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EXEMPLARS ABRIDGED FROM MR. BABBAGE'S "ECONOMY OF MACHINERY AND
MANUFACTURES."
_Voyage of Manufacture._--The produce of our factories has preceded even
our most enterprising travellers. Captain Clapperton saw at the court of
the Sultan Bello, pewter dishes with the London stamp, and had at the
royal table a piece of meat served up on a white wash-hand basin of
English manufacture. 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.
At Calicut, in the East Indies (whence the cotton cloth called calico
derives its name) the price of labour is one-seventh of that in England,
yet the market is supplied from British looms.
_Additions to human power._--The force necessary to move a stone along
the roughly-chiselled floor of its quarry is nearly two-thirds of its
weight; to move it along a wooden floor, three-fifths; by wood upon
wood, five-ninths; if the wooden surfaces are soaped, one-sixth; if
rollers are used on the floor of the quarry, it requires
one-thirty-second part of the weight; if they roll on wood,
one-fortieth; and if they roll between wood, one-fiftieth of its weight.
At each increase of knowledge, as well as on the contrivance of every
new tool, human labour becomes abridged.
_Economy of time._--Several pounds of gunpowder may be purchased for a
sum acquired by a few days' labour; yet, when this is employed in
blasting rocks, effects are produced which could not, even with the best
tools, be accomplished by other means in less than many months.
_Economy of Materials._--The worn-out saucepans and tin-ware 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-scuttles 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 trunkmaker, who protects the edges and angles
of his box with them; the remainder are conveyed to the manufacturing
chemists in the outskirts of the town, who employ them, in conjunction
with pyroligneous acid, in making a black dye for the use of calico
printers.
_Accumulation of Power_ arises from lifting a weight and then allowing
it to fall. A man, even with a heavy hammer, might strike repeated blows
upon the head of a pile without producing any effect. But if he raises a
much heavier hammer to a much greater height, its fall, though far less
frequently repeated, will produce the desired effect.
_Regulating Power._--A contrivance for regulating the effect of
machinery consists in a vane or a fly, of little weight, but presenting
a large surface. This revolves rapidly, and soon acquires an uniform
rate, which it cannot greatly exceed, because any addition to its
velocity produces a much greater addition to the resistance it meets
with from the air. The interval between the strokes on the bell of a
clock is regulated by this means; and the fly is so contrived, that this
interval may be altered by presenting the arms of it more or less
obliquely to the direction in which they move. This kind of fly or vane
is generally used in the smaller kinds of mechanism, and, unlike the
heavy fly, it is a destroyer instead of a preserver of force. It is the
regulator used in musical boxes, and in almost all mechanical toys.
_Increase and Diminution of Velocity._--Twisting the fibres of wool by
the fingers would be a most tedious operation; in the common
spinning-wheel the velocity of the foot is moderate; but, by a very
simple contrivance, that of the thread is most rapid. A piece of cat-gut
passing round a large wheel, and then round a small spindle, effects
this change. The small balls of sewing cotton, so cheap and so
beautifully wound, are formed by a machine on the same principle, and
but a few steps more complicated. The common smoke-jack is an instrument
in which the velocity communicated is too great for the purpose
required, and it is transmitted through wheels which reduce it to a more
moderate rate.
_Extending the Time of Action in Forces._--The half-minute which we
daily devote to the winding up of our watches is an exertion of labour
almost insensible; yet, by the aid of a few wheels its effect is spread
over the whole twenty-four hours. Another familiar illustration may be
noticed in our domestic furniture: the common jack by which our meat is
roasted, is a contrivance to enable the cook in a few minutes to exert a
force which the machine retails out during the succeeding hour in
turning the loaded spit.
_Saving Time in natural Operations._--The process of tanning formerly
occupied from six months to two years; this time being apparently
required in order to allow the tanning matter to penetrate into the
interior of a thick hide. The improved process consists in placing the
hides with the solution of tan in close vessels, and then exhausting the
air. The consequence of this is to withdraw any air which might be
contained in the pores of the hides, and to employ the pressure of the
atmosphere to aid capillary attraction in forcing the tan into the
interior of the skins. The effect of the additional force thus brought
into action can be equal only to one atmosphere, but a further
improvement has been made: the vessel containing the hides is, after
exhaustion, filled up with a solution of tan; a small additional
quantity is then injected with a forcing-pump. By these means any degree
of pressure may be given which the containing vessel is capable of
supporting, and it has been found that, by employing such a method, the
thickest hides may be tanned in six weeks or two months.
_Printing from Wooden Blocks._--A block of box-wood is, in this
instance, the substance out of which the pattern is formed: the design
being sketched upon it, the workman cuts away with sharp tools every
part except the lines to be represented in the impression. This is
exactly the reverse of the process of engraving on copper, in which
every line to be represented is cut away. The ink, instead of filling
the cavities cut in the wood, is spread upon the surface which remains,
and is thence transferred to the paper.
_Making and Manufacturing._--There exists a considerable difference
between the terms _making_ and _manufacturing_. The former refers to the
production of _a small_, the latter to that of _a very large number of
individuals_; and the difference is well illustrated in the evidence
given before the Committee of the House of Commons on the Export of
Tools and Machinery. On that occasion Mr. Maudslay stated, that he had
been applied to by the Navy Board to make iron tanks for ships, and that
he was rather unwilling to do so, as he considered it to be out of his
line of business; however, he undertook to make one as a trial. The
holes for the rivets were punched by hand-punching with presses, and the
1,680 holes which each tank required cost seven shillings. The Navy
Board who required a large number, proposed that he should supply forty
tanks a week for many months. The magnitude of the order made it worth
while to commence _manufacturer_, and to make tools for the express
business. Mr. Maudslay therefore offered, if the Board would give him an
order for two thousand tanks, to supply them at the rate of eighty per
week. The order was given: he made the tools, by which the expense of
punching the rivet-holes of each tank was reduced from seven shillings
to ninepence; he supplied ninety-eight tanks a week for six months, and
the price charged for each was reduced from seventeen pounds to fifteen.
_Brass-plate Coal Merchants._--In the recent examination by the
committee of the House of Commons into the state of the Coal Trade, it
appears that five-sixths of the London public is supplied by a class of
middle-men who are called in the trade "Brass-plate Coal Merchants:"
these consist principally of merchants' clerks, gentlemen's servants,
and others, who have no wharfs, but merely give their orders to some
true coal-merchant, who sends in the coals from his wharf. The
brass-plate coal merchant, of course, receives a commission for his
agency, which is just so much loss to the consumer.
_Raw Materials._--Gold-leaf consists of a portion of the metal beaten
out to so great a degree of thinness, as to allow a greenish-blue light
to be transmitted through its pores. About 400 square inches of this are
sold, in the form of a small book, containing twenty-five leaves of gold
for 1_s_. 6_d_. In this case, the raw material, or gold, is worth rather
less than two-thirds of the manufactured article. In the case of silver
leaf, the labour considerably exceeds the value of the material. A book
of fifty leaves, covering above 1,000 square inches is sold for 1_s_.
3_d_.
The quantity of labour applied to Venetian gold chains is very great,
but incomparably less than that which is applied to some of the
manufactures of iron. In the case of the smallest Venetian chain the
value of the labour is not above thirty times that of the gold. The
pendulum spring of a watch, which governs the vibrations of the balance,
costs at the retail price twopence, and weighs fifteen one-hundredths of
a grain, whilst the retail price of a pound of the best iron, the raw
material out of which fifty thousand such springs are made, is exactly
the sum of twopence.
In France bar-iron, made as it usually is with charcoal, costs three
times the price of the cast-iron out of which it is made; whilst in
England, where it is usually made with coke, the cost is only twice the
price of cast-iron.
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