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471 [718] BABYER
LOCKYER [719] while the cells were alive could continue beating even when removed from the body, and Ringer discovered that small amounts of other ions added to the so dium chloride of a salt solution would keep the heart beating for longer. He found that small amounts of potassium and calcium ions in the solution would keep not only hearts, but other isolated organs, functioning for a long time. As a result, Ringer’s solution came to be much in demand in physiological lab oratories, and the study of the inor ganic content of body fluids was greatly accelerated. [718] BAEYER, Johann Friedrich Wil helm Adolf von (bay'er) German chemist
20, 1917 Baeyer was the son of a Prussian gen eral and a Jewish mother who had been converted to Christianity. Baeyer’s father was interested in science, had worked for Bessel [439] and had become chief of the Berlin Geodetical Institute in 1870. Young Baeyer, meanwhile, had studied chemistry at Heidelberg under Bunsen [565] and Kekule [680] and had ob tained his Ph.D. in 1858. In 1863 he discovered barbituric acid, parent compound of well-known “sleep ing pills” of today. He is supposed to have named it for a girl friend (Bar bara) of the moment. The chemistry of the barbiturate compounds was worked out in further detail a generation later by Emil Fischer [833]. When Hofmann [604] returned to Germany in 1864, Baeyer competed with him in dye re search. His student Graebe [752] synthe sized alizarin and he himself synthesized indigo. The latter feat led to the synthe sis of the dye (very similar to indigo in chemical structure) that the men of Tyre had once manufactured for the use of royalty. In 1872 he became professor of chem istry at the University of Strasbourg and in 1875 he was called to the University of Munich to succeed Liebig [532], who was now dead. Baeyer then established a laboratory that was to become as famous as Liebig’s had been. Working with no less a person than Perkin’s [734] son, Baeyer devised new methods for forming small rings of carbon atoms and worked out a theory of such rings that is still called Baeyer’s strain theory. This helped explain why rings of five atoms or six atoms were so much more common than those of fewer than five or more than six. In 1905 Baeyer was awarded the Nobel Prize in chemistry, in recognition of his work in synthetic organic chemis try, which did much to establish Kekule’s structural theories, and, par ticularly, for his synthesis of indigo.
English astronomer Born: Rugby, Warwickshire, May 17, 1836 Died: Salcombe Regis, Devon shire, August 16, 1920 Lockyer, the son of a surgeon- apothecary, began his career in 1857 as a clerk in the War Office. Astronomy, however, became his hobby after he had met an amateur astronomer and found himself fascinated by what the other had to say. Lockyer obtained a telescope and eventually astronomy became his profes sion. He was particularly interested in the sun and in the 1860s pioneered (simulta neously with Huggins [646] and Young [712] but independently of them) in the study of solar spectra. He was the first to study the spectra of sunspots, something he initiated in 1866. He was also interested in prominences, huge gouts of flaming gas hurled out of the sun’s outer layer (which Lockyer named the chromosphere). Ordinarily they were only visible during an eclipse, when the blazing light of the solar disc was obscured and the prominences glowed red beyond the obscuring edge of 4 7 2
[719] LOCKYER
ALLBUTT [720] the moon. In 1868 Lockyer demon strated that the spectra of the promi nences could be observed and studied even without an eclipse by leading light from the very edge of the sun through a prism. This discovery was announced on the same day by the French astronomer Janssen [647], who was in India observ ing a total eclipse. As a result, the French government some ten years later struck a medallion showing the heads of both scientists. By that time, the two men had made a much more dramatic discovery at the same time, this time in cooperation. Janssen, studying the spectrum of the sun during the eclipse, had noted a line he did not recognize. He sent a report on this to Lockyer, an acknowledged expert on solar spectra. Lockyer compared the reported position of the line with lines of known elements, concluding that it must belong to a yet unknown element, possi bly not even existing on earth. Frank land [655] agreed with him on this point. Lockyer named the element he lium, from the Greek word for the sun. Lockyer’s conclusion was dismissed by other chemists, however, as was not un reasonable, for spectroscopy was new and it still seemed risky to hang a new element in the heavens on a foundation no more substantial than a colored line revealed by a spectroscope. In fact since Lockyer’s report, many strange lines have been discovered in the light of heavenly objects and some have been at tributed to new elements named coro- nium, geocoronium, nebulium, and so on. All of these have turned out to be just old elements under unusual conditions. All, that is, but one. The one exception was helium. Nearly forty years after Lockyer an nounced the existence of helium in the sun, it was discovered on earth by Ram say [832]. Lockyer lived long enough to see himself vindicated. Lockyer, in studying spectra, an nounced in 1881 that certain lines pro duced in the laboratory became broader when an element was strongly heated. He believed that at very high tempera tures, atoms broke down to still simpler substances and that this accounted for the change in the lines. He was one of the first, after Prout [440], to venture a denial of the concept, as old as Democ ritus [20], that the atoms were indivis ible.
His view was far too simple, but the next two decades showed that atoms had an internal structure and could gain elec tric charge through the gradual chipping off of electrons with increasing heat. It was these mutilated atoms (and not new varieties of atoms) that gave rise to coronium and all the other false alarms. Lockyer was thus not only instrumental in finding a real new element in the heavens, but contributed to the debunk ing of false ones. Lockyer was elected to the Royal Soci ety in 1869 and received its Rumford medal in 1874. He was knighted in 1897, after helium was discovered on earth. He founded the famous British journal Nature in 1869 and edited it for half a century, until his death. Lockyer was not an academic. He did not receive a university appointment till 1881 and no degree until an honorary doctorate from Cambridge was awarded him in 1904. [720] ALLBUTT, Sir Thomas Clifford English physician Born: Dewsbury, Yorkshire, July 20, 1836 Died: Cambridge, February 22, 1925
Educated at Cambridge, Allbutt served as a physician at Leeds General Infirmary until 1889. In later life he was a commissioner in lunacy and then, from 1892, he was professor of medicine at Cambridge, where he remained for the rest of his long life. He was knighted in 1907.
He did good work on such purely medical problems as syphilis and angina pectoris but his greatest service was un doubtedly the invention of the one medi cal instrument used most frequently by
[721] GULDBERG
DRAPER [723] doctors, nurses, and laymen alike—the clinical thermometer. In 1866 he de signed a short thermometer no more than six inches long that reached equilib rium in only five minutes, replacing much longer thermometers that required twenty minutes to reach equilibrium. Then, and only then, did it become possible to make temperature measure ments as a matter of course and to fol low the progress of fever, as Wunderlich [592] had maintained it was important to do.
[721] GULDBERG, Cato Maximilian (gool'berg) Norwegian chemist and mathe matician
Born: Christiania (now Oslo), August 11, 1836 Died: Christiania, January 14, 1902
Guldberg, the son of a minister, was a professor of applied mathematics at the University of Christiania, and is known primarily for a pamphlet he published on March 11, 1864, in collaboration with his brother-in-law, Waage [701]. In this pamphlet, in which he extended the work of Berthelot [674], he an nounced his discovery that the direction taken by a reaction is dependent not merely on the mass of the various com ponents of the reaction, but upon the concentration; that is, upon the mass present in a given volume. Since the pamphlet was published in Norwegian, it escaped the notice of most chemists. It was translated into French in 1867 and still made no impression. Finally Guld berg and Waage published a full transla tion in Germany in 1879 and Ostwald [840] recognized its importance. By then, Van’t Hoff [829] had described this law of mass action at least partially. The pri ority of Guldberg and Waage was, how ever, recognized. When Gibbs’s [740] work became known it could be seen how the law of mass action followed naturally from the basic principles of chemical thermo dynamics. [722] WALDEYER-HARTZ, Heinrich Wilhelm Gottfried von (vahl'dy- er-hahrts) German anatomist Born: Braunschweig (Bruns wick), October 6, 1836 Died: Berlin, January 23, 1921 Waldeyer (as he was originally named, without the hyphenation) was the son of an estate manager. He studied at Got tingen and obtained his medical degree from the University of Berlin in 1862. He is best known for his work on the nervous system. He was the first to maintain that it was built up out of sepa rate cells and their delicate extensions. (The individual cell plus its extensions he called a neuron and his views were named the neuron theory.) He pointed out that the extensions of separate cells might approach closely but did not actu ally meet, much less join. Waldeyer is another one of those sci entists who contributed a key word to the scientific vocabulary. It was he who in 1888 gave the name “chromosome” to the threads of chromatin material that Flemming [762] had discovered to form during cell division. [723] DRAPER, Henry American astronomer
Virginia, March 7, 1837 Died: New York, New York, No vember 20, 1882 Draper was the son of John William Draper [566]. The younger Draper was educated at the University of the City of New York (his family having moved to New York when he was two years old) and he obtained his medical degree in 1857. By that time, though he had en countered Rosse [513] during a visit to Ireland, it was astronomy that fas cinated him. In 1861 he had set up an observatory on his father’s estate at Hastings-on-Hudson and it was in astronomy, which he carried on at his own expense, that he made his fame. He served briefly with the Union army as
[724] PROCTOR
KÜHNE [725] surgeon until discharged because of poor health. Draper had begun by trying to polish a metal mirror for his telescope, but John Herschel [479] advised him that glass was much better for the purpose. Draper eventually ground about a hun dred glass mirrors. In 1872, once he had a twenty-eight-inch reflector, he tried to photograph the spectrum of the star, Vega. On the second try he succeeded and this was the first time that a stellar spectrum had ever been photographed. In 1879 Draper learned from Huggins [646] in England of the use of dry plates in photography, these being much more stable than the wet collodion plates Draper had been using. Using the dry plates, Draper was able to get stellar spectra by the score. His study of the spectrum of the Orion Nebula showed it to be a cloud of dust and gas lit by star light.
Draper died prematurely of double pneumonia, but after his death his widow established the Henry Draper Memorial at the Harvard College Obser vatory to further research on stellar spectra.
[724] PROCTOR, Richard Anthony English astronomer Born: Chelsea (London), March 23, 1837 Died: New York, New York, September 12, 1888 At Cambridge it was Proctor’s inten tion to study law, his father’s profession, but in 1863 he turned to astronomy and mathematics. His first interest was Mars, whose surface he studied, summarizing his observations in 1867 in a map on which he placed continents, seas, bays, and straits as once Riccioli [185] had done for the moon. He used English astronomers almost exclusively in naming the Martian fea tures and this roused considerable hostil ity among astronomers of other nations. Schiaparelli [714] corrected this piece of overenthusiastic nationalism. Like Beer [499], a generation earlier, Proctor saw none of the “canals” that Schiaparelli was soon to discover. In 1873 Proctor was the first to suggest that the lunar craters arose through meteoric bombardment. Until then it had been taken for granted that the craters were the result of volcanic action, but since Proctor’s time the meteor theory has been predominant even though Proctor weakened in his own support of this theory in later life. Proctor then turned to the task of popularizing astronomy in lecture tours that led him as far afield as the United States and Australia. In 1881 he settled in the United States where he remained for the last years of his life. [725] KÜHNE, Wilhelm (Willy) Frie drich (kyoo'nuh) German physiologist Born: Hamburg, March 28, 1837 Died: Heidelberg, June 10, 1900 Kiihne, the son of a prosperous mer chant, was a student of Wohler [515] and Virchow [632] and obtained his doc torate at the University of Gottingen in 1856. He worked also with Du Bois- Reymond [611], Hoppe-Seyler [663] and with Bernard [578] in Paris. In 1871, he became professor of phys iology at Heidelberg, succeeding Helm holtz [631]. He extended Bernard’s stud ies on pancreatic juice by isolating from it the ferment trypsin, which was shown to have a digestive action on protein. In that same year, 1876, Kiihne dem onstrated his vitalist position by suggest ing that the word “ferment” be restricted to those substances that, within living cells, brought about chemical reactions associated with life. The substances that could be isolated from digestive juice (which performed its work outside cells), like the pepsin of Schwann [563] and like his own trypsin, did not, ap parently, deserve the dignity of a word so closely associated with life. He suggested that these substances be called enzymes, from Greek words meaning “in yeast,” because they resembled the fer ments in living cells, notably in yeast. 4 7 5
[726] VAN DER WAALS VAN DER WAALS
The distinction was too fine, and two decades later, after Buchner’s [903] dem onstrations that the ferments within the yeast cell could work outside the yeast cell and without life, the word “enzyme” was applied to all ferments, inside and outside the cell. [726] VAN DER WAALS, Johannes Diderik (van der vals) Dutch physicist
1837
Died: Amsterdam, March 9, 1923 Van der Waals, the son of a carpenter, was largely self-taught when he entered Leiden University in 1862. His doctor’s thesis in 1872 on the nature of the gas eous and liquid phase attracted consid erable attention and set the dominant note of his lifelong researches. He was appointed professor of physics at the University of Amsterdam in 1877 and stayed there until his retirement thirty years later. His lifework represents a crucial im provement on the old classic work of Boyle [212] and Charles [343]. Boyle had discovered the relationship of pres sure and volume, while Charles had worked out with considerable accuracy the relationship of temperature and vol ume. The two relationships could be combined into a single equation: where P represents the pressure of a quantity of gas, V its volume and T its absolute temperature. The symbol R rep resents a constant. Ideally, in any given sample of gas, if any one of the three variables, pressure, volume, or tempera ture is varied, the values of the other two adjust themselves to keep the value of
R
constant. However, this is not quite true in ac tual fact. In gases such as hydrogen, ni trogen, and oxygen, it is almost true and becomes more nearly true as the temper ature of the gas is raised and the pres sure lowered. Chemists thought that for an “ideal gas” or “perfect gas” it would hold exactly, and without qualification. Van der Waals was interested in deter mining why the “perfect gas equation” did not hold exactly for real gases. He considered the kinetic theory of gases worked out by Maxwell [692] and Boltz mann [769], It could be made to yield the perfect gas equation provided two assumptions were made: that there were no attractive forces between gas mole cules, and that the gas molecules were of zero size. Neither assumption is quite correct. There are small attractive forces between gas molecules and though those mole cules may be exceedingly small, their size is not zero. Taking this into account Van der Waals in 1873 worked out a somewhat more complicated version of the gas equation, in which two more constants were introduced. These con stants were different for each gas and had to be determined by actual observa tion, since for each different gas, the molecules were of a particular size and exerted their own particular inter molecular attractions. By using the temperature, pressure, and volume of a gas at its critical point (where the gas and liquid forms become equal in density and cannot be distin guished from each other) Van der Waals worked out another equation, one in which new constants were not needed and which would hold for any gas. As a result of Van der Waals’s work, it was discovered that the Joule-Thom son effect, by which a gas cools when al lowed to expand, only holds below a cer tain temperature, one that is charac teristic for each gas. For most gases this characteristic temperature is high enough for physicists cooling gases by the Joule- Thomson effect to work freely. For hy drogen and helium, however, the charac teristic temperature is very low. The liq uefaction of those gases could not be carried through by gas expansion (the most convenient method) until the tem perature was first lowered to the requi site point by other methods. It was only then that Dewar [759] and Kamerlingh Onnes [843] were able to enter the ap proaches to absolute zero. In 1910 Van der Waals was awarded Download 17.33 Mb. Do'stlaringiz bilan baham: 
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