x 12 x 4 x 47.525 x 2 x
75 = —38.59 horse-power. Ans.
NITRO-GLYCERINE.
Nitro- Glycerine has for its formula C6 N3 H5 06, which
by composition is carbon 17.06, nitrogen 19.91, hydrogen 2.36, oxygen 60.66.
Preparation.-Syrup of Glycerine is slowly dropped
into a mixture composed of equal volumes of nitric and
sulphuric acids contained in a strong vessel surrounded
by ice. The mixture is thoroughly agitated after each
addition of the syrup. The nitro-glycerine of an oily
form is removed from the surface and repeatedly washed
with clean water. It is sometimes dissolved in alcohol or




166        QUARTZ OPERATOR'S HAND-BOOK.
ether, and precipitated with water. The only precaution
necessary in its preparation is to keep it cold.
Properties.-It is a pale yellow liquid, heavier than
water, inodorous when pure; has a sweet, pungent and
aromatic taste. It is poisonous, producing headache
when placed even in small quantities upon the tongue,
or when its vapors are inhaled. Its explosive power is
about ten times that of ordinary blasting powder. It
explodes when pure and at a moderate temperature by
concussion alone. It is soluble in pyroligneous acid, and
when in solution is not explosive. Water precipitates it
from its solution.
Advantages.-lst. It requires a smaller hole than gunpowder.-2d. It obviates tamping, as water is employed
to fill the holes.-3d. If used extensively it would be
cheaper than gunpowder.-4th. It may readily be exploded in water.-5th. It can easily be manufactured at
the mine or place where it is to be used.
Disadvantages.-lst. It (when pure) explodes by concussion alone. —2d. It (when impure) is liable to explode
spontaneously.-3d. It explodes at a temperature of.300~
Fahr.-4th. It is poisonous, as also are its vapors, thus
rendering its use impracticable in narrow subterranean
workings, especially if they are not well ventilated.
However, when it is better understood these disadvantages may be removed.




TABLES.
TABLE I.
Showing the best velocities of various water-wheels as
compared with the supply velocity:
Undershot and low breast, at circumference.50
Turbines, at the middle of ring of buckets...65
Reaction, at circumference...........97
Central discharge (common).............. 60
Overshot, at circumference................ 50
TABLE II.
Showing the average efficiency of various water-wheels
running under favorable circumstances as found by experience:
Undershot, having flat radial floats.........35
Poncelet, improved undershot.............60
Turbine (for example Jonval).............68
Reaction (for example the Scotch Turbine)..66
Central discharge (common).............. 55
Overshot and Breast (that part of fall acting by weight)...........'78
Overshot and Breast (that part of fall acting by impulse)..................40




168         QUARTZ OPERATOR'S HAND-BOOK.
TABLE III.
Showing the relative velocities with which water, under a constant head, will flow through differently formed
apertures:
Theoretical velocity................ = 8.
Velocity through a thin plate.....  -— 5.
Velocity through a tube two or three diameters in length projected outward=6.5
Velocity through a tube of the same
length projected inward............ 5.45
Velocity through a conical tube of the
form of the contracted vein.         =77.9
TABLE IV.
For estimating the velocity with which water will flow
under a given head, or a body fall from a given,height:
Sq. Root of        Sq.Root of    Sq. Rootof    Sq. Root of
f Head.              Head.        Head.         Head.
ft. in.        ft. in. ift.                ft.
I.28867 2  4 1.52752   5 2.23607  32   5.65685
2.40825  2  5 1.53456   6 2.44949 33   5.74456
3.50000 2  6 1.58II4   7 2.64575  34  5.83095
4.57735  2  7 I.60727   8 2.82843 35   5.9I608
5   -64549 2  8 I.63299   9 3.00000 36   6.oocoo
6.707II 2  9  I.65831 10 3.i6228 37   6.08276
7.76376 2 Io0.68325  I I 3.3662 38   6. I644I
8.8I744 2 I I 1.70782  I2 3.464I0 39   6.24500
9 -.86602 3  0  -1.73205 I3 3.60556  4    6.32456
10.91287 3  I 1.75589  I4 3.74I66 45   6.70820.II.95743 3  2 1-77952  15 3.87298 50   7.07I07




TBLES.                      169
Tab  IF. con itoired.
Sq. Root of     Sq Root of     Sq. Root o  Sq. Root of
W     Hei~ad.  #     hIead.       Head. P       Head.
ft. in.        ft; in.'t.         ft.
I  o  1.ooooo 3  3  1.80278 i6  4.00000  55  7.41620
I  I 1.04084 3  4  1.82574 17 4.12311  60  7.74597
I  2 I.080I2 3  5  1.84842  I8 4.24264  70  8.36660
I  3  I.II803 3  6  1.87082 19 4.35890  80  8.94427
I  4  1I-I5469 3  7  -.89297 20 4.47214  90  9.48383
I  5 I.I9024 3  8 I.9I485 2I 4.58258 I10  I0.00000ooooo
I  6  1.22474 3  9  1.93649  22 4.69042 125 11.18034
I  7 1.25830 3 10 I.95789 23 4.79583 150 12.24745
I  8 1.29100I    3 II  1.97909  24 4.89898 175 13.22876
I  9  1.32288 4  0 2.00000 25 5.00ooooo000 200 14. I42 I4
I I0 I.35400 4  I 2.02072 26 5.09902 225 15.00000
I II 1-38444 4  2 2.04I24 27 5. I96I5 250 I5.8 I39
2  0 1.41421 4  3 2.06156 28 5.29150 300 17.3205I
2  I 1.44339 4  4 2.08I67 29 5.38376 400 20.00000
2  2 1.47I96 4  5 2.10159 30 5.47723 500 22.36068
2  3 1.50000 4  6 2.12132 31  5.56776 600 24.49490
TABLE V.
Showing the heads of water necessary to maintain different velocities of water in one hundred feet of pipe:
v.       C.       v.       c.        V.       C.
6o      8.62       g,90   17.95     140I' 38.90
70     I I.40     100    21.56    1I50    44.00
80     I4.58      120     29.70      i8o    62.13
V. represents the velocities in feet per minute.  C
represents the constant numbers for these velocities.
8




170         QUARTZ OPERATOR'S HAND-BOOK.
TABLE VL
Showing the constant numbers for different diameters:
D.     c.      D.      C.      D.     C.
4.028     6.078      8.-34
5.053     7.I04
D. represents the diameter of the pipe in inches.  C.
represents the constant numbers for the diameters.
TABLE  VII.
Coefficients for estimating the horse-power of waterwheels:
o:           J a)x.          Q  
ft.  In.    ft.  in.     ft.  in.     ft.  in.
I  12   I  7  54   3  2   76    9 0  128
2  17   I  8  55   3  4   78   IO o I35
3  21   I  9  56   3  6   80   12 0  148
4  25   I IO  58   3  8   82   I4 0  i6o
5  28   I II  59   3 Io   84   x6 o  17I
6  30   2  o0  60   4  o   85   20 o0  I I
7  33   2  I  62   4  3   88   25 0  213
8  35   2  2  63   4  6   90   3  o0  233
9  37   2  3  64   4  9   93   36 o  256
IO  39   2  4  65   5  0   95   49 0  298
II  41   2  5  66   5  4   98   64 0  34I
I  0  43   2  6  67   5  8  Ioi   8i O  384
I  I  44   2  7  69   6  o  104  Ioo o  426
I  2  46   2  8  7o   6  6 6  I09  121     469
I  3  48   2  9  71   7  o. II3  I44 0  511
I  4  49   2 Io  72   7  6  II7  I69 0  554
I  5  51   2 II  73   8  o  I2I  I96 0  597
I  6  52   3  0  74   8  6 I24  225 0  639




TABLES.                    171
TABLE VIII.
Showing the pressures, temperatures and volumes of
steam.
P.',  T.     V. Po.    T.    I.  P.    T.    V.
I.  I02.I0  20582   60 292.7~ 437   80 372.9  I55
5.  162.3   3813   65 298.0  405  I90 377.5  148
I0.  193.3   2358   70 302.9  378  200 381.7  141
14.7 212.0   1642   75 307.5  353  2I0 386.0  135
15.  213.1   i6io   8o 312.0  333  220 389.9  129
20..228.0   1229   90 320.2  298  230 393.8  123
25.  240.1  996 I100 327.9  270  240 397.5  II9
30.  250.4    838  II0 334.6  247 250 41OI.   114
35. 1259.3    726  120 34I.1I  227  260 404.5  IIO
40.  267.3    640  135 350.1  203  270 407.9  io6
45- 274.4    572  I50 358.3  184  280 411.2    02
50.  28I.o    518  165 366.0  169  300 47.5   96
REMARK.-In the above table, P. denotes the total
pressure in pounds per square inch; T. the corresponding temperature, Fahr.; and V. the volume of the steam
compared to the volume of the water that has produced
it.




172        QUARTZ OPERATOR'S HAND-BOOK.
TABLE IX.
For estimating the mean pressure of steam for - given
cut-off of stroke 
UNJACKETED CYLINDER.  JACKETED CYLINDER.
_         -  I 0            0.w..I77   12.098   2 0.86   1.966
0-.244   II.113   2%.254   I0.966
-.303   10.246.3I4  10o.o084
8.356    9-467    8.370    9.26I
— A.407    8.717.417    8.570
-.496    7.409        -.505    7-29,7. *572    6.290          582    6. I45
-.639    5.307  -3-.648    5. 74;%-.697    4.454   A'.707   4.307.748    3.704    2.756    3.587
29%-.797    2.984   2.800oo    2.940.833    2-455    ~.840    2.352
g —.869    I.926  i-.874   1.852.894    r.558    -.9o0    1.470
2u.923    1.132   2 O.929    1.044
T0.945    o.808 T.0%  -945    0.8o08..960    0.588  -.960    o.588
~.976    0.353            976    0.353
J 7   986    0.206.986.206
-    *0.997    0.044. -997    0.044




TABLES.                  173
TABLE X.
SCOUR OF WATER-COURSE BEDS.
i foot per second will scour fine clay.
c c;    cc        "     "  "  sand.
i"     C'   "  coarse sand.
1  "         fine gravel.
2 feet    "      "    "  round shingle one inch diam.
3  "      a      "    "'  antaugular stones, size of an egg.
5j  "     "      "';   "  conglomerate.
TABLE XI.
MIEASURES OF ROCK), EARTH, ETC.
25 cubic feet of sand-=1 ton.
18 cubic feet of earth= — 1 ton.
17 cubic feet of clay= 1 ton.
13 cubic feet of quartz, unbroken in lode= 1 ton.
18 cubic feet of gravel or earth, before digging=27 cubic
feet when dug.
20 cubic feet of quartz, broken (of ordinary fineness coming from the lode)=1 ton contract measurement.
TABLE XII.
HARDNESS OF MINERALS-MAP-SCALE.
1. Talc; common laminated, light-green variety.
2. Gypsum; a crystallized variety.
3. Calcareous spar; transparent variety.




174:    QUARTZ OPERATOR'S HAND-BOOK.
4. Fluor-spar; crystalline variety,
5. Apatite; transparent variety.
5, 5 Scapolite; crystalline variety.
6. Feldspar; white cleavable variety.
7. Quartz; transparent.
8. Topaz; transparent.
9. Sapphire; cleavable varieties.
10. Diamond.
Note.-Care must be taken to apply the file to edges
of equal obtuseness.
MISCELLANEOUS XIII.
5760 grains=l pound troy=1  pound apothecary
480 grains=l ounce troy=l1 ounce apothecary.
12 ounces=l pound troy=l1 pound apothecary.
7000 grains=1 pound avoirdupois.
437.5 grains=l1 ounce avoirdupois.
16 ounces avoirdupois=1 pound avoirdupois.
252.458 grains=1 cubic inch distilled water, English standard 62~ Fahr., barometer at 30 inches.
252.693 grains=l 1 cubic inch distilled water, U. S. standard 39.83~ Fahr., barometer at 30 inches.
27.7015 cubic inches distilled water=l pound avoirdupois.
1 cubic foot distilled water=62.37929 pounds avoirdupois.
REMARK.-In ordinary calculations a cubic foot of
fresh water is taken at 62.5 pounds avoirdupois.




TABLES.                  175
1 cubic foot of salt or sea water=64.3 pounds avoirdupois.
231 cubic inches=8.388822 pounds avoirdupois=1 gallon
U. S. standard.
277.274 cubic inches=10 pounds avoirdupois=1 gallon
imperial.
221.184 cubic inches=8 pounds of pure water at its mmximum density=l1 gallon N. Y. statute measure.
2150.42 cubic inches=77.627413 pounds avoirdupois=
1 bushel U. S. standard.
REMARK. —The dimensions of the bushel measure are
18.5 inches diameter inside, 19.5 inches outside, and 8
inches deep; and'when heaped the cone must not be less
than 6 inches high, equal to 2747.7 cubic inches for a
true cone.
2211.84 cubic inches=80 pounds of pure Water at its
maximum  density=1 bushel State of New York
standard.
I grain gold 1,000 fine    =    $.0430663 mint value.
1 grain silver   "      -.0026936
1 grain copper   ".0000595
1 ounce gold     "      =     20.671791      c
1 ounce silver    "     --     1.292929      "
1 ounce copper          =.028571     "
REMARK.-Gold and silver, pure, are said to be 1,000
fine, or 24 carats fine.
The standard fineness of the United States coin is 900,
or 24 x.900= 21.6 carats fine,




QUARTZ MINING MACHINERY.
The undersigned would respectfully state that he is
prepared to manufacture and furnish at the lowest prices
all kinds of Quartz Mining Machinery; to superintend
its erection; to furnish drawings, specifications, and
estimates for the same. Also to visit, survey, examine
and report on mines with a view to their character,
probable value, and the best methods for their development and the working of their ores.
P. M. RANDALL,
44 Courtland Street, New York.




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cloth..............................                          2.~4  
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Is illustrated and explained by numerous diagrams and representations of machinery.
This new edition has been revised and enlarged by Chief Engineer J. W. King, U. S. Navy,
brother to the deceased author of the worlk."-Boston  Daily Adtiser.
McCORMICK (R. C.).  Arizona: Its Resources and Prospects. By Hon. R. C. McCormick. With map, 8vow
paper.    *....  s.........            e..  0 0    e       5
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XINIFIF  (Wm.)  Mechanical'Drawing.  A  Text-Book
of Geometrical Drawing for the use of Mechanics and
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are familiarly explained; the Practical Problems are arranged, from the most simple to the more complex, and
in their description technicalities are avoided as much
as possible.  With illustrations for Drawing Plans, Sections, and Elevations of Buildings and Machinery; an
Introduction to Isometrical Drawing, and an Essay on
Linear Perspective and Shadows. Illustrated with over
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Architect.   Seventh Edition.  With an Appendix on
the Theory and Application of Colors. 1 vol. 8vo,
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WILLIAMiSON.  Practical Tables in. Meteorology and
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POPE. Modern Practice of the Electric Telegraph. For
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MINIFIE (Wm.)  Geometrical Drawing.  Abridged from
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7




D. VAX NOSTRAND'S PUBLIOATION&
PIERCE (Prof. Benj.) System of Analytical Mechanics.
Physical and Celestial Mechanics, by Benjamin Pierce,
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in four systems of Analytical Mechanics, Celestial Mechanics, Potential Physics, and Analytic Morphology.
x vol. 4to, cloth...........o................... $1o.oo
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PLY.IPTON.  The Blow-Pipe; a System of Instruction in
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Examination of Metallic Combinations.  Second  edition, with an appendix and a copious index.  By Geo.
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1 vol. 12mo, cloth.................... 2oo
POOK  (S. M.)  Method  of Comparing  the  Lines  and
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mere swinging of an axe."-O- h ronicle, Portsmout i, N.. H.
ROGE$RS (H. D.)  Geology of Pennsylvania.  A  complete
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Boards.... O....  O.......................                    30.
8




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SUBMARINE BLASTING IN BOSTON HARBOR,
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PLATTNER'S B23LOW-PIPE ANALYSIS. A Complete
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SPHERICAL A$STROINOIY. By F. Brunnow, Ph. Dr.
Translated  by the Author fiom  the Second German
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STILLMAN  (Paul).   Steam  Engine Indicator, and the Improved Manometer Steam  and Vacuum  Gauges-their
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author. The language of the author, the diagrams, and the scientific mode of treatment
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Boston Post.
SWEET (S. H.)  Special Report on Coal; showing its Distribution, Classification, and cost delivered over different
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Sweet.  With maps, i vol. 8vo, cloth............               3
WILLIT.5MSON.   Practical Tables  in Meteorology and
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" After thoroughly demonstrating the efficiency of the screw, Mr. Walker proceeds to
point out the various other points to be attended to in order to secure an efficient man-ofwar, and eulogi'zes throughout the readiness of the British Admiralty to test every noveity calculated to give satisfactory results.      e * e Commander Walker's book contains an immense amount of concise practical data, and every item of information recorded fully proves that the various points bearing *upon it havye been well consld-Iod
provioutly to expressing an opinion." —Loto.JiinsI Journal
iu




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U. S. Navy.  New  and  revised  edition.   1 vol. 8vo,
cloth...................................... $1 00
WEISBACH  (Julius).  Principles of the Mechanics of Machinery and  Engineering.  By Dr. Julius Weisbach, of
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WHILDEiN (J. K.)  On the Strength of Materials used in
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and torsional elasticity."-Anmerican Artisan.
WHITNEY  (J. P.)  Colorado, in the  United  States  of
America. Schedule of Ores contributed by sundry
persons to the Paris Universal Exposition of 1867, with
some Infornmtion about the Region and its Resources.
By J. P. Whitney, of Boston, Commissioner from   the
Territory.  Pamphlet 8vo, with maps. London, 1867.                  25
Silver Mining Regions of Colorado, with some account of the different processes now being introduced
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Whitney.   12mo, paper...................... 25
WILLIAMISON  (R. S.)  On the Use of the Barometer on
Surveys and  Reconnaissances.  Part I. Meteorology in
its connection with Hypsometry.   Part IH. Barometric
Hypsometry.  By R. S. Williamson, Bvt. Lieut.-Col.
U. S. A., ~Major Corps of Engineers.  With Illustrative Table: and  Engravings.   Paper No. 15, Professional Papers, Corps of Engineers.   I vol. 4to, cloth. I5.oo
*                      T f~~~~~I




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R OEBLING  (J. A.)   Long  and  Short Span  Railway
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CLAtIE4AY   (T. C.)   Description  of the  Iron  Railway
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cloth.   ~~~~~~~           ~    ~~~0~~~~~                  7.50
TUI'ITER  (P.)   A  Treatise  on  Roll-Turning  for the
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and wood-cuts. I vol. 8vo, text, and fol. vol. Plates,
cloth......................................
ISHERWOOD  (B. F.) Engineering Precedents for Steam
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PEET. Manual of Inorganic Chemistry for Students.
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I 2mo, cloth............................. $2.0o
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TRIC TELEGRAPH.  By Robert Sabine, C.E. zd
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GLYNN (J.)  Treatise on the Power of Water, as applied
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ELUIBER.  A Handy Book for the Calculation of Strains
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William Humber.  I 2mo, fully illustrated, cloth...  2. 5
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VANl BUREN. Investigations of Formulas, for the strength
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JOYNSON.  Designing and Construction of Machine
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HOW   TO  BEC03IE A  SUCCESSFUL  ENGINEER.
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NAYE3R.  Lecture Notes on Physics.' By Alfred M.
Mayer, Ph. D. 8vo, cloth.......0.............oo
A TREATISE ON THE RICHARDS STEAM-ENGINE
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