cutter, which revolves at a moderate speed over a slide, carrying a
pair of centres, between which the turned up piece of pinion wire is
placed. The slide is now pushed up to and under the cutter, and in
its passage as much of a cut is taken as is desirable; in drawing
back the slide the fresh cut space passes under a flat piece of thin
steel, screwed on the frame, and set at a slight angle to the axis of
the centres. On moving the slide towards the cutter for a fresh cut,
the steel plate takes the last cut, and in passing by it the pinion
is turned just as much as the angularity of the plate, which must be
just one leaf. By this very clever device the division is effected
without an index plate. This process, however, is not good enough for
work intended to be very accurate--the pinion wire not being always, or
indeed rarely correctly divided, the original error will be perpetuated
in all the subsequent processes. These are all milled, with oil or soda
water for a lubricator, and it follows that the speed of the cutter is
regulated to get the greatest cut without dulling the tool. When dull,
however, the mill is sharpened on the _face_ of the cutting tooth by
means of small grinders of iron, using Arkansas oil-stone dust for the
first grinding, and giving the necessary delicacy of the edge by means
of crocus, or sharp, followed, when fine work is needed, by rouge.
It is necessary that this care should be taken, for if the edge is
left coarse it will become speedily dulled, and leave a very unequal
and rough surface on the cut of the pinion, which in the subsequent
grinding gives rise to error in shape and size. The pinions, thus cut
to gauge, are dried in sawdust, hardened, and tempered; the staff and
pivots are now turned up to size, and then pass to the polishers. In
the factory they are finished by means of what are called _Wig-Wags_,
which it may be interesting to the reader to have a general description
of.
Two Vs are arranged as centres, the pinion is placed between them,
the circular parts resting in each V, but free to turn on its own
axis. Immediately above the Vs is a frame on which a slide, carrying
the polisher, may traverse--generally about two inches. This slide is
movable vertically so as to accommodate itself to the pinion; attached
to the slide is a connection which leads to a vertical lever, which
is put in motion from a crank on the counter shaft. The grinding is
effected by bringing the grinder, charged with oil-stone dust in oil,
in one of the spaces of the pinion, which, of course, is so arranged
as to bring it parallel and central with the grinder. The power being
applied, the slide takes a very rapid reciprocatory motion, and the
face of the grinder, so charged, rapidly reduces the uneven surface
left by the cutter to what is called the _gray_.
The form of this grinder must be as perfect as the cutters, and the
care taken to get the requisite parallelism is in equal proportion,
and in all the best polishers is planed up while in its position. The
grinder is composed of tin and lead, with sometimes a slight admixture
of antimony, rolled to an even thickness, cut off in suitable lengths,
and then mounted in the carrier of the Wig-Wag to be planed up to
shape. There are too many minute adjustments in the machine to render a
full description in this article admissible. It is large compared with
the work it has to perform, but it is very admirably made, as indeed
all the tools are, in the American factories.
The polishing of the leaves is the next step, and this is effected by
means precisely the same as grinding. In each stage the pinions are
thoroughly cleansed before entering on another. The polisher is made
precisely like the grinder; but instead of oil-stone dust, crocus mixed
with oil is substituted. Owing to the less cutting quality of the
material used, the polisher loses its form sooner than the grinder,
and has to be more frequently reshaped. In very fine work the crocus
is succeeded by fine well-levigated rouge to bring up that jet black
polish, which is considered a mark of quality by chronometer and watch
makers.
With the exception of turning up the staff and pivots, all the work
hitherto described has been expended on the leaves--a very tedious
process, yet done, when the tools and materials are in proper order,
with marvellous rapidity; but tedious as these have been, there are two
others quite as much so before the leaves are finished.
The ends are to be faced--they must be flat (that is a true plane) and
receive the same finish that the leaves took, and is effected by the
wig-wag; only the pinion revolves between centres, at a high speed, the
grinder being brought up to the turned face. Two motions operate--one
rectilinear, the other circular--the result being a compound motion
which prevents the grinder from touching the same spot twice in
succession. To effect this more surely, the operator gives the grinder
a slight vibratory vertical motion. The polishing of the two faces is
effected in the same manner as the grinding; in all cases the cutting
face of the grinders and polishers being kept in a plane perpendicular
to the axis of the pinion, both vertical and horizontal.
The staff and pivots being in the same condition they came from the
lathe, the next step is to grind and polish them. Before, however, we
treat on this process, it may not be amiss to give the general watch
repairer a process by which the facing may be done on a small scale.
As a rule, when the watch repairer has to replace a pinion he selects
one from the material dealer, finished in the leaves, but not on the
ends or faces. The following operations are simple, and any one may
finish these faces with little trouble. Having turned up your pivots
and squared down the face of the leaves with the turning tool, grind
it in the lathe by means of a ring of metal, the inside diameter being
somewhat larger than the diameter of the staff. This ring is held
between two centres, thus allowing it a vibratory motion, so that
when it comes up to the face it accommodates itself to its plane, and
thus has no tendency to force it out of a true flat; the ring, being
larger than the staff or pivot, admits a small lateral motion, enough
to effect a continuous change of surface. The same little tool may be
used for polishing by substituting another polisher and using crocus
and rouge. For the repairer, perhaps on general work the rouge would
be superfluous. Vienna lime, used with a little slip of boxwood,
brings up a very fine and brilliant polish, and in replacing new work
in an injured time-piece, the steel may always be polished with great
rapidity by using the lime on the gray surface left from the oil-stone
dust; being quickly done and affording a very handsome finish.
To resume the consideration of the pinion, the last stage is the
polishing of the circular portions. Here again the wig-wag is the
most useful tool, but it operates somewhat differently, for the
grinder or polisher is pressed down by the finger of the operator,
the pinion being held between the centres of a small lathe attached
to the wig-wag; the staff is first ground and polished as the leaves
have been before, and this is the last operation performed with the
pinion between centres. From this stage it is chucked in a lathe very
peculiarly fitted, the mandrel being hollow; and in it is fitted what
is called a pump-centre, which is movable in direction of the axis of
the mandrel, and capable of being securely fastened at any desired
point. On the nose of the mandrel is secured a hollow steel chuck,
the two sides of which have been filed out, thus leaving an open
space between the end of the pump-centre and the end of the chuck. On
this end a small steel plate, extremely thin, is fastened by means
of shellac, and a hole drilled in the plate capable of taking in the
chamfer on the shoulder of the pivot. The pump-centre being drawn
back, the pinion is introduced into the chuck, the pivot placed in the
hole in the steel plate, and the pump centre is drawn forward until
it forces the chamfer to fill the hole; the pivot projecting from
the chuck is now ready for all the grinding and polishing processes.
Here the wig-wag steps in again, and from the delicacy of the pivots
is modified to suit the case; this is done by having a polisher hung
in the wig-wag on centres, so it may revolve; when in operation one
side of the polisher rests on the pivot, the other on a ruby placed
in a screw, and which screw enables the operative to insure the
parallelism of the pivot. The ends of the pivots are next rounded off
and finished in another set of tools. The pinion is now ready for use,
assuming it to be of the proper gauge. In the American watches the
scape and fourth wheels are generally staked on the staff pinch tight;
the third and centre are staked on the pinion leaves, a rebate having
been turned down on the ends, the wheel set on the shoulder, and the
projecting ends of the leaves riveted down. This has not been designed
as an exhaustive article on pinions; it is merely intended to open the
subject as pursued in the factories. There is much more to be said; and
the various processes on the small scale, as performed by the Swiss
and English, together with their tools, will bear more than a general
description, as they are applicable at any watch bench.
The subject will be continued, in the effort to give a full and useful
article.
New Three-Pin Escapement.
A contributor to the _London Horological Journal_ gives the following
description of his invention:
“The merit of this escapement is in a newly invented escape-wheel
which is self-locking and requires no banking pins; the pallets are
curved inside the impulse and outside the locking, to work with the
curved points of the teeth of the wheel; being made of gold the wheel
will go without oil. From its form it has the power of double impulse
and double locking with the lever. The first takes place at the
discharge of the escapement, the second does not act unless the watch
receives a sudden motion, and then the pin or pallet in the roller
strikes lightly on the lever, when the propellant power drives it back
again. The balance passes through two turns before the second locking
takes place, and is formed so as to be able to take up the lever,
and the watch soon rights itself, and its time will not be affected.
Another advantage is, that the lever is made of a flat piece of steel,
as I have introduced a gold stud to receive the ruby impulse stone,
which is made to adjust easily so as to bring the escapement to the
closest geometrical accuracy. By its formation this ruby guides the
impulse to the external edge of the roller notch. These advantages,
and its simplicity, render it suitable to the best chronometer
watches.”
A FEW years ago, in 1859 or ’60, Mr. Peabody, a very talented
gentleman of this city, patented a three-pin escapement that performed
extremely well. A full description of his patent and plan is not at
hand, but we will endeavor to give it to our readers in our next issue.
English Opinion of American Watch Manufacture.
In the London circle of Horologists, more attention is paid to the
scientific departments than the mercantile; but for all that, a Mr.
Henry Ganney has held forth before the “British Horological Institute,”
on “American Watch Manufacture.” Though an Englishman, with English
prejudices, he certainly gives a very fair and impartial statement
of the subject; yet he views it almost entirely in the money-making
aspect. He gives all the credit deserved to American enterprise and
ingenuity, and yet there is a certain sense of a drawback. He had
before him samples of machine work; among others, to quote, “several
movements made by the British Watch Company, which flourished and
failed about twenty-five years ago; these were machine-made, and the
perfection and completeness of the machinery they used for producing
these frames has not been equalled, I believe, in America; several
machines being used there to accomplish what was begun and completed by
one here.”
Mr. Ganney is right in his statement, but the example given by the
British Watch Company was the rock seen by the American navigators. One
tool, for facing off, truing up, drilling, depthing, and doing all the
work on the pillar plate, having cost, before completion, some three
thousand pounds sterling, and from its very complexity being utterly
inefficient--worse than useless. In the very inception of the American
watch manufacture a similar mistake was almost made. Experience and
sound reasoning proved, however, that a multiplicity of operations in
any one machine rendered it entirely too complex, the adjustments too
numerous, and the work totally worthless. We shall in another number
refer again to Mr. Ganney’s lecture, and perhaps give some beamings of
light on the early history of the American watch manufacture, derived
from personal observation at the time.
Correspondence.
EDITORS HOROLOGICAL JOURNAL:
I received a Prospectus a few days ago advising me of your
contemplated existence. I could hardly believe the fact; “the news
was too good to be true.” However, I shall take it for granted, for I
cannot see why somebody has not before had the enterprise to launch
out in the periodical line on subjects connected with Horology, the
field being so extensive and the want so severely felt. Enclosed
I send you the subscription price; in this much I have accepted
your invitation, but I also enclose some few lines on a subject not
particularly practical or theoretical, but very near the truth, and
may perhaps give you a view of our wants.
To tell the “plain unvarnished truth,” I am a watch repairer, located
in a small country village, with a decent stock of tools and a
moderate trade. In all this I am no exception; so I write this in
the name of all who are similarly situated. Isolated as we are, we
(the country village watch repairers) have few means to improve our
knowledge of the trade, but work on the same old principles learned
when we were boys and apprentices, and of better and more expeditious
ways of doing our work we are entirely oblivious. True, our friends
of the Hebraic persuasion, who, angel like, bring us face to face
with the outer horological world by selling us material and tools,
occasionally present to our benumbed vision something new, such as a
Swiss lathe, or lathes used in the factories; but of what use are they
to us? We purchase one; well, on the bench it may be an ornament, but
for use, drilling large holes is the height of our ambition. We have
not the time to learn by self-experience all the boasted usefulness
and capacities of the tool; so we go back to our old verge or Jacot
lathe when we have to put in a pivot or a new staff. We may know all
about the escapement and be able to detect the cause of any trouble
with it, but we have no knowledge of the latest modes of repairing the
injury when it is discovered, and this knowledge is what I hope to
find in your journal. I live in a section where the general class of
work is of a very low grade, even the old verge being very common. Our
stock of material has to be heavy in proportion to our trade, and then
once in a while we are compelled to send our work to the city, some
sixty miles distant, in consequence of not being able to do it, either
from a lack of the material or want of a proper tool. To all intents
and purposes we remain as stationary as the oyster. Not only do we
have these vexations, but the ignorance of the public at large as to
the treatment of their time-keepers is a fruitful source of annoyance;
we are often charged with fraudulent practices, and a certain degree
of caution is observed by more than the most ignorant. Thus, a few
days ago, a stalwart son of the Green Isle made his appearance in
front of the counter, and, projecting in front of our optics a huge
English double-cased verge watch, spoke in almost dramatic tones:
“Plase, sir, av’ ye could make me ticker here go, sir?”
Answering in the affirmative we reached for the silent “ticker.” He
drew back with alarm.
“Bedad, an’ ye’ll not stale a morsle frae this?”
“Well, but let me see the watch.”
“An’ will ye let me eyes be on yes all the time?”
“Yes.”
“An’ yes’ll not stale a jewil?”
“No.”
“Thin, there it is.”
On looking at the movement the verge was found broken, the injury
explained, and the price given. He decided on the repairs being done,
but said, “Give me the watch now and when ye gets the thing fixed its
meself will come and git it and pay yes.”
“But we cannot repair the watch without having it.”
“Faith, thin, ye’ll not have it; ye’ll be taking something frae it.”
Now, this is an extreme case of ignorance, pardonable, perhaps, in
this instance, but the public embraces multitudes just as ignorant
where an allowance cannot be made. I do not expect the JOURNAL to
reach such cases, or to influence the general mass, but my hope is
that it will, by raising the general self-respect and tone of the
repairers, indirectly elevate the respect felt for them by the public
at large.
But I am writing too long and rambling a letter. I wish to express my
hearty wishes for your prosperity. And, in conclusion, will you allow
me to express a hope that you will give us the knowledge we need--that
is, post us up on the minutiæ of repairing in the latest styles, the
newest processes devised, and, above all, give us an article on the
lathe and its uses?
Yours truly,
W. L. C.
We have the pleasure to give our correspondent the assurance that an
expert will contribute to our next number an article interesting as
well as valuable in instruction as to the use of the lathe.
Eclipse of the Sun.
The approaching total eclipse of the sun, on the 7th of August next,
is exciting much interest. The obscuration first occurs in latitude
39° 53´ 3´´ north, longitude 138° 37´ 4´´ west--Washington being the
meridian. The first totality is on the Pacific coast of Siberia, at
sunrise, in lat. 52° 41´ 9´´ north, and long. 165° 26´ 4´´ west. The
eclipse is total at noon in Alaska, lat. 61° 46´ 9´´ north, and long.
68° 4´ 6´´ west. The line of the total eclipse now runs south-easterly,
grazing the coast near Sitka, thence north into British America; then
entering the United States, near the head of Milk River, long. 30° W.;
thence through the south-west corner of Minnesota, diagonally through
Iowa, crosses the Mississippi at Burlington; thence through Illinois,
a little north of Springfield, crosses the Ohio river at or near
Louisville, Ky., passes through the south-west corner of West Virginia,
through North Carolina, just south of Raleigh, ending on the Atlantic
coast at sunset, just north of Beaufort, N. C., in lat. 31° 15´ 2´´
north, and long. 9° 36´ 6´´ east. The line thus described will be that
of totality, only partial in any other part of the United States.
The United States Government is, or has been, establishing a meridian
line at Springfield, partly to make observations on this coming
eclipse, and with the further view of determining a standard of
surveyed lines--all of the Government surveys in Illinois having been
geodetic. Professor Austin, of the Smithsonian Institute, is in charge
of the work, aided by an able corps of assistants.
Diamond-Cutting.
At the Great Exhibition in Paris, in a part of the park contiguous to
the Netherland section, M. Coster, of Amsterdam, has erected a building
wherein all the processes of diamond-cutting are carried on.
The first rough shaping of the more important facets of the brilliants
is here seen performed by the workman, who operates on two diamonds at
once, by bruising each against the other, angle against angle. The dust
that falls from the stones is preserved for the subsequent processes
of grinding and polishing those facets that distinguish the many-sided
brilliant from the dull, original crystal of the diamond. It is used,
mingled with oil, on a flat iron disk, set revolving with vast rapidity
by steam-power, the stone itself being held upon this disk or wheel by
a tool to which it is attached by a mass of fusible metallic alloy,
into which the stone is skilfully inserted. Skill of eye and hand, only
attainable by great practice, is needed for this work; but a skill not
less exact is needed for another process, which may here be seen in
daily operation--the process of cleavage. The diamond, when a blow is
struck on an edged tool placed parallel to one of the octahedral faces
of the crystal, readily splits in that direction. But to recognize the
precise direction on the complex and generally rounded form of the
diamond crystal; to cut a little notch by means of a knife edge of
diamonds formed of one of the slices cleaved from a crystal, and to
cut that notch exactly the right spot; then to plant the steel knife
that is to split the diamond precisely in the right position; finally,
with a smart blow, to effect the cleavage so as to separate neither
too large nor small a portion of the stone--these various steps in the
process need great skill and judgment, and present to the observer
the interesting spectacle which a handicraft dependent on experience
of hand and eye always affords. But Mr. Coster’s exhibition has other
objects of interest. For the first time, we may see here, side by side,
the diamond with the minerals that accompany it in the river beds of
Brazil; and there are even examples in which crystals of diamonds
are included within a mass of quartz crystals, which have all the
appearance of having been formed simultaneously with deposits of the
diamond.
The different districts of Rio and of Bahia are thus represented--the
former producing a confusedly crystallized sort of diamond termed
“bort,” and the latter an opaque black variety; both these kinds being
found associated with the crystallized diamonds used for jewelry.
Though useful in state of powder, the black carbon and “bort” are
incapable of being cut as a jewel.--_“Maskelyne’s Report,” Great
Exhibition._
The Alloys of Aluminum with Copper.
When Sir Humphrey Davy announced the fact that soda, lime, potash,
magnesia, and the other alkalies were but oxides of a metallic base, it
would have been deemed chimerical to have supposed that the discoveries
he made by the expensive aid of the battery would at later date become
of really commercial value. He did obtain both sodium and potassium
in the metallic state. The substances in this form were new to the
chemical world, still more strange to the popular. So new was it to the
chemists, that, on a globule of the reduced sodium being presented to
a very distinguished chemist, he, with some enthusiasm, examined it;
and, admitting the fact of its being a metal, exclaimed, “how heavy
it is!”--when the real fact was that its specific gravity was less
than water; the expression was the result of the general preconceived
opinion that a high specific gravity was a test of a metallic body. It
was reserved for a French chemist, Henry St. Claire Deville, to utilize
the metal sodium, and that, too, in such a manner that the demand
aroused attention to its production;--demand will inevitably bring a
supply.
The original reduction was made by Davy, by means of the voltaic
battery. After it had been proved that these bases were really metals
capable of reduction, chemistry brought all its resources to bear on
the problem, and they were produced by other methods than the battery.
All the processes adopted, however, were too expensive and laborious,
involving an extraordinary amount of complicated manipulations with but
inadequate results. The metal sodium, which is the immediate subject of
our inquiry, long remained an object simply of curiosity or experiment
in the laboratory.
The methods of reducing the metal have of late years been so simplified
that, to quote Prof. Chas. A. Joy in the _Journal of Applied
Chemistry_: “A few years ago a pound of this metal could not have been
purchased for two hundred dollars, and even at that price there were
few manufacturers hardy enough to take the order. At the present time
it can be readily manufactured for seventy-five cents, if not for fifty
cents a pound; and the probabilities are that we shall soon be able to
obtain it for one-quarter of a dollar.”