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   Home - Steel Making - Categories - Manufacturing and the Economy of Machinery

Manufacturing

Accumulating Power
20. Whenever the work to be done requires more force for its ...

Of Copying By Casting
105. The art of casting, by pouring substances in a fluid st...

Exerting Forces Too Great For Human Power And Executing Operations Too Delicate For Human Touch
56. It requires some skill and a considerable apparatus to e...

Of Raw Materials
210. Although the cost of any article may be reduced in its ...

On The Effect Of Machinery In Reducing The Demand For Labour
404. One of the objections most frequently urged against mac...

Of Price As Measured By Money
201. The money price at which an article sells furnishes us ...

On Combinations Of Masters Against The Public
376. A species of combination occasionally takes place among...

Of Copying With Altered Dimensions
147. Of the pentagraph. This mode of copying is chiefly used ...

Copying With Elongation
140. In this species of copying there exists but little rese...

On The Causes And Consequences Of Large Factories
263. On examining the analysis which has been given in chapt...

Economy Of The Materials Employed
77. The precision with which all operations by machinery are ...

Proper Circumstances For The Application Of Machinery
329. The first object of machinery, the chief cause of its e...

Extending The Time Of Action Of Forces
45. This is one of the most common and most useful of the em...

On A New System Of Manufacturing
305. A most erroneous and unfortunate opinion prevails among...

Of Copying By Punching
133. This mode of copying consists in driving a steel punch ...

Distinction Between Making And Manufacturing
163. The economical principles which regulate the application...

Saving Time In Natural Operations
47. The process of tanning will furnish us with a striking i...

Increase And Diminution Of Velocity
32. The fatigue produced on the muscles of the human frame d...

On The Method Of Observing Manufacturies
160. Having now reviewed the mechanical principles which reg...

Of Copying
82. The two last-mentioned sources of excellence in the work ...



Proper Circumstances For The Application Of Machinery






Category: On the domestic and political economy of manufactures

329. The first object of machinery, the chief cause of its
extensive utility, is the perfection and the cheap production of
the articles which it is intended to make. Whenever it is
required to produce a great multitude of things, all of exactly
the same kind, the proper time has arrived for the construction
of tools or machines by which they may be manufactured. If only a
few pairs of cotton stockings should be required, it would be an
absurd waste of time, and of capital, to construct a
stocking-frame to weave them, when, for a few pence, four steel
wires can be procured by which they may be knit. If, on the other
hand, many thousand pairs were wanted, the time employed, and the
expense incurred in constructing a stocking-frame, would be more
than repaid by the saving of time in making that large number of
stockings. The same principle is applicable to the copying of
letters: if three or four copies only are required, the pen and
the human hand furnish the cheapest means of obtaining them; if
hundreds are called for, lithography may be brought to our
assistance; but if hundreds of thousands are wanted, the
machinery of a printing establishment supplies the most
economical method of accomplishing the object.

330. There are, however, many cases in which machines or
tools must be made, in which economical production is not the
most important object. Whenever it is required to produce a few
articles parts of machinery, for instance, which must be executed
with the most rigid accuracy or be perfectly alike--it is nearly
impossible to fulfil this condition, even with the aid of the
most skilful hands: and it becomes necessary to make tools
expressly for the purpose, although those tools should, as
frequently happens, cost more in constructing than the things
they are destined to make.

331. Another instance of the just application of machinery,
even at an increased expense, arises where the shortness of time
in which the article is produced, has an important influence on
its value. In the publication of our daily newspapers, it
frequently happens that the debates in the Houses of Parliament
are carried on to three and four o'clock in the morning, that is.
to within a very few hours of the time for the publication of the
paper. The speeches must be taken down by reporters, conveyed by
them to the establishment of the newspaper, perhaps at the
distance of one or two miles, transcribed by them in the office,
set up by the compositor, the press corrected, and the paper be
printed off and distributed, before the public can read them.
Some of these journals have a circulation of from five to ten
thousand daily. Supposing four thousand to be wanted, and that
they could be printed only at the rate of five hundred per hour
upon one side of the paper, (which was the greatest number two
journeymen and a boy could take off by the old hand presses),
sixteen hours would be required for printing the complete
edition; and the news conveyed to the purchasers of the latest
portion of the impression, would be out of date before they could
receive it. To obviate this difficulty, it was often necessary to
set up the paper in duplicate, and sometimes, when late, in
triplicate: but the improvements in the printing machines have
been so great, that four thousand copies are now printed on one
side in an hour.

332. The establishment of 'The Times' newspaper is an
example, on a large scale, of a manufactory in which the division
of labour, both mental and bodily, is admirably illustrated, and
in which also the effect of domestic economy is well exemplified.
It is scarcely imagined by the thousands who read that paper in
various quarters of the globe, what a scene of organized activity
the factory presents during the whole night, or what a quantity
of talent and mechanical skill is put in action for their
amusement and information. (1*) Nearly a hundred persons are
employed in this establishment; and, during the session of
Parliament, at least twelve reporters are constantly attending
the Houses of Commons and Lords; each in his turn retiring, after
about an hour's work, to translate into ordinary writing, the
speech he has just heard and noted in shorthand. In the meantime
fifty compositors are constantly at work, some of whom have
already set up the beginning, whilst others are committing to
type the yet undried manuscript of the continuation of a speech,
whose middle portion is travelling to the office in the pocket of
the hasty reporter, and whose eloquent conclusion is, perhaps, at
that very moment, making the walls of St Stephen's vibrate with
the applause of its hearers. These congregated types, as fast as
they are composed, are passed in portions to other hands; till at
last the scattered fragments of the debate, forming, when united
with the ordinary matter, eight-and-forty columns, reappear in
regular order on the platform of the printing-press. The hand of
man is now too slow for the demands of his curiosity, but the
power of steam comes to his assistance. Ink is rapidly supplied
to the moving types, by the most perfect mechanism; four
attendants incessantly introduce the edges of large sheets of
white paper to the junction of two great rollers, which seem to
devour them with unsated appetite; other rollers convey them to
the type already inked, and having brought them into rapid and
successive contact, redeliver them to four other assistants,
completely printed by the almost momentary touch. Thus, in one
hour, four thousand sheets of paper are printed on one side; and
an impression of twelve thousand copies, from above three hundred
thousand moveable pieces of metal, is produced for the public in
six hours.

333. The effect of machinery in printing other periodical
publications, and of due economy in distributing them, is so
important for the interests of knowledge, that it is worth
examining by what means it is possible to produce them at the
small price at which they are sold. 'Chambers' Journal', which is
published at Edinburgh, and sold at three halfpence a number,
will furnish an example. Soon after its commencement in 1832, the
sale in Scotland reached 30,000, and in order to supply the
demand in London it was reprinted; but on account of the expense
of 'composition' it was found that this plan would not produce
any profit, and the London edition was about to be given up, when
it occurred to the proprietor to stereotype it at Edinburgh, and
cast two copies of the plates. This is now done about three weeks
before the day of publication--one set of plates being sent up
to London by the mail, an impression is printed off by steam: the
London agent has then time to send packages by the cheapest
conveyances to several of the large towns, and other copies go
through the booksellers' parcels to all the smaller towns. Thus a
great saving is effected in the outlay of capital, and 20,000
copies are conveyed from London, as a centre, to all parts of
England, whilst there is no difficulty in completing imperfect
sets, nor any waste from printing more than the public demand.

334. The conveyance of letters is another case, in which the
importance of saving time would allow of great expense in any new
machinery for its accomplishment. There is a natural limit to the
speed of horses, which even the greatest improvements in the
breed, aided by an increased perfection in our roads, can never
surpass; and from which, perhaps, we are at present not very
remote. When we reflect upon the great expense of time and money
which the last refinements of a theory or an art usually require,
it is not unreasonable to suppose that the period has arrived in
which the substitution of machinery for such purposes ought to be
tried.

335. The post bag despatched every evening by the mail to one
of our largest cities, Bristol, usually weighs less than a
hundred pounds. Now, the first reflection which naturally
presents itself is, that, in order to transport these letters a
hundred and twenty miles, a coach and apparatus, weighing above
thirty hundredweight, are put in motion, and also conveyed over
the same space. (2*)

It is obvious that, amongst the conditions of machinery for
accomplishing such an object, it would be desirable to reduce the
weight of matter to be conveyed along with the letters: it would
also be desirable to reduce the velocity of the animal power
employed; because the faster a horse is driven, the less weight
he can draw. Amongst the variety of contrivances which might be
imagined for this purpose, we will mention one, which, although
by no means free from objections, fulfils some of the prescribed
conditions; and it is not a purely theoretical speculation, since
some few experiments have been made upon it, though on an
extremely limited scale.

336. Let us imagine a series of high pillars erected at
frequent intervals, perhaps every hundred feet, and as nearly as
possible in a straight line between two post towns. An iron or
steel wire must be stretched over proper supports, fixed on each
of these pillars, and terminating at the end of every three or
five miles, as may be found expedient, in a very strong support,
by which it may be stretched. At each of these latter points a
man ought to reside in a small stationhouse. A narrow cylindrical
tin case, to contain the letters, might be suspended by two
wheels rolling upon this wire; the cases being so constructed as
to enable the wheels to pass unimpeded by the fixed supports of
the wire. An endless wire of much smaller size must pass over two
drums, one at each end of the station. This wire should be
supported on rollers, fixed to the supports of the great wire,
and at a short distance below it. There would thus be two
branches of the smaller wire always accompanying the larger one;
and the attendant at either station, by turning the drum, might
cause them to move with great velocity in opposite directions. In
order to convey the cylinder which contains the letters, it would
only be necessary to attach it by a string, or by a catch, to
either of the branches of the endless wire. Thus it would be
conveyed speedily to the next station, where it would be removed
by the attendant to the commencement of the next wire, and so
forwarded. It is unnecessary to enter into the details which
this, or any similar plan, would require. The difficulties are
obvious; but if: these could be overcome, it would present many
advantages besides velocity; for if an attendant resided at each
station, the additional expense of having two or three deliveries
of letters every day, and even of sending expresses at any
moment, would be comparatively trifling; nor is it impossible
that the stretched wire might itself be available for a species
of telegraphic communication yet more rapid.

Perhaps if the steeples of churches, properly selected, were
made use of, connecting them by a few intermediate stations with
some great central building, as, for instance, with the top of St
Paul's; and if a similar apparatus were placed on the top of each
steeple, with a man to work it during the day, it might be
possible to diminish the expense of the two-penny post, and make
deliveries every half hour over the greater part of the
metropolis.

337. The power of steam, however, bids fair almost to rival
the velocity of these contrivances; and the fitness of its
application to the purposes of conveyance, particularly where
great rapidity is required, begins now to be generally admitted.
The following extract from the Report of the Committee of the
House of Commons on steamcarriages, explains clearly its various
advantages:

Perhaps one of the principal advantages resulting from the use of
steam, will be, that it may be employed as cheaply at a quick as
at a slow rate; 'this is one of the advantages over horse labour.
which becomes more and more expensive as the speed is increased.
There is every reason to expect, that in the end the rate of
travelling by steam will be much quicker than the utmost speed of
travelling by horses; in short, the safety to travellers will
become the limit to speed.' In horse-draught the opposite result
takes place; 'in all cases horses lose power of draught in a much
greater proportion than they gain speed, and hence the work they
do becomes more expensive as they go quicker.'

Without increase of cost, then, we shall obtain a power which
will insure a rapidity of internal communication far beyond the
utmost speed of horses in draught; and although the performance
of these carriages may not have hitherto attained this point,
when once it has been established, that at equal speed we can use
steam more cheaply in draught than horses, we may fairly
anticipate that every day's increased experience in the
management of the engines, will induce greater skill, greater
confidence, and greater speed.

The cheapness of the conveyance will probably be, for some
time, a secondary consideration. If, at present, it can be used
as cheaply as horse power, the competition with the former modes
of conveyance will first take place as to speed. When once the
superiority of steam-carriages shall have been fully established,
competition will induce economy in the cost of working them. The
evidence, however, of Mr Macneill, shewing the greater
efficiency, with diminished expenditure of fuel, by locomotive
engines on railwavs, convinces the committee, that experience
will soon teach a better construction of the engines, and a less
costly mode of generating the requisite supply of steam.

Nor are the advantages of steam-power confined to the greater
velocitv attained, or to its greater cheapness than
horse-draught. In the latter, danger is increased, in as large a
proportion as expense, by greater speed. In steam-power, on the
contrary, 'there is no danger of being run away with, and that of
being overturned is greatly diminished. It is difficult to
control four such horses as can draw a heavy carriage ten miles
per hour, in case they are frightened, or choose to run away; and
for quick travelling they must be kept in that state of courage,
that they are always inclined for running away, particularly down
hills, and at sharp turns of the road. In steam, however, there
is little corresponding danger, being perfectly controllable, and
capable of exerting its power in reverse in going down hills.,
Every witness examined has given the fullest and most
satisfactory evidence of the perfect control which the conductor
has over the movement of the carriage. With the slightest
exertion it can be stopped or turned, under circumstances where
horses would be totally unmanageable.

338. Another instance may be mentioned in which the object to
be obtained is so important, that although it might be rarely
wanted, yet machinery for that purpose would justify considerable
expense. A vessel to contain men, and to be navigated at some
distance below the surface of the sea, would, in many
circumstances, be almost invaluable. Such a vessel, evidently,
could not be propelled by any engine requiring the aid of fire.
If, however, by condensing air into a liquid, and carrying it in
that state, a propelling power could be procured sufficient for
moving the vessel through a considerable space, the expense would
scarcely render its occasional employment impossible.(3*)

339. Slide of Alpnach. Amongst the forests which flank many
of the lofty mountains of Switzerland, some of the finest timber
is found in positions almost inaccessible. The expense of roads,
even if it were possible to make them in such situations, would
prevent the inhabitants from deriving any advantages from these
almost inexhaustible supplies. Placed by nature at a considerable
elevation above the spot at which they can be made use of, they
are precisely in fit circumstances for the application of
machinery to their removal; and the inhabitants avail themselves
of the force of gravity to relieve them from some portion of this
labour. The inclined planes which they have established in
various forests, by which the timber has been sent down to the
water courses, have excited the admiration of every traveller;
and in addition to the merit of simplicity, the construction
these slides requires scarcely anything beyond the material which
grows upon the spot.

Of all these specimens of carpentry, the Slide of Alpnach was
the most considerable, from its great length, and from the almost
inaccessible position from which it descended. The following
account of it is taken from Gilbert's Annalen, 1819, which is
translated in the second volume of Brewster's Journal:

For many centuries, the rugged flanks and the deep gorges of
Mount Pilatus were covered with impenetrable forests; which were
permitted to grow and to perish, without being of the least
utility to man, till a foreigner, who had been conducted into
their wild recesses in the pursuit of the chamois, directed the
attention of several Swiss gentlemen to the extent and
superiority of the timber. The most skilful individuals, however,
considered it quite impracticable to avail themselves of such
inaccessible stores. It was not till the end of 1816, that M.
Rupp, and three Swiss gentlemen, entertaining more sanguine
hopes, purchased a certain extent of the forests, and began the
construction of the slide, which was completed in the spring of
1818.

The Slide of Alpnach is formed entirely of about 25,000 large
pine trees, deprived of their bark, and united together in a very
ingenious manner, without the aid of iron. It occupied about 160
workmen during eighteen months, and cost nearly 100,000 francs,
or L4,250. It is about three leagues, or 44,000 English feet
long, and terminates in the Lake of Lucerne. It has the form of a
trough, about six feet broad, and from three to six feet deep.
Its bottom is formed of three trees, the middle one of which has
a groove cut out in the direction of its length, for receiving
small rills of water, which are conducted into it from various
places, for the purpose of diminishing the friction. The whole of
the slide is sustained by about 2,000 supports; and in many
places it is attached, in a very ingenious manner, to the rugged
precipices of granite.

The direction of the slide is sometimes straight, and
sometimes zig-zag, with an inclination of from 10 degrees to 18
degrees. It is often carried along the sides of hills and the
flanks of precipitous rocks, and sometimes passes over their
summits. Occasionally it goes under ground, and at other times it
is conducted over the deep gorges by scaffoldings 120 feet in
height.

The boldness which characterizes this work, the sagacity and
skill displayed in all its arrangements, have excited the wonder
of every person who has seen it. Before any step could be taken
in its erection, it was necessary to cut several thousand trees
to obtain a passage through the impenetrable thickets. All these
difficulties, however, were surmounted, and the engineer had at
last the satisfaction of seeing the trees descend from the
mountain with the rapidity of lightning. The larger pines, which
were about a hundred feet long, and ten inches thick at their
smaller extremity, ran through the space of three leagues, or
nearly nine miles, in two minutes and a half, and during their
descent, they appeared to be only a few feet in length.

The arrangements for this part of the operation were
extremely simple. From the lower end of the slide to the upper
end, where the trees were introduced, workmen were posted at
regular distances, and as soon as everything was ready, the
workman at the lower end of the slide cried out to the one above
him, 'Lachez' (let go). The cry was repeated from one to another.
and reached the top of the slide in three minutes. The workmen at
the top of the slide then cried out to the one below him, 'Il
vient' (it comes), and the tree was instantly launched down the
slide, preceded by the cry which was repeated from post to post.
As soon as the tree had reached thebottom, and plunged into the
lake, the cry of lachez was repeated as before, and a new tree
was launched in a similar manner. By these means a tree descended
every five or six minutes, provided no accident happened to the
slide, which sometimes took place, but which was instantly
repaired when it did.

In order to shew the enormous force which the trees acquired
from the great velocity of their descent, M. Rupp made
arrangements for causing some of the trees to spring from the
slide. They penetrated by their thickest extremities no less than
from eighteen to twenty-four feet into the earth; and one of the
trees having by accident struck against another, it instantly
cleft it through its whole length, as if it had been struck by
lightning.

After the trees had descended the slide, they were collected
into rafts upon the lake, and conducted to Lucerne. From thence
they descended the Reuss, then the Aar to near Brugg, afterwards
to Waldshut by the Rhine, then to Basle, and even to the sea when
it was necessary.

It is to be regretted that this magnificent structure no
longer exists, and that scarcely a trace of it is to be seen upon
the flanks of Mount Pilatus. Political circumstances having taken
away the principal source of demand for the timber, and no other
market having been found, the operation of cutting and
transporting the trees necessarily ceased.(4*)

Professor Playfair, who visited this singular work, states,
that six minutes was the usual time occupied in the descent of a
tree; but that in wet weather, it reached the lake in three
minutes.

NOTES:

1. The author of these pages, with one of his friends, was
recently induced to visit this most interesting establishment,
after midnight, during the progress of a very important debate.
The place was illuminated with gas, and was light as the day:
there was neither noise nor bustle; and the visitors were
received with such calm and polite attention, that they did not,
until afterwards, become sensible of the inconvenience which such
intruders, at a moment of the greatest pressure, must occasion,
nor reflect tha the tranquility which they admired, was the
result of intense and regulated occupation. But the effect of
such checks in the current of business will appear on
recollecting that, as four thousand newspapers are printed off on
one side within the hour, every minute is attended with a loss of
sixty-six impressions. The quarter of an hour, therefore, which
the stranger may think it not unreasonable to claim for the
gratification of his curiosity (and to him this time is but a
moment), may cause a failure in the delivery of a thousand
copies, and disappoint a proportionate number of expectant
readers, in some of our distant towns, to which the morning
papers are dispatched by the earliest and most rapid conveyances
of each day.

This note is inserted with the further and more general
purpose of calling the attention of those, especially foreigners,
who are desirous of inspecting our larger manufactories, to the
chief cause of the difficulty which frequently attends their
introduction. When the establishment is very extensive, and its
departments skilfully arranged, the exclusion of visitors arises,
not from any illiberal jealousy, nor, generally, from any desire
of concealment, which would, in most cases, be absurd, but from
the substantial inconvenience and loss of time, throughout an
entire series of well-combined operations, which must be
occasioned even by short and causual interruptions.

2. It is true that the transport of letters is not the only
object which this apparatus answers; but the transport of
passengers, which is a secondary object, does in fact put a limit
to the velocity of that of the letters, which is the primary one.

3. A proposal for such a vessel, and description of its
construction, by the author of this volume, may be found in the
Encyclopaedia Metropolitana, Art. Diving Bell.

4. The mines of Bolanos in Mexico are supplied with timber from
the adjacent mountains by a slide similar to that of Alpnach. It
was constructed by M. Floresi, a gentleman well acquainted with
Switzerland.





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Previous: On Contriving Machinery



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