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[423] OKEN SILLIMAN [424]
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[423] OKEN
SILLIMAN [424] [423] OKEN, Lorenz (oh'ken) German naturalist
1, 1779
Died: Zürich, Switzerland, August 11, 1851 Oken (whose real name was Ock- enfuss) was the son of a poor farmer. He was much influenced by the philoso phy of Kant [293], and in 1803 he grew interested in and eventually became the most important member of the Na turphilosophen (“nature philosophers”) who flourished in early-nineteenth-cen- tury Germany and who had, on the whole, a deleterious effect on the devel opment of biology. Goethe [349] had announced a theory that the skull of vertebrates had origi nally been formed out of vertebrae. In 1807 when Oken was appointed a pro fessor of natural science at the Univer sity of Jena, he elaborated on this theory. It was later carried to extremes, as when the notion arose that the origi nal vertebrate had had a skeleton that looked like a centipede, with ribs and limbs attached to each vertebra. When the first several vertebrae fused to form the skull, the limbs attached fused to form the jaw. This whole notion was false, as was finally demonstrated in 1858 by Huxley [659], but it served science well in one way: It included the idea of evolution. If a portion of a backbone could change into a skull, it went without saying that one species could slowly change into an other. Oken’s views were quite mystical and obscure, and rather repellent to the ra tionalist. He considered man the summit of creation, a microcosm reflecting the macrocosm, or universe. His speculations seemed to foreshadow the cell theory and the protoplasmic basis of life, but mere speculation is easy enough and is no substitute for generalizations based on careful observation and experiment. In 1816 Oken founded an important biological journal, Isis, that not only published worthwhile papers on biology but also served as a vehicle for Oken’s nationalist views (and in those days Ger man nationalism was a liberal move ment). He was forced out of Jena as a result, giving up his position rather than submit to censorship of Isis. Eventually, though, he found a haven in Switzerland. He performed an even greater service by founding an important German scientific society of which Humboldt [397] became a leading light. He also ad vocated annual meetings of biologists, physicians, and natural historians, so that views on the life sciences could be made public and communicated through out the world of scholarship. Such meet ings in virtually all branches of science are now a common (and, indeed, in dispensable) feature of the scientific way of life. [424] SILLIMAN, Benjamin American chemist Born: North Stratford (now Trumbull), Connecticut, August 8, 1779
November 24, 1864 Silliman studied at Yale and obtained a degree in law in 1796. In 1802, how ever, the president of Yale asked the young lawyer to accept a post as profes sor of chemistry. This was not because Silliman was qualified, but because there were no chemists to appoint. Silliman accepted and went to the University of Pennsylvania for training. There he met Hare [428], He then com pleted his training by studying in En gland, where he met Davy [421], among others. He returned in 1804 to serve half a century at Yale, and established its graduate school, which awarded its first Ph.D. in 1861. He was never a great ex perimental chemist, but he was an inspir ing teacher who made chemists out of others and who by public lectures popu larized science generally in the young na tion. In 1806 he introduced Priestley’s [312] soda water into America. In 1807 he and a colleague observed a meteorite fall. At the time the general scientific opinion was that tales of stones from heaven ranked with ghost stories. In fact,
[425] BERZELIUS BERZELIUS
Thomas Jefferson [333], then president of the United States and an amateur sci entist, observed, concerning Silliman’s re port, that it was easier to believe that two Yankee professors would lie than that stones would fall from heaven. Biot [404] had already demonstrated the exis tence of meteorites four years earlier, and a gigantic meteor shower a quarter century later was to make the whole scientific world meteor-conscious. In 1818 Silliman founded the Ameri
was an influential factor in the develop ment of American science and which was popularly known as “Silliman’s Jour nal.” [425] BERZELIUS, Jons Jakob (bur- zeefiee-us) Swedish chemist Born: Vaversunda Sorgard, August 20, 1779 Died: Stockholm, August 7, 1848 Berzelius lost his father, a clergyman- schoolmaster, when four years old, and his mother when nine. During his mother’s widowhood, she had married again, however, and the stepfather, an other clergyman, saw to the young man’s education. Berzelius attended medical school at Uppsala, where he studied under Ekeberg [391], among others. However, he was an indifferent student, at least as far as medicine was con cerned. Chances are he would have flunked out had it not been for his un usual proficiency in physics. At any rate, he obtained his medical degree in 1802 and was so proficient in chemistry as well (he had been introduced to that subject by his stepbrother) that he domi nated the field in his later years. He was a full professor by 1817. About 1807, working with Hisinger [390] to begin with, he determined the exact elementary constitution of various compounds. By running two thousand analyses over a period of ten years, he advanced so many examples of the law of definite proportions first announced by Proust [364] that the world of chem istry could no longer doubt its validity. This in turn helped place Dalton’s [389] atomic theory (which Berzelius was among the first to accept) on a firm footing and Berzelius next devoted him self to investigating the one key property of atoms that was then appreciated—the atomic weight. In this task he had the help of generalizations advanced by his contemporaries Dulong [441] and Petit [476] and by Mitscherlich [485]. These generalizations, combined with the law of combining volumes advanced by Gay- Lussac [420], gave him enough to go on. He was able to prepare a list of atomic weights that can be considered the first reasonably accurate one in history. This table, published in 1828, is in fair agreement in all but two or three cases with the accepted values of today. Un fortunately, Berzelius did not appreciate the value of Avogadro’s [412] hypothesis and he remained in some confusion as to the distinction between atoms and mole cules. This spoiled some of the use fulness of his table and atomic weights did not come into their own until Can nizzaro [668] had had his say at the Congress of Karlsruhe in 1860, more than a decade after Berzelius’ death. Berzelius, while working with atomic weights, was made painfully aware of the tedium of forever speaking about the elements by their full names. It seemed clear to him that some sort of symbols were necessary to represent the elements, particularly in attempting to give the formulas of compounds. Dalton had used symbols composed of circles with different markings, but these were difficult to draw and to reproduce, and it was an unnecessary effort of memory to have to tie up a particular symbol with an element. Berzelius suggested, therefore, in 1813, that the initial letter of the Latin name (or the initial letter plus a second letter from the body of the name) be used as symbol. Thus, oxygen could be O, nitro gen N, hydrogen H, carbon C, sulfur S, calcium Ca, chlorine Cl, copper (cu prum) Cu, gold (aurum) Au, and so on.
The makeup of a compound could be expressed by such letters, together with subscripts where more than one atom of
[425] BERZELIUS BELLINGSHAUSEN
a given variety was present in the mole cule. Thus ammonia would be NH3, cal cium carbonate CaC03, and so on. Dal ton opposed this new suggestion, prefer ring his own system of pictographs, but he stood virtually alone. Berzelius’ sys tem was eventually adopted and now forms the international, and indis pensable, symbolic language of chemis try. Meanwhile, Berzelius was also engaged in dealing with the new wonder of the age, electricity. Shortly after Volta [337] had demonstrated how to produce a con tinuous electric current by means of a battery, Berzelius began, in 1803, to ex periment with the effects of electric cur rents upon solutions of chemicals. In this he had the collaboration of his good friend Hisinger [390]. Davy [421] was to produce the more startling results in this field, but Berzelius used his experi ments as a basis for certain interesting theories. He held, for instance, that atoms formed stable combinations that moved as intact groupings from larger combination to larger combination dur ing the course of a chemical reaction. These stable combinations he called radi cals. This view has proved correct in many ways, although Berzelius’ attempt to carry it over into organic chemistry went too far. Berzelius also developed electrical theories of molecular structure that have proved wrong but that main tained a hold on chemical thinking for decades because of Berzelius’ great pres tige. Yet it was in the attempt to explain this theory clearly that Berzelius experi enced the final impetus to work out the chemical symbols of the elements—so perhaps it was all worth it. With Hisinger, back in 1803, Berzelius had been among the first to recognize the new element cerium but was just beaten out by Klaproth [335]. Berzelius went on to discover other new elements: selenium in 1818, silicon in 1824, and thorium in 1829. By 1830 Berzelius was the great chem ical authority of the world. His textbook of chemistry, first published in 1803 and going through five editions before his death, was considered the last word. When he visited France he was pre sented to King Louis Philippe. In Ger many, Goethe [349] was proud to have lunch with him. Between 1821 and 1849 he published a yearly review of chemical progress in which he editorialized on the work of others; and when he condemned a new suggestion or experiment, it was as good as dead. This was not altogether good, for Berzelius grew conservative in his old age and held to his own ideas fiercely, all the more so when they were under at tack. He was on the wrong side in al most all the controversies of his old age, though it wasn’t till the old dictator was dead that the right side could finally es tablish itself. Berzelius’ wide-ranging in terests placed him in the midst of every branch of chemistry and many of the words that are most commonly in use now—catalysis, isomer, polymer, allo trope, halogen, protein—were introduced at his suggestion. His later life was made miserable by sickness but in 1835, at the age of fifty- six, he finally married, taking to himself a fine-looking, twenty-four-year-old wife, with whom his last decade was spent in complete happiness. On his wedding day his gift from the Swedish king, Charles XIV, was that of being made a baron. [426] BELLINGSHAUSEN, Fabian Gottlieb von (bel'lingz-how'zen) Russian explorer Born: Arensburg on the island of Oesel, Russia (now Kingisepp, Sarema, Estonian SSR), August 30, 1779 Died: Kronstadt (now Kronshlot, USSR), January 25, 1852 Bellingshausen was bom in the Baltic provinces where people of German de scent were still the landowners, the Ger mans having conquered and dominated the region in the Middle Ages. His name, to the Russians, is Faddei Fadee- vich Bellinsgauzen. He entered the Russian navy in 1789 as a cadet, when he was only ten years old, and between 1803 and 1806 he par ticipated in the first Russian cruise that circumnavigated the world. 289 [427] DOBEREINER DÔBEREINER
In 1819 he was commissioned to ex plore the Antarctic and it is on those exploits that his fame rests. In 1820 he was one of three people (the other two being an American, Nathaniel B. Palmer, and an Englishman, Edward Bransfield) who first sighted the conti nent of Antarctica. Of the three, only Bellingshausen did so south of the Ant arctic Circle. Bellingshausen also discov ered the first islands south of the Antarc tic Circle, naming them Peter I Island and Alexander I Island (now known as Alexander Island). The portion of the ocean he sailed through is called the Bellingshausen Sea in his honor. With Bellingshausen’s voyage, the world’s ice-free ocean may be considered to have been completely explored. Only the frozen polar wastes and the conti nental interiors remained. In later life, Bellingshausen became an admiral and was commander of the Kronstadt naval base at the time of his death.
[427] DOBEREINER, Johann Wolfgang (der'buh-ry-ner) German chemist
13, 1780 Died: Jena, Thuringia, March 24, 1849
Dobereiner was the son of a coachman and received very little formal education. He was apprenticed to an apothecary and read widely, however. He attended any learned lecture he could get to, and somehow managed to display sufficient ability to attract the attention of a noble man, who used his influence to obtain a position for him in 1810 as professor of chemistry and physics at the University of Jena. He obtained a doctor’s degree in that year as well. He held that position worthily for the rest of his life. He taught chemistry to Goethe [349], A more material accomplishment was his discovery of furfural. Of his two most important contri butions, one involved platinum. In 1816 Davy [421] had noted that a heated plat inum or palladium wire seemed to bring about the oxidation of organic vapors mixed with air. In the 1820s Dobereiner found the effect was sharpened if the platinum was powdered (platinum sponge). He obtained supplies of that ex pensive and hard-to-get material through the generosity of the grand duke who sponsored the university. Dobereiner went on to invent an auto matic lighter called Dobereiner’s lamp that was based on this principle. This was an arrangement whereby a jet of hy drogen could be played at will upon plat inum sponge, at which point the hydro gen would catch fire at once. It didn’t last long, for the platinum (too expen sive to begin with) was quickly fouled by the impurities in the hydrogen and stopped working. Some money might have been made out of the device but Dobereiner refused to patent it saying he loved science more than he loved money. The device, however, like the steam engine of Hero [60], foretold great things. The action of platinum was what Berzelius [425] was to name catalysis and during the course of the nineteenth century platinum was to become impor tant in industrial chemistry for bringing about certain reactions easily and quickly. A new and better method for the production of the crucial chemical, sulfuric acid, based on platinum catal ysis, was devised. (He also discovered the catalytic effect of manganese diox ide on the decomposition of potassium chlorate—a favorite demonstration of oxygen production in elementary chemis try courses.) Another of Dobereiner’s discoveries also seemed trivial to his contemporaries. It involved the fact that by the begin ning of the nineteenth century the num ber of elements that had been discovered was over fifty. Furthermore, they were of all sorts and varieties, and chemists despaired of finding order among them. In 1829 Dobereiner noted that the ele ment bromine, discovered three years be fore by Balard [529], seemed just half way in its properties between chlorine and iodine. Chlorine, bromine, and io dine, it seemed to him, possessed a smooth gradation of properties as far as 290 [428] HARE
LAËNNEC [429] color, atomic weight, reactivity, and many other matters were concerned. Even earlier he had found the same to be true of the elements calcium, stron tium, and barium, and of sulfur, selen ium, and tellurium. With the matter of bromine he thought himself ready to announce a law of triads. Unfortunately few other clear-cut cases could be found among the list of elements and for a generation Do- bereiner’s triads were shrugged off as in teresting coincidences that were of no real value, though Gmelin [457] was one of those impressed. Nevertheless they foreshadowed the periodic table of Men deleev [705], a crucial chemical advance of the mid-nineteenth century which Dobereiner did not live to see. [428] HARE, Robert American chemist Born: Philadelphia, Pennsylvania, January 17, 1781 Died: Philadelphia, May 15, 1858 Hare’s father was a brewer and much of Hare’s life was spent in managing the brewery till it failed in 1815. His early education was achieved by reading at home. In his late teens he was able to at tend lectures on chemistry. In the course of those lectures he grew interested in the possibility of attaining great heat by which to study certain chemical reac tions. He thought of hydrogen as a possi ble fuel. Using materials borrowed from the brewery, he set up a keg as a two- compartment container of hydrogen and oxygen, worked up a sheet of tin into two tubes and, in 1801, prepared the first oxy-hydrogen blowpipe. He had grown friendly with Priestly [312] and it was to him that Hare gave the first dem onstration of his device. This blowpipe was the ancestor of our welding torches of today. With his blow pipe Hare was the first to be able to melt sizable quantities of platinum. Later it was discovered that a blowpipe flame played upon a block of calcium oxide (lime) produced a brilliant white light. This was used to illuminate theater stages and we still speak of someone who faces the glare of publicity as being in the limelight. In 1809 Hare, with the backing of Silliman [424], tried to break away from the brewery and become a professor of chemistry at the University of Pennsyl vania Medical School. Since he lacked a proper medical education he was only appointed professor of natural philoso phy. The course was not a required one for medical students, so no one attended and Hare had to resign. The War of 1812 ruined the brewery business and Hare spent some years in an unsuccessful attempt to recoup his fortunes. In 1818 he finally obtained the position he wanted at the medical school. He was a successful teacher and one of the few strictly American products who in those days could be considered within hailing distance of the great European chemists. After his retirement he wrote a hovel and grew interested in spiritualism. He invented a device by which he thought he could communicate with spirits and wrote a fat volume on the subject in 1854. [429] LAËNNEC, Théophile René Hya cinthe (lah-en-nek') French physician Born: Quimper, Finistère, February 17, 1781 Died: Kerbouamec, Brittany, August 13, 1826 Laënnec, the son of a lieutenant, was left motherless at an early age and was placed in the care of his uncle, a physi cian. He was introduced to medical work and earned his medical degree in 1804. His distinction as a physician was de servedly great in his own time but he is remembered today chiefly for an inven tion so simple that Hippocrates [22] might have thought of it as easily as Laënnec. Physicians could gain important infor mation by listening to the sound of the heart, but when Laënnec, in 1816, was faced with a plump young girl with a heart condition, he thought it would be indelicate (and ineffective) to try to hear
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