Biographical encyclopedia
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326 [486] BABINET
WHEWELL [487] tors could travel freely in the East. He began the study of medicine with a course in chemistry, fell under the influence of Strohmeyer [411] and made up his mind to stay home and become a chemist. By 1819 he had discovered that com pounds of similar composition tend to crystallize together, as though the atoms of one intermingled with the atoms of the other, through the similar design of their structure. This is the theory of isomorphism. In reverse, one could say that if two compounds crystallize to gether, they are of similar structure. Then, if the structure of one is known, that of the other can be surmised. Berzelius [425] made use of this no tion in his atomic weight determinations, and Mitscherlich went to Stockholm to study under him. On his return to Ger many in 1821 he was elected to the Berlin Academy of Sciences and given a professorial appointment at the Univer sity of Berlin holding a position held a few years earlier by Klaproth [335]. In 1828 he was elected a foreign member of the Royal Society and the next year received the Royal Medal of the Society for his discovery of isomor phism. Mitscherlich went on after that to do considerable work in organic chemis try. In 1834, for instance, he synthesized nitrobenzene. Mitscherlich was an excellent lecturer and incorporated his lectures into a suc cessful and highly regarded textbook of chemistry, first published in 1829. [486] BABINET, Jacques (bab-ih-nayO French physicist
1794
Died: Paris, October 21, 1872 Babinet, the son of the town mayor, was aimed for the law but chose science. In 1820 he was a professor of physics at a college in Paris. He proved to be an excellent popularizer of science, writing and lecturing on a wide variety of topics. He invented a number of scientific in struments, notably a device for measur ing the angles of crystals. He is best remembered, however, for a suggestion he made in 1827 concerning, standards of measurement. Until then, men had used trivial ob jects as standard measures, the lengths of arms or feet, the weights of ears of grain, and so on. Even the metric sys tem, first established at about the time of Babinet’s birth, made use of the earth’s circumference for establishing the unit of measure, a standard that could not be certainly measured and was in any case not the expression of natural law. Babinet suggested a true standard that was indeed tied to unalterable natural properties—the wavelength of some par ticular kind of light ray. In 1960, a century and a third after the suggestion was made, technology had advanced to the point where wavelength measurements were sufficiently precise for the purpose. The unit of length is now tied to the unalterable behavior of a particular kind of xenon atom. [487] WHEWELL, William (hyoo'ul) English scholar Born: Lancaster, May 24, 1794 Died: Cambridge, March 6, 1866 Whewell was the son of a master car penter. Whewell’s father assumed his son would follow in the business, but the boy’s intelligence was clearly such that it seemed best to send him to school. Whewell entered Cambridge in 1812 and remained there the rest of his life, getting his master’s degree in 1819 and becoming an Anglican clergyman. He interested himself in the philoso phy and history of science. He did some direct work in science himself, adding significantly to the understanding of tides, and inventing an anemometer for measuring direction and pressure of the winds one which, with some modifica tion, is still used today. Whewell also labored with Peacock [472], John Her- schel [479] and Babbage [481] to reform British mathematics. He is best known, however, for the scientific terms he coined. He corre sponded with Faraday [474] and, in discussing Faraday’s findings, he sug
[488] MADLER
PAYEN [490] gested such words as “ion,” “anode,” and “cathode.” He also invented the terms “Eocene,” “Miocene,” and “Plio cene” as names for geologic eras. Most important of all, perhaps, he was the first to use the terms “scientist” and “physi cist.”
[488] MADLER, Johann Heinrich (med'ler) German astronomer
Madler was a seminary teacher, who grew interested in astronomy when the great comet of 1811 appeared in the sky. He met Beer [499], who was rich enough to maintain a private observatory, and that gave Madler his chance. He worked with him in the preparation of his map of the moon, and his ability became so obvious that he was allowed to work at the Berlin Observatory under Encke [475],
In 1841, Madler published Popular Astronomy, a book intended for the lay man; it proved a success and went through six editions in his lifetime. He also wrote a massive two-volume history of astronomy. [489] PANDER, Christian Heinrich (pahn'der) Russian zoologist Born: Riga, Latvia, July 24, 1794 Died: St. Petersburg (now Lenin grad), September 22, 1865 Pander was from the Baltic provinces of Russia, where the ruling classes were of German descent. He was the son of a wealthy banker and entered the Univer sity of Dorpat (largely German in fac ulty and student body) in 1812. In 1814 he went on to Berlin and then to Gottin gen for further studies and there he met Baer [478], In his discussions with Baer and others the problem of the chick embryo arose. Unlike mammalian embryos, hidden within the mother’s body, chick embryos could easily be studied within the egg. Pander took his M.D. at Wurzburg in 1817 and then proceeded to study the chick embryo. He discovered and de scribed the three layers that formed in the early development of the embryo and described them in a paper published in 1817. Pander, in this paper, is considered to have founded the science of embryology; but he never continued his researches, spending most of his later life in travels through western Europe and through Russia. However, Baer, who read Pander’s paper, carried on magnificently. [490] PAYEN, Anselme (pie-ohnO French chemist Born: Paris, January 6, 1795 Died: Paris, May 12, 1871 Payen was the son of a lawyer turned industrialist who established factories for the production of chemicals, particularly ammonium chloride. Payen studied first under his father and then, in the chaotic days following the fall of Napoleon, under Vauquelin [379] and Chevreul [448]. At the age of twenty he was put in charge of a borax-refining plant by his father. Borax was virtually a monopoly of the Dutch, who obtained it from the East Indies. Payen devised a cheaper method, preparing borax from boric acid (a mineral available in Italy), and broke the monopoly, selling borax at one-third the Dutch price. In 1820 his father died and Payen took full charge. He turned his attention to a factory engaged in the refining of sugar from sugar beets, and in 1822 in troduced the technique of decolorization through the use of animal charcoal. This has been a popular device among chem ists for removing large-molecular impuri ties ever since. Charcoal, the adsorptive properties of which were first put to use by Payen, was eventually to find a place in the gas masks of World War I. Through the sugar beet Payen grew in terested in agricultural chemistry. In 1833 he separated a substance from malt extract that had the property of hasten ing the conversion of starch to sugar. He called it diastase. This was an example of the organic catalysts within living tis
[491] EHRENBERG WEBER
sue, which eventually came to be called enzymes—a name invented half a cen tury later by Kühne [725]. Diastase was the first enzyme to be prepared in concentrated form and its name set the fashion for using the suffix “-ase” to name enzymes generally. The next year he began a series of researches during the course of which he separated a substance from wood that seemed to have the same general consti tution as starch. He obtained it from all sorts of wood, and because it existed in the cell walls he named it cellulose. This set the fashion of the “-ose” suffix in the naming of carbohydrates. In 1835 Payen abandoned business and accepted a post as professor of in dustrial and agricultural chemistry at the ficole Centrale des Arts et Manufac tures, and spent the rest of his life in research. In his old age he had the sorrow of witnessing the disastrous end of the rule of Napoleon HI in the flames of the Franco-Prussian War. Despite his age he refused to leave Paris as the Prussians approached and exerted his specialized knowledge to help feed the besieged and starving city. He died shortly after the final French defeat, just in time to avoid the final humiliation of the crushing of the Paris Commune, when the French army, unable to defend France against the Prussian invaders, contented itself with shooting down Parisians. [491] EHRENBERG, Christian Gottfried (ay'ren-berg) German naturalist Born: Delitzsch, Saxony, April 19, 1795
Died: Berlin, June 27, 1876 Ehrenberg, the son of a magistrate, was another one of those who, intended for a clerical life by his parents began a course of study to that effect and then switched to science. He obtained his medical degree in 1818 and in his doc toral dissertation dealt with fungi and their reproductive processes, showing their origin in spores. In 1820 he took part in an archae ological expedition through Egypt and neighboring countries, and collected enormous numbers of specimens of plants and animals. It was a harrowing and ill-organized expedition and Ehren berg was, in fact, the only survivor. As a result he was appointed to professorial status in zoology at the University of Berlin.
In 1829 he joined Humboldt [397] in the exploration of Siberia under the sponsorship of Tsar Nicholas I, and again he did excellent work in natural history. He made a special study of pro tozoa, of coral, of the one-celled plank ton in the surface layers of the ocean. He was the first to study fossils of mi croorganisms in the rocks. Ehrenberg pioneered the detailed study of the invertebrates, particularly the smaller ones, but he was hampered by his belief that even the smallest or ganisms had systems of organs analogous to those of large organisms. He therefore did not accept the cell theory in full and, of course, he did not accept evolution. [492] WEBER, Ernst Heinrich (vay'- ber) German physiologist Born: Wittenberg, Saxony, June 24, 1795
Died: Leipzig, Saxony, January 26, 1878
Weber, the son of a professor of theol ogy, grew interested in science through contact with Chladni [370], a family friend. Weber obtained a medical degree from the University of Wittenberg in 1815 and was a professor of anatomy at the University of Leipzig from 1818, but he was primarily interested in physiology. In the 1830s he found that the minimum difference in intensity that could be dis tinguished between two sensations of identical kind bore a constant rela tionship to the total intensity of sensa tion.
For instance, suppose a person could just distinguish between a 9-ounce weight and a 10-ounce weight. This would seem to indicate that he could sense the added weight of one ounce and could therefore distinguish between a 90-ounce weight and a 91-ounce weight.
[493] CAVENTOU
BRAID [494] This is not so. He will be able only to distinguish between a 90-ounce weight and a 100-ounce weight. It is not a difference of 1 gram or 10 grams that is important, but the difference of 10 per cent of the total weight. In the same way, in telling the difference between intensities of light or sound, difference in temperature or pres sure, it is the percentage difference and not the absolute difference that counts. This is widely known as the Weber- Fechner law because it was Fechner [520] who popularized Weber’s discov ery.
The law is not exact but it served as the groundwork for all kinds of experi mentation into the manner in which the human being senses the environment about him and how he interprets his sense impressions. Weber by his observa tion may be said to have founded experi mental psychology and introduced the workings of the mind into the realm of the natural sciences. This did not, of course, rob these workings of their mys tery or make psychology as objective a science as physics. Indeed, Weber’s con temporary Braid [494] was, in his work, laying the groundwork for a treatment of the mind that was far removed from the experimental methods of the physical sciences. Weber had a younger brother, Wil helm Eduard Weber [540], who was as noted as himself, but in the field of phys ics rather than physiology. [493] CAVENTOU, Joseph Bienaime (ka-vahn-too') French chemist
June 30, 1795 Died: Paris, May 5, 1877 Caventou was the son of a pharmacist and followed in his father’s profession. His education was interrupted when, in an outburst of patriotism, he joined Na poleon’s army after the latter had re turned from Elba. However, the defeat at Waterloo quickly followed and Ca ventou returned to his studies. In 1817 Caventou formed his partner ship with Pelletier [454], and together they isolated chlorophyll, strychnine, quinine, caffeine and many other sub stances.
Caventou did not accomplish much after Pelletier’s death, but he held a post as professor of toxicology at the Ecole de Pharmacie. [494] BRAID, James Scottish surgeon Born: Rylawhouse, Fifeshire, 1795 Died: Manchester, England, March 25, 1860 Braid was educated at the University of Edinburgh and practiced surgery in Manchester. In 1841 he attended some exhibitions of mesmerism, the phenome non discovered by Mesmer [314], which had been discredited for its elements of mysticism. Braid was very skeptical of the whole matter but he tried some ex periments of his own and began to think the phenomenon was real. A person could indeed be put into a trancelike state resembling sleep but differing in that he was quasi-conscious and extraor dinarily open to suggestion. Braid recognized that it was not in duced by animal magnetism but was rather a suspension of the conscious mind, induced by its having been forced into weariness through repetitive stimuli. He called the state “hypnotism,” from the Greek word for “sleep.” Despite the fact that he damaged his reputation by going too far in his new born enthusiasm for the pseudosciences by also taking up Gall’s [371] phrenol ogy, Braid eventually managed to con vince others of the reality and usefulness of hypnotism. Broca [653] in particular took the notion favorably. Hypnotism can be used to make the conscious mind unresponsive to pain, but the coming of Morton’s [617] chemical anesthesia decreased the importance of hypnotism in this respect. Hypnotism, by putting aside the conscious mind, re vealed poorly understood and almost frightening depths beneath, and a gener ation later, neurologists up to and in cluding Freud [865] were to use it to treat mental disorders. Freud was to re 330 [495] CLAUS
CARNOT [497] place it with other methods but hyp notism still has its medical uses, and (shades of Mesmer) will always be pop ular as a theatrical demonstration de signed to amaze and amuse. [495] CLAUS, Carl Ernst (klowz) Russian chemist Born: Dorpat, Estonia (now Tartu, Estonian SSR), January 23, 1796
Claus was a Balt of German descent, who was apprenticed to a pharmacist in 1810 after he had been left an orphan. In 1815 he entered the University of Dorpat, passed his examination, and in 1826 established practice as a pharmacist in Kazan. In these early years, he was particu larly interested in botany and the plant forms of the Russian steppes but he grew interested in chemistry, returned to Dor pat, received his master’s degree in chemistry, was appointed to the first pro fessorship in chemistry at the University of Kazan in 1838. Four decades before, men such as Tennant [375] and Wollaston [388] had identified dense, inert metals related to platinum in properties, and five, includ ing platinum were now known: plati num, osmium, iridium, palladium and rhodium. One and only one remained to be discovered and Claus managed the job in 1844. From 900 grams of residue out of which these known metals had been extracted, Claus isolated six grams of the sixth. He named it “ruthenium” from the Latin name of Russia. [496] QUETELET, Lambert Adolphe Jacques (ket-layO Belgian astronomer and statis tician
Quetelet studied mathematics under Laplace [347]. In 1814 he was appointed professor of mathematics at Gent Uni versity and later supervised the con struction of the Royal Observatory in Brussels. From 1828 until his death he was director of the observatory. His greatest contribution was in the application of statistical methods (with which, as a physical scientist and mathe matician, he felt at home) to the study of human beings. He recorded the chest measurements of Scottish soldiers, the height of French army draftees, and other such items and found these varied from the average in the same manner one would expect if one were plotting the fall of dice or the scatter of bullet holes about a bull’s-eye. He noted this first in 1835. Later he used the 1846 Bel gian census for his statistical analysis. In doing so, he worked out many of the rules that govern modem census-taking. He graphed the results, plotting the measurements against frequency of oc currence, and got a bell-shaped curve. (This sort of curve was used so often by Gauss [415] that it is often called a Gaussian curve.) Randomness invaded the human realm, and in one more way life (and humanity in particular) was shown to follow the same laws that govern the in animate universe. The concept of the “average man” grew out of Quetelet’s work, as well as the “vital statistics” that govern the size of insurance premiums. Nevertheless humanity as a whole did not form a homogeneous group center ing on the average, but could be divided into subgroups, as Retzius [498] demon strated. [497] CARNOT, Nicolas Léonard Sadi (kahr-nohO French physicist Born: Paris, June 1, 1796 Died: Paris, August 24, 1832 Carnot came of a distinguished French family. His father had been a leading government figure under the First Re public and under Napoleon I. He had been called the Organizer of Victory be cause of the manner in which he man aged to train and equip the raw recruits called to arms against the circling hostile powers of Europe. Carnot’s younger brother was a politician of liberal views who was later to oppose Napoleon III. Download 17.33 Mb. Do'stlaringiz bilan baham: 
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