Coschwitz, was nothing more than a blood-vessel. Haller then visited London, making the acquaintance of Sir Hans Sloane, Cheselden, Pringle, Douglas, and other scientific men ; next, after a short stay in Oxford, he visited Paris, where he studied under Ledran and Winslow ; and in 1728 lie proceeded to Basel, where he devoted himself to the study of the higher mathematics under John Bernoulli. It was during his stay there also that his first great interest in botany was awakened ; and, in the course of a tour through Savoy, Baden, and several of the Swiss cantons, he began a collection of plants which was afterwards the basis of his great work on the flora of Switzerland. In 1729 he returned to Bern and began to practise as a physician ; his best energies, however, were devoted to the botanical and anatomical researches which rapidly gave him a European reputation, and procured for him from George II. in 1736 a call to the chair of medicine, anatomy, botany, and surgery, in the newly- founded university of Gottiugen. The quantity of work achieved by Haller in the seventeen years during which he occupied this post was immense. Apart from the ordinary work of his classes, which entailed upon him the task of newly organizing a botanical garden, an anatomical theatre and museum, an obstetrical school, and similar institutions, he carried on without interruption those original investigations in botany and physiology, the results of which are preserved in the numerous works asso ciated with his name; he continued also to persevere in his youthful habit of poetical composition, while at the same time he conducted a monthly scientific journal to which he is said to have contributed twelve thousand articles relating to almost every branch of human knowledge. He also warmly interested himself in most of the religious questions, both ephemeral and permanent, of his day ; and the erection of the Reformed church in Gottingen was mainly due to his unwearied energy. Notwithstanding all this variety of absorbing interests he never felt afc home in Gottingen ; his untravelled heart kept ever turning towards his native Bern (where he had been elected a member of the great council in 1745), and in 1753 he resolved to resign his chair and return to Switzerland. The twenty-one years of his life which followed were largely occupied in the dis charge of his duties as " amman," to which honourable office he had been chosen by his fellow-citizens, and in the preparation of his Bibliotheca Medica, the botanical, surgi cal, and anatomical parts of which he lived to complete ; but he also found time to write the three philosophical romances, Usong (1771), Alfred (1773), and Fabius and Cato (1774), in which his views as to the respective merits of despotism, of limited monarchy, and of aristocratic republi can government are fully set forth. About 1773 the state of his health rendered necessary his entire withdrawal from public business ; for some time he supported his failing strength by means of opium, on the use of which he com municated a paper to the Proceedings of the Gottingen Royal Society in 1776 ; the excessive use of the drug is believed, however, to havehastened his death, whichoccurred on the 17th of December 1777. Haller, who had been three times married, left eight children, the eldest of whom, Gottlieb Emanuel, attained to some distinction as a botanist
and as a writer on Swiss history.
For some account of Haller s contributions to the sciences of which he was especially an ornament, see the articles Anatomy (volumevol. i. p. 814) and Physiology. Subjoined is a classified but by no means an exhaustive list of his very numerous works in various branches of science and literature : (1) Anatomical :lcones ana- tomiccK (1743-54); Disputationcs anatomicce seUdiores (1746-52); and Opera acad. minora anatomici argumenti (1762-68). (2) Physiological: Dercspirationecxperimcntaanatomica(l7tf}-,Prim<K hnece physiologic (1747); and Elementa physiologice corporis humani (1757-60). (3) Pathological and surgical -.Opuscula patho- logica (1755); Disputationum chirurg. collcdio (1777); also careful editions of Boerhaave s Prxlectiones academics in proprias insti- tutiones rci mcdiccc (1739), and of the Arils medicos principles of the same author (1769-74). (4) Botanical : Enumeratio stirpium Hcl- veticarum (1742); Opuscula, botanica (1749); Bibliotheca botanica (1771). (5) Theological : Briefc ube-r die ivichtigsten Wahrheiten der Offenbarung (1772); and Brief e zur Verthcidigung der Offen- barung .(1775-77). (6) Poetical -.Gedichte (1732, 12th ed. 1777). His three romances have been already mentioned. Several volumes of lectures and " Tagebiicher " or journals were published post humously.
Sec J. G. Zinimermiinn, Das Leben des Ilerrn von Halltr (1755), and the aiticlcs by Forster and Seller in Ersch and Gruber s Kncyklopddie.
HALLEY, Edmund (1656–1742), an eminent astronomer, was born at Haggerston, near London, October 29, 1656. His father, a wealthy soapboiler, desiring to give his only son an education suitable to his promising genius, placed him at St Paul s School, where he was equally dis tinguished for classical as for mathematical ability. Before leaving it for Queen s College, Oxford, which he entered as commoner in 1673, he had observed the change in the variation of the compass, and, at the age of nineteen, he supplied a new and improved method of determining the elements of the planetary orbits. His detection of consider able errors in the tables then in use led him to the con clusion that a more accurate ascertainment of the places of the fixed stars was indispensable to the progress of astronomy ; and, finding that Flamsteed and Hevelius had already undertaken to catalogue those visible in northern latitudes, he assumed to himself the task of making observa tions in the southern hemisphere. A recommendation from Charles II. to the East India Company procured for him an apparently suitable, though, as it proved, ill-chosen station, and in November 1676 he embarked for St Helena. On the voyage he noticed the retardation of the pendulum in approaching the equator : and during his stay on the island he observed the transit of Mercury, which sug gested to him the important idea of employing similar phenomena for the calculation of the solar distance. He returned to England in November 1678, having by the registration of 360 stars won the title of the "Southern Tycho," and by the translation to the heavens of the " Royal Oak," earned a degree of master of arts, conferred at Oxford by the king s command December 3, 1678, almost simultaneously with his election as fellow of the Royal Society. Six months later, the indefatigable astro nomer started for Dantzic to set at rest a dispute of long standing between Hooke and Hevelius as to the respective merits of plain or telescopic sights ; and towards the end of 1680 he proceeded on a Continental tour. In Paris he observed with Cassini the great comet of 1680 after its perihelion passage ; and having returned to England, he married in 1682 Mary, daughter of Mr Tooke, auditor of the exchequer, with whom he lived harmoniously for fifty- five years. He now fixed his residence at Islington, engaged chiefly upon lunar observations, with a view to the great desideratum of a method of finding the longitude at sea. His mind, however, was also busy with the momentous pro blem of gravity. Having reached so far as to perceive that the central force of the solar system must decrease inversely as the square of the distance, and applied vainly to Wren and Hooke for further elucidation, he made in August 1684 that journey to Cambridge for the purpose of consulting Newton, which resulted in the publication of the Principia. The labour and expense of passing this great work through the press devolved upon Halley, who also wrote the prefixed hexameters ending with the well-known line—
Nee fas est propius mortali attingere divos.
troller of the mint at Chester, and (August 19, 1698) he received a commission as captain of the " Paramour Pink" for the purpose of making extensive observations on the conditions of terrestrial magnetism. This task he accom
plished in a voyage which lasted two years, and extended
