Le Sottisier du bac (French Edition)

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Saint flour l exil terrestre. Le Sottisier des Journalistes Le sottisier du bac. Provide feedback about this page. There's a problem loading this menu right now. Get fast, free shipping with Amazon Prime. Get to Know Us. English Choose a language for shopping. Amazon Music Stream millions of songs. Amazon Drive Cloud storage from Amazon. Alexa Actionable Analytics for the Web. Therefore, students are very unlikely to get a 20 out of 20 or more it is actually possible to get more than 20 because of options. It is also very rare to see scores lower than 5.

Grade inflation has become a concern. Between and , the proportion of students who received an honour in the general baccalaureate doubled. European section is an option in French high schools to teach a subject through a European language other than French. It also gives pupils the opportunity of having more hours in the language studied.

It is also an opportunity to learn more about the culture of the country of which the language is being spoken. For example, learning History in Spanish the history of Spain and that of Central and South America would be emphasized. Teachers present their lessons in English , German , Italian or Spanish.

At the end, students can receive a "European section" mention on their baccalaureat. Students may not redo the entire examination in September; the September examinations may be taken only by those who have not been able to take the June examinations for serious reasons such as illness. It can, of course, be taken only after completion of the necessary coursework, which is entirely in French. From Wikipedia, the free encyclopedia.

For other uses, see Baccalaureate disambiguation. This article needs additional citations for verification. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed. September Learn how and when to remove this template message.

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CS1 French-language sources fr Articles needing additional references from September All articles needing additional references All articles with unsourced statements Articles with unsourced statements from January Views Read Edit View history. In other projects Wikimedia Commons. They were replaced by seven priests all born in the town. In the college was closed, but it was reopened under the name of the Ecole Centrale.

It was there that Ampere was a professor from to In the Ecole Centrale was replaced by a municipal secondary school Fig. The distance from Lyons to Bourg at the beginning of the nineteenth century was too great to permit Ampere to return each day to his home. Circumstances obliged him to live in lodgings in Bourg, while his wife remained in Lyons; for on August 12, , their son Jean-Jacques was born. His aspirations may be gathered from a single paragraph of a letter he wrote at this time to his wife: The Lycee Lalande at Bourg-en-Bresse.

Those luminous thoughts, however, must be sought amidst the record of grim facts: Cela passait toute expression. Julie Ampere au citoyen Ampere. Consolation, tinged with the mildest of admonishment, came with little delay from Lyons: Tu fais done toujours ces vilaines drogues. This correspondence, which has been described as a veritable conjugation of the verb aimer , ends abruptly, for calamity once more overtook the great philosopher, and plunged him into despair. His Julie died on July 13, The drama is intensified by the struggle that Ampere had made to obtain an appointment in Lyons whereby he hoped to secure means to alleviate the sufferings of his wife, and by the coincidence that Bonaparte, as first Consul of the Republic, had just nominated him, on the advice of Lalande and Delambre, as a professor at the Lycee of that city.

The world was left to him desolate, and he naturally sought to withdraw from the scenes that once delighted and now tortured him. Four years later he became Inspecteur General of the University of Paris. From to he was a member of the Bureau Consultatif des Arts et Metiers, and in a member of the Institute. He entered the Academie des Sciences in the section of Geometry. During this period his activities were as intense, thorough, and illuminating as they were multifarious. He was always a man of science, and in everything a man of fervour.

Intermittently he was a man of faith. Following upon the work of Pascal, Fermat, and Buff on, it dealt with the mathematical theory of play, and with the evaluation, in accordance with the laws of probability, of the danger that awaits a player who takes a prescribed chance. Three years later he extended this investigation and published an account of his researches on the application of the Calculus of Variations to problems in mechanics. From that time until he contributed other papers on purely mathematical subjects; he proceeded into molecular physics and chemistry, and added a memoir upon the determination of the proportions in which bodies combine, taking account of the number and disposition respectively of the molecules of which the integral parts are composed.

Then followed his brilliant series of memoirs on electro-dynamics, for which most of his previous studies was unconsciously a preparation. His immortal work on the mutual action of tw r o currents was published in Annates de Chimie et de Physique , vol. It is rarely that a phenomenon in physics appears suddenly in the firmament of knowledge. Information concerning the discovery reached Paris, by way of Switzerland, on September 11, His contributions to the subject were read at its seances on September 18 and 25, and October 9 and 30 of that year.

He introduced the astatic needle, and he showed that the directive force of a current is always exactly perpendicular to the direction of the current. Such currents, he suggested, might be caused by chemical action between the heterogeneous materials in contact within the globe, in accordance with the principle established by Volta for metals. He declared that whatever hypothesis might ultimately be adopted there would remain these three new facts: He emphasized the fact that in this electro- dynamic action consideration has to be given rather to plane areas than to straight lines.

He also drew attention to the effect of increasing the number of turns, and to the comparatively small importance of shape of area. Moreover he introduced the idea that elementary portions of circuits could be dealt with, as regards their electric currents, in accordance with the principle of the parallelogram of velocities, i. Parallel Elements of Circuits.

The impossibility of subjecting infinitely small portions to experiment had been overcome by him by precise observations upon portions of finite length placed successively with respect to one another at different distances and in different positions— i. Oersted, Arago, Ampere, H. He discovered the mechanical action between electric currents, and he established mathematically and by physical demonstration the law of that action.

Then follow his experimental laws of steady currents so far as the mechanical force upon other conductors is concerned. He found that two equal currents close together Fig. He showed that every linear conductor carrying a current is equivalent to a magnetic shell, the bounding edge of which coincides with the conductor, and that the moment per unit area of the shell— i.

He also proved by experiment that if there are three conductors A, B, C Fig.

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It was the first example of a set of forces in which the actions are exerted in lines at right angles to the respective directions of the forces, and not in the direction of the forces themselves. Moreover, the intensity depends not simply upon the distance r between acting particles of conductors, but upon a variable element Fig. Ultimately he identified the coefficients, and he then expressed the required force as I I x sin a. For his purpose it sufficed that directed forces acted between particles across an abyss. Nevertheless, his conception that mole cules subjected to the action of continuously circulating electric currents might be regarded as equivalent to magnets was a significant step in that advance of knowledge relating to the constitution of matter which has led the modern school to the equations of free space, and to the present electron theory.

If from this point, the highest in his scientific career, the rugged ground over which Ampere trod is contemplated, the impression upon the mind is that during those dreary years lie moved consciously towards a definite object. Inspired by a passion for research, and guided by his genius, he concentrated upon a single purpose.

Once before he had been near to success and had just missed his mark; here at last was a reward in full measure. Pourquoi ne suis- je pas reste toute ma vie professeur de chimie a Bourg ou a Lyon! Nous riions de si bon coeur a Lyon! Mais ici on ne rit pas. Gay-Lussac had just published in the Amides de Chimie the results of his experiments upon Iodine.

It was at that stage that he decided to return to mathematics, which he had somewhat neglected in favour of chemistry.

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No schoolboy ever went back to his playground with more enthusiasm: Je vais me remettre aux mathematiques. It happens that by examining the biography of his English contemporary, Sir Humphry Davy, a significant side-light can be thrown upon his association with the early history of Iodine. The fame of Ampere extended throughout Europe, and men of science were anxious to make his acquaintance.

Incidentally the account reveals the magnanimity of the Emperor Napoleon towards men of scholarly attainments. Napoleon had sternly refused his passport to several of the most illustrious noblemen of England, but he gave it to Davy unconditionally. Faraday , is not recorded. It had been in the possession of the French chemists for more than twelve months, but they had not determined its nature and composition. Courtois, a manufacturer of saltpetre in Pans.

When he reached home it had vanished. In the Nouvelle Biographie Generate , vol. In the Revue des deux Mondes for February, , there are two appreciative articles concerning him by Sainte-Beuve and by the younger Littre. Janet, on various aspects of his achievements and history. Add to these the works of De la Rive, and it will be realized that in literature the name and fame of Ampere are well guarded. His electro- dynamic theory receives extensive treatment in the works of Maxwell, and it provides Tait with a theme in quaternions. See also Forbes, Philosophical Magazine, February, His early efforts in physics, as De Launay has pointed out, were comparatively non-productive.

He perhaps realized this, for as the result of his conversations with Davy he proceeded to make a name as a chemist. Nevertheless in he confessed: The surface ripples were unable to divert the steady undercurrent of concentrated thought that led to such results as his electro-dynamic theory. Mathematics kept him to the track. It is usual to associate Ampere with the invention of the electric telegraph, but it is more appropriate to think of him in this respect as one of a large group who contributed at the initiation of the idea.

Ampere directed attention to a notion put forward by Laplace that it might be possible to cause a magnetic needle to deflect at a very great distance by using long conductors with a battery in circuit. Although plain living and high thinking had been his rule, Ampere in was on the border of bankruptcy. His sister Josephine v r ho had tried to maintain his domestic budget in equilibrium and to protect him from household cares, was at last obliged to confess to a negative balance: He had expended most of this sum upon instruments for his experiments. For about ten years he had been troubled also with rheumatism.

To complete his discomfort, critics were busy. Beyond the borders of France, criticism at one time was even more severe. He had lost all illusions about life. He knew at last the meaning of detachment. He had also learned that: Le vrai but de la politique ne doit pas etre de rendre les hommes heureux, mais de les rendre meilleurs. He had even learned to cast aside the credulity that says: When searching at the Bibliotheque for these portraits for the present story, there were found by good fortune some manuscripts Lyons Library, References , , of exceptional value, one page of which is reproduced in Fig.

It is part of the draft of his famous Memoires of and on the mutual action of two conductors. That Ampere disliked writing may be inferred: He could obtain no inspiration when seated; he preferred to stand up or to walk about when thinking. His duties as Inspector-General of the LWiversity obliged him to move about France a good deal, and it was his custom to associate his ideas with the places where they originated in his mind: His intention was to establish psychology as a science for all time.

MAH'l K A v. From an Engraving of a Drawing from Life. This explains why a letter to him from Davy upon physics and chemistry received no reply: Andre Marie Ampere died of pneumonia at Marseille on June 10, , and was there buried. In his remains were transferred to Montmartre Cemetery. Thus his works follow him.

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They constitute the proper memorial of a philosopher. Y et, if there is ever to be a temple of scientific research in Paris, devoted in the noblest sense to the welfare of mankind, France may appropriately write across its portal the name of Ampere, for his gifts to humanity can be repaid only in contributions that further the purpose for which he lived. His descent can be traced to Zanino Volta of Loveno, and to Martino Volta who in the year was a merchant of Venice, trading in wool on the Rialto. AVith a happy disposition, great powers of application, a sense of order, and his father s guidance in his studies, he soon attained an enviable place amongst his fellows at the public school of Como.

The Royal Seminary at Como put the finishing touches upon his education, and so far as can be judged, his early leanings were towards prose and verse. By the time he was twenty-four, however, chemistry and electricity cast upon him spells that caused Italy to lose a poet, and natural science to gain a pioneer.

Volta was not destined to be merely a chemist and a physicist; he became a man of affairs who directed the thoughts of Europe to noble purposes. Two years later he was called to occupy the chair of physics at Pavia. In he visited Bologna and Florence. In he proceeded to Germany, Holland, England and France, to confer with such intellectual giants as Lichten- berg.

To realize the conditions under which, at this time, he was carrying out his researches, it must be remembered that all Europe was at war, and that his home at Como was at the very vortex of the tempest that raged between Austria, France and Italy. In the Austrians dominated the passes of the Alps, and they determined upon an attack on Genoa.

The effort was successful, but it was made at the expense of their control of the approaches to Italy. With 35, men and 5, horses, he traversed the narrow pass of the great St. His entry into Italy in was greeted with rejoicings; for the educated classes sought liberty and expected it from the French, who were regarded as deliverers, and it was the policy of Bonaparte to come to terms in order to permit of concentration elsewhere.

Time, place, and circumstance conspired to establish friendly relationships between Volta and the First Consul. In , at the invitation of Bonaparte, Volta visited Paris and gave a demonstration before a large meeting of the French Institute. Scarcely had it concluded when Bonaparte proposed that Volta should receive a gold medal. He also bestowed upon him crowns for his travelling expenses. He nominated him a member of the Italian Consulate, and he raised him to the dignity of Comte and Senator of the realm of Lombardy. By perpetuating his name in the unit of electro-motive force, electricians long ago placed their laurels upon Volta.

Some of it was saved, however, and photographs exist of most of the instruments as they appeared before the calamity. In the course of a recent visit to Italy it has been possible, through the courtesy of Professor Felice Scolari and of the Director. In addition, by the kind permission of Professor Francesco Massardi, it was possible to examine at the Reale Istituto Lombardo, in the Palazzo Brera, Milan, the original manuscripts of Volta and certain reproductions scrupulously prepared of essential portions of the apparatus as it existed prior to the fire.

The age that followed him has confirmed the value of the discoveries associated with the name of Volta: These electrical investigations of Volta mark the transition from the old regime of electrostatics to the dynasty of galvanic action. At the age of eighteen he was in correspondence with the French philosopher, Jean Antoine Nollet , who had distinguished himself in by sending a shock from a Leyden jar through of the Royal Guards. According to Arago the first electrometer is due to Darcy and Le Roy.

Nollet suggested the more sensitive form in which two wires open like the legs of a compass; Cavallo added a small sphere at the end of each of the two wires, and Volta obtained increased sensitiveness by substituting a pair of dry straws. In or Volta introduced his hydrogen-lamp Fig.

He was probably the first to ignite inflammable gases in closed vessels. It led to further experiments upon the ignition of inflammable gases by electric sparks, and it entered into his scheme for electrical communication. His proposal is indicated in Fig. An iron transmission wire A B was to be supported on insulating posts a, b, c, d. It is right to add that the principle of such a method of electrical communication was known long before In the Philosophical Transactions of the Royal Society for , volume 43, William Watson gives an account of a method of bring bodies electrically, and he refers to the ignition of gas by electric sparks.

Moreover, in those Transactions for , volume 45, Fig. They also succeeded in signalling in this manner across the Thames at Westminster Bridge. The evolution of the electrophorus is somewhat difficult to trace. In England, John Canton —72 established the principle of electrostatic induction. At about the time he had perfected the electrophorus, it may be assumed that he was perplexed by the question of the Fig. In the spring of he journeyed to England. He examined the manufacturing centres, the canals, and the harbours.

At Portsmouth he visited the Fleet, under Admiral Howe, of twenty ships of the line, and went on board H. Regina of ninety-eight guns; and at Greenwich he went over the Royal Observatory. During this stay in England he became acquainted with Dr. Applied for Receiving a Signal. It appears, therefore, that he recognized it as primarily an apparatus for facilitating the measurement of electric charges, rather than as a generator of static charges.

The illustrations in Figs. He advocated the use of a very thin e. It gave him world-wide fame. Attention was directed to its importance by Dr. The condenser 2 is said to have been charged by the evaporation of liquids. These are from the Istituto Lombardo. Volta Apparatus Preserved at the University of Pavia, including a Condensing Electroscope 1 , a Pila of square form, and a Terpedine preserved in alcohol. Cavendish used 49 Leyden jars of extremely thin glass, disposed in seven rows. He compared their capacity quantitatively with that of a plate condenser of crown-glass dielectric of known dimensions.

He calibrated the electrometer by dividing the charge of one jar between two similar jars. He then charged a row of Leyden jars, and observed how many times it was necessary to charge the plate condenser from the row of jars in order to reduce the potential of the row to one-half the initial value. Como, where Volta was born and worked and died.

It bears upon a plaque the words: The fact that the theory of the condenser was known before Volta, however, in no way detracts from the value of his work on the condensing electroscope. To close the account of this middle period of his career, it is appropriate to recall the words of his contemporary Thomas Thomson, the historian of the Royal Society who wrote: We are more indebted to Mr.

In this Paper Phil. By means of it Lavoisier, Laplace, and himself succeeded in ascertaining the existence of negative electricity in the vapour of water, the smoke of burning coals, the air produced by the solution of weak sulphuric acid. The years following were not spent wholly in Italy. Then happened the stimulating event that, like a microscopical crystal falling into a super-saturated solution, converted the limpid facts and opinions of his mind into a brilliant notion. On August 30, , Luigi Galvani of Bologna observed by chance the convulsions of a dead frog that was in contact with metal.

Galvani s memoir entitled De viribus electricitatis in niotu musculari commentarius appeared in , at a time when V olta was engaged upon his investigations upon inflammable marsh gas. On April 3, , he wrote to Galvani concerning the frog movements, and a few weeks later he spoke in praise of the discovery. The experiments of Professor Galvani, until commented upon by Professor Volta, had too much astonished, and perhaps, in some degree perplexed many of the learned in various parts of Europe. To Professor Volta was reserved the merit of bringing his countryman's experiments to the test of sound reasoning and accurate investigation; he has explained them to Dr.

Bennet of Worksworth; and he has detected in the metals, which Dr. Galvani considered as mere agents in conducting his animal electricity, that very existing principle which the Doctor and his followers had overlooked. It is necessary first to introduce Tiberius Cavallo, an Italian physicist resident in England, who in published in London a treatise on atmospheric electricity.

He was responsible for improvements in the electrometer and was elected to the Royal Society. The second part, which is a direct continuation of the first, is dated October 25, This letter was communicated to the Royal Society, and it was published in the Transactions of , volume 83, p. Again it was the instrumental value of the discovery that appealed to him—for here was an electrometre animal.

He tried the effect of a two- metal probe upon detached portions of animals, and upon fragments, without any special preparation of the nerves. His field of inquiry possessed no boundaries. Then he succeeded, and he was thus able to associate the action with the nerves of flexor muscles. In this communication , Volta is careful to state that Galvani was the first to show that the electric stimulus of the nerves results in excitation of the muscles, although the electric current itself may not reach the muscles. He also describes an experiment in which he placed the bowl of a silver spoon on one side of his tongue and tinfoil on the other.

Upon reflection he was reminded that the nerves of the tongue relate to taste and not to movement. The motor nerves are further back. The earlier history of the effects of electricity upon animals probably extends to remote observations. Wenn man zwey Stricken Metall, ein bleyernes und ein sil- bernes, so mit einander vereiniget, dasz ihre Pander eine Flache ausmachen, und man bringt sie an die Zunge, so wird man einen gewissen Geschmack daran merken, der dem Geschmack des Eisenvitriols ziemlich nahe kommt, da doch jedes Stuck besonders nicht die geringste Spur von diesem Geschmacke hat.

Nun ist es nicht wahrscheinlich, dasz bey dieser Yereinigung der beiden Metalle, von dem einen oder dem andern eine Auflosung vorgehe, und die aufgeloseten Theilchen in die Zunge eindringen. Man musz also schlieszen, dasz die vereinigung dieser Metalle in einen von bey den oder in alien beyden eine zitternde Bewegung in ihren Theilchen verursache, und dasz diese zitternde Bewegung, welche nothwendig die Nerven der Zunge rege machen musz, oberwalmten Geschmack hervor bringe.

From this accusation he defended himself in a written statement denying that he had favoured the transfer. Earlier in that year the municipality of Como had sent him in company with the Conte G. At the end of the year he applied, unsuccessfully, to be allowed to retire from the University of Pavia. The quotation from his letter to Cavallo, however, leaves no doubt that he had a vision of such a current in , and that the production of a continuous flow became his objective.

In making known to the scientific world the successful issue of these later investigations, he resorted to England as a medium of communication. It was read on June 26, In the History of the Royal Society it is explained that owing to the state of hostilities that then existed between England and France, one portion of the paper arrived in London several months before an opportunity occurred for sending the remainder. Briefly, Volta explained that he had been experimenting on the electricity excited by the simple mutual contact of metals of different kinds, and other different conductors, including liquids.

The result was the construction of an apparatus—the pile—which in its effects resembled those from Leyden jars, but capable of giving a continuous discharge. Then he described the construction: Some of these are illustrated in Figs. With these he tried various arrangements of connection, rows and columns, and he investigated the effect of reversals of polarity.

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Then, if the apparatus is sufficiently large and in good order, a sensation of light will be experienced in the eyes, the lips will be convulsed, and the end of the tongue will feel a painful pricking sensation followed by the sensation of taste. The adaptation of his own body as a testing equipment, however, did not end there. He described experiments in which the sensation of hearing noise is excited by sending a current through the ears from 30 or 40 couples. Lastly, he experimented with Ins nose, with the result that more pain was produced, but no sense of odour.

The discussion, which began in his day, regarding the seat of the electromotive-force, extends into the present century, and it is as far as ever from settlement. There is also shown the Pila Secondaria of Ritter. All from the Istituto Lombardo. In his reply to criticism he remarked that he had never attributed to the metals exclusively the power of causing the electric effect by their mutual contact. He had proved by many experiments that this power belongs to all conductors, that it is in general more marked between metals, but that it also manifests itself in the case of metals and moist non- metallic conductors.

He confessed that in his earlier experiments upon contact, he had used a prepared frog Fig. Similar effects had been obtained with static electricity. By arguments such as these, free from rancour, based upon direct evidence and couched in moderate language, he held his own and convinced Europe. The mystery of cause and location remained, but as to effects he left nothing in doubt. These investigations were in the years While sifting, the gold-leaves diverge, without help from the condensing plates, and are found to be positively electrified.

At the end of the eighteenth century and at the beginning of the nineteenth, the Volta pile in innumerable forms became the vogue, and experiments on nerve and muscle a fashionable amusement. Thus, for example, John Cuthbertson, writing in , describes a demonstration in which the apparatus was arranged to produce contractions in the head of an ox, after separation from the body.

Similarly for a dog, he explains that: Frightful convulsions may be produced. The mouth will open, the teeth wall gnash, the eyes roll in their orbits, appearing as if the animal w T as restored to life, and in a state of agony. In the laboratories of Europe, nevertheless, the investigation by direct experiment of contact theory had almost continuously engaged attention. In this tribute to the great Italian philosopher, it must be recorded that although the mystery of contact-electricity, with which he endowed us, remains unsolved, it is still a potent incentive to research.

Maxwell, Heaviside, and Kelvin w ere not all in complete accord concerning the action. The questions they w r ere concerned w r ith were: When the two metals are in contact, is the air outside the zmc at a different potential from that of the air outside the copper? Is the seat of the electromotive-force at the air-surface, and if so what part is played by the junction, remembering that a force cannot exist where it is not?

Is electromotive-force a force in the Newtonian sense? What is the part, if any, played by moisture? Lift them together into contact with N. Break contact with N. No divergence of G. Slight divergence of G. In other words, lift D up and down between N and C. Great divergence of G. Bring a stick of rubbed sealing-wax near B. Divergence of G increases. Divergence of G diminishes. Interchange D and C and replace sealing-wax by glass. The charge on G is then vitreous positive. If care is taken to keep the plates parallel, the electrification will now be greater than in the previous cases 1 — 4.

It fails if the last connection between the zinc and the copper when D is lifted is through water. Note the deflection showing resinous negative electricity. The electrometer deflection does not alter. Lower C, there is still no motion of the electrometer needle— not even when C again touches the little mound of water. Hold C parallel to D with the water unbroken.

Lord Kelvin remarks that this effect was not known to Volta—it is the recovery of the Voltaic cell from electrolytic polarization.

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The apparatus, illustrated in Fig. Kelvin concluded that the Volta force is a resultant Fig. The original marble, by Gio Battista Comolli, was entirely destroyed. Heaviside suggested that on making contact between zinc and copper the first action is to remove the air from the zinc over a patch. There the disturbance begins, i. The boundary of the patch thus forms the first line of magnetic force. The work done by the zinc-air force is then equated to the sum of the electrostatic energy in the condenser formed by the system, the Joule heat in the conducting system, and the work resulting from the obscure action, if any, at the copper-air surface.

In April, , Volta wrote to Humboldt stating that he was engaged upon electrometry, particularly with regard to the capacity of conductors of various forms and sizes, and the relationship of capacity to electric pressure or tension. He found that the tension diminished exactly as the capacity was augmented. The end of the most active part of his life was approaching. In July, , he was asked by the representative of a Russian University to transfer his home to that country. His reply gives an indication of what his home meant to him and his outlook upon life at that time: Other interests more dear to my heart, and other circumstances, oblige me to refuse.

At the age of nearly 60, with two brothers ecclesiastics more aged who live with me, a wife, and three young children, I am too much attached to this family, who cherish me, and to a country that has not been ungracious. Happy in a moderate fortune and in an annual pension of francs which the Government accord me as an emeritus Professor of the Universitv of Pavia, and as a member of the National Institute, what can I desire more for the few years that remain to me?

Voila, mon respectable Professeur, ce que je dois repondre a vous et a votre ami. So far as his manners are concerned, Arago was probably wrong, for the evidence discloses a philosopher singularly gracious, fair-minded, and companionable. His relations with the world of science then ceased. In he had a slight attack of apoplexy, and on March 5, , after a fever, at the age of 82, he died.

Sir Charles Wheatstone, F. It was originally brought together by George III. References to researches to which the relics here illustrated relate are to be found in innumerable volumes. If with these are included pamphlets of a controversial character, and articles in scientific and biographical works, the publications relating to Wheatstone become somewhat overwhelming. By judicious selection, however, the essential literature can be reduced to a few classic books and papers.

So far as the scientific aspects of his achievements are concerned, the commemoration volume published in by the Physical Society of London, entitled, The Scientific Papers of Sir Charles Wheatstone supplies all that is required for general knowledge of his discoveries and of his teaching. Charles Coles Adley, and the second by Mr. These luminous contributions to the subject are both printed in vol.

To them must be added the obituary notice, written by one of his friends, which was printed in the Proceedings of the Royal Society , vol. In language that is at once appreciative and critical, it conveys a conception of the human side of Wheatstone, and leaves with us the impression of a man of high principle, of fine intelligence, and of invincible determination in research and its applications. What was the secret of his success? But by what in- lie led along the path of research to the pinnacle Charles Wheatstone was born in February, , in Gloucestershire.

Charles, who had received a private school education, showed early promise of mechanical ingenuity, and as he had clear notions of dynamical principles, he was not long in giving evidence of his capabilities. In he attracted attention by exhibiting an instrument the name and construction of which prove him to have possessed a sense of humour well calculated to dispel any priggish qualities that might have developed in such a clever youth.

The music appeared to proceed from a combined harp, pianoforte, and dulcimer. Wheatstone himself described it as an application of a general principle for conducting sound. It is noteworthy that this instrument was exhibited in the Adelaide Gallery, afterwards the scene of his experiments on the velocity of electricity and now part of a restaurant, to the east of the church of St. There is evidence also that direction was given early to his scientific work by his comprehension of the importance of the undulatory theory of light propounded by Thomas Young This was the central thread of common sense upon which the pearls of analytical research were strung.

His collected papers indicate how firm was his grasp of the meaning of wave-motion, and his researches show with what ease he was able thereby to transfer his ideas from acoustics to optics, and from optics to electricity. The Kaleidophone was a steel rod of oblong section, fitted rigidly at its lower end into a heavy base-block, and provided at the top with a white bead.

When displaced and suddenly released, the bead traced a curved path —determined by the respective periods and phases of the two motions of the rectangular rod—similar to the outlines obtained with a modern cathode-ray oscillograph. The lowest curve is permanently fixed; the upper two curves are modified in phase respectively by the movement of the sliders. The vertical rod is held near its middle point by a ball-and- Fig.

Adjustable Form of Kaleidophone. The driving wheel causes the horizontal transverse shaft to rotate, and motion from this shaft is transferred through a friction disc to a lateral shaft. The position of the driven disc on this lateral shaft can be varied by turning a milled head at the end of that shaft, and the difference m length is taken up by a sliding clutch. Harmonic motion is thus communicated through eccentrics to the lower end of the vertical rod. It may be supposed that this apparatus was associated with his work in with reference to resonance in air columns.