K. Opening caused by the removal of part of the floor of the small
cupboard.
L. A box which serves to conceal an opening in the floor of the large
cupboard, made to facilitate the first position; and which also serves
as a seat for the third position.
M. A similar box to receive the toes of the player in the first
position.
N. The inner chest filling up part of the trunk.
O. The space behind the drawer.
P Q. The false back turning on a joint at Q.
R. Part of the partition formed of cloth stretched tight, which is
carried up by the false back to form the opening between the chambers.
S. The opening between the chambers.
T. The opening connecting the trunk and chest, which is partly
concealed by the false back.
U. Panel which is slipt aside to admit the player.
* * * * *
Various pieces of mechanism of wonderful ingenuity have been
constructed for the purposes of drawing and writing. One of these,
invented by M. Le Droz, the son of the celebrated Droz of Chaux le
Fonds, has been described by Mr. Collinson. The figure was the size
of life. It held in its hand a metallic style, and when a spring was
touched, so as to release a detent, the figure immediately began to
draw upon a card of Dutch vellum previously laid under its hand.
After the drawing was executed on the first card, the figure rested.
Other five cards were then put in, in succession, and upon these it
delineated in the same manner different subjects. On the first card it
drew “elegant portraits and likenesses of the king and queen facing
each other;” and Mr. Collinson remarks, that it was curious to observe
with what precision the figure lifted up its pencil in its transition
from one point of the drawing to another, without making the slightest
mistake.
M. Maillardet has executed an automaton which both writes and draws.
The figure of a boy kneeling on one knee holds a pencil in his hand.
When the figure begins to work, an attendant dips the pencil in ink,
and adjusts the drawing-paper upon a brass tablet. Upon touching a
spring, the figure proceeds to write, and when the line is finished,
its hand returns to dot and stroke the letters when necessary. In this
manner it executes four beautiful pieces of writing in French and
English, and three landscapes, all of which occupy about one hour.
One of the most popular pieces of mechanism which we have seen is the
magician constructed by M. Maillardet for the purpose of answering
certain given questions. A figure dressed like a magician appears
seated at the bottom of a wall, holding a wand in one hand, and a book
in the other. A number of questions ready prepared are inscribed on
oval medallions, and the spectator takes any of these which he chooses,
and to which he wishes an answer, and having placed it in a drawer
ready to receive it, the drawer shuts with a spring till the answer
is returned. The magician then rises from his seat, bows his head,
describes circles with his wand, and, consulting the book as if in deep
thought, he lifts it towards his face. Having thus appeared to ponder
over the proposed question, he raises his wand, and striking with
it the wall above his head, two folding-doors fly open, and display
an appropriate answer to the question. The doors again close, the
magician resumes his original position, and the drawer opens to return
the medallion. There are twenty of these medallions, all containing
different questions, to which the magician returns the most suitable
and striking answers. The medallions are thin plates of brass of an
elliptical form, exactly resembling each other. Some of the medallions
have a question inscribed on each side, both of which the magician
answers in succession. If the drawer is shut without a medallion being
put into it, or if a _blank_ medallion, viz., one which contains no
question, is put into the drawer, the magician rises, consults his
book, shakes his head, and resumes his seat. The folding-doors remain
shut, and the drawer is returned empty. If two medallions are put into
the drawer together, an answer is returned only to the lower one. When
the machinery is wound up, the movements continue about an hour, during
which time about fifty questions may be answered. The method by which
the different medallions acted upon the machinery, so as to produce the
proper answers to the questions which they bore, was of course kept a
secret by the inventor, but it was discovered by Mr. Brockedon, who
has kindly communicated to me an account of it.
Upon examining the edge of the circular medallions, Mr. Brockedon
discovered in all of them, except the blanks, a small hole almost
concealed by the milling. This led Mr. Brockedon to examine the
receptacle for the medallion in the drawer, and he observed the edge
of a pin flush with the edge of the receptacle, whence the pin was
protruded by the machine into the holes in the medallion, the depth of
the hole regulating the answer. In order to prove this, Mr. B. cut a
slip from a cedar pencil small enough to enter easily the holes in the
medallion, if he found them to be of different depths. As the blank
medallions had no hole, and produced only a shake of the magician’s
head, Mr. B. took a medallion with a question, and having plugged the
hole with a bit of cedar, he cut it flush, and having placed it in the
receptacle, the conjuror shook his head, and thus bore testimony to the
truth of Mr. Brockedon’s discovery.
M. Maillardet has constructed various other automata, representing
insects and other animals. One of these was a spider entirely made of
steel, which exhibited all the movements of the animal. It ran on the
surface of a table during three minutes, and to prevent it from running
off, its course always tended towards the centre of the table. He
constructed likewise a caterpillar, a lizard, a mouse, and a serpent.
The serpent crawls about in every direction, opens its mouth, hisses,
and darts out its tongue.
Ingenious and beautiful as all these pieces of mechanism are, and
surprising as their effects appear even to scientific spectators, the
principal object of their inventors was to astonish and amuse the
public. We should form an erroneous judgment, however, if we suppose
that this was the only result of the ingenuity which they displayed.
The passion for automatic exhibitions, which characterized the 18th
century, gave rise to the most ingenious mechanical devices, and
introduced among the higher orders of artists habits of nice and
accurate execution in the formation of the most delicate pieces of
machinery. The same combination of the mechanical powers which made the
spider crawl, or which waved the tiny rod of the magician, contributed
in future years to purposes of higher import. Those wheels and pinions,
which almost eluded our senses by their minuteness, re-appeared in the
stupendous mechanism of our spinning-machines and our steam-engines.
The elements of the tumbling-puppet were revived in the chronometer,
which now conducts our navy through the ocean; and the shapeless wheel
which directed the hand of the drawing automaton has served, in the
present age, to guide the movements of the tambouring engine. Those
mechanical wonders, which in one century enriched only the conjuror
who used them, contributed in another to augment the wealth of the
nation; and those automatic toys, which once amused the vulgar, are now
employed in extending the power and promoting the civilization of our
species. In whatever way, indeed, the power of genius may invent or
combine, and to whatever low or even ludicrous purposes that invention
or combination may be originally applied, society receives a gift which
it can never lose; and though the value of the seed may not be at once
recognized, and though it may lie long unproductive in the ungenial
till of human knowledge, it will some time or other evolve its germ,
and yield to mankind its natural and abundant harvest.
Did the limits of so popular a volume as this ought to be permit it, I
should have proceeded to give a general description of some of these
extraordinary pieces of machinery, the construction and effects of
which never fail to strike the spectator with surprise. This, however,
would lead me into a field too extensive, and I shall therefore confine
myself to a notice of three very remarkable pieces of mechanism which
are at present very little known to the general reader, viz., the
tambouring machine of Mr. Duncan, the statue-turning machine of Mr.
Watt, and the calculating machinery of Mr. Babbage.
The tambouring of muslins, or the art of producing upon them ornamental
flowers and figures, has been long known and practised in Britain
as well as in other countries; but it was not long before the year
1790, that it became an object of general manufacture in the west of
Scotland, where it was chiefly carried on. At first it was under the
direction of foreigners; but their aid was not long necessary, and
it speedily extended to such a degree as to occupy, either wholly or
partially, more than 20,000 females. Many of these labourers lived
in the neighbourhood of Glasgow, which was the chief seat of the
manufacture; but others were scattered through every part of Scotland,
and supplied by agents with work and money. In Glasgow, a tambourer
of ordinary skill could not in general earn more than five or six
shillings a week by constant application; but to a labouring artisan,
who had several daughters, even these low wages formed a source of
great wealth. At the age of five years, a child capable of handling a
needle was devoted to tambouring, even though it could not earn more
than a shilling or two in a week; and the consequence of this was, that
female children were taken from school, and rendered totally unfit for
any social or domestic duty. The tambouring population, was, therefore,
of the worst kind, and it must have been regarded as a blessing rather
than as a calamity, when the work which they performed was entrusted to
regular machinery.
Mr. John Duncan of Glasgow, the inventor of the tambouring machinery,
was one of those unfortunate individuals who benefit their species
without benefiting themselves, and who died in the meridian of life,
the victim of poverty and of national ingratitude. He conceived the
idea of bringing into action a great number of needles at the same
time, in order to shorten the process by manual labour; but he at
first was perplexed about the diversification of the pattern. This
difficulty, however, he soon surmounted by employing two forces at
right angles to each other, which gave him a new force in the direction
of the diagonal of the parallelogram, whose sides were formed by the
original forces. His first machine was very imperfect; but after two
years’ study, he formed a company, at whose expense six improved
machines were put in action, and who secured the invention by a patent.
At this time the idea of rendering the machine automatic had scarcely
occurred to him; but he afterwards succeeded in accomplishing this
great object, and the tambouring machines were placed under the
surveillance of a steam-engine. Another patent was taken for these
improvements. The reader who desires to have a minute account of these
improvements, and of the various parts of the machinery, will be amply
gratified by perusing the inventor’s own account of the machinery
in the article CHAINWORK in the Edinburgh Encyclopædia. At present
it will be sufficient to state, that the muslin to be tamboured was
suspended vertically in a frame, which was capable of being moved both
in a vertical and a horizontal direction. Sixty or more needles lying
horizontally occupied a frame in front of the muslin web. Each of these
working needles, as they are called, was attended by a feeding-needle,
which, by a circular motion round the working-needle, lodged upon the
stem of the latter the loop of the thread. The sixty needles then
penetrated the web, and, in order that they might return again without
injuring the fabric, the barb or eye of the needle, which resembled the
barb of a fishing-hook, was shut by a slider. The muslin web then took
a new position by means of the machinery that gave it its horizontal
and vertical motion, so that the sixty needles penetrated it, at their
next movement, at another point of the figure or flower. This operation
went on till sixty flowers were completed. The web was then slightly
wound up, that the needles might be opposite that part of it on which
they were to work another row of flowers.
The flowers were generally at an inch distance, and the rows were
placed so that the flowers formed what are called diamonds. There were
seventy-two rows of flowers in a yard, so that in every square yard
there were nearly 4000 flowers, and in every piece of ten yards long
40,000. The number of loops or stitches in a flower varied with the
pattern, but on an average there were about thirty. Hence the number
of stitches in a yard were 120,000, and the number in a piece is
1,200,000. The average work done in a week by one machine was fifteen
yards, or 60,000 flowers, or 1,800,000 stitches; and by comparing this
with the work done by one person with the hand, it appeared that the
machine enabled one person to do the work of twenty-four persons.
One of the most curious and important applications of machinery
to the arts which has been suggested in modern times, was made by
the late Mr. Watt, in the construction of a machine for copying or
reducing statues and sculpture of all kinds. The art of multiplying
busts and statues, by casts in plaster of Paris, has been the means
of diffusing a knowledge of this branch of the fine arts; but from
the fragile nature of the material, the copies thus produced were
unfit for exposure to the weather, and therefore ill calculated for
ornamenting public buildings, or for perpetuating the memory of public
achievements. A machine, therefore, which is capable of multiplying
the labours of the sculptor in the durable materials of marble or of
brass was a desideratum of the highest value, and one which could
have been expected only from a genius of the first order. During many
years Mr. Watt carried on his labours in secret, and he concealed
even his intention of constructing such a machine. After he had made
considerable progress in its execution, and had thought of securing
his invention by a patent, he learned that an ingenious individual
in his own neighbourhood had been long occupied in the same pursuit;
and Mr. Watt informed me that he had every reason to believe that
this gentleman was entirely ignorant of his labours. A proposal was
then made that the two inventors should combine their talents, and
secure the privilege by a joint patent; but Mr. Watt had experienced
so frequently the fatal operation of our patent laws, that he saw many
difficulties in the way of such an arrangement, and he was unwilling,
at his advanced age, to embark in a project so extensive, and which
seemed to require for its successful prosecution all the ardour and
ambition of a youthful mind. The scheme was therefore abandoned;
and such is the unfortunate operation of our patent laws, that the
circumstance of two individuals having made the same invention has
prevented both from bringing it to perfection, and conferring a great
practical benefit upon their species. The machine which Mr. Watt had
constructed had actually executed some excellent pieces of work. I
have seen in his house at Heathfield copies of basso-relievos, and
complete statues of a small size; and some of his friends have in their
possession other specimens of its performance.
Of all the machines which have been constructed in modern times,
the calculating-machine is doubtless the most extraordinary. Pieces
of mechanism for performing particular arithmetical operations have
been long ago constructed, but these bear no comparison either in
ingenuity or in magnitude to the grand design conceived and nearly
executed by Mr. Babbage. Great as the power of mechanism is known to
be, yet we venture to say, that many of the most intelligent of our
readers will scarcely admit it to be possible that astronomical and
navigation tables can be accurately computed by machinery; that the
machine can itself correct the errors which it may commit; and that
the results of its calculations, when absolutely free from error,
can be printed off, without the aid of human hands, or the operation
of human intelligence. All this, however, Mr. Babbage’s machine can
do; and as I have had the advantage of seeing it actually calculate,
and of studying its construction with Mr. Babbage himself, I am able
to make the above statement on personal observation. The calculating
machine now constructing under the superintendence of the inventor
has been executed at the expense of the British Government, and is
of course their property. It consists essentially of two parts; a
calculating part, and a printing part, both of which are necessary to
the fulfilment of Mr. Babbage’s views; for the whole advantage would be
lost if the computations made by the machine were copied by human hands
and transferred to types by the common process. The greater part of the
calculating machinery is already constructed, and exhibits workmanship
of such extraordinary skill and beauty, that nothing approaching to it
has been witnessed. In order to execute it, particularly those parts of
the apparatus which are dissimilar to any used in ordinary mechanical
constructions, tools and machinery of great expense and complexity have
been invented and constructed; and in many instances contrivances of
singular ingenuity have been resorted to which cannot fail to prove
extensively useful in various branches of the mechanical arts.
The drawings of this machinery, which form a large part of the work,
and on which all the contrivance has been bestowed, and all the
alterations made, cover upwards of 400 _square feet of surface_, and
are executed with extraordinary care and precision.
In so complex a piece of mechanism, in which interrupted motions are
propagated simultaneously along a great variety of trains of mechanism,
it might have been supposed that obstructions would arise, or even
incompatibilities occur, from the impracticability of foreseeing
all the possible combinations of the parts; but this doubt has been
entirely removed, by the constant employment of a system of mechanical
notation invented by Mr. Babbage, which places distinctly in view, at
every instant, the progress of motion through all the parts of this or
any other machine, and by writing down in tables the times required for
all the movements, this method renders it easy to avoid all risk of two
opposite actions arriving at the same instant at any part of the engine.
In the printing part of the machine less progress has been made in the
actual execution than in the calculating part. The cause of this is
the greater difficulty of its contrivance, not for transferring the
computations from the calculating part to the copper or other plate
destined to receive it, but for giving to the plate itself that number
and variety of movements which the forms adopted in printed tables may
call for in practice.
The practical object of the calculating engine is to compute and print
a great variety and extent of astronomical and navigation tables,
which could not be done without enormous intellectual and manual
labour, and which, even if executed by such labour, could not be
calculated with the requisite accuracy. Mathematicians, astronomers,
and navigators, do not require to be informed of the real value of such
tables; but it may be proper to state, for the information of others,
that _seventeen_ large folio volumes of logarithmic tables alone were
calculated, at an enormous expense, by the French Government; and that
the British Government regarded these tables to be of such national
value, that they proposed to the French Board of Longitude to print
an _abridgement_ of them at the joint expense of the two nations, and
offered to advance 5000_l._ for that purpose. Besides logarithmic
tables, Mr. Babbage’s machine will calculate tables of the powers
and products of numbers, and all astronomical tables for determining
the positions of the sun, moon, and planets; and the same mechanical
principles have enabled him to integrate innumerable equations of
finite differences, that is, when the equation of differences is given,
he can, by setting an engine, produce at the end of a given time
any distant term which may be required, or any succession of terms
commencing at a distant point.
Besides the cheapness and celerity with which this machine will perform
its work, the _absolute accuracy_ of the printed results deserves
especial notice. By peculiar contrivances, any small error produced by
accidental dust, or by any slight inaccuracy in one of the wheels, is
corrected as soon as it is transmitted to the next, and this is done
in such a manner as effectually to prevent any accumulation of small
errors from producing an erroneous figure in the result.
In order to convey some idea of this stupendous undertaking, we may
mention the effects produced by a small trial engine constructed by
the inventor, and by which he computed the following table from the
formula _x^2_ + _x_ + 41. The figures, as they were calculated by the
machine, were not exhibited to the eye as in sliding-rules and similar
instruments, but were actually presented to the eye on two opposite
sites of the machine, the number 383, for example, appearing in figures
before the person employed in copying.
_Table calculated by a small Trial Engine._
41 131 383 797 1373
43 151 421 853 1447
47 173 461 911 1523
53 197 503 971 1601
61 223 547 1033 1681
71 251 593 1097 1763
83 281 641 1163 1847
97 313 691 1231 1933
113 347 743 1301 2021
While the machine was occupied in calculating this table, a friend of
the inventor undertook to write down the numbers as they appeared.
In consequence of the copyist writing quickly, he rather more than
kept pace with the engine, but as soon as five figures appeared, the
machine was at least equal in speed to the writer. At another trial
_thirty-two_ numbers of the same table were calculated in the space of
_two minutes and thirty seconds_; and as these contained _eighty-two_
figures, the engine produced thirty-three figures every minute, or
more than one figure in every two seconds. On another occasion it
produced _forty-four_ figures per minute. This rate of computation
could be maintained for any length of time; and it is probable that few
writers are able to copy with equal speed for many hours together.
Some of that class of individuals who envy all great men, and deny all
great inventions, have ignorantly stated that Mr. Babbage’s invention
is not new. The same persons, had it suited their purpose, would
have maintained that the invention of spectacles was an anticipation
of the telescope; but even this is more true than the allegation
that the arithmetical machines of Pascal and others were the types
of Mr. Babbage’s engine. The object of these machines was entirely
different. Their highest functions were to perform the operations of
common arithmetic. Mr. Babbage’s engine, it is true, can perform these
operations also, and can extract the roots of numbers, and approximate
to the roots of equations, and even to their impossible roots. But
this is not its object. Its function, in contradistinction to that
of all other contrivances for calculating, is to embody in machinery
the method of differences, which has never before been done; and the
effects which it is capable of producing, and the works which in the
course of a few years we expect to see it execute, will place it at an
infinite distance from all other efforts of mechanical genius.[33]
[33] A popular account of this engine will be found in Mr. Babbage’s
interesting volume _On the Economy of Manufactures_, lately published.