Biography of Jean-Antoine Nollet

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Jean-Antoine Nollet was French clergyman, experimental physicist, and leading member of the Paris Academy of Science. He constructed one of the first electrometers and developed a theory of electrical attraction and repulsion that supposed the existence of a continuous flow of electrical matter between charged bodies.

Nollet was the first professor of experimental physics at the University of Paris. He was a great popularizer of electrical phenomena. Jean-Antoine Nollet was born at Pimpre, Oise, France, November 19, 1700. His peasant parents sent him to study at Clermont and Beauvais. He went later to Paris to prepare for the priesthood. In 1728 he received the deaconship and applied immediately for permission to preach.

Although Jean-Antoine Nollet was trained in theology and called himself “abbe” until the end of his life, it was his scientific contributions that made him famous. Although he was head of a monastery, he spent a great deal of time on the investigation of electricity and became one of the noted authorities of his time. One of Nollet’s first accomplishments was to draw new maps of the world, based on the results of recent Dutch and English expeditions.

Jean-Antoine Nollet, who taught physics to the French royal children, designed and assembled this pair of globes, which show maps of the earth’s surface and skies. Globes frequently adorned the libraries of the aristocracy, lending an air of scholarly respectability in an age when uncharted territories around the world were being mapped and new traderoutes established. They frequently appeared in eighteenth-century portraits but were usually supported on simple turned columns. These examples, with their red and yellow lacquered stands decorated with Chinese figures, are exceptionally elaborate and may have been made to match similarly lacquered furniture.

Nollet designed and assembled the Terrestrial Globe shown below, which shows a map of the earth’s surface. In 1728 he dedicated it to the duchesse du Maine, the wife of Louis XIV’s eldest illegitimate child. The duchesse was Nollet’s most important patron and aunt to the comte de Clermont, to whom the celestial globe is dedicated. Louis Borde, the engraver of the map, also sponsored the costly printing process.

He was the publisher who provided the money needed for the engraving of the copper plate, supervised the different stages of printing and the distribution of the prints, and remained in principle the owner of the plate. Globe made by Nollet, map by Louis Borde, engraver, Paris, 1728. Wood painted with vernis Martin; papier mâche; printed paper; bronze. The inscription explains that this terrestrial globe was made with the latest and most exact observations approved by the Academy of Sciences in Paris, in 1728. The globe was dedicated to the duchesse du Maine by her humble and obedient servant Monsieur Nollet.

Terrestrial Globe

Nollet designed and assembled the Celestial Globe shown below, which shows a map of the night skies. He dated the globe 1730 and dedicated it to Louis de Bourbon-Conde, comte de Clermont. Clermont was an important patron of the arts who became protector of the Societe des Arts in 1728. This was a new organization established to provide collaboration between the arts and sciences; painters, sculptors, astronomers, clockmakers, architects, and goldsmiths were all members.

Globe made by Jean-Antoine Nollet, map engraved and printed by Nicolas Bailleul the Younger, engraver, Paris, 1730. Wood painted with vernis Martin; papier mâche; printed paper; bronze. The inscription states that this celestial globe’s design was based on the latest and most exact research. The name of the engraver , Bailleul the younger, is at the bottom of the cartouche. The globe is supported on a lacquered stand that shows cartouches decorated with Chinese figures, trees, and rocks ingold or silver varnish on a red ground.

Celestial Globe

Soon love of science became uppermost and together with Du Fay and Reaumur he devoted himself to the study of physics and especially to research work in electricity. Abbe Nollet was the first to recognize the importance of sharp points on the conductors in the discharge of electricity. This was later applied practically in the construction of the lightning-rod. He also studied the conduction of electricity in tubes, in smoke, vapours, steam, the influence of electric charges on evaporation, vegetation, and animal life.

In 1734 Nollet went to London and was admitted into the Royal Society. In 1735 he started in Paris, at his own expense, a course in experimental physics which he continued until 1760. He became the the first professor of experimental physics at the University of Paris. Through his contacts with Societe des Arts (the Society of Arts), he met members of the aristocracy who eventually became his patrons and friends. A contemporary wrote of him, “Only the carriages of duchesses, peers, and pretty ladies can be seen before his gates.” In 1738 Cardinal Fleury created a public chair of experimental physics for Nollet.

In 1739 he entered the Academy of Sciences, becoming associate member in 1742, and pensionary in 1758. In April, 1739 the King of Sardinia called him to Turin to instruct the Duke of Savoy, and to furnish the instruments needed for the new chair of physics at the university. After lecturing a short time at Bordeaux, he was called to Versailles to instruct the dauphin in experimental science.

In 1745 Nollet developed a theory of electrical attraction and repulsion that supposed the existence of a continuous flow of electrical matter between charged bodies. Nollet’s theory at first gained wide acceptance, but met its nemesis in 1852 with the publication of the French translation of Franklin’s “Experiments and Observations on Electricity”.

Franklin and Nollet found themselves on opposite sides of current debate about the nature of electricity, with Franklin supporting action at a distance and two qualitatively opposing types of electricity, and Nollet advocating mechanical action and a single type of electric fluid. Franklin’s argument eventually won and Nollet’s theory was abandoned.

In 1748 Nollet invented one of the first electrometers, the electroscope, which showed the presence of electric charge by using electrostatic attraction and repulsion. Nollet is reputed to be the man who first applied the name”Leyden jar” to the first device for storing electricity.

There are various types of electroscopes. The most common has a cylindrical metal case closed by two round, flat, glass faces. A charge sensor is mounted within the case and electrically insulated from it and is joined to an external terminal by a conductor, e.g., a metal rod. The sensor consists of two leaves of metal foil (usually gold) or a metal vane mounted so that it can freely rotate about a metal rod.

If a negatively charged body is brought near the terminal of the electroscope, it will cause electrons to be repelled into the sensor; a positively charged body attracts electrons out of the sensor. In either case a net charge is induced on each part of the sensor, and the two leaves will fly apart or the vane will swing away from the rod. It the electroscope is given a known charge by conduction, e.g., by touching its terminal with a negatively charged rod, it can then be used to identify an unknown charge.

If the unknown charge is like that on the electroscope, when it is brought near the terminal the leaves or vane will move even farther; while if it is opposite that on the electroscope, the leaves or vane will fall toward the uncharged, neutral position. The charged electroscope can also be used to detect ionizing radiation. The charge on the sensor will be neutralized by oppositely charged ions formed by the radiation from the surrounding air molecules; the rate of discharge provides an indication of the intensity of the radiation.

Osmotic pressure, the pressure that develops in a solution separated from a solvent by a membrane permeable only to solvent, was first described by Abbe J.A. Nollet. Osmosis was discovered by Nollet in 1748 with a container, filled to the brimwith alcohol and closed by a pig’s bladder, which had stood for several hours in water (to protect the alcohol against entry of air). The bladder had admitted the water into the container, but only very little alcohol. As water and alcohol were being exchanged, that is, the container closed with the pig’s bladder contained water and was below alcohol, the pig’s bladder vaulted concavely into the water container. It had let water escape and allowed only a little alcohol to enter. His discovery of the osmosis of water through a bladder into alcohol was the starting-point of that branch of physics.

Passing this charge to another person

Nollet, tutor of the royal family and professor at University of Paris, is explaining the two kinds of electricity of Du Fay as two kinds of”fluid”, one vitreous and the other resinous. The picture shows an experiment of Nollet in a salon. A lady charged by an electrostatic machine will transmit the electric shock to her lover (insulated from earth) by a finger.

Jean-Antoine Nollet, the Abbot of the Grand Convent of the Carthusians in Paris decided to test his theory that electricity traveled far and fast. He did the natural thing on a fine spring day in 1746, sending 200 of his monks out in a line 1 mile long. Between each pair of monks was a 25-foot iron wire. Once the reverend fathers were properly aligned, Nollet hooked up a battery to the end of the line and noted with satisfaction that all the monks started swearing, contorting, or otherwise reacting simultaneously to the shock.

A successful experiment: an electrical signal can travel a mile and it does so quickly. Of course, this is the kind of experiment you can only run once as your monks may prove less-than-cooperative the second time around. So, in another demonstration he discharged a Leyden jar in front of King Louis XV at Versailles by sending current through a chain of 180 Royal Guards. The King was both impressed and amused as the soldiers all jumped simultaneously when the circuit was completed.

Jean-Antoine Nollet was appointed professor of experimental physics at the Royal College of Navarre, in 1753. By 1758 he was named “Physics Teacher to the Royal Children” and established Cabinet des Physiques (the Physics Cabinet) for Louis XV, king of France. In 1761 he taught at the school of artillery at Mezi’res. Nollet was also a member of the Institute of Bologna and of the Academy of Sciences of Erfurt. He was calm and simple in manner, and his letters and papers showed that he had been devoted and generous to his family and his native village.

This electrostatic machine (shown above) described by Nollet (ca. 1740) was a typical example of electrostatic friction machines popular that time. Several kinds of them are shown below (illustrations from a Nollet’s book):

Nollet’s books

Nollet contributed to the “Recueil de l’Academie des Sciences” (1740-67) and the “Philosophical Transactions of the Royal Society”; his larger works include among others: “Programme d’un cours de physique experimentale” (Paris, 1738); “Lecons de physique experimentale” (Paris, 1743); “Recherches sur les causes particuli’res des phenomenes electriques” (Paris, 1749); “L’art des experiences” (Paris, 1770). He also pubished some other important books.

Recherches sur les Causes Particulieres des Phenomenes Electriques, l’Abbe Nollet, 1753

Nollet’s Recherches (above left) provides one of the earliest detailed treatise on electricity. His Lettres sur l’Electricite (above right) contains his correspondence with Benjamin Franklin by whom he attacks the electric theories. ‘Nollet recognized these menaces and replied in an amusing set of “Lettres sur l’electricite (1753)”, containing a wealth of counterexamples which drew their strength from Franklin’s occasional obscurities, imprecision’s, exaggerations, and inappropriate appeals to traditional effluvial models” (and which were very important to Franklin’s research).

Nollet’s experiments on electricity and the human body; engravings from his book, 1746

Abbe Nollet as early as 1750, showed the astonishing efficiency of electrostatic spraying. This picture shows his electrostatic spaying experiment. High voltage d.c. is generated by the rotating glass ball (rubbed by hand!) and distributed to the various spraying devices by the insulated chain.

Jean-Antoine Nollet has designed and described in his books many other instruments, e.g. a pyrometer, a fire pump, a press, etc.:

Nollet’s Pyrometer

This model of pyrometer, according to the Catalogo de Instrumentos de Fisica prepared by Professor J.H. Figueiredo Freire, was designed by Jean Antoine Nollet. The apparatus has the peculiarity of having a circular calibrated scale which the pointer moves over, orientated in a vertical plane, leaving visible all the mechanism of cogwheels and shafts. This makes it possible to observe its working during the expansion of the bar heated by four little night lights. It therefore makes a magnificent instrument for instructive purposes. The dial, 17,7 cm in diameter, is divided into six sectors, each subdivided into 50 equal parts.

Apart from this fixed scale, the apparatus has a second circular movable scale. This is divided into fourteen equal parts marked next to the periphery of a cogwheel, 6 cm in diameter, that engages with the teeth on the axle of the main dial. By means of this mechanism, this movable scale turns together with the pointer of the instrument, permitting the number of turns it makes to be counted. For this, a vertical needle placed in front of the movable scale is used as a reference.

This instrument is extraordinarily sensitive. The mechanism of cogwheels, levers and shafts, permits direct observation of the otherwise imperceptible expansions of the bar, via the pointer of the apparatus. The experimental studies carried out with this type of apparatus did not permit a relationship to be obtained between the expansion of the bars and the temperature. The bars used were all the same length and the experiments tried to compare the expansion of bars of different materials during a determined period of time. In addition to its use in the experimental study of the linear dilation of bodies, the instrument is also an outstanding example of mechanics.

This is a precision instrument designed to measure the variation of length of a small metal bar, when appropriately heated. This instrument was created and described for the first time by Petrus van Muschenbroek, who called it a “Pyrometer”. It was originally designed not to study heat but the thermic expansion of metals.

Those studies were initially developed and carried out until the end of the 18th century by clockmakers, whose production progress depended also on adeguate knowledge of the thermic properties of the metals they were using, particularly for those concerning the pendulum. In a catalogue of the early 19th century the dilatometer is described as a “brass machine, which is enclosed in a glass cylinder, to show the action of heat on metal objects, called the pyrometer”. The device is attached to an elegant mahogany support, which has a drawer in which the different metals bars could be stored.

A mobile warmer entirely of brass with six wicks heat the bar. This is attached at one extremity to a small brass column by means of a brass screw and it is free to expand by dilatation at the other extremity, thereby acting up on the mechanisms that amplify the elongation. The brass mechanisms are clearly visible under a protecting glass cylinder. The dilatations of the metal to be examined are recorded on a silver-plated alloy quadrant through two light metal pointers.

The less precise pointer, which moves along a smalle fissure placed vertiacally along the quadrant, records a maximum difference of 4 mm on a scale with eight 0.5 mm-marks. The more precise one is a pointer that rotates on circular scale that is divided into two hundred 2,5 m-marks. Even the 0.5 m-marks are easily read on the scale. On the quadrant there is inscribed “Lana & Turin”. The burner is filled with “wine alcohol” and the bar is heated. As the bar is warmed, the rising and lifting mechanisms are triggered and the movement is henceforth transmitted to the aforementioned scales. It still works perfectly.

This model of a fire pump constructed on the basis of a system described by Nollet in his “Lecons de Physique Experimentale”, is basically composed of two vertical cylinders, inside each of which is a piston which can be moved. Each piston is connected by means of a joint to one of the arms of a lever which, when manipulated, effects a rising and falling movement in a vertical plane.

A circular tube leads from the bottom of each cylinder into a reservoir of water. There is a valve at the junction between the tube and the inside of the cylinder that opens when the piston is pulled upwards and closes when it descends. When the piston rises, the pressure inside the cylinder decreases, permitting the entry of water which rises through the tube, filling the cylinder. When the piston descends, the water admission control valve closes. Simultaneously, a second valve in the side of the cylinder and near to the base, opens and sends water through into a glass receptacle. The communication between the cylinder and this receptacle is made through a brass tube. This valve stays open during the descent of the piston inside the cylinder, thus transferring the water to the glass reservoir situated between the two cylinders.

Working simultaneously, the two cylinders operate in such a way that while one of them pushes water from the reservoir situated in the lower part of the pump, the other transfers the water inside it into the glass reservoir. A tube which is curved at the end leads out of the base of this reservoir, fitting into a leather hose, through which the water is expelled under pressure.

The system described above, mounted on a wooden structure, was used in lessons on the mechanics of fluids and constitutes a magnificent model of a pump which was used to combat fires over many years.

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