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WALTER SPRING, AN EARLY PHYSICAL CHEMIST1 FABIAN LIONETTI and MILTON WAGER Boston University School of Medicine, Boston, Massachusetts
THE Belgians are known to have contributed much to the advancement of chemistry. For a nation whose population compares with that of the city of New York it is remarkable to recount the impact which many of its native-horn or adopted chemists have made in the historical literature. Beginning arbitrarily about 1830, when national independence was established, a significant list of notables could include Jean B. van Mons (1765-42), Jeans. Stas (1813-91), LouisMelsens (181486), Freidrich A. KekulB (1829-96) (who spent nine years a t Ghent), Louis Henry (1834-1913), Ernest Solvay (1838-1922), Leon Crismer (1858-1944), Fredric Su7arts (186&1940), Albert Sauveur (1863-19391, Leo H. Baekeland (1863-19441, Jean Timmermans (1882-?), and Walter Spring (1848-191 I). LP,.esented at the 117th Meeting Society, Hoston, April, 1050.
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Spring was a nineteenth century chemist of great originality and imaginative researches. He was born in 1848 (March 6), the son of a professor of physiology of the medical faculty at LiBge. His early studies were characterized by failures in classical languages and mediocre ability in letters. This inability to succeed in his education and the resultant domestic strife led him to leave his home and family and to take a position as a laborer in an applied metallurgical laboratory (a metal~rnithy).~I t was here he developed a dexterity for manipulative skills which aided greatly in his future brilliant researches. His choice of a career in chemistry was greatly influenced by Jean Stas, a family friend, and one who mas perhaps the most eminent. of Belgian men of science. Guided by the inspiration of Stas, chemical who also "sired" such other Belgian chemists as Ernest Solvay, Leon Crismer, and Louis Henry, he accomplished a successful six-year period of study in science a t Liege (1867-72), which culminated very successfully in his acquiring the Ph.D. degree in the final year. The following two years were spent at Bonn where Kekul6 and Clausius exercised profound influence on his aspirations and scientific ideals. In 1875 he returned to Liege where he was appointed teacher of theoretical physics. The following year he was named professor of organic chemistry; and in 1884 he became permanent examiner of the Militaly School of Belgium and also gained election t o the Belgian Academy. In his early career he coincidentally held the position of engineer in the Belgian Bureau of mine^.^ Spring's research endeavors were characterized by the originality of his theoretical views and the minube exactitude of his experiments; his early work reflected a strong influence of prominent men of his time-Stas, KekulB, and Clausius. His first lectures discussed the thesis of Stas on the role of hypothesis in science and proclaimed the important part which imagination has in research. In his first work one meets the influence of KekulB wherein he applied his views to the interpretation of the formula of polythionic acids and that of Clausius when he undertook the study of electrostatic phenomena in mercury-filled capillary tubes. I n 1880 he opened to students the first lahoratory of chemistry at LiBge, but his untiringdevotion to pure research, his exacting standards, and his inability to adjust himself socially led finally to clashes with the administration of
C a u r i e s y of Dr. lean T~rnrnerrnans. Univerr~iyofBrussels
welter spring
TIMMERMANS, J., "Histoire de Is, ehimie," Les Presses Universitsires de Bruxelles, Brussels, 1947, pp. 99-104. POGGENDORF, J. C., "Biographi~ch-Literarisches Handaorterbueh," Vierter Band, Leipaig, 1904, p. 1423.
NOVEMBER, 1951
the university and misunderstandings with his colleagues at the Ecole des Mimes. The result was, for Spring, a life of solitary seclusion in his laboratory. Spring's numerous and varied investigations showed him to be quite versatile and to have interests very broad in scope. He displayed a prolonged interest in the chemistry of organic and inorganic sulfur compounds, which included preparative studies on thioacetone, hyposulfurous acid, and metal sulfides. He studied the expansion of alloys with temperature and exceptions to the law of Dulong and Petit. He is remembered mainly, however, for the studies of the effects of pressure on liquid and solid systems and for extensive researches in colloids. In his work on the compression of solids he was able t o obtain pressures of 20,000 kg. per sq. cm. and demonstrated that carefully cleaned and scoured metal powder was welded into compact blocks under pressures of this magnitude. He also demonstrated that polished blocks of copper and zinc when placed in close contact and compressed produced a n intermediary layer of brass, which proved the reality of diffusion of metals in the solid state. When objections were made that the heat of compression might have raised the temperature and caused liquefaction-hence favoring the reaction of the two metals -Spring refuted these by compressing phorone (melting point 2 8 T . under a pressure of 1 atm.) and showed the compression produced a compact block without liquefaction since a lead pellet placed in the phorone was found in the same position a t the end of the experiment. He determined densities of fused solids and showed an elevation by compression which tended to a definite limit "by the abolition of pores," whereas salts of lead, zinc, aluminum, and ammonium sulfate showed an increase in specific volume with compression. The latter phenomenon was interpreted by Spring as a proof that the fluid state is a partial liquefaction involving an expansion, On the contrary, bismuth, whose specific volume diminished with fusion, contracted also when subjected to high pressure. Finally, he investigated the properties of salt hydrates and double salts and, guided by the principle of Le Chatelier, demonstrated that the volumes of these salts were greater than the sums of the volumes of the constituents, and hence decomposed under pressure. Some of his researches on the compression of powdered solids were published in Sillimau's journal (American Journal, 36, 1888), the first truly scientific journal in the United States. An interesting application of these high-pressure methods was the discovery that peat could be transformed into lignite and that pressure applied to layers of clay between which organic deposits were introduced produced schist rocks. There followed an extensive array of papers on the physical properties of water, its color, purity, and solvent action which led to numerous interesting findings and an investigation of the waters of the Meuse River was conducted in which collaborative analyses were done with Proust and Roland. Repeated analyses every day for a year were done in order to verify the
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composition of the water and determine the variation with time. Studies on the color of the waters of the river led eventually to the preparation of optically pure water which Spring was among the first to have prepared. Water devoid of Tyndall effects was obtained by carrying down the sedimented particles with the aid of colloidal precipitated zinc and aluminum hydroxide formed by the action of ammonia on soluble salts of zinc and aluminum. I n order to determine the color of pure water he observed layers as thick as 26 meters, which rxprrimentntion nrw4tated opticnl instnim~nts of extreme orccision rml rcouirrd skilful mminulwion. Spring determined that pure water is blue whereas running water is green or brown by virtue of particles of humic acid suspended in it. The color researches were extended to organic liquids, of which hydrocarbons were shown to have a yellow color and alcohols, interestingly enough, to be green-the color intermediate between water and the paraffins. Spring did much to help prove that gravitational, electrical, magnetic, and surface tension forces between particles were not the causes of Brownian motion,' a controversial subject in 1900 which was being debated vigorously among his contemporary investigators. On salt solutions it was observed that true solutions formed by the alkali metals salts were optically clear, whereas with salts of heavy metals hydrolysis produced hydrates of colloidal, light-scattering dimensions. In order to make these observations he devised and constructed an optical instrument which later became the ultramicroscope of Siedentopf and Zsigmondy. Finally, Spring discovered variations in properties such as color and conductivity in solutions of electrolytes, e. g., potassium bichromate, which varied with time. He interpreted these phenomena to be the result of a slow disaggregation of complexes formed by chromic acid in solutions. Numerous other labors can be listed among such varied fields as crystallography, pharmacy, organic chemistry, physics, and geography, including the publication of joint . uauers . with Ostwald and van% off. The published articles by waiter Spring number well over one hundred and include considerations of natural uhenomena such as the color of the skv. " , a hionraohv of jean Stas, and descriptive writing on the scenic beauties of the Mosan V a l l e ~ . ~ Biographical literature on Walter Spring is suggestive of an eccentricity characteristic of the type who, by secluded study, lives exclusively for his professed work and renounces all social contacts. Dr. Jean Timmermans (rather anomalously) says of Spring that he was a veritable misanthrope possessed of a warm heart. Nevertheless, his proclivity for broad, imaginative research in basic science and his dextrous ability in manipulative procedures have earned for Walter Spring the distinction of having been one of Belgium's most productive and original chemists. U
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