FORBES, David (1828-1876), F.RS., an accomplished traveller, mineralogist, metallurgist, chemist, and writer on chemical geology, brother of Professor Edward Forbes, was born at Douglas, Isle of Man, and received his early education there and at Brentwood in Essex. When a boy he manifested “an enthusiastic disposition as regards science,” and at the age of fourteen had already acquired a remarkable knowledge of chemistry. This subject he studied at the university of Edinburgh, and he was still young when he was appointed superintendent of the mining and metallurgical works at Espedal in Norway. Subsequently he became a partner in the firm of Evans & Aiken, nickel-smelters, of Birmingham, and in that capacity visited Chili, Bolivia, and Peru. He died in London, December 5, 1876. Micro-petrology and chemical geology owe much to the researches of David Forbes. Besides reports for the Iron and Steel Institute, of which, during the last years of his life, he was foreign secretary, lie wrote upwards of 50 papers on scientific subjects, among which are the following :—“The Action of Sulphurets on Metallic Silicates at High Temperatures,” Rep. Brit. Assoc., 1855, pt. ii. p. 62; “The Relations of the Silurian and Metamorphic Rocks of the south of Norway,” Lb., p. 82; “The Causes producing Foliation in Rocks,” Journ. Geol. Soc., xi., 1855; “The Chemical Composition of the Silurian and Cambrian Limestones,” Phil. Mag., xiii. pp. 365-373, 1857; “The Geology of Bolivia and Southern Peru,” Journ. Geol. Soc., xvii. pp. 7-62, 1861.

FORBES, Duncan (1685-1747), of Culloden, was born at Bunchrew or at Culloden near Inverness on the 10th of November, 1685. After he had completed his studies at the universities of Edinburgh and Leyden, he was admitted advocate at the Scottish bar in 1709. His own talents and the influence of the Argyll family secured his rapid advancement, which was still further helped by his loyalty to the Hanoverian cause at the period of the rebellion in 1715. In 1722 Forbes was returned member for Inverness, and in 1725 he succeeded Dundas of Arniston as lord advocate. He inherited the patrimonial estates on the death of his brother in 1734, and in 1737 he attained to the highest legal honours in Scotland, being made lord president of the Court of Session. As lord advocate, he had laboured to improve the legislation and revenue of the country, to extend trade and encourage manufactures, and no less to render the Government popular and respected in Scotland. In the proceedings which followed the memorable Porteous mob, for example, when the Government brought in a bill for disgracing the lord provost of Edinburgh, for fining the corporation, and for abolishing the town-guard and city-gate, Forbes both spoke and voted against the measure as an unwarranted outrage on the national feeling. As lord president also he carried out some useful legal reforms; and his term of office was characterized by quick and impartial administration of the law. The rebellion of 1745 found him at his post, and it tried all his patriotism. For some years before, he had repeatedly and earnestly urged upon the Government the expediency of embodying Highland regiments, putting them under the command of colonels whose loyalty could be relied upon, but officering them with the native chieftains and cadets of old families in the north. “If Government,” said he, “pre-engages the Highlanders in the manner I propose, they will not only serve well against the enemy abroad, but will be hostages for the good behaviour of their relations at home; and I am persuaded that it will be absolutely impossible to raise a rebellion in the Highlands.” Such a plan was afterwards successfully pursued by Chatham; but, though Walpole is said to have approved of the scheme, it was not adopted by the council. On the first rumour of the Jacobite rising Forbes hastened to Inverness, and through his personal influence with the chiefs of Macdonald and Macleod, those two powerful western clans were prevented from taking the field for Charles Edward; the town itself also he kept loyal and well protected at the commencement of the struggle, and many of the neighbouring proprietors were won over by his persuasions. His correspondence with Lord Lovat, published in the Culloden papers, affords a fine illustration of his character, in which the firmness of loyal principle and duty is found blended with neighbourly kindness and consideration. But at this critical juncture of affairs, the apathy of the Government interfered considerably with the success of his negotiations. Advances of arms and money arrived too late, and though Forbes employed all his own means and what money he could borrow on his personal security, his resources were quite inadequate to the emergency. It is doubtful whether these advances were ever fully repaid. Part was doled out to him, after repeated solicitations that his credit might be maintained in the country; but it is evident he had fallen into disgrace in consequence of his humane exertions to mitigate the impolitic severities inflicted upon his countrymen after their disastrous defeat at Culloden. The ingratitude of the Government, and the many distressing circumstances connected with the insurrection, sunk deep into the mind of Forbes. He never fairly rallied from the depression thus caused, and after a period of declining health he died on the 10th of December 1747, in the sixty-third year of his age.

Forbes was a patriot without ostentation or pretence, a true Scotsman with no narrow prejudice, an accomplished and even erudite scholar without pedantry, a man of genuine piety without asceticism or intolerance. His country long felt his influence through her reviving arts and. institutions; and the example of such a character in that coarse and venal age, and among a people distracted by faction, political strife, and national antipathies, while it was invaluable to his contemporaries in a man of high position, is entitled to the lasting gratitude and veneration of his countrymen. In his intervals of leisure he cultivated with some success the study ot philosophy, theology, and biblical criticism. He is said to have been a diligent reader of the Hebrew Bible. His published writings, some of them of importance, include— A Letter to a Bishop, concerning some Important Discoveries in Philosophy and Theology (1732); Some Thoughts concerning Religion, natural and revealed, and the Manner of Understanding Revelation (1735); and Reflections on Incredulity (2d ed. 1750). His correspondence was collected and published in 1815, and a memoir of him (from the family papers) was written by Mr Hill Burton, and published along with a Life of Lord Loι∙at, in 1847. His statue by Roubiliac stands in the Parliament House, Edinburgh.

FORBES, Edward (1815-54), F.R.S., a celebrated naturalist, was born at Douglas, in the Isle of Man, February 12, 1815. While still a child, when not engaged in reading, or in the writing of verses and drawing of caricatures—ever favourite recreations with him—he occupied himself with the collecting and arranging of insects, shells, minerals, fossils, specimens of plants, and other natural history objects. From his fifth to his eleventh year, delicacy of health precluded his attendance at any school, but in 1828 he became a day scholar at Athole House Academy in Douglas, where he was universally beloved by his companions, and was recognized by his master as an apt if not a good scholar. In June 1831 he left the Isle of Man for London, where during four months he studied drawing under Mr Sass, a well-known artist. In October, however, having given up all idea of making painting his profession, he returned home; and in the following month he matriculated as a student of medicine in the university of Edinburgh. During his first winter session there he attended lectures on anatomy, theoretical chemistry, and materia medica; and in the ensuing summer session botany, natural history, and practical chemistry claimed his attention. His vacation in 1832 he spent in diligent work on the natural history of the Isle of Man. In 1833 he made a tour in Norway, the botanical results of which were published in Loudon’s Magazine of Natural History for 1835-36. In the summer of 1834 he visited the Isle of Man and Wales, and devoted much time to dredging in the Irish Sea; and in the succeeding year he travelled in France, Switzerland, and Germany. Born a naturalist, and having no relish for the practical duties of the surgeon or physician, Forbes was no zealous student of medicine, and he finally in the spring of 1836 abandoned the idea of taking a medical degree, resolving to devote himself to science and literature. The winter of 1836-37 found him at Paris, where he attended the lectures at the Jardin des Plantes on natural history, comparative anatomy, geology, and mineralogy. Leaving Paris in April 1837, he repaired to the south of France, whence he*· went to Algiers, and during a month there spent he obtained materials for a paper on land and freshwater Mollusca, published in the Annals of Natural History, vol. ii. p. 250. In the autumn of the same year he registered at Edinburgh as a student of literature; and in 1838 appeared his first volume, Malacologia Monensis, a synopsis of the species of Manx Mollusca. During the summer of 1838 he visited Styria and Carniola, and made extensive botanical collections. In the following autumn he read before the British Association at Newcastle a paper on the distribution of terrestrial Pulmonifera in Europe, and was commissioned to prepare a similar report with reference to the British Isles. On returning to Edinburgh he delivered a course of 15 lectures on the natural history of the animals in the British seas. In 1841 was completed the publication of Forbes’s great work, A History of British Star-fishes, embodying the results of researches carried on for a long series of years, and containing 120 illustrations, inclusive of humorous tailpieces, all designed by the author. On April 17th of the same year Forbes, accompanied by his friend William Thompson, joined at MaltaH.M. surveying ship “Beacon,” to which he had been appointed naturalist by her commander Captain Graves. From that date until October 1842 he was busily employed in investigating the botany, zoology, and geology of the Mediterranean region. The results of his researches were made known in his “Report on the Mollusca and Radiata of the Aegean Sea, presented to the British Association in 1843,” and in Travels in Lycia, published in conjunction with Lieut. Spratt in 1846. In the former treatise he discussed the influence of climate and of the nature and depth of the sea bottom upon marine life, and divided the AEgean into eight biological zones; his conclusions with respect to bathymetrical distribution, however, have been shown by later investigators to require certain considerable modifications. Towards the end of the year 1842 Forbes, whom family misfortunes had now thrown upon his own resources for a means of livelihood, sought and obtained the curatorship of the collections of the Geological Society of London. To the duties of that post he, in May of the following year, added those of the professorship of botany at King’s College, where he lectured with success to the second largest botanical class in London. On November 1, 1844, having resigned the curatorship of the Geological Society, he became palaeontologist to the Geological Survey, with a yearly salary of £300. In 1846 Forbes published in the Memoirs of the Geological Survey, i. 336, his important treatise “On the Connexion between the existing Fauna and Flora of the British Isles, and the Geographical Changes which have affected their Area.” It is therein pointed out that, in accordance with the theory of their origin from various specific centres, the plants of Great Britain may be divided into five well-marked groups :—the W. and S.W. Irish, represented in the N. of Spain; the S.E. Irish and S.W. English, related to the flora of the Channel Isles and the neighbouring part of France; the S.E. English, characterized by species occurring on the opposite French coast; a group peculiar to mountain summits, Scandinavian in type; and, lastly, a general or Germanic flora. From a variety of arguments the conclusion is drawn that the greater part of the terrestrial animals and flowering plants of the British Islands migrated thitherward, over continuous land, at three distinct periods, before, during, and after the glacial epoch. In the autumn of 1848 Forbes married the daughter of General Sir C. Ashworth. The year 1851 witnessed the removal of the collections of the Geological Survey from Craig’s Court to the new museum in Jermyn Street, and the appointment of Forbes as professor of natural history to the Royal School of Mines just established in conjunction therewith. In 1852 was published the fourth and concluding volume of Forbes and Hanley’s History of British Mollusca. In 1853 Forbes held the presidency of the Geological Society of London, and in the following year he obtained the fulfilment of a long-cherished wish in his appointment to the professorship of natural history in the university of Edinburgh, vacant by the death of Jameson, his former teacher. Since his return from the East in 1842, the determination and arrangement of fossils, the investigation of strata, frequent lectures, and incessant and wearing literary work, including the preparation of his admirable palaeontological memoirs, and of a variety of scientific articles and reviews, had precluded Forbes from giving that attention to the natural history pursuits of his earlier life which he had for years earnestly desired. It seemed that at length he was to find leisure to reduce to order and commit to the keeping of the press those vast stores of biological information of which long protracted and original research had made him the possessor. At Edinburgh, in the summer session of 1854, he lectured to a large and appreciative audience; and in September of that year he occupied the post of president of the geological section at the meeting of the British Association. He had already commenced his winter’s course of lectures in Edinburgh when he was seized with feverishness, culminating in an attack of nephritic disease, from which he had on several previous occasions been a sufferer. His symptoms soon became alarming, and after not many days’ illness he expired at Wardie, near Edinburgh, Nov. 18, 1854, in the fortieth year of his age.

See Literary Gazette, November 25, 1854; Edinburgh New Philosophical Journal (NewSer.), 1855; Quart. Joum. Geol. Soc., May 1855; G. Wilson and A. Geikie, Memoir of Edward Forbes, 1861, in which, pp. 575-583, is given a list of Forbes’s writings. See also the Royal Society’s Catalogue of Scientific Papers, vol. ii. pp. 654- 658.

FORBES, James David (1809-1868), successively professor of natural philosophy in the university of Edinburgh and principal of the United College in the university of St Andrews, was the fourth son of Sir William Forbes of Pitsligo, the lineal representative of the Forbeses of Monymusk and Pitsligo. His mother was Wilhelmina Belches-Stuart, sole child and heiress of Sir John Stuart of Fettercairn. Their family consisted of two daughters and four sons, of whom James David, born at his father’s town house, 86 George Street, Edinburgh, on the 20th April, 1809, was the youngest. Two years after his birth, the death of Lady Forbes took place., Sir William retired with his family from Edinburgh to Colinton, his country residence, and thus it happened that, up to the age of sixteen, when he entered college, James Forbes was entirely a home-bred boy, and his only teacher the schoolmaster of the village. At an early age, however, he developed remarkable powers of self-education. Passionately fond of natural science, he stored his mind with all available knowledge of physics, constructed for himself astronomical instruments, and actually commenced a connected series of meteorological observations, which he kept up for many years. But these pursuits were carried on without the knowledge of his family; for Sir William had destined him for the bar, and Forbes loved his father too well to betray tastes and inclinations which might seem to point towards a different career. In November 1825 he entered the university of Edinburgh, and joined the classes of Latin and chemistry. He still continued his self-imposed studies, and at length forwarded anonymously to Sir David (then Dr) Brewster, who was at the time conducting the Edinburgh Pldlosophical Journal, a paper on “The Apparent Number of the Stars.” It was at once inserted, and further communications were requested from the anonymous “A.” The request was complied with, and during an extended tour through France, Germany, and Italy, in company with a large family party, Forbes contributed a number of papers on “The Physical Geography of the Bay of Naples,” “The Horary Oscillations of the Barometer at Rome,” and other subjects, all of which were inserted in the Journal. On his return to Scotland after a year’s absence, he made himself known to Brewster as his unknown correspondent. Brewster, astonished at his extensive reading and remarkable powers of observation, encouraged him in his scientific pursuits, and proposed him as a fellow of the" Royal Society of Edinburgh, to which, at the age of 19, he was elected. In the meantime he had re-entered college, where his subsequent career was a distinguished one. In the class of moral philosophy, taught by the celebrated Professor Wilson, he gained the highest honours, and in Sir John Leslie’s natural philosophy class he twice carried off the gold medal. An event now occurred which changed the whole tenor of his life. His father died on the 24th of October 1828, and it became necessary that Forbes should seriously consider his future course of life. The choice lay between the bar and a scientific career, and after much consultation with his friends he chose the latter. He passed his law trials indeed, and put on his advocate’s gowu, but never wore it, for a competence given him by his father had rendered him independent. About this time Sir David Brewster was engaged in laying the foundations of the British Association. Forbes joined cordially in the work, and contributed much towards placing the Association on the basis it now occupies. Throughout the rest of his life he attended, with rare exceptions, all its meetings, often breaking off a foreign tour, and hastening back to do so. The presidency of the meeting held at Dundee in 1867 was offered to him, but ill health compelled him to decline it

Immediately after his election as fellow of the Royal Society of London, in June 1832, Forbes started on an extensive scientific tour, but was suddenly recalled from Geneva by news of the death of Sir John Leslie, professor of natural philosophy at the university of Edinburgh. Forbes had left word that should this chair at any time become vacant, he desired to be put in nomination, and on his return found that this had actually been done. He also found himself, to his surprise and dismay, the rival of his old friend Sir David Brewster. But Forbes was already committed, and had received testimonials from Whewell, Airy, Peacock, Vernon Harcourt, Chalmers, and others, bearing high testimony to his attainments, and the immense results they promised. After a more than usually excited contest, into which politics to some extent entered, Forbes was elected, at the age of twenty-four, to a professorial chair of the highest distinction. The inaugural lecture with which he opened the session of 1833-34 was listened to with unusual interest. As a professor, he more than realized the high expectations which had been formed of his special capacity for the work. During the twentyseven years of his professorship his lectures left no branch of natural philosophy untouched, and owing to his thorough acquaintance with the literature of the subject, each of them was a mass of condensed information,—not, however, confined to old knowledge taken from books, but enriched from time to time by the results of original research, enlivened by many a happy illustration drawn from his travels and adventures, and rendered more effective by his clear ringing voice and graceful delivery. He soon gathered round him an enthusiastic body of hard-working students, and although the high standard he aimed at made him a somewhat strict disciplinarian, their personal interest in his researches and their pride in his success increased as years went on. Forbes took an interest in his students no less personal, and more than one acquaintance formed in the class-room ripened into a tender and affectionate friendship. But his energies were not confined to the work of his professorship; they soon made themselves felt throughout all the machinery of the university. The system of examination for degrees—already for some time in operation at Oxford—was then much wanted at Edinburgh, where, owing to the absence of any sufficient test of proficiency, graduation was little valued and seldom sought for. Forbes became an energetic reformer in this direction, and to him is mainly owing the complete system of examination for degrees which, under his guidance as dean of the faculty of arts, greatly tended to raise the standard of Scottish education. Again, in 1841, there was much discussion in the senatus as to the disposal of a large sum of money bequeathed by General Reid for the foundation of a chair of music and for other purposes.

Forbes strongly opposed the idea of a musical professorship, urging that the money would be more usefully employed in providing retiring allowances for superannuated professors. But controversy ran high, litigation ensued, and after years of contention a part of the Reid bequest was assigned by the law courts to the chair of music. Next year another large sum, the Straton fund, had to be dealt with, and here again Forbes was instrumental in inducing the senate to devote what was left of the Reid bequest, combined with the Straton fund, to the foundation of fellowships to be held by distinguished students after graduation. In these and other controversies the uncompromising energy with which he strove to carry out his views of what was right could not fail to bring him into collision with men whose opinions were as decided, and their wills as strong as his own. When two such unbending natures as Sir William Hamilton and James Forbes came into contact—as they did more than once—the shock was a rough one; but although they differed widely in opinions, each has left a permanent mark for good on the university.

It would be impossible to enter here into the subjects or method of Forbes’s class lectures; nor is it necessary to give more than a brief notice of the important researches which shared with his class work the winter mouths. They were the subject of voluminous private correspondence with such men as Whewell, Brewster, Peacock, Airy, Faraday, Arago, Melloni, Cauchy, and many others, and their results were embodied in a long list of communications to various scientific societies, ranging over a great variety of subjects.

For a paper on “The Transparency of the Atmosphere and the Laws of Extinction of the Sun’s Rays passing through it,” the Royal Society of London awarded him their Royal Medal. Another, on “The Selective Absorption of the Sun’s Light in passing through Steam,” was one of the first steps in the direction of spectrum analysis. In 1832 he described the experiments by which he succeeded in producing a spark by means of a natural magnet. He was the author of valuable memoirs on the thermal springs of the Pyrenees, the extinct volcanoes of the Vivarais (Ardêche), and the geology of the Cuchullin and Eildon hills. Soon after his elevation to the chair Forbes resumed his researches in heat, begun some years before. He commenced experiments with Melloni’s thermo-multiplier, measured the refractive index of rock salt with heat from various sources, luminous and non-luminous, and pursued a course of investigations which led him to his most brilliant discovery, the polarization of non-luminous heat, by transmission through tourmaline and thin mica plates, and by reflection from the latter. By employing mica for depolarization he succeeded in showing the double refraction of non-luminous heat, a fact of which this experiment remains the only proof. He also produced circularly polarized heat by two internal reflections, using Fresnel’s rhombs made of rock salt. By these researches the identity of thermal and luminous radiations was finally established. In 1846 he made careful arrangements for the measurement of underground temperatures, and by sinking his thermometers in three different sets of surface materials, he obtained an absolute determination of the thermal conductivity of traptufa, sandstone, and pure loose sand. His experiments on the conductivity of metals occupied the closing years of his life. By a thoroughly original method he obtained quantitative measurements of the absolute thermal conductivity of iron at various temperatures, and showed that this is diminished (contrary to the assumption of Fourier) by increase of temperature, thus following the known laws of electrical conductivity.

Forbes generally devoted a part of each vacation to excursions with his family in various parts of Scotland, and to geological tours among his native mountains, in the course of which, at times in company with some scientific friend, more often alone, he traversed on foot the greater part of the Highlands. In 1856 he acquired a beautiful cottage near Pitlochrie in Perthshire, where the succeeding summers were chiefly spent. From 1835 to 1851 Forbes usually passed some months on the Continent, travelling, as he expressed it, not as an amusement, but as a serious occupation, with De Saussure before him as a model And it may be almost doubted whether science did not profit as much by his summer travels as by his winter work.

His first tour was devoted to the geology of the Pyrenees and of the Vivarais—the latter of which be afterwards revisited. In 1837, after a short sojourn at Bonn, for the purpose of study, he travelled throughout Germany and Austria, making frequent experiments on terrestrial magnetism and other subjects. In 1839, among the crags and glaciers of Monte Viso, of the Pelvoux range, and of the Alps of Cogne, he learned to be an active and intrepid mountaineer; and during the intervals of his glacier investigations he did good service in opening up Alpine districts before scarcely known to Englishmen, by a series of excursions extending over the whole of the Pennine chain.

But of all his journeys and discoveries, those made by him among the mountains of Savoy are most popularly known; and their results have associated his name for ever with the glaciers of the Alps. In 1840, while presiding over the physical section of the British Association at Glasgow, he met Μ. Agassiz of Neuchâtel—who, after spending several years in the study of glacial phenomena, had just published his2‰awA⅛ sur les Glaciers,— and agreed to visit Switzerland with him the following year. Accordingly, at the close of the session of 1840-41, Forbes joined Agassiz and his party at the well-known “Hôtel des Neu-châtelois,” a small hut on the moraine of the Lauter Aar Gletscher. After a fortnight spent in exploration and observation, in the course of which Forbes called attention for the first time to the veined structure of glacier ice, they ended the campaign by the passage of the Ober Aar Joch, and the ascent of the Jungfrau. This was Forbes’s apprenticeship in glacier observation,—a field of inquiry then jointly occupied by two rival theories, the gravitation or sliding theory of De Saussure, and the dilatation theory of Charpentier. After a close analysis of these Forbes not only showed conclusive physical reasons for rejecting both, but pointed out the impossibility of forming a sound theory of glaciers until the internal structure of these anomalous bodies had been investigated, and the character and velocity of their motions ascertained.

These important data Forbes resolved to obtain for himself, and the summer of 1841 found him at Chamounix, engaged in a close examination of the Μ er de Glace. He attacked the problem for the first time as a question of pure physics, executed accurate measurements with instruments of precision, -and at once established the fact that the motion of a glacier averages roughly a foot in 24 hours, and that such motion is continuous. As his observations went on, he successively discovered that the centre of the glacier moves faster than the sides, and the surface than the ice vertically below it, that its velocity increases directly with the steepness of its bed, and that the motion of a portion of the glacier when embayed behind a rock is greatly diminished, and the whole mass distorted, without any solution of continuity taking place. Convinced by these discoveries that the resemblance between a glacier and a river, already noticed by Captain Hall, Msgr. Rendu, and others, was more than a mere analogy, he deduced from the above mentioned data the following theory of glacier motion :— A glacier is an imperfect fluid or a viscous body, which is urged down slopes of a certain inclination by the mutual pressure of its parts. In reply to the strongly urged objection that ice is by its nature a brittle solid, and not sensibly possessed of any viscous quality, he asserted that ice is only hard and crystalline at a temperature of 30° F. or lower, and that at 32° it is a plastic solid possessing a slight but perfectly sensible genuine molecular plasticity. When the urgency of the forces to which it is subjected causes this limit to be overpowered, a general bruise takes place, producing innumerable internal fissures, with finite displacements in certain planes, and subsequent restoration of continuity by “time and cohesion”; hence the blue bands of the conchoidal veined structure. When the urgency is still greater the mass acts like a solid, and crevasses open. In the case of glacier ice an additional element of plasticity exists, for glacier ice is scarcely ever coherent. It is usually a congeries of irregular polyhedrons tightly wedged together, possessing a rude flexibility, and always traversed by an infinity of capillary fissures. Hence a glacier is really a compound of ice and water, more or less plastic according to its wetness and infiltration,—a fact proved by its more rapid motion in summer when saturated with water, and its relative retardation in winter when the surface water remains frozen. Forbes’s “viscous theory” was sharply criticized, but it is now universally accepted, subject to some modifications which do not affect the groundwork of the structure, and rather elucidate than disprove his conclusions. But besides scientific criticism, he was compelled to defend himself—which he did with complete success—against insinuations, not only of plagiarism, but of an endeavour to suppress the rights of others to priority of discovery.

During the winter which followed this eventful summer, Forbes was busily engaged in writing his Travels through the Alps of Savoy, a charming contribution to Alpine literature, in which graphic descriptions of scenery and mountaineering are happily blended with accounts of his scientific researches. Its last lines were written almost on the eve of his marriage with Alicia, eldest daughter of the late George Wauchope, Esq. They started on their marriage tour to Switzerland, but had only got so far as Bonn, when Forbes was attacked by a dangerous illness, and it was not until August that they reached the Alps. He was then so far restored as to be able to resume his observations on the glaciers of Chamounix and Grindelwald, but as the winter approached he was pronounced unequal to the work of the following session at Edinburgh. His request for permission to appoint a substitute was readily granted, and he set out with Mrs Forbes for Italy. Naples and Rome were their headquarters until the end of May, and the summer months were passed at the Italian lakes and in Switzerland. Forbes returned to Edinburgh in the autumn of 1844, and carried on his work during the winter months, but his health had suffered a rude shock, from the effects of which he never entirely recovered, The succeeding summer was spent with his family in the Highlands of Scotland; but the vacation of 1846 found him again on the Mer de Glace, engaged in observations on the ablation of the surface of the glaciers, and the difference of movement between the surface and the underlying ice. His next and last visit to the Alps in 1850 was entirely occupied in putting the finishing touches to his survey of the Mer de Glace, which was for some years after its publication the only correct Alpine map in existence. At the close of the session of 1850-51 he started for Norway with the double purpose of observing a total eclipse of the sun visible at Bergen, and of comparing the phenomena of the arctic glaciers with those of the Alps. These objects were not attained without great fatigue and exposure; Forbes returned from Norway with health much impaired, and had scarcely recommenced his work when he was attacked by haemorrhage, the precursor of a long and dangerous illness. All through December he lay between life and death, but in January he was able to be removed to Clifton, which he made his headquarters for two years. During this enforced leisure he was constantly engaged in writing a very able “Dissertation on the Progress of Mathematical and Physical Science,” for the pages of the Encyclopaedia Britannica, and in preparing for the press a work on Norway and its Glaciers, similar in character to his Glaciers of the Alps, and scarcely yielding to it in picturesqueness of narrative or careful observation. In the summer of 1853 he was called from Clifton to Oxford to receive the honorary degree of D.C.L. During the three sessions of Forbes’s absence, his class work had been conducted by Professor Kelland, but the session of 1854-1855 found him again at his post, and he worked with but little interruption from illness until 1859, assisted latterly by Dr Balfour Stewart. In that year the current of his life was turned into another channel. Owing to the translation of Sir David Brewster to the principalship of the Edinburgh university, the principalship of the United College of St Andrews became vacant; Forbes offered himself as a candidate, and was successful. His commission bears date December 2, 1859, but he did not resign his professorship until the following April. The degree c∙f LL.D, was then conferred on him by the university which his own labours had so greatly benefited and adorned.

His new post, although it relieved him of the fatigue of constant lecturing, was no sinecure. The Scottish University Commission were then in full session, and in their investigations of the affairs, financial and other, of his own college, and of the university, the responsibility of supplying information and suggesting reforms fel l largely on him. A zealous reformer he always was, and he had not left behind him at Edinburgh that dauntless spirit of “Thorough” which saw only one straight road to a right principle, and pursued it, not without collisions, and often painful ones. The duties of his office were performed with scrupulous industry. His own college is indebted to him for a laborious examination and classification of its ancient charters. He found the collegiate church of St Salvator in a condition of tasteless neglect; he left it partially restored and greatly beautified. He occasionally lectured on glaciers, climate, heat, and others of his favourite subjects, and even strained his failing powers to complete his researches on the thermal conductivity of iron. For the latter, shortly before his death, the Keith medal was awarded to him.

In the spring of 1867 Forbes’s health gradually declined, and towards the end of September he set out with his wife and three daughters to Cannes, and afterwards went on to Hyères. His health now continued to improve until the middle of January, when he was again attacked by haemorrhage brought on by fatigue. He never sat up again, and while in that painful state the presidency of the Royal Society of Edinburgh was offered to him and declined. It was evident that a summer at Hyères was impossible, so he was conveyed, together with one of his daughters who was almost in the same sad condition as himself, to Clifton, where he lingered for eight months, awaiting his end with patient calmness, sustained by the deep and fervent religious faith which had characterized his boyhood, and which a life of active scientific research had strengthened rather than impaired. He died on the 31st of December 1868.

Forbes received the honorary degree of D.C.L. from Oxford, and that of LL.D. from the university of Edinburgh. The Royal Society of London awarded him their Rumford medal for his discovery of the polarization of heat, and their Royal medal for a paper on the influence of the atmosphere on the sun’s rays. By the Royal Society of Edinburgh the keith medal λvas thrice presented to him, and he filled the post of secretary to that body from 1840 till the failure of his health obliged him to resign it. In 1845 a pension of £200 a year was granted to him for his services rendered to science. He was fellow of the Royal Societies of London and Edinburgh, and of the Geological Society, corresponding member of the Imperial Institute of France, and associate or honorary member of the Bavarian Academy of Sciences, of the Academy of Palermo, of the Dutch Society of Sciences (Haarlem), of the Helvetic Society, of the Pontifical Society, of the Pontifical Academy of “Nuovi Lincei” at Rome, and of the Natural History Societies of Heidelberg, Geneva, and Vaud, and honorary member of the Royal Medical Society of Edinburgh, of the Cambridge, Yorkshire, St Andrews, and Isle of Wight Philosophical Societies, and of the Plymouth and Bristol Institutions.

A list of his scientific writings is to be found in the Royal Society Catalogue, but the following books may be mentioned as bearing more particularly on his glacier researches :— Travels through the Alps of Savoy, Black, Edin., 1843, 1845; Norway and its Glaciers, Black, Edin., 1853; Occasional Papers on the Theory of Glaciers, Black, Edin., 1859. See also Théorie des Glaciers de la Savoie, par Μ. le Chanoine Rendu (translated by Alfred Wills, edited by Professor George Forbes), Macmillan, Lond., 1874.

Forbes’s Life and Letters, by Principal Sħairp of St Andrews, Prof. P. G Tnit, and A. Adams-Reilly, was published by Macmillan, London, 1873.

FORBES, Sir John (1787-1861), M.D., was born at Cuttlebrae, Banffshire. He attended the Grammar School at Aberdeen, and afterwards entered Marischal College. Having for nine years been assistant-surgeon and surgeon in the navy, he in 1817 graduated at Edinburgh, and then commenced practice in Penzance, whence he removed to Chichester. He took up his residence in London in 1840, and was the same year appointed physician to the Prince Consort, and in 1841 physician to the Queen’s household. He was a fellow of the Royal Society, and D.C.L. of Oxford; and in 1853 he received the honour of knighthood. He died November 13, 1861, at Whitchurch in Berkshire.

Sir John Forbes was better known as an author and editor than as a practical physician. His works include the following :— Original Cases . . . illustrating the Use of the Stethoscope and Percussion in the Diagnosis of Diseases of the Chest, 1824; Illustrations of Modern Mesmerism, 1845; A Physician’s Holiday, 1st ed. 1849; Memorandums made in Ireland in the Autumn of 1852, 2 vols., 1853; Sight-seeing in Germany and the Tyrol in the Autumn of 1855, 1856. He was joint editor with Drs Tweedie and Conolly of The Cyclopaedia of Practical Medicine, 4 voLs., 1833-35; and in 1836 he founded the Br itish and Foreign Medical Review, which, after a period of prosperity, involved its editor in pecuniary loss, and ceased to exist, in consequence of the advocacy in its later numbers of doctrines obnoxious to the profession.