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failed him, and with the people at large he was exceedingly popular. In the year 1794, finding his health greatly impairede by his close attention to business, he obtained leave of absence from the elector, and employed sixteen months in travelling through various parts of the continent, especially Italy. During his absence, two very gratifying testimonies of respect and gratitude were borne to him by the Bavarians. The first was, the erection of a monument to commemorate his public services. The other was still more honourable to him: it was the resolution, already referred to, of the inmates of the Military Workhouse, when they heard that he was dangerously ill at Naples, to set apart an hour every evening to pray for his recovery. In 1795 Rumford returned to Bavaria, but left it almost immediately, to proceed on a visit to England. Here he was received with all distinction, and his opinion and advice were asked by all engaged in philanthropic schemes. To save himself the labour thus entailed upon him, he resolved to publish an account of his doings and experiments in Bavaria, and accordingly prepared for the press the two volumes of essays which go by his name. The only subject of general interest in these essays, apart from the purely scientific disquisitions, which remains to be mentioned by us, is that of fuel.

In undertaking to reform chimneys and fireplaces, Count Rumford had three objects in view—the saving of fuel, the prevention of smoke, and the avoidance of the injury to health arising from draughts. The extent of his services in this unpretending but most important department will be better estimated if we consider the state of fireplaces in most European countries fifty or sixty years ago. The most polished nations of antiquity,” says Dr Renwick, “had no other means of providing for the issue of the smoke of their fires than by leaving openings in the roof. They indeed appear, in some instances, to have heated apartments by flues circulating beneath the floors, which must have terminated in a vertical funnel, thus forming an approximation to the chimney; but there appears to be no instance of the arrangement of an open hearth and vertical flue until late in the middle ages. Chimneys and fireplaces of the latter date are still to be seen in the kitchens and halls of baronial mansions; but the hearths were of great size, the arched openings wide and lofty, insomuch that they could be entered by persons standing upright, and admitted seats to be placed on each side of the fire. The latter, indeed, were the only places where the warmth of the fire could be enjoyed without exposure to the currents of cold air continually rushing in to join the ascending column in the chimney. Even when an increasing scarcity of fuel compelled less extravagant modes of applying it to be sought, the arched opening remained of a large size, the fireplace of a depth equal in extent to its front, and the walls were carried back perpendicularly to the latter. In England, where coal had come into almost universal use as a fuel, the grates in which it was burnt were almost exact cubes, and were lined with cast-iron on the sides and back. The evils of these fireplaces may be recollected by all whose age reaches fifty; and they are remembered with feelings in which shuddering and scorching are strangely combined, but which are almost unknown, and scarcely to be imagined, by the present generation. Chimneys which did not smoke were the exception to the general rule; and the exposure of the surface ef the body to cold currents generated the acute pains of rheumatism, while the frequent alternations of an increased and checked perspiration caused colds, to be followed, in regular course, by pulmonary complaints. In this state of things Rumford undertook to remedy the manifold evils of the open fireplace.”

* Essays Political, Economical, and Philosophical ; by Benjamin, Count of Rumford, Knight of the Orders of the White Eagle and St Stanislaus; Chamberlain, Privy-Counsellor of State, and Lieutenant-General in the service of his most serene Highness the Elector Palatine, reigning Duke of Bavaria, &c. &c. &c.

Observing that the heat of a mass of blazing fuel in a grate consisted of two parts—that which radiated into the room, and served the purposes of warmth; and that which, by heating the column of air in the chimney, caused it to ascend, Rumford saw that an enormous saving could be effected by diminishing the size of the grate. Instead of a cubical mass of fuel, such as was generally used, he proposed to employ a grate of ordinarily broad front, but not deep backward, and with the sides not perpendicular to the front, but inclining. The effect of this was to limit the fire to the single function of warming the room by radiation from its front, while the mass of coal which had formerly been consumed without any benefit to the apartment was saved. In order, however, to prevent the smoking of the chimneys which would have arisen from this diminution of the burning mass, another change was necessary, and this was the narrowing the throat of the chimney, so as to allow no more air to pass through it than the precise quantity required to maintain the combustion. “The immoderate size of the throats of chimneys," says Rumford, “is the great fault of their construction. It is this fault which ought always first to be attended to in every attempt which is made to improve them ; for however perfect the construction of a fireplace may be in other respects, if the opening left for the passage of the smoke is larger than is necessary for that

purpose, nothing can prevent the warm air of the room from escaping through it; and whenever this happens, there is not only an unnecessary loss of heat, but the warm air which leaves the room to go up the chimney being replaced by cold air from without, draughts of cold air cannot fail to be produced in the room, to the great annoyance of those who inhabit it.”

Such is a general description of Count Rumford's alterations in fireplaces. The subject, however, was pursued by him to its minutest details, and illustrated by numerous and specific plans for curing smoky chimneys under all possible circumstances. He likewise invented various forms of stoves and grates, intended to exhibit the model perfection of an apparatus for heating rooms, or for cooking victuals. So thorough and complete was his investigation of the subject, that little remained afterwards to be added to his conclusions; and it may be said, that any case of the continuance of a smoky chimney after the publication of his essays, arose from a neglect or misapplication of the principles there developed.

The investigation of the subject of the construction of grates and fireplaces led Rumford to researches on heat, which ultimately assumed an almost purely scientific character. It is indeed a feature worthy of remark in Count Rumford's life, that, unlike the greater number of eminent scientific men, he did not begin by attention to the abstract doctrines of science, and carry these out into practical application, but he was led originally to a consideration of the doctrines through his desire of practical improvement. Always exhibiting scientific tendencies and talents, the circumstances of his life were such as to demand constant practical activity and a sacrifice of his purely scientific aspirations to present utility; and it was only in the latter part of his life that his inquiries and studies assumed an abstract character. The most important of these inquiries were in relation to heat, light, and the projectile force of gunpowder ; but as an enumeration of Rumford's scientific discoveries, or an examination of his claims to be considered a scientific discoverer, would be beyond the scope of the present Tract, we shall only mention that Count Rumford is entitled to the honour of having been the first to explain the manner in which heat is propagated in fluids, having demonstrated that the boiling of water over a fire takes place not in consequence of the travelling of the heat upwards through the fluid by conduction, but in consequence of the

perpetual circulation of the particles of the fluid themselves, the heated particles rising, and the cooler descending. QUITS THE BAVARIAN SERVICE-RESIDENCE IN LONDON AND

PARIS-DEATH AND CHARACTER. To return to Count Rumford's life. After some stay in Great Britain, he returned to Munich in 1796, accompanied by his daughter, who had come over from America at his request, her mother having died in 1792. What were Count Rumford's relations with America during the long interval of his absence from it, we have no means of ascertaining ; as far

inferred, however, he seems to have maintained little correspondence with his former friends in the United States till after his wife's death; and one cannot help remarking the unpleasing circumstance, that while on one side of the Atlantic the husband was enjoying an honourable position, and filling a large

as can

space in the public eye, the wife and daughter continued during the life of the former to reside on the other.

Rumford, on his return to Munich, was occupied in very important affairs. The advance of the French republican army under Moreau obliged the elector to quit the capital, leaving a council of regency, with Rumford at its head. "Rumford succeeded in the arduous task of freeing Bavaria from the invasion, and his conduct on this occasion increased his reputation with the elector and with the people. Among other tokens of the elector's gratitude for his services, he was permitted to settle one-half of the pension which he enjoyed on his daughter, to be paid during her lifetime. In 1798 the elector, partly with a view to gratify him with an honour which he knew he desired, and partly to afford him another opportunity of relaxation for the improvement of his health, appointed him his ambassador at the court of Great Britain. On arriving in London, however, Rumford found, that in consequence of the English legal fiction, by which a born subject of the country is declared incapable of ever alienating his allegiance, he could not be received as the Bavarian ambassador. Mortified as he must have been by this circumstance, and still more deeply grieved by the loss of his friend and patron, the Elector Charles Theodore, who died in 1799, Rumford contemplated returning to spend the remainder of his life in the land of his birth. In compliance with a formal invitation which he received from the United States government, he was making preparations for his return, and had written to a friend to secure a cottage in the vicinity of Boston, as a “quiet little retreat," when he was led to change his design, and remain in London, in the society of which he occupied a conspicuous place. During several years, a great part of Count Rumford's time was devoted to the interests of the Royal Institution, of which indeed he may be considered the founder. The objects of this institution, now one of the recognised scientific establishments of the world, and which can boast of having given employment to such men as Young, Davy, Brande, and Faraday, were “to diffuse the knowledge and facilitate the general introduction of useful mechanical inventions and improvements, and to teach, by courses of philosophical lectures and experiments, the application of science to the useful purposes of life.” Such an institution was precisely the one which Rumford was qualified to superintend; and in its early history, the influence of his peculiar habits of thought is discernible in the choice of subjects for investigation by the members. Subsequently, the institution assumed the high scientific character which it yet holds.

In 1802, Count Rumford left England, and spent some time in travel. Revisiting Munich, he found the workhouse which he had planned, and which had been instrumental in producing so much good, abolished, and the new elector, Maximilian, friendly indeed, but indisposed to follow the footsteps of his predecessor.

Accordingly, after assisting in modelling a Bavarian academy of sciences, he took farewell of his adopted country, and went to reside in Paris, retaining an income of about £1200 from the Bavarian court. At the same time his daughter returned to America, her father having abandoned his intention of returning along with her. In Paris, Count Rumford appears at first to have gained that good-will' and esteem which had attended him so remarkably during his previous life; and not long after he began his residence there, he contracted a second marriage with the widow of the celebrated Lavoisier, put to death during the French Revolution. From 1804 to 1814 he resided with his wife at Auteuil, a villa at a short distance from Paris, the property of Madame Lavoisier, and the scene of many of her former husband's discoveries. Here Rumford employed himself in scientific pursuits of a miscellaneous nature. The union of the American-born citizen of the world with the widow of the illustrious Frenchman does not appear to have been a happy one; and there is evidence that, towards the end of his life, Rumford had become unpopular in Parisian society. Cuvier attributes this to a certain coarseness and want of urbanity of manner; possibly, however, the fault was less in the person criticised than in the Parisian standard of criticism, for the charge seems inconsistent with the tenor of Rumford's life.

Rumford's death took place at Auteuil on the 21st of August 1814, in the sixty-second year of his age. He left some bequests for the promotion of science in America; the rest of his property, which does not appear to have been great, he left to his relatives. His only daughter inherited the title of Countess of Rumford, with the continuation of her father's Bavarian pension. She is, we believe, still alive (1847), and has long resided in Paris.

Rumford, whose memoirs we have now detailed, was not a faultless character, or a person in every respect exemplary; but making due allowances for circumstances in which he was at the outset unfortunately placed, and keeping in mind that every man is less or more the creature of the age in which he lives, we arrive at the conclusion, that few individuals occupying a public position have been so thoroughly deserving of esteem. The practical, calm, and comprehensive nature of his mind, his resolute and methodical habits, the benevolence and usefulness of his projects, all excite our admiration. Cuvier speaks of Rumford

having been the benefactor of his species without loving or esteeming them, as well as of holding the opinion, that the mass of mankind ought to be treated as mere machines.” A remark this which is applicable to not a few men who have been eminent for labours of a humane description, and which naturally gives rise to this other remark—that a good intellectual method, directed to practical ends, is often of more value to mankind than what is called a good heart.


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