626 E W O H industries, which are largely manufacturing, are connected chiefly with the tanning of leather and the making of boots and shoes. Woburn is one of the older towns of Massachusetts, having been settled in 1642. Its growth, however, was slow, and it is only in recent years that it has attained to importance. WOELFL, JOSEPH (1772-1812), pianist and composer, was born in 1772 at Salzburg, where he studied music under Leopold Mozart and Michael Haydn. After a short residence at Warsaw he produced his first opera, Der Hollenbertj, with some success at Vienna, where it was soon followed by Das schone Milchmadchen and some other dramatic pieces. These, however, have been long for gotten, and his fame now rests upon his compositions for the pianoforte, and the skill with which he is said to have met their formidable demands upon his power as an executant. The perfection of his technique was im measurably enhanced by the enormous stretch of his fingers; and to the wide grasp of the key-board this placed at his command he owed a facility of execution which he turned to excellent account, especially in his extempore perform ances. So remarkable were these that even the youthful Beethoven did not disdain to play in company with him at the house of Count Wetzlar, and in memory of this exhibi tion of good-humoured rivalry he dedicated to Beethoven his Three Sonatas, Op. 6. Quitting Vienna in 1798 Woelfl exhibited his skill in most of the great European capitals, and, after spending some years in Paris, made his first appearance in London, May 27, 1805. Here he enjoyed a long term of popularity, crowned about 1808 by the publication of his Sonata, Op. 41, containing some variations on "Life let us cherish." This, on account of its technical difficulty, he entitled Non Plus Ultra ; and, in reply to the challenge, Dussek s London publishers reprinted a sonata by that composer, originally called Le Retoiir a Paris, with the title Phis Ultra, and an ironical dedication to Non Plus Ultra, Woelfl died in Great Marylebone Street, London, May 21, 1812. Some stories once current concerning his ruin by a card-sharper and death upon a heap of straw are proved to have been utterly without foundation. WOHLER, FRIEDRICH (1800-1882), chemist, was born on July 31, 1800, in Eschersheim, near Frankfort-on-the Main. While attending the village school of Rbdelheim, he received valuable additional instruction from his father, a man of more than ordinary acquirements. In 1812 the family removed to Frankfort, where he entered the gym nasium, and by the kindness of a scientific friend, Dr Buch, was introduced to the study of mineralogy, chemistry, and physics. He afterwards studied medicine at Marburg and Heidelberg, graduating in that faculty at the latter university. Having, on the advice of Leopold Gmelin, decided upon devoting himself henceforth to chemistry, he completed his chemical education at Stock holm, under Berzelius, in whose laboratory he worked for a considerable time, and with whom, during his subsequent life, he maintained the most friendly relations. While in Sweden he took part in a scientific expedition through Norway, which made him acquainted with the brothers Brongniart and with Humphrey Davy. After his return from Sweden in 1825, he accepted a call to Berlin as teacher of chemistry in the then newly- erected " gewerbschule," and remained there until 1832, when family affairs caused him to take up his abode in Cassel. In 1836 Wb hler became professor of chemistry in the medical faculty of the university of Gottingen, which office, in his case, was combined with that of inspector-general of pharmacy for Hanover. He held his chair till his death, which occurred, after a short illness, on the 23rd September 1882. Wbhler s career as a chemist extends over two generations. Some sixty years ago, when the elementary nature of chlorine had just been established, and the isolation of cyanogen was still a novelty, young Wb hler already worked as an investigator, the same Wbhler who rejoiced with the chemists of to-day over the synthesis of indigo. Of the world of chemical discoveries that lie between he magnet, pars fuit. Within the limits of the present article, however, it is impossible to do more than indicate briefly the nature of some of his greater achievements. Amongst these his discovery of cyanic acid, and what it led him to, occupy a prominent place. From these investigations of his the science of organic chemistry may be said to date. When, in 1828, Wbhler prepared the ammonia salt of his acid, he was astonished to find that the salt, although made by what appeared to be a straightforward double decomposition, did not exhibit the character of an ammonia salt at all, but turned out to lie identical with urea, a substance which heretofore had been known only as one of the organic components of urine. Prior to this discovery a wide and impassable gulf had in the minds of chemists separated the mineral from the organic kingdom. Inorganic bodies all appeared to be derivable from their elements by a succession of acts of binary combination ; the full analysis of such a body contained in itself the full instruction for its synthetical production in the laboratory. Organic substances, on the other hand, were supposed to be things of an entirely different order; in them the few elements which they all consist of were assumed to be united with one another, each with each, in a mysterious manner, which could be brought about only by the agency of vital force." Vital force, it was now seen, had nothing to do with the formation of urea at any rate. The gulf was bridged over, and a great and new morning full of the highest promise dawned over chemistry. If the promise was more than fulfilled, if organic chemistry from a mere possibility developed into a reality, we owe this chiefly to the great researches which were carried out con jointly by AVbhler and Liebig. One of the first, if not the first, of these was an investigation on the oxygenated acids of cyanogen, which they published in 1830. In their research they proved, both analytically and synthetically, that cyanic and cyanuric acid, although distinct bodies, have the same elementary composition, and that the former, when simply kept in a sealed-up tube, gradually passes wholly into a porcelain- like neutral solid, cyamelide, which is widely different from either. By these discoveries, and by Wbhler s synthesis of urea, the fact of isomerism was firmly established. Compared with this great conquest their joint work on mellitic acid (1830) and on sulpho- vinic acid (1831) appears small ; it sinks into insignificance when viewed in the light of their immortal researches on bitter-almond oil and on uric acid. In 1832 bitter-almond oil was supposed to be to bitter almonds what a hundred and one other essential oils are to their vegetable sources. Of its chemistry nothing was known except the fact that it contains loosely combined prussic acid, and that, when kept for a long time, it is liable to deposit a crystalline solid, as various other essential oils do. Liebig and Wbhler, being struck by the absence from even powdered bitter almonds of the intense smell characteristic of the oil, set about tracing the latter to its origin, and soon solved the question. In 1830 Robiquet and Boutron- Charlard had succeeded in extracting from bitter almonds a crystal line nitrogenous solid, soluble without decomposition in alcohol and in water, wluch they called amygdaline. What Liebig and Wbhler found was that, when bitter-almond meal is mashed up with water, this amygdaline, by the action of the water and a ferment (common to both sweet and bitter almonds), breaks up into sugar, prussic acid, and bitter-almond oil. They also succeeded in separating the prussic acid from the distilled oil, and found the thus purified oil to be a non-poisonous liquid of the composition C 7 H (i O. This liquid, when exposed to the air, readily takes up oxygen and assumes the form of a solid, which is identical at the same time with the quasi-stearoptene of the oil and with Scheele s benzoic acid, C 7 H G 2 . When treated with chlorine, the purified oil yields a chloride, CyHgO.Cl, the chlorine of which, by treatment with the respective potassium compounds, is displaced by its equivalent in bromine, iodine, sulphur, cyanogen, and, on treat ment with ammonia, by the group NH 3 . Water converts it into hydrochloric and benzoic acids. In all these reactions the group C 7 H 5 holds together; it moves forwards and backwards as if it were a compound element, a common-place enough fact in the eyes of the chemical student of 1882, but a most wonderful revelation to the chemist of 1832. Berzelius, who certainly was not much given to dealing in superlatives, greeted the discovery in his Jahresbericht as opening up a new era in organic chemistry, and, rejecting the prosaic name of benzoyl which Wbhler and Liebig had given to their radical, proposed to name it proine, from irpw t, early in the day, or orthrine, from upOpos, the dawn. Equally important in a scientific sense, but greater as a piece of experimental work, was their joint research on URIC ACID (q.v.).
After their uric acid research the ways of Wbhler and Liebig