Babbage Charles

Charles Babbage

Biografia: (Teignmouth 1791 – Londra 1871) Matematico inglese che agli inizi del XIX secolo ideò e progettò un calcolatore digitale meccanico a vapore, chiamato macchina analitica, che può essere considerato un antenato dei moderni computer. La macchina analitica era controllata da un meccanismo analogo al telaio Jacquard per la tessitura. Poteva leggere due serie di schede perforate: le schede operative, che definivano la sequenza di operazioni da compiere e le schede variabili, che specificavano su quale elemento interno operare. Le schede prese a coppie definivano quindi un’istruzione, analogamente ai moderni elaboratori elettronici. Babbage aveva immaginato la struttura e la costruzione del Motore Analitico (Analytical Engine) che risolveva i problemi di velocità di calcolo, di precisione numerica, di programmazione delle formule da eseguire semplicemente dividendo la macchina in due parti che chiamò Mill (unità di calcolo) che conteneva il programma vero e proprio e store (memoria) che immagazzinava variabili e costanti e nella quale erano conservati anche tutti i risultati intermedi dei calcoli. Mill e Store sono l’esatto analogo dei nostri moderni computer elettronici, quelli che si basano sulla famosa ‘architettura di Von Neumann’ in cui abbiamo il Processore Centrale (CPU) e la Memoria. Babbage immaginò subito un dispositivo in grado di leggere e impartire delle istruzioni al suo Analytical Engine e cominciò a chiamare in maniera differenziata le schede perforate. Le Number Cards erano quelle che conservavano i dati e potevano essere usate anche come un’estensione dello Store (memoria). Le Operation Cards dicevano al Mill (processore) quale e quando eseguire un’operazione, e infine le Variable Cards specificano in quale parte della memoria un particolare dato doveva essere preso per essere processato e in quale parte immagazzinare il risultato. Dopo poco al Motore Analitico venne aggiunta l’ultima finezza. La capacità di ripetere automaticamente una sequenza di operazioni un prefissato numero di volte. Per ottenere questo Babbage introdusse un quarto insieme di schede che chiamò Combinatorial Cards La macchina era quindi in grado di utilizzare i risultati di un calcolo, impressi nelle schede perforate, come dati iniziali per un calcolo successivo, come pure di eseguire calcoli ciclici ripetitivi. Essa era inoltre in grado di eseguire le istruzioni di un programma in un ordine diverso da quello in cui erano state introdotte, secondo procedure chiamate cicli e salti condizionati. Per molto tempo le schede perforate hanno rappresentato il supporto più comune e diffuso per la memorizzazione delle informazioni.

Opere: 1813 "Memoirs of the Analytical Society"; 1 Prefazione, in collaborazione con John Herschel, i-xxii; 2 on Continued Products, 1-31, Cambridge.

1815 "An Essay Towards the Calculus of Functions", Phil. Trans. 105, 389 423.

1816 "An Essay Towards the Calculus of Functions", Part II, Phil. Trans. 106, 179-256.

"Demonstrations of Some of Dr. Matthew Stewart's General Theorems; To Which is Added, An Account of Some New Properties of the Circle", Journal of Science, 1, 6-24.

S. F. LaCroix, "An Elementary Treatise on the Differential and Integral Calculus", Tr. Charles Babbage, John Herschel, e George Peacock, Cambridge, J. Deighton.

1817 "Observations on the Analogy Which Subsists Between the Calculus of Functions and the Other Branches of Analysis", Phil. Trans. 107, 197-216.

"Solutions of Some Problems by Means of the Calculus of Functions", Journal of Science, 2, 371-79.

"An Account of Euler's Method of Solving a Problem Relative to the Move of the Knight at the Game of Chess", Journal of Science, 3, 72-7.

"Note Respecting Elimination", Journal of Science, 3, 355-7.

1819 "On Some New Methods of Investigating the Sums of Several Classes of Infinite Series", Phil. Trans. X, 09, 249-82.

"Demonstration of a Theorem Relating to Prime Numbers", Edin. Phil. Jrl .1,46-9

1820 "Examples of the Solutions of Functional Equations" in collaborazione con Cambridge, J. Deighton.

1821 "An Examination of Some Questions Connected with Games of Chance",

1822 "Observations on the Notation Employed in the Calculus of Functions", Tr. Camb. Phil. Soc. 1, 63-76.

"Barometrical Observations Made at the Fall of the Staubbach", in collaborazione con John Herschel, Edin. Phil. Jrl. 6, 224-7.

"A Note Respecting the Application of Machinery to the Calculation of Astronomical Tables", Mem. Astron. Soc. 1, 309.

"A Letter to Sir Humphry Davy, Bart. PRS, on the Application of Machinery to the Purpose of Calculating and Printing Mathematical Tables"

"Observations on the Application of Machinery to the Computation of Mathematical Tables", Mem. Astron. Soc. 1, 311-14.

1823 "On the Theoretical Principles of the Machinery for Calculating Tables", Edin. Phtl. Jrl. 8, 122-8.

"On the Application of Analysis to the Discovery of Local Theorems and Porisms", Tr. Roy. Son. Edin. 9, 337-52.

"Scriptores Optici; or, A Collection of Tracts Relating to Optics", pubblicato in collaborazione con Francis Maseres; Prefazione di Babbage. Baldwin, Craddock & Joy, London.

1824 "Observations on the Measurement of Heights by the Barometer", Edin. Jrl. Sci. 85-7.

`Rates of the Protector Life Assurance Company', privately printed, London.

1825 `Account of the Repetition of Mr. Arago's Experiments on the Magnetism Manifested by Various Substances During the Act of Rotation', in collaboration with John Herschel, Phil. Trans. 115, 467-96.

1826 `On a New Zenith Micrometer', Mem. Astron. Soc. 2, 101-3.

A Comparative View of the Various Institutions for the Assurance of Lives, J. Mawman, London.

`On a Method of Expressing by Signs the Action of Machinery', Phil. Trans. 116, 250-65.

`On Electrical and Magnetic Rotations', Phil. Trans. 116, 494-528.

`On the Determination of the General Term of a New Class of Infinite Series', Trans. Camb. Phil. Soc. 2, 217-25.

`Diving Bell', Encyclopaedia Metropolitana, 18, 157 -67.

1827 `On the Influence of Signs in Mathematical Reasoning', Trans. Camb. Phil. Soc. 2, 325-77-

`Notice respecting some Errors Common to many Tables of Logarithms', Mem. Astron. Soc. 3, 65-7.

`Evidence on Savings Banks, before a Committee of the House of Commons', Reports from the Committees of the House of Commons, III, 1826-7, 869-558.

Table of Logarithms of the Natural Numbers from 1 to 108000, J. Mawman, London.

1829 `Account of the Great Congress of Philosophers at Berlin on the 18th September 1828', Edin. Jrl. Sci. 10, 225-34.

`A Letter to the Right Hon. T. P. Courtenay, on the Proportionate Number of Births of the Two Sexes under Different Circumstances', Edin. Jrl. Sci. NS, 1, 85-104.

`On the General Principles which Regulate the Application of Machinery to Manufacture and the Mechanical Arts', Encyclopaedia Metropolitana, 8, 1-84.

1830 `Notation', Edinburgh Encyclopaedia, 15, 394-9.

`Porisms', op. cit.,17, 106-14.

Reflections on the Decline of Science in England, and some of its Causes, (dedicated to `a nobleman', probably Lord Ashley, later Earl of Shaftesbury) B. Fellowes, London.

Sketch of the Philosophical Characters of Dr. Wollaston and Sir Humphry Davy, B. Fellowes, London.

`Mathematical Questions,' Mathematical Repository, New Series, 5, 51, 63-4, 66-7, 71-2, 178-80.

1831 `Sur l'emploi plus ou moins frequent des memes lettres dans les differentes langues', (in a letter to L. A. J. Quetelet), Corr. mathematique et physique, 7, 135-7

Specimen of Logarithm Tables (21 vols.): two pages from Babbage's edition of the logarithmic tables printed in many different coloured inks on many different colours and shades of paper - a single copy was printed (now in the Crawford Library), B. Fellowes, London.

Table of Logarithms of the Natural Numbers from 1-108,000, on Different Coloured Papers, single copy printed (28 volumes are now in the Crawford Library. Babbage said 35 were originally printed), B. Fellowes, London.

1832 `On the Advantage of a collection of Numbers, to be Entitled the Constants of Nature and Art', Edin. Jrl. Sci. NS6, 334-40. (Expanded versions of this paper were later published in: Compte Rends des Travaux du Congres General de Statistique, 1835, 222-30, Bruxelles; and The Annual Report of the Board of Regents of the Smithsonian Institution, 1856, 289-302).

On the Economy of Machinery and Manufactures, Charles Knight, London. A second and third edition were published in 1832, and a fourth edition with index in 1835; translated into French, German, Italian, Spanish, Russian, and Swedish. (In 1833 three chapters were published as a pamphlet, On Currency, on a Near System of Manufacturing, and on the Effect of Machinery on Human Labour, Charles Knight, London; a further extract was published in 1899 as How to Invent Machinery, ed. William H. Atherton, Manchester.)

1833 A Word to the Wise, John Murray, London. (reprinted in 1856 and subtitled: Observations on Peerage for Life.)

1834 Abstract of a Paper Entitled: `Observations on the Temple of Serapis at Pozzuoli; with Remarks on Certain Causes which May Produce Geological Cycles of Great Extent' (full paper published in 1847), Richard Taylor, London.

1835 `Une lettre a M. Quetelet de M. Ch. Babbage relativement a la machine a calculer', . Acad. Roy. Bruxelles, Bulletins, 2, 123-6.

`Letter from Mr. A. Sharp to Mr. J. Crosthwait, Hoxton, Feb. 2, 1721-2, Decyphered by C. Babbage, Esq. From the Original Letter in Shorthand'; in An Account of the Revd John Flamsteed, the First Astronomer-Royal, 348, by Francis Baily, Admiralty, London.

1837 The Ninth Bridgewater Treatise; A Fragment, John Murray, London. 2nd. ed. 1838.

`On the Mathematical Powers of the Calculating Engine' (Ms. in Museum of History of Science, Oxford); published 1973, Brian Randell (ed), The Origins of Digital Computers, 17-52, Springer.

1838 `On Impressions in Sandstone Resembling Those of Horses' Hoofs', Proc. Geol Soc. 2, 439.

1839 `Letter from Mr. Babbage to the Members of the British Association for the Promotion of Science', Richard Clay, London.

1842-3 `Notions sur la Machine Analytique de M. Charles Babbage' (by L. F. Menabrea), Bibliotheque Universelle de Geneve, 41, 352-76; tr. with additional notes by Ada Lovelace as `Sketch of the Analytical Engine', (1843) Scientific Memoirs, iii, 666-731. (On page 373 of the Menabrea paper le cas n = [infinity], was misprinted as le cos n = [infinity]. Ada translated this as `when the cos of n = [infinity]`, which is nonsense.).

1843 `Statement of the Circumstances Respecting Mr. Babbage's Calculating Engines' (by Sir Harris Nicolas), privately printed, London.

`Statement of the Circumstances attending the Invention and Construction of Mr. Babbage's Calculating Engines', Phil. Mag. 23, 234-5.

`Addition to the Memoir of M. Menabrea on the Analytical Engine', Ibid, 235-9.

`Description of the Boracic Acid Works of Tuscany'; Handbook for Travellers in Central Italy, 178-9, John Murray, London.

1847 `On the Principles of Tools for Turning and Planing Metals'; in Turning and Mechanical Manipulation, by Charles Holtzapffel, 2, 984-7, Holtzapffel, London.

`Observations on the Temple of Serapis at Pozzuoli, Near Naples', Taylor, London.

`The Planet Neptune and the Royal Astronomical Society's Medal', The Times, 15 March.

1848 Thoughts on the Principles of Taxation with Reference to a Property Tax, and its Exceptions, John Murray, London. 2nd ed.1851; 3rd ed. 1852.

1851 `Laws of Mechanical Notation', privately printed, London.

The Exposition of 1851; or Views of the Industry, the Science, and the Government o/England, John Murray, London.2nd ed. 1851.

`Notes Respecting lighthouses', privately printed, London.

1852 `Note Respecting the Pink Projections from the Sun's Disc Observed during the Total Solar Eclipse in 1851', Monthly Notices Astron. Soc. 12, 209-10.

1853 `On the Statistics of Lighthouses', Compte Rends des travaux du Congres Generals de Slatistique, 230-7, Bruxelles.

1854 `Report on the Opthalmoscope', (by T. Wharton Jones), British and Foreign Medical Rev. 14, 425-32.

`Mr. Thwaites's Cypher', Jrl. Soc. Arts, 90, 663-4, 93, 707-8, 95, 732-3, 98, 776-7.

1855 `Submarine Navigation', Illustrated London News, 749, 623-4.

`On the Possible Use of the Occulting Telegraph at Sebastapol', The Times, 16 July, 6 f

`A Method of Laying the Guns of a Battery Without Exposing the Men to the Shot of the Enemy', Illustrated London News, no.757, 210.

`Sur la machine suedoise de MM. Scheutz pour calculer les tables mathematiques', Comptes rendus hebdomadaires, 41, 557-60, Academie des Sciences, Paris.

`Cypher Writing', Jrl. Soc. Arts, 159, 40-1.

1856 `Scheutz's Difference Engine and Babbage's Mechanical Notation' (by Henry Babbage), Proc. Inst. Civil Eng. 15, 497-514. Also published as separate pamphlet.

`On the Action of Ocean Currents in the Formation of the Strata of the Earth', Quart. Jrl. Geol. Soc. 12, 366-8.

`Analysis of the Statistics of the Clearing House During the Year 1839', Jrl. Stat. Soc. 19, 28-48. Also published as a separate pamphlet.

Observations Addressed at the Last anniversary to the President and Fellows o/'the Royal Society, John Murray, London.

1857 `Table of the Relative Frequency of Occurrence of the Causes of Breaking of Plate Glass Windows', Mechanics Mag. 66, 82.

1860 `Observations on the Discovery in Various Localities of the Remains of Human Art Mixed with the Bones of Extinct Races of Animals', Proc. Roy. Soc. 10, 59-72.

`On Easily Recognisable Signs in Drawings', Proc. Fourth International Statistical Congress, 380, London.

`Letter to Dr. Farr, on the Origin of the International Statistical Congresses', Proc. Fourth International Statistical Congress, 505-7, London.

1864 Passages on the Life of a Philosopher, Longman, Green, London. (`A Chapter on Street Nuisances' was published by John Murray prior to publication of the book.)

1865 Thoughts upon an Extension of the Franchise, Longman, Green, London.

1868 `Observations on the Parallel Roads of Glen Roy', Quart. Jrl. Geol. Soc. 24, 273-7.

(1889) `History of the Analytical Engine' (incomplete), published posthumously with additions by Henry Prevost Babbage as Babbage's Calculating Engines, Spon, London.

Bibliografia:

Webliografia: http://www.teknemedia.net/magazine/dettail.html?mId=580