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Monday, September 11, 2006

CHAPTER 1

Sources of the Advantages arising from Machinery and Manufactures

1. There exists, perhaps, no single circumstance which
distinguishes our country more remarkably from all others, than
the vast extent and perfection to which we have carried the
contrivance of tools and machines for forming those conveniences
of which so large a quantity is consumed by almost every class of
the community. The amount of patient thought, of repeated
experiment, of happy exertion of genius, by which our
manufactures have been created and carried to their present
excellence, is scarcely to be imagined. If we look around the
rooms we inhabit, or through those storehouses of every
convenience, of every luxury that man can desire, which deck the
crowded streets of our larger cities, we shall find in the
history of each article, of every fabric, a series of failures
which have gradually led the way to excellence; and we shall
notice, in the art of making even the most insignificant of them,
processes calculated to excite our admiration by their
simplicity, or to rivet our attention by their unlooked-for
results.

2. The accumulation of skill and science which has been
directed to diminish the difficulty of producing manufactured
goods, has not been beneficial to that country alone in which it
is concentrated; distant kingdoms have participated in its
advantages. The luxurious natives of the East,(1*) and the ruder
inhabitants of the African desert are alike indebted to our
looms. The produce of our factories has preceded even our most
enterprising travellers.(2*) The cotton of India is conveyed by
British ships round half our planet, to be woven by British skill
in the factories of Lancashire: it is again set in motion by
British capital; and, transported to the very plains whereon it
grew, is repurchased by the lords of the soil which gave it
birth, at a cheaper price than that at which their coarser
machinery enables them to manufacture it themselves.(3*)

3. The large proportion of the population of this country,
who are engaged in manufactures, appears from the following table
deduced from a statement in an Essay on the Distribution of
Wealth, by the Rev. R. Jones:

For every hundred persons employed in agriculture, there are:

Agriculturists Non-agriculturists

In Bengal 100 25
In Italy 100 31
In France 100 50
In England 100 200


The fact that the proportion of non-agricultural to
agricultural persons is continually increasing, appears both from
the Report of the Committee of the House of Commons upon
Manufacturers' Employment, July, 1830, and from the still later
evidence of the last census; from which document the annexed
table of the increase of population in our great manufacturing
towns, has been deduced.

Increase of population per cent

Names of places
1801-11 1811-21 1821-31 Total
Manchester 22 40 47 151
Glasgow 30 46 38 161
Liverpool(4*) 26 31 44 138
Nottingham 19 18 25 75
Birmingham 16 24 33 90
Great Britain 14.2 15.7 15.5 52.5


Thus, in three periods of ten years, during each of which the
general population of the country has increased about 15 per
cent, or about 52 per cent upon the whole period of thirty years,
the population of these towns has, on the average, increased 132
per cent. After this statement, there requires no further
argument to demonstrate the vast importance to the well-being of
this country, of making the interests of its manufacturers well
understood and attended to.

4. The advantages which are derived from machinery and
manufactures seem to arise principally from three sources: The
addition which they make to human power. The economy they produce
of human time. The conversion of substances apparently common and
worthless into valuable products.

5. Of additions to human power. With respect to the first of
these causes, the forces derived from wind, from water, and from
steam, present themselves to the mind of every one; these are, in
fact, additions to human power, and will be considered in a
future page: there are, however, other sources of its increase,
by which the animal force of the individual is itself made to act
with far greater than its unassisted power; and to these we shall
at present confine our observations.

The construction of palaces, of temples, and of tombs, seems
to have occupied the earliest attention of nations just entering
on the career of civilization; and the enormous blocks of stone
moved from their native repositories to minister to the grandeur
or piety of the builders, have remained to excite the
astonishment of their posterity, long after the purposes of many
of these records, as well as the names of their founders, have
been forgotten. The different degrees of force necessary to move
these ponderous masses, will have varied according to the
mechanical knowledge of the people employed in their transport;
and that the extent of power required for this purpose is widely
different under different circumstances, will appear from the
following experiment, which is related by M. Rondelet, Sur L'Art
de Batir. A block of squared stone was taken for the subject of
experiment:

1. Weight of stone 1080 lbs

2. In order to drag this stone along the floor of the quarry,
roughly chiselled, it required a force equal to 758 lbs

3. The same stone dragged over a floor of planks required 652 lbs

4. The same stone placed on a platform of wood, and dragged over
a floor of planks, required 606 lbs

5. After soaping the two surfaces of wood which slid over each
other, it required 182 lbs

6. The same stone was now placed upon rollers of three inches
diameter, when it required to put it in motion along the floor of
the quarry 34 lbs

7. To drag it by these rollers over a wooden floor 28 lbs

8. When the stone was mounted on a wooden platform, and the same
rollers placed between that and a plank floor, it required 22 lbs


From this experiment it results, that the force necessary to
move a stone along

Part of its weight

The roughly chiselled floor of its quarry is nearly 2/3
Along a wooden floor 3/5
By wood upon wood 5/9
If the wooden surfaces are soaped 1/6
With rollers on the floor of the quarry 1/32
On rollers on wood 1/40
On rollers between wood 1/50


At each increase of knowledge, as well as on the contrivance
of every new tool, human labour becomes abridged. The man who
contrived rollers, invented a tool by which his power was
quintupled. The workman who first suggested the employment of
soap or grease, was immediately enabled to move, without exerting
a greater effort, more than three times the weight he could
before.(5*)

6. The economy of human time is the next advantage of
machinery in manufactures. So extensive and important is this
effect, that we might, if we were inclined to generalize, embrace
almost all the advantages under this single head: but the
elucidation of principles of less extent will contribute more
readily to a knowledge of the subject; and, as numerous examples
will be presented to the reader in the ensuing pages, we shall
restrict our illustrations upon this point.

As an example of the economy of time, the use of gunpowder in
blasting rocks may be noticed. Several pounds of powder may be
purchased for a sum acquired by a few days' labour: yet when this
is employed for the purpose alluded to, effects are frequently
produced which could not, even with the best tools, be
accomplished by other means in less than many months.

The dimensions of one of the blocks of limestone extracted
from the quarries worked for the formation of the breakwater at
Plymouth were 26 1/2 ft long, 13 ft wide, and 16 ft deep. This
mass, containing above 4,800 cubic feet, and weighing about 400
tons, was blasted three times. Two charges of 50 lbs each were
successively exploded in a hole 13 feet deep, the bore being 3
inches at top and 2 1/2 inches at bottom: 100 lbs of powder were
afterwards exploded in the rent formed by those operations. Each
pound of gunpowder separated from the rock two tons of matter, or
nearly 4,500 times its own weight. The expense of the powder was
L 6, or nearly 7 1/2d. per lb: the boring occupied two men during
a day and a half, and cost about 9s.; and the value of the
produce was, at that time, about L 45.

7. The simple contrivance of tin tubes for speaking through,
communicating between different apartments, by which the
directions of the superintendent are instantly conveyed to the
remotest parts of an establishment, produces a considerable
economy of time. It is employed in the shops and manufactories in
London, and might with advantage be used in domestic
establishments, particularly in large houses, in conveying orders
from the nursery to the kitchen, or from the house to the stable.
Its convenience arises not merely from saving the servant or
workman useless journeys to receive directions, but from
relieving the master himself from that indisposition to give
trouble, which frequently induces him to forego a trifling want,
when he knows that his attendant must mount several flights of
stairs to ascertain his wishes, and, after descending, must mount
again to supply them. The distance to which such a mode of
communication can be extended, does not appear to have been
ascertained, and would be an interesting subject for enquiry.
Admitting it to be possible between London and Liverpool, about
seventeen minutes would elapse before the words spoken at one end
would reach the other extremity of the pipe.

8. The art of using the diamond for cutting glass has
undergone, within a few years, a very important improvement. A
glazier's apprentice, when using a diamond set in a conical
ferrule, as was always the practice about twenty years since,
found great difficulty in acquiring the art of using it with
certainty; and, at the end of a seven years' apprenticeship, many
were found but indifferently skilled in its employment. This
arose from the difficulty of finding the precise angle at which
the diamond cuts, and of guiding it along the glass at the proper
inclination when that angle is found. Almost the whole of the
time consumed and of the glass destroyed in acquiring the art of
cutting glass, may now be saved by the use of an improved tool.
The gem is set in a small piece of squared brass with its edges
nearly parallel to one side of the square. A person skilled in
its use now files away the brass on one side until, by trial, he
finds that the diamond will make a clean cut, when guided by
keeping this edge pressed against a ruler. The diamond and its
mounting are now attached to a stick like a pencil, by means of a
swivel allowing a small angular motion. Thus, even the beginner
at once applies the cutting edge at the proper angle, by pressing
the side of the brass against a ruler; and even though the part
he holds in his hand should deviate a little from the required
angle, it communicates no irregularity to the position of the
diamond, which rarely fails to do its office when thus employed.

The relative hardness of the diamond, in different
directions, is a singular fact. An experienced workman, on whose
judgement I can rely, informed me that he has seen a diamond
ground with diamond powder on a cast-iron mill for three hours
without its being at all worn, but that, on changing its
direction with respect to the grinding surface, the same edge was
ground away.

9. Employment of materials of little value. The skins used by
the goldbeater are produced from the offal of animals. The hoofs
of horses and cattle, and other horny refuse, are employed in the
production of the prussiate of potash, that beautiful, yellow,
crystallized salt, which is exhibited in the shops of some of our
chemists. The worn-out saucepans and tinware of our kitchens,
when beyond the reach of the tinker's art, are not utterly
worthless. We sometimes meet carts loaded with old tin kettles
and worn-out iron coal-skuttles traversing our streets. These
have not yet completed their useful course; the less corroded
parts are cut into strips, punched with small holes, and
varnished with a coarse black varnish for the use of the
trunk-maker, who protects the edges and angles of his boxes with
them; the remainder are conveyed to the manufacturing chemists in
the outskirts of the town, who employ them in combination with
pyroligneous acid, in making a black die for the use of calico
printers.

10. Of tools. The difference between a tool and a machine is
not capable of very precise distinction; nor is it necessary, in
a popular explanation of those terms, to limit very strictly
their acceptation. A tool is usually more simple than a machine;
it is generally used with the hand, whilst a machine is
frequently moved by animal or steam power. The simpler machines
are often merely one or more tools placed in a frame, and acted
on by a moving power. In pointing out the advantages of tools, we
shall commence with some of the simplest.

11. To arrange twenty thousand needles thrown promiscuously
into a box, mixed and entangled in every possible direction, in
such a form that they shall be all parallel to each other, would,
at first sight, appear a most tedious occupation; in fact, if
each needle were to be separated individually, many hours must be
consumed in the process. Yet this is an operation which must be
performed many times in the manufacture of needles; and it is
accomplished in a few minutes by a very simple tool; nothing more
being requisite than a small flat tray of sheet iron, slightly
concave at the bottom. In this the needles are placed, and shaken
in a peculiar manner, by throwing them up a very little, and
giving at the same time a slight longitudinal motion to the tray.
The shape of the needles assists their arrangement; for if two
needles cross each other (unless, which is exceedingly
improbable, they happen to be precisely balanced), they will,
when they fall on the bottom of the tray, tend to place
themselves side by side, and the hollow form of the tray assists
this disposition. As they have no projection in any part to
impede this tendency, or to entangle each other, they are, by
continually shaking, arranged lengthwise, in three or four
minutes. The direction of the shake is now changed, the needles
are but little thrown up, but the tray is shaken endways; the
result of which is, that in a minute or two the needles which
were previously arranged endways become heaped up in a wall, with
their ends against the extremity of the tray. They are then
removed, by hundreds at a time, with a broad iron spatula, on
which they are retained by the forefinger of the left hand. As
this parallel arrangement of the needles must be repeated many
times, if a cheap and expeditious method had not been devised,
the expense of the manufacture would have been considerably
enhanced.

12. Another process in the art of making needles furnishes an
example of one of the simplest contrivances which can come under
the denomination of a tool. After the needles have been arranged
in the manner just described, it is necessary to separate them
into two parcels, in order that their points may be all in one
direction. This is usually done by women and children. The
needles are placed sideways in a heap, on a table, in front of
each operator, just as they are arranged by the process above
described. From five to ten are rolled towards this person with
the forefinger of the left hand; this separates them a very small
space from each other, and each in its turn is pushed lengthwise
to the right or to the left, according to the direction of the
point. This is the usual process, and in it every needle passes
individually under the finger of the operator. A small alteration
expedites the process considerably: the child puts on the
forefinger of its right hand a small cloth cap or fingerstall,
and rolling out of the heap from six to twelve needles, he keeps
them down by the forefinger of the left hand, whilst he presses
the forefinger of the right hand gently against their ends: those
which have the points towards the right hand stick into the
fingerstall; and the child, removing the finger of the left hand,
slightly raises the needles sticking into the cloth, and then
pushes them towards the left side. Those needles which had their
eyes on the right hand do not stick into the finger cover, and
are pushed to the heap on the right side before the repetition of
this process. By means of this simple contrivance each movement
of the finger, from one side to the other, carries five or six
needles to their proper heap; whereas, in the former method,
frequently only one was moved, and rarely more than two or three
were transported at one movement to their place.

13. Various operations occur in the arts in which the
assistance of an additional hand would be a great convenience to
the workman, and in these cases tools or machines of the simplest
structure come to our aid: vices of different forms, in which the
material to be wrought is firmly grasped by screws, are of this
kind, and are used in almost every workshop; but a more striking
example may be found in the trade of the nail-maker.

Some kinds of nails, such as those used for defending the
soles of coarse shoes, called hobnails, require a particular form
of the head, which is made by the stroke of a die. The workman
holds one end of the rod of iron out of which he forms the nails
in his left hand; with his right hand he hammers the red-hot end
of it into a point, and cutting the proper length almost off,
bends it nearly at a right angle. He puts this into a hole in a
small stake-iron immediately under a hammer which is connected
with a treadle, and has a die sunk in its surface corresponding
to the intended form of the head; and having given one part of
the form to the head with the small hammer in his hand, he moves
the treadle with his foot, disengages the other hammer, and
completes the figure of the head; the returning stroke produced
by the movement of the treadle striking the finished nail out of
the hole in which it was retained. Without this substitution of
his foot for another hand, the workman would, probably, be
obliged to heat the nails twice over.

14. Another, though fortunately a less general substitution
of tools for human hands, is used to assist the labour of those
who are deprived by nature, or by accident, of some of their
limbs. Those who have had an opportunity of examining the
beautiful contrivances for the manufacture of shoes by machinery,
which we owe to the fertile invention of Mr Brunel, must have
noticed many instances in which the workmen were enabled to
execute their task with precision, although labouring under the
disadvantages of the loss of an arm or leg. A similar instance
occurs at Liverpool, in the Institution for the Blind, where a
machine is used by those afflicted with blindness, for weaving
sash-lines; it is said to have been the invention of a person
suffering under that calamity. Other examples might be mentioned
of contrivances for the use, the amusement, or the instruction of
the wealthier classes, who labour under the same natural
disadvantages. These triumphs of skill and ingenuity deserve a
double portion of our admiration when applied to mitigate the
severity of natural or accidental misfortune; when they supply
the rich with occupation and knowledge; when they relieve the
poor from the additional evils of poverty and want.

15. Division of the objects of machinery. There exists a
natural, although, in point of number, a very unequal division
amongst machines: they may be classed as; first, those which are
employed to produce power, and as, secondly, those which are
intended merely to transmit force and execute work. The first of
these divisions is of great importance, and is very limited in
the variety of its species, although some of those species
consist of numerous individuals.

Of that class of mechanical agents by which motion is
transmitted--the lever, the pulley, the wedge, and many others--
it has been demonstrated, that no power is gained by their use,
however combined. Whatever force is applied at one point can only
be exerted at some other, diminished by friction and other
incidental causes; and it has been further proved, that whatever
is gained in the rapidity of execution is compensated by the
necessity of exerting additional force. These two principles,
long since placed beyond the reach of doubt, cannot be too
constantly borne in mind. But in limiting our attempts to things
which are possible, we are still, as we hope to shew, possessed
of a field of inexhaustible research, and of advantages derived
from mechanical skill, which have but just begun to exercise
their influence on our arts, and may be pursued without limit
contributing to the improvement, the wealth, and the happiness of
our race.

16. Of those machines by which we produce power, it may be
observed, that although they are to us immense acquisitions, yet
in regard to two of the sources of this power--the force of wind
and of water--we merely make use of bodies in a state of motion
by nature; we change the directions of their movement in order to
render them subservient to our purposes, but we neither add to
nor diminish the quantity of motion in existence. When we expose
the sails of a windmill obliquely to the gale, we check the
velocity of a small portion of the atmosphere, and convert its
own rectilinear motion into one of rotation in the sails; we thus
change the direction of force, but we create no power. The same
may be observed with regard to the sails of a vessel; the
quantity of motion given by them is precisely the same as that
which is destroyed in the atmosphere. If we avail ourselves of a
descending stream to turn a water-wheel, we are appropriating a
power which nature may appear, at first sight, to be uselessly
and irrecoverably wasting, but which, upon due examination, we
shall find she is ever regaining by other processes. The fluid
which is falling from a higher to a lower level, carries with it
the velocity due to its revolution with the earth at a greater
distance from its centre. It will therefore accelerate, although
to an almost infinitesimal extent, the earth's daily rotation.
The sum of all these increments of velocity, arising from the
descent of all the falling waters on the earth's surface, would
in time become perceptible, did not nature, by the process of
evaporation, convey the waters back to their sources; and thus
again, by removing matter to a greater distance from the centre,
destroy the velocity generated by its previous approach.

17. The force of vapour is another fertile source of moving
power; but even in this case it cannot be maintained that power
is created. Water is converted into elastic vapour by the
combustion of fuel. The chemical changes which thus take place
are constantly increasing the atmosphere by large quantities of
carbonic acid and other gases noxious to animal life. The means
by which nature decomposes these elements, or reconverts them
into a solid form, are not sufficiently known: but if the end
could be accomplished by mechanical force, it is almost certain
that the power necessary to produce it would at least equal that
which was generated by the original combustion. Man, therefore,
does not create power; but, availing himself of his knowledge of
nature's mysteries, he applies his talents to diverting a small
and limited portion of her energies to his own wants: and,
whether he employs the regulated action of steam, or the more
rapid and tremendous effects of gunpowder, he is only producing
on a small scale compositions and decompositions which nature is
incessantly at work in reversing, for the restoration of that
equilibrium which we cannot doubt is constantly maintained
throughout even the remotest limits of our system. The operations
of man participate in the character of their author; they are
diminutive, but energetic during the short period of their
existence: whilst those of nature, acting over vast spaces, and
unlimited by time, are ever pursuing their silent and resistless
career.

18. In stating the broad principle, that all combinations of
mechanical art can only augment the force communicated to the
machine at the expense of the time employed in producing the
effect, it might, perhaps, be imagined, that the assistance
derived from such contrivances is small. This is, however, by no
means the case: since the almost unlimited variety they afford,
enables us to exert to the greatest advantage whatever force we
employ. There is, it is true, a limit beyond which it is
impossible to reduce the power necessary to produce any given
effect, but it very seldom happens that the methods first
employed at all approach that limit. In dividing the knotted root
of a tree for fuel, how very different will be the time consumed,
according to the nature of the tool made use of! The hatchet, or
the adze, will divide it into small parts, but will consume a
large portion of the workman's time. The saw will answer the same
purpose more quickly and more effectually. This, in its turn, is
superseded by the wedge, which rends it in a still shorter time.
If the circumstances are favourable, and the workman skilful, the
time and expense may be still further reduced by the use of a
small quantity of gunpowder exploded in holes judiciously placed
in the block.

19. When a mass of matter is to be removed a certain force
must be expended; and upon the proper economy of this force the
price of transport will depend. A country must, however, have
reached a high degree of civilization before it will have
approached the limit of this economy. The cotton of Java is
conveyed in junks to the coast of China; but from the seed not
being previously separated, three-quarters of the weight thus
carried is not cotton. This might, perhaps, be justified in Java
by the want of machinery to separate the seed, or by the relative
cost of the operation in the two countries. But the cotton
itself, as packed by the Chinese, occupies three times the bulk
of an equal quantity shipped by Europeans for their own markets.
Thus the freight of a given quantity of cotton costs the Chinese
nearly twelve times the price to which, by a proper attention to
mechanical methods, it might be reduced. *

NOTES:

1. 'The Bandana handkerchiefs manufactured at Glasgow have long
superseded the genuine ones, and are now committed in large
quantities both by the natives and Chines.' Crawford's Indian
Archipelago, vol. iii, p. 505.

2. 'Captain Clapperton, when on a visit at the court of the
Sultan Bello, states, that provisionswere regularly sent me from
the sultan's table on pewter dishes with the London stamp; and I
even had a piece of meat served up on a white wash-hand basin of
English manufacture.' Clapperton's Journey, p. 88.

3. At Calicut, in the East Indies (whence the cotton cloth caled
calico derivesits name), the price of labour is one-seventh of
that in England, yet the market is supplied from British looms.

4. Liverpool, though not itself a manufacturing town, has been
placed in this list, from its connection with Manchester, of
which it is the port.

5. So sensible are the effects of grease in diminishing friction,
that the drivers of sledges in Amsterdam, on which heavy goodsare
transported, cary in their hand a rope soaked in tallow, which
they thrown down from time to time before the sledge, in order
that, by passing over the rope, it may become greased.