1911 Encyclopædia Britannica/Hofmann, August Wilhelm von
HOFMANN, AUGUST WILHELM VON (1818-1892), German chemist, was born at Giessen on the 8th of April 1818. Not intending originally to devote himself to physical science, he first took up the study of law and philology at Göttingen, and the general culture he thus gained stood him in good stead when he turned to chemistry, the study of which he began under Liebig. When, in 1845, a school of practical chemistry was started in London, under the style of the Royal College of Chemistry, Hofmann, largely through the influence of the Prince Consort, was appointed its first director. It was with some natural hesitation that he, then a Privatdozent at Bonn, accepted the position, which may well have seemed rather a precarious one; but the difficulty was removed by his appointment as extraordinary professor at Bonn, with leave of absence for two years, so that he could resume his career in Germany if his English one proved unsatisfactory. Fortunately the college was more or less successful, owing largely to his enthusiasm and energy, and many of the men who were trained there subsequently made their mark in chemical history. But in 1864 he returned to Bonn, and in the succeeding year he was selected to succeed E. Mitscherlich as professor of chemistry and director of the laboratory in Berlin University. In leaving England, of which he used to speak as his adopted country, Hofmann was probably influenced by a combination of causes. The public support extended to the college of chemistry had been dwindling for some years, and before he left it had ceased to have an independent existence and had been absorbed into the School of Mines. This event he must have looked upon as a curtailment of its possibilities of usefulness. But, in addition, there is only too much reason to suppose that he was disappointed at the general apathy with which his science was regarded in England. No man ever realized more fully than he how entirely dependent on the advance of scientific knowledge is the continuation of a country's material prosperity, and no single chemist ever exercised a greater or more direct influence upon industrial development. In England, however, people cared for none of these things, and were blind to the commercial potentialities of scientific research. The college to which Hofmann devoted nearly twenty of the best years of his life was starved; the coal-tar industry, which was really brought into existence by his work and that of his pupils under his direction at that college, and which with a little intelligent forethought might have been retained in England, was allowed to slip into the hands of Germany, where it is now worth millions of pounds annually; and Hofmann himself was compelled to return to his native land to find due appreciation as one of the foremost chemists of his time. The rest of his life was spent in Berlin, and there he died on the 5th of May 1892. That city possesses a permanent memorial to his name in Hofmann House, the home of the German Chemical Society (of which he was the founder), which was formally opened in 1900, appropriately enough with an account of that great triumph of German chemical enterprise, the industrial manufacture of synthetical indigo.
Hofmann's work covered a wide range of organic chemistry, though with inorganic bodies he did but little. His first research, carried out in Liebig's laboratory at Giessen, was on coal-tar, and his investigation of the organic bases in coal-gas naphtha established the nature of aniline. This substance he used to refer to as his first love, and it was a love to which he remained faithful throughout his life. His perception of the analogy between it and ammonia led to his famous work on the amines and ammonium bases and the allied organic phosphorus compounds, while his researches on rosaniline, which he first prepared in 1858, formed the first of a series of investigations on colouring matters which only ended with quinoline red in 1887. But in addition to these and numberless other investigations for which he was responsible the influence he exercised through his pupils must also be taken into account. As a teacher, besides the power of accurately gauging the character and capabilities of those who studied under him, he had the faculty of infecting them with his own enthusiasm, and thus of stimulating them to put forward their best efforts. In the lecture-room he laid great stress on the importance of experimental demonstrations, paying particular attention to their selection and arrangement, though, since he himself was a somewhat clumsy manipulator, their actual exhibition was generally entrusted to his assistants. He was the possessor of a clear and graceful, if somewhat florid, style, which showed to special advantage in his numerous obituary notices or encomiums (collected and published in three volumes Zur Erinnerung an vorangegangene Freunde, 1888). He also excelled as a speaker, particularly at gatherings of an international character, for in addition to his native German he could speak English, French and Italian with fluency.