CALCULATING ENGINES.
A COLLECTION OF PAPERS RELATING TO THEM;
LONDON:
by
L.F. Menebrea, of Turin, Officer of the Military Engineers
(From the Philosophical Magazine, Sept. 1848, p. 235.)
Much misapprehension having arisen as to the circumstances attending
the invention and construction of Mr. Babbage's Calculating Engines,
it is necessary to state from authority the facts relating to them.
In 1823, Mr. Babbage, who had previously invented an Engine for
calculating and printing tables by means of differences, undertook, at
the desire of the Government, to superintend the construction of such an
Engine. He bestowed his whole time upon the subject for many years,
refusing for that purpose other avocations which would have been attended
with considerable pecuniary advantage. During this period about 17, 000 [British Pounds]
had been expended by the Government in the construction of the Difference
Engine. A considerable part of this sum had from time to time been advanced
by Mr. Babbage for the payment of the workmen, and was of
course repaid; but it was never contemplated by either party that any
portion of this sum should be appropriated to Mr. Babbage himself, and
in truth not one single shilling of the money was in any shape whatever
received by Mr. Babbage for his invention, his time, or his services,
a fact which Sir Robert Peel admitted in the House of Commons in March
1843.
Early in 1833 the construction of this Engine was suspended on account
of some dissatisfaction with the workmen, which it is now unnecessary to
detail. It was expected that the interruption, which arose from circumstances
over which Mr. Babbage had no control, would be only temporary.
About twelve months after the progress of the Difference Engine had been
thus suspended, Mr. Babbage discovered a principle of an entirely new
order, the power of which over the most complicated arithmetical operations
seemed nearly unbounded. The invention of simpler mechanical means
for exacting the elementary operations of that Engine, now acquired far
greater importance than it had hitherto possessed.
In the Engine for calculating by differences, such simplifications affected
only about a hundred and twenty similar parts, while in the new,
or Analytical Engine, they might affect several thousand. The Difference
Engine might be constructed with more or less advantage, by employing
various mechanical modes for the operation of addition. The Analytical
Engine could not exist without inventing for it a method of mechanical
addition possessed of the utmost simplicity. In fact it was not until
upwards of twenty different modes for performing the operation of addition
had been designed and drawn, that the necessary degree of simplicity
required for the Analytical Engine was ultimately attained.
These new views acquired great additional importance from their
bearings upon the Difference Engine already partly executed for the
Government; for if such simplifications should be discovered, it might
happen that the Analytical Engine would execute with greater rapidity
the calculations for which the Difference Engine was intended; or that
the Difference Engine would itself be superseded by a far simpler mode
of construction.
Though these views might, perhaps, at that period, have appeared
visionary, they have subsequently been completely realized..
To have allowed the construction of the Difference Engine to be
resumed while these new views were withheld from the Government would
have been improper; yet the state of uncertainty in which those views were
then necessarily involved., rendered any written communication respecting
their probable bearing on that engine a matter of very great difficulty.
It therefore appeared to Mr. Babbage that the most straightforward
course was to ask for an interview with the head of the Government, and
to communicate to him the exact state of the case. Various circumstances
occurred to delay, and ultimately to prevent that interview.
From the year 1833 to the close of 1842, Mr. Babbage repeatedly
applied to the Government for its decision upon the subject. These ap-
plications were unavailing. Years of delay and anxiety followed each
other, impairing those energies which were now directed to the invention
of the Analytical Engine. This state of uncertainty had many injurious
effects. It prevented Mr. Babbage from entering into any engagement
with other Governments respecting the Analytical Engine, by which he
might have been enabled to employ a greater number of assistants, and thus
to have applied his faculties only to the highest departments of the subject,
instead of exhausting them on inferior objects, that might have been
executed with less fatigue by other heads. It also became necessary,
from motives of prudence, that the heavy expense incurred for this purpose
should be spread over a period of many years. This consideration naturally
caused a new source of anxiety and risk, arising from .the uncertain
tenure of human life and of human faculities, - a reflection ever present
to distract and torment the mind, and itself calculated to cause the fulfilment
of its own forebodings.
Amidst such distractions the author of the Analytical Engine has
steadily pursued his single purpose. The numberless misrepresentations
of the facts connected, with both Engines have not induced him to withdraw
his attention from the new Invention; and the circumstance of his not having
printed a description of either Engine has arisen entirely from his
determination never to employ his mind upon the description of those
Machines so long as a single difficulty remained which might limit the
power of the Analytical Engine. The drawings, however, and the notations
have been freely shown; and the great principles on which the
Analytical Engine is founded have been explained and discussed with some
of the first philosophers of the present day. Copies of the engravings
were sent to the libraries of several public institutions, and the effect
of the publicity thus given to the subject is fully proved by its having
enabled a distinguished Italian Geometer to draw up from these sources
an excellent account of that Engine.
Throughout the whole of these labours connected with the Analytical
Engine, neither the Science, nor the Institutions, nor the Government
of his Country have ever afforded him the slightest encouragement.
When the Invention was noticed in the House of Commons, one single
voice* alone was raised in its favour.
During nearly the whole of a period of upwards of twenty years,
Mr. Babbage had maintained, in his own house, and at his own expense,
an establishment for aiding him in carrying out his views, and in making
experiments, which most materially assisted in improving the Difference
Engine. When that work was suspended he still continued his own inquiries,
and having discovered principles of far wider extent, he ultimately embodied
them in the Analytical Engine.
The establishment necessary in the former part of this period for
the actual construction of the Difference Engine, and of the extensive
drawings which is demanded, as well as the formation of those tools
which were contrived to overcome the novel difficulties of the case, and
in the latter part of the same period by the drawings and notations of the
Analytical Engine, and the experiments relating to its contruction, gave
occupation to a considerable number of workmen of the greatest skill.
During many years in which this work proceeded, the workmen were
continually changing, who carried onto the various workshops in which
they were afterwards amployed the practical knowledge acquired in the
construction of these machines.
To render the drawings of the Difference Engine intelligible, Mr.
Babbage had invented a compact and comprehensive language (the Mechanical
Notation), by which every contemporaneous or successive
movement of this Machine became known. Another addition to mechanical
science was subsequently made in establishing principles for the lettering
of drawings; one consequence of which is, that although many parts
of a machine may be projected upon any plan, it will be easily seen, by
the nature of the letter attached to each working point, to which of those
parts it really belongs.
By the means of this system, combined with the Mechanical Notations,
it is now possible to express the forms and actions of the most
complicated machine in language which is at once condensed, precise
and universal.
At length, in November 1842, Mr. Babbage received a letter from
the Chancellor of the Exchequer, stating that Sir Robert Peel and himself
had jointly and reluctantly come to the conclusion that it was the
duty of the Government, on the ground of expense, to abandon the further
construction of the Difference Engine. The same letter contained a proposal
to Mr. Babbage, on the part of Government, that he should accept
the whole of the drawings, together with the part of the Engine already
completed, as well as the materials in a state of preparation. This
proposition he declined.
The object of the Analytical Engine (the drawings and the experiments
for which have been wholly carried on at Mr. Babbage's expense,
by his own draftsmen, workmen and assistants) is to convert into numbers
all the formulae of analysis, and to work out the algebraical development
of all formulae whose laws are known.
The present state of the Analytical Engine is as follows:--
"SKETCH OF THE ANALYTICAL ENGINE INVENTED
by
* From the "Bibliotheque Universelle de Geneve", No. 82,
The chief drawback hitherto on most , . . machines is, that they require
the continual intervention of a human agent to regulate their movements,
and thence arises a source of errors . ...
But if human intervention were necessary for directing . . . partial
operations, nothing would be gained under the heads of correctness and
economy of time; the machine must therefore have the additional requisite
of executing by itself all the successive operations required for the solution
of a problem proposed to it, when once the primitive numerical data
for this same problem have been introduced. Therefore, since, from the
moment that the nature of the calculation to be executed . . . have been
indicated to it, the machine is, by its own intrinsic power, of itself to go
through all the intermediate operations which lead to the proposed result,
it must exclude all methods of trial and guess-work, and can only admit
the direct processes of calculation. 1
It is necessarily thus; for the machine is not a thinking being, but
simply an automaton which acts according to the laws imposed upon it .. ..
To understand how the machine can now go through its functions ac-
cording to the laws laid down, we will begin by giving an idea of the manner
in which it materially represents numbers. Let us conceive a pile or
vertical column consisting of an indefinite number of circular discs, all
pierced through their centers by a common axis, around -which each of
them can take an independent rotatory movement. If round the edge of
these discs are written the ten figures which constitute our numerical alphabet,
we may then, by arranging a series of these figures in the same vertical
line, express in this manner any number whatever. It is sufficient for
this purpose that the first disc represent units, the second tens, the third
hundreds, and so on. When two numbers have been thus written on two
distinct columns, we may propose to combine them arithmetically with each
other, and to obtain the result on a third column. In general, if we have
a series of columns2 consisting of discs, which columns we will designate
2 called the storehouse
as V0, V1, V2, V3,
W4, etc., we may require, for instance, to divide the
number written on the column Vi by that on the column V4, and to obtain
the result on column v,. To effect this operation, we must impart to the
machine two distinct arrangements; through the first it is prepared for
executing a division, and through the second the columns it is to operate
on are indicated to it, and also the column on which the result is to be
represented. If this division is to be followed, for example, by the addition
of two numbers taken on other columns, the two original arrangements
of the machine must be simultaneously altered. If, on the contrary, a series
of operations of the same nature is to be gone through, then the first
of the original arrangements will remain, and the second alone will be altered.
Therefore, the arrangements that may be communicated to the
various parts of the machine may be distinguished into two principal classes: . . .
that relative to the operations and that relative to the variables ...
The Analytical Engine contains two principal species of cards: . . .
Operation cards, by means of which the parts of the machine are so disposed
as to execute any determinate series of operations, such as additions, subtractions,
multiplications, and divisions . . . and cards of the Variables,
which indicate to the machine the columns on which the results are to be
represented.
The operating mechanism of the Analytical Engine . . . might act
upon other things . . . whose mutual fundamental relations could be expressed
by those of the abstract science of operations . . . and the operating
notation and mechanism of the engine. Supposing, for instance, that
the fundamental relations of pitched sounds in the science of harmony and
of musical composition were susceptible of such expression and adaptations,
the engine might compose elaborate and scientific pieces of music of any
degree of complexity or extent ....
The Analytical Engine has no pretensions whatever to originate anything.
It can do whatever -we know how to order it to perform. It can follow
analysis, but it has no power of anticipating any analytical relations
or truths. Its province is to assist us in making available what we are already
acquainted with ....
It is obvious that, in the invention of a calculating engine, these two
branches of the subject [the mechanical and the analytical] are equally
essential fields of investigation, and that on their mutual adjustment, one
to the other, must depend all successl They must be made to meet each
other, so that the weak points in the powers of either department may be
compensated by the strong points in those of the other . . ..
by
But, let the same observer, after the same lapse of time -- the same
amount of uninterrupted experience of the uniformity of the law of square
numbers, hear the maker of the engine say to him -- "The next number
which shall appear on those wheels, and which you expect to find a square
number, shall not be so. When the machine was originally ordered to make
these calculations, I impressed on it a law, which should coincide with that
of square numbers in every case, except the one which is now about to appear;
after which no future exception can ever occur, but the unvarying law
of the squares shall be pursued until the machine itself perishes from decay."
Undoubtedly the observer would ascribe a greater degree of power to the
artist who had thus willed that event which he foretells at the distance of
ages before its arrival.
If the contriver of the engine then explain to him, that, by the very
structure of it, he has power to order any number of such apparent deviations
from its law to occur at any future periods, however remote, and
that each of these may be of a different kind; and, if he also inform him,
that he gave it that structure in order to meet events, which he foresaw
must happen at those respective periods, there can be no doubt that the observer
would ascribe to the inventor far higher knowledge than if, when
those events severaliy occurred, he were to intervene, and temporarily to
alter the calculations of the machine.
If,besides this, the contriver were so far to explain the structure of the
engine that the observer could himself by some simple process, such as the
mere moving of a bolt, call into action those apparent d.eviations whenever
certain combinations were presented to his eye; if he were thus to impart a
power of predicting such excepted cases, dependent on the will, though in
other respects beyond the limits of the observer's powder and knowledge, --
such a structure would be admitted as evidence of a still more skilful contrivance . . ..
When the construction of the Analytical engine was first attempted, I
did not seek to give it the power of making calculations so far beyond the
reach of mathematical analysis as these appear to be. I had determined to
invest the invention -with a degree of generality which should include a wide
range of mathematical power; and I was well aware that the mechanical
generalisations I had organised contained within them much more than I had
leisure to study, and some things which will probably remain unproductive
to a far distant day.
FROM
BY
CHARLES BABBAGE, ESQ., M.A.,
" I now gave my mind to philosophy: the great object of my ambition was to make out a
complete system of the univerae, including and comprehending the origin, causes,
consequences, and
termination of ail things Instead of countenance, encouragement, and applause, which
I should
have received from every one who has the true dignity of an oyster at heart, I was
exposed to
calumny and misrepresentation. While engaged in my great work on the universe, some
even went
so far as to accuse me of infidelity;such is the malignity of oysters."-
"Autobiography of an
Oyster" deciphereded by the aid of photography in the shell of a philosopher of that race,recently scolloped,
TO VICTOR EMMANUEL II., KING OF ITALY.
SIRE,
by
. . . On Mr. Gravatt applying to the Commissioners for space, it was
stated that the Engine must be placed amongst philosophical instruments,
Class XIII.
The only place offered for its reception was a small hole, 4 feet 4 inches
in front by 5 feet deep. On one side was the only passage to the office of the
superintendent of the class. The opposite side was occupied by a glass case
in which I placed specimens of the separate parts of the unfinished engine
[Difference Engine No. 1]. These, although executed by English workmen
above thirty years ago, were yet, in the opinion of the most eminent engineers,
unsurpassed by any work the building of 1862 contained. The back of this
recess was closed in and dark, and only allowed a space on the wall of about
five feet by four on which to place the whole of the drawings and illustrations
of the Difference Engine. Close above the top of the machine was a flat roof,
which deprived the drawings and the work itself of much light.
The public at first flocked to it; but it was so placed that only three persons
could conveniently see it at the same time . . . and he [Mr. Gravatt]
was continually interrupted by the necessity of moving away in order to allow
access to the numerous persons whose business called them to the
superindendent's office.
I was myself frequently asked why I did not employ a person to explain
the Difference Engine . . . but my greatest difficulty was with foreigners',
no explanation I could devise . . . appeared at all to satisfy their minds . . ..
That the nation possessing the greatest military and commercial marine in
the world --.the nation which had spent so much in endeavouring to render
perfect the means of finding the longitude --which had recently caused to be
computed and published at considerable expense an entirely new set of lunar
tables should not have availed itself at any cost of mechanical means of computing
and stereotyping such tables, seemed entirely beyond their comprehension .. .
Of the Analytical Engine
. . . In order to carry out my pursuits successfully, I had purchased a
house with above a quarter of an acre of ground in a very quiet locality. My
coach-house was now converted into a forge and a foundry, whilst my stables
were transformed into a workshop. I built other extensive workshops my-
self, and had a fire-proof building for my drawings and draftsmen. Having
myself worked with a variety of tools, and having studied the art of constructing
each of them, I at length laid it down as a principle -- that, except in rare
cases, I would never do anything myself if I could afford to hire another per-
son who could do it for me ....
Such works could not be carried on without great expenditure. The
fluctuations in the demand and supply of skilled labour were considerable.
The railroad mania withdrew from other pursuits the most intellectual
and skilful draftsmen. One who had for some years been my chief assistant
was tempted by an offer so advantageous that in justice to his own
family he could scarcely have declined it. Under these circumstances
I took into consideration the plan of advancing his salary to one guinea per
day. Whilst this was in abeyance, I consulted my venerable surviving
parent. When I had fully explained the circumstances, my excellent
mother replied: "My dear son, you have advanced far in the accomplishment
of a great object, which is worthy of your ambition. You are capable
of completing it. My advice is -- pursue it, even if it should oblige
you to live on bread and cheese". . . .
This advice entirely accorded with my own feelings. I therefore
retained my chief assistant at his advanced salary.
The most important part,ofthe Analytical Engine was undoubtedly
the mechanical method of carrying the tens .... Twenty or thirty different
plans and modifications had been drawn. At last I came to the
conclusion that I had exhausted the principle of successive carriage. I
also concluded that nothing but teaching the Engine to foresee and then
to act upon that foresight could lead me to the object I desired, namely,
to make the whole of any unlimited number of carriages in one unit of
time . .. .[See plate XI, p. 201]
This new and rapid system of carrying the tens when two numbers are
added together, reduced the actual time of the addition of any number of
digits, however large, to nine units of time for the addition, and one unit
for the carriage. Thus in ten's units of time, any two numbers, however
large, might be added together. A few more units of time, perhaps five
or six, were required for making the requisite previous arraJigements . ...
The Analytical Engine consists of two parts :--
Every formula which the Analytical Engine can be required to compute
consists of certain algebraical operations to be performed upon given
letters, and of certain other modifications depending on the numerical
value assigned to those letters.
There are therefore two sets of cards, the first to direct the nature
of the operations to be performed--these are called operation cards: the
other to direct the particular variables on which those cards are required
to operate -- these latter are called variable cards ....
The Analytical Engine is therefore a machine of the most general
nature. Whatever formula it is required to develop, that law of its
development must be communicated to it by two sets of cards. When these
have been placed, the engine is special for that particular formula. The
numerical value of its constants must then be put on the columns of wheels
below them, and on setting the Engine in motion it will calculate and print
the numerical results of that formula.
Every set of cards made for any formula will at any future time recalculate
that formula with whatever constants may be required. Thus
the Analytical Engine will possess a library of its own ....
Besides the sets of cards which direct the nature of the operations to
be performed . . . there is another class of cards called number cards . . ,
Any number which the Analytical Engine is capable of using or producing
can, if required, be expressed by a card with certain holes in it . . ..
The Analytical Engine will contain,
The Analytical Engine I propose will have the power of expressing
every number it uses to fifty places of figures. It will multiply any
two such numbers together, and then, if required, will divide the product
of one hundred figures by number of fifty places of figures.
Supposing the velocity of the moving parts of the Engine to be not
greater than forty feet per minute, I have no doubt that
I have already stated that in the Analytical Engine I had devised
mechanical means equivalent to memory, also that I had provided other
means equivalent to foresight, and that the Engine itself could act on this
foresight.
In consequence of this the whole question of making an automaton play
any game depended upon the possibility of the machine being able to represent
all the myriads of combinations relating to it. Allowing one hundred
moves on each side for the longest game at chess, I found that the combination
involved in the Analytical Engine enormously surpassed any required,
even by the game of chess.
As soon as I arrived at this conclusion I commenced an examination
of a game called "tit-tat-to, " . . . . I ascertained what number of combinations
were required for all the possible variety of moves and situations.
I found this to be comparatively insignificant. I therefore easily sketched
out mechanisms by which such an automaton might be guided . . . A difficulty,
however, arose of a novel kind .... When the automaton had to
move, it might occur that there were two different moves, equally conducive
to his winning the game. In this case no reason existed within the
machine to direct his choice: unless, also, some provision were made,
the machine would attempt two contradictory motions.
The first remedy I devised for this defect was to make the machine keep
a record of the number of games it had won from the commencement of its
existence. Whenever two moves, which we may call A and B, were equally
conducive to winning the game, the automaton was made to consult the
record of the number of games he had won. If that number happened to be
even, he was directed to take course A; if it were odd, he was to take
course B.
Deciphering
Deciphering is, in my opinion, one of the most fascinating of arts . ...
I practised it in its simplest form when I was at school. The bigger boys
made ciphers, but if I got hold of a few words, I usually found out the key.
The consequence of this ingenuity was occassionally painful: the owners
of the detected ciphers sometimes thrashed me, though the fault really lay
in their own stupidity ....
One of the most singular characteristics of the art of deciphering
is the strong conviction possessed by every person, even moderately acquainted
with it, that he is able to construct a cipher which nobody else can
decipher ....
In a conversation on that subject with the late Mr. Davies Gilbert, of
the Royal Society, each maintained that he possessed a cipher which was
absolutely inscrutable. In comparison, it appeared that we had both imagined
the same law . ...
This cipher was arranged upon the following principles -- Two concentric
circles of cardboard were formed, each divided into twenty-six or more
divisions.
On the outer were written in regular order the letters of the alphabet.
On the inner circle -were written the same twenty-six letters, but in any
irregular manner.
In order to use this cipher, look for the first letter of the -word to
be ciphered on the outside circle. Opposite to it, on the inner circle,
will be another letter, which is to be written as the cipher for the former.
Now turn the inner circle until the cipher just written is opposite
the letter on the outer circle. Proceed in the same manner for the
next, and so on for all succeeding letters.
Theatrical Experience
I was never particularly devoted to theatrical representations ....
I did, however, occasionally, in one or two rare instances, assist in a
tableau .. ..
On one occasion having joined a party of friends in their box at the
opera 'Don Juan', I escaped, by half a second, a marvellous adventure.
Somewhat fatigued with the opera, I went behind scenes to look at the
mechanism. One of the scene-shifters . . . offered to take me all over
the theatre .. ..
After a long rambling and descending endless steps, I found myself
in a vast dark and apparently boundless area .... Suddenly a little bell
rang -- the signal for my scene-shifting friend to take his post ....
Instantly my friend became invisible in the surrounding gloom.
My first step when thus suddenly abandoned, was to mount on a
large oblong platform about six feet above the floor .... Sud.denly a
flash of lightening occurred. On looking up, high above my head, I saw
an opening as large as the platform on which I stood. All there was
brightness. Whilst I was admiring this new light, and seeking my way to
the upper and outer world, two devils with long forked tails jumped upon
the platform ....
During this colloquy, the table, the philosopher, and the devils,
were all slowly moving upward to the open trap-door of the stage above.
Seeing a beam some six feet higher . . . I inquired whether it was fixed
and would bear my weight . ...
We had now reached the level of the desired beam, though not near
enough for a jump. However, still ascending, we passed it: then stooping
my head and bending my body to avoid the floor of the stage . . . I sprang
down on the beam .... My two Missionary companions continued their
course to the world above in order to convey the wicked Juan to the realms
below . . . . I soon rejoined my companions who congratulated me on
what they represented as my 'undeserved escape:' kindly hoping that I
might be equally fortunate upon some further occasion.
Mastership of the Mint
In 1846 the Mastership of the Mint became vacant. In former days
it was held by Newton. I had pointed it out in "The Decline of Science"
as one of those offices to which men of science might reasonably aspire.
A complete acquaintance with the most advanced state of mechanical
science, which the demands of my own machinery had compelled me to
improve, added to a knowledge of the internal economy of manufactories,
appeared to me to constitute fair claims to that office.
In the event of my succeeding, I had proposed to let the whole of
my salary accumulate, so that at the end of ten or twelve years I might
retire from the office, and be enabled, with the 20,000 [British Pounds] thus earned, to
construct the Analytical Engine ....
The appointment remained for a short time in abeyance; but it was
found necessary to detach Sheil from O'Connell, and the appointment was
therefore given to Shell .. ..
In 1849, on the promotion of Sheil, the Mastership of the Mint again
became vacant. I thought my own claims sufficiently known to the public;
but I had no political interest. My friend Sir John Herschel was more
fortunate, and he received the appointment.
After a few years, the office again became vacant by the resignation
of Sir John Herschel. The Government had now for the third time an
opportunity of partially repairing its former neglect. I had, however,
no political party to support me, and the present Master of the Mint, Mr.
Graham, then received the appointment.
Motives for Being on a Committee
. . . At all elections some few men . . . do all the difficult and
real work of the committee. The committee itself is, for several
reasons, generally very numerous.
Street Nuisances
During the last ten years, the amount of street music has so greatly
increased that it has now", become a positive nuisance to a very considerable
portion of the inhabitants of London. It robs the industrious of time; it
annoys the musical man by its intolerable badness; it irritates the invalid;
deprives the patient, who at great inconvenience has visited London for
the best medical advice, of that repose which, under such circumstances,
is essential for his recovery, and it destroys the time and energy of all
the intellectual classes of society by its continual interruptions of their
pursuits.
Instruments of torture permitted by the Government to be in daily
and nightly use in the streets of London:
Encouragers of street music
Conclusion
. . . [The reader] may reasonably ask what peculiarities of mind enabled
me to accomplish what even the most instructed in their own sciences deemed
impossible.
I have always carefully watched the "-exerciscl of my own faculties, and
I have also endeavored to collect from the light reflected by other minds
some explanation of the question.
I think one of the most important guiding principles has been this:--
that every moment of my waking hours has always been occupied by some
train of inquiry. In far the largest number of instances the subject might
be simple or even trivial, but still work of inquiry, of some kind or other,
was always going on.
The difficulty consisted in adapting the work to the state of the body.
The necessary training was difficult. Whenever at night I found myself
sleepless, and wished to sleep, I took a subject for examination that required
little effort, and which also had little influence on worldly affairs by
its success or failure.
On the other hand, when I wanted to concentrate my whole mind upon
an important subject, I studied during'the day all the minor accessories,
and [returned to work at] two o'clock in the morning .... [Only then did
I find repose froin] the nuisances of the London street ....
I believe my early perception of the immense power of signs in aiding
the reasoning faculty contributed much to whatever success I may have had.
Probably a still more important element was the intimate conviction I possessed
that the highest object a reasonable being could pursue was to endeavor
to discover those laws of mind by which man's intellect passes
from the known to the discovery of the unknown.
This feeling was ever present to my own mind, and I endeavored
to trace its principle in the minds of all around me, as well as in the works
of my predecessors.
BABBAGE'S
THEIR HISTORY, AND CONSTRUCTION.
E. AND F. N. SPON, 126, STRAND.
1889.
Plate of Difference Engine No. 1
Big file
" STATEMENT OF THE CIRCUMSTANCES ATTENDING THE
INVENTION AND CONSTRUCTION OF MR BABBAGE'S
CALCULATING ENGINES"
* That of Mr. Hawes. Member for Lambeth
EXCERPTS FROM
BY CHARLES BABBAGE, ESQ."*
L.F. Menabrea, of Turin, Officer of the Military Engineers
October, 1842. Translated by .Lady Lovelace, Ada
Augusta, only child of Lord Byron.
1 This must not 'be understood in too unqualified a manner. The engine is
capable, under certain circumstances, of feeling about to discover which
of two or more possible contingencies has occurred, and of then shaping
its future course accordingly. -- Note by Lady Lovelace, Translator.
"TRANSLATOR'S NOTES TO M. MENABREA'S MEMOIR."
'NINTH BRIDGEWATER TREATISE' "
Charles Babbage, Esq.
Let the reader suppose himself placed before the Calculating Engine,
and let him again observe and ascertain, by lengthened induction, the nature
of the law it is computing. Let him imagine that he has seen the changes
wrought on its face during the lapse of thousands of years, and that without
one solitary exception, he has found the engine register the series of square
numbers. Suppose now, the maker of that machine to say to the observer,
"I will, by moving a certain mechanism, which, is invisible to you, cause the
engine to make one cube number instead of a square, and then to revert to
its former course of square numbers;" the observer would be inclined to
attribute to him a degree of power but little superior to that which was
necessary to form the original engine.
PASSAGES
THE LIFE OF A PHILOSOPHER,
F.R.S., P.R.S.E., F.STAT., P. STAT. S., Hon, N.R.I.A., M.C.P.S.,
COMMANDER OF THE ITALIAN ORDER OF ST. MAURICE AND ST. LAZARUS,
[smeared]
"I'm a philosopher. Confound them all
Birds, beaata, and men; bat no, not womankind." -- Don Juan.
LONGMAN, GREEN, LONGMAN, ROBERTS, & GREEN.
1864.
[The right of Translation is reserved.]
DEDICATION.
I am, Sire,
With the highest respect,
Your Majesty's faithful Servant,
CHARLES BABBAGE.
Photograph of C. Babbage
1860
[100 K bytes]
The following excerpts from Charles Babbage's
book "Passages From the Life of a Philosopher" have
been chosen to introduce the reader to Babbage the
scientist and Babbage the man, but in only a small way
can they recreate the intimate details and personal
flavor of the original. To those who may wish to pursue
the work in its entirety, a single copy is available
for examination at the Hayden Library in the Derr
rare-book collection. This copy is also on microfilm
at the Digital Computer Laboratory.
Robert R. Rathbone
Massachusetts Institute of Technology
Cambridge, Massachusetts
January, 1952
EXCERPTS FROM
"PASSAGES FROM THE LIFE OF A PHILOSOPHER"
Charles Babbage, Esq.
Circumstances Connected with the Exhibition of the Difference
Engine No. I in the International Exhibition of 1862
Method of Carrying the Tens
(Plate XI from "Babbage's Calculating Engines")
[Big file]
There are, however, methods by which any machine made for a given
number of figures may be made to compute the same formulae with double
or any multiple of its original number . . ..
Games of skill that can be played by an Automaton
Occasionally, a few simply honest men are found upon committees.
These are useful as adjuncts to give a kind of high moral character to
the cause; but the rest of the committee generally think them bores, and
when they differ upon any point from the worldly members, it is invariably
whispered that they are crotchety fellows.
I have very frequently been disturbed by such music . . . after twelve
o'clock at night. Upon one occasion, a brass band played, with but few
and short intermissions, for five hours.
Organs Bagpipes
Brass bands Accordians
Fiddlers Halfpenny whistles
Harps Tom-toms
Harpsichords Trumpets
Hurdy-gurdies Shouting out object for sale
Flageolets Religious canting
Drums Psalm - singing
Tavern-keepers Ladies of doubtful virtue.
Public-houses .
Girl-shops Occasionally titled ladies;
Beer-shops
Coffee-shops
Servants
Children
Visitors from the country