contrivances, two kinds of equilibrium, which, though they appear very much alike in times of quiet, yet, in the moment of agitation and difficulty, are discovered to be very different from one another. The one is tottering and insecure, in so much that the smallest departure from the exact balance leads to its total subversion. The other is stable, so that even a violent concussion only excites some vibrations backward and forward, after which every thing settles in its own place. Those governments in which there is no political liberty, and where the people have no influence, are all unnavoidably in the first of these predicaments: those in which there is a broad basis of liberty, naturally belong to that in which the balance re-establishes itself. The same weight, that of the people, which in the first case tends to overset the balance, tends in the second to restore it: and hence, probably, the great difference between the result of the French Revolution, and of the revolutions which formerly took place in this country.

It will be happy for mankind, if they learn from these disasters, the great lessons which they seem so much calculated to enforce, and if while the people reflect on the danger of sudden innovation, their rulers consider, that it is only by a gradual reformation of abuses, and by extending, rather than abridging, the liberties of the people, that a remedy can be provided against similar convulsions.

But I return willingly from this digression, to those branches of knowledge, where, in describing what Mr. Robison has done, the language of truth and of praise will never be found at variance with one another.

In autumn 1799, this country had the misfortune to lose one of its brightest ornaments, Dr. Black, who had laid the foundation of the Pneumatic Chemistry, and discovered the principle of Latent Heat. The Doctor had published very little; and his discoveries were more numerous than his writings. His lectures, however, had drawn much attention; they presented the first philosophical views of chemical science; they were remarkable for their perspicuity and elegance, and this, joined to the simplicity and gracefulness of manner in which they were delivered, made them universally admired. It was now proposed to publish these lectures; but this required that they should be put into the hands of some one able to perform the part of an editor, and to prepare for the press the notes from which the Doctor used to read his lectures. The person naturally thought of was Mr. Robison, one of Dr. Black's oldest friends, and so well skilled in chemistry, that no one could be supposed to execute the work with more zeal or more intelligence. The task, however, was by no means easy. Dr. Black, with a very large share of talent and genius, with the most correct taste and soundest judgment, with no habits that could dissipate his mind, or withdraw it from the pursuits of science, was less ardent in research, and less stimulated by the love of fame, than might have been expected from such high endowments. A

state of health always delicate, and subject to be deranged by slight accidents, was probably the cause of this indifference. Hence the small number of his writings, and his sudden stop in that career of discovery on which he had entered with such brilliancy and success. Of much that he had done, the world had never heard any thing, but from verbal communication to his pupils; and on the subject of latent heat, no written document remained to ascertain to him the property of that great discovery. The only means of repairing this loss, and counteracting the injustice of the world, was the publication which Professor Robison now undertook with so much zeal, and executed with so much ability. Dr. Black had used to read his lectures from notes, and these often but very imperfect, and ranged in order by marks or signs only known to himself. The task of editing them was therefore difficult, and required a great deal both of time and labour, but was at last accomplished in a manner to give great satisfaction. The truth, however, is, that the time was past when this work would have met in the world with the reception which it deserved. Chemical theories had of late undergone great changes, and the language of the science was entirely altered. Dr. Black, on the subject of these changes, had corresponded with Lavoisier, and the mutual respect of two great men for one another was strongly marked in the letters which passed between them. The Doctor had acceded to the changes proposed by the French chemist, and had even adopted the new nomenclature; but his notes had not undergone the alterations which were necessary to introduce it throughout. It would now have been difficult to make those alterations; and Mr. Robison, who was not favourable to the new chemistry, did not conceive that by making them he was permanently serving the interest of his friend. He conceived, indeed, that there was unfairness in the means employed by Lavoisier, for bringing Dr. Black to adopt the new system of chemistry; and has thrown out some severe reflections on the conduct of the former, which appear to me to rest on a very slight foundation.

It was quite natural for a man, convinced, like Lavoisier, of the importance of the improvements which he had made in chemistry, to be desirous that they should be received by the most celebrated Professor of that time,-by the very man, too, whose discoveries had opened the way to those improvements. His letters to Dr. Black, contain expressions of respect and esteem, which, I confess, appear to me perfectly natural, and without any thing like exaggeration or deceit. Indeed it is not probable that M. Lavoisier, even if he could himself have submitted to flatter or cajole, could conceive that any good effect was to arise from doing so, or that there was any other way of inducing a grave, cautious, and profound philosopher, to adopt a certain system of opinions, but by convincing him of their truth. He had, with those who knew him, the character of a sincere man, very remote from any thing like art or affectation. We must therefore ascribe the view

which Mr. Robison took of this matter, to the same system of prejudices on which we have had already occasion to animadvert. Such, indeed, was the force of those prejudices, that he considered the chemical nomenclature, the new system of measures, and the new calendar, as all three equally the contrivances of men, not so much interested for science, as for the superiority of their own nation. Now, whatever be said of the calendar, the project of uniform weights and measures is admitted to be an admirably contrived system, which Britain is now following at a great distance; and the new nomenclature of chemistry to be a real scientific improvement, adopted all over Europe. Many of the radical words may depend on false theories, and may of course require to be changed; but though the matter pass away, the form will remain; the words of the language may perish, but the mould in which the language was cast will never be destroyed.* The Lectures appeared in 1803.

The last of Mr. Robison's works was one which he had long projected, though he now set about the completion and arrangement of it for the first time. It was entitled, Elements of Mechanical Philosophy, being the Substance of a Course, of Lectures on that Science." Mechanical philosophy" was with him a favourite expression; it was understood as synonymous with natural philosophy, and included the same branches. The first volume, the only one he lived to finish, included dynamics and astronomy, and was published in 1804. It is a work of great merit, and is accessible to those who have no more than an elementary knowledge of the mathematics. The short view of the phenomena prefixed to the physical astronomy is executed in a masterly manner. The same may be said, and perhaps even with more truth, of the physical astronomy itself; for there are very few of the elementary treatises on that branch of science which can be compared with it, either for the facility of the demonstration, or the comprehensiveness of the plan. The first part is meant to be popular and historical, and is so at the same time that it is philosophical and precise. The work is indeed highly estimable, and is entitled to much more success in the world than it has actually had.

We have already taken notice of Mr. Robison's illness, with which he had been now afflicted for the long period of 19 years. His sufferings, though not equal, had been often extremely severe. They had occasionally rendered him unable to discharge his duty in the college, and of late his friend, the Rev. Dr. Thomas Macknight, had, with great kindness and ability, frequently supplied

The high opinion which Mr. Robison elsewhere expresses of Lavoisier, is very remarkable. In his Astronomy, published a year after the Lectures, in stating Hook's anticipation of the principles of gravitation, he concludes thus: "It is worthy of remark, that in this clear and candid and modest exposition of a rational theory, Hook anticipated the discoveries of Newton, as he anticipated with equal distinctness and precision, the discoveries of Lavoisier, a philosopher inferior perhaps only to Newton."-(Elements of Mechanical Philosophy, p. 285.)

his place. Against such a continuance of ill health, with so little hopes of recovery as could be entertained for a long time past, hardly any mind could be expected to remain in full possession of activity and vigour. This is the more difficult, as the valuable medicine which alone in such cases can assuage pain, contributes itself at length to weaken the mind, and to destroy its energy. The combat which Mr. Robison had maintained against these complicated evils, had indeed been wonderfully vigorous and successful, and the last of his works is quite worthy of his days of most perfect health and enjoyment.

The body could not resist so well as the mind. In the end of January 1805, he was suddenly seized with a severe illness, which put an end to his life in the course of 48 hours. There was a general disturbance of the system, which, without having the character of any defined disease, exhibited those symptoms of universal disorder which denote a breaking up of the constitution, and never fail to terminate fatally.

On reviewing the whole of his character, and the circumstances of his life, it is impossible not to see in him a man of extraordinary powers, who had enjoyed great opportunities for improvement, and had never failed to turn them to the best account. He possessed many accomplishments rarely to be met with in a scholar, or a man of science. He had great skill and taste in music, and was a performer on several instruments. He was an excellent draughtsman, and could make his pencil a valuable instrument either of record or invention. When a young man, he was gay, convivial, and facetious, and his vers de société flowed, I have been told, easily and with great effect. His appearance and manner were in a high degree favourable and imposing; his figure handsome, and his face. expressive of talent, thought, gentleness, and good temper. When I had first the pleasure to become acquainted with him, the youthful turn of his countenance and manners was beginning to give place to the grave and serious cast, which he early assumed; and cer tainly I have never met with any one whose appearance and conversation were more impressive than his were at that period.

Indeed his powers of conversation were very extraordinary, and when exerted, never failed of producing a great effect. An extensive and accurate information of particular facts, and a facility of combining them into general and original views, were united in a degree of which I am persuaded there have been few examples. Accordingly, he would go over the most difficult subjects, and bring out the most profound remarks, with an ease and readiness which was quite singular. The depth of his observations seemed to cost him nothing; and when he said any thing particularly striking, you never could discover any appearance of the self-satisfaction so common on such occasions. He was disposed to pass quite readily from one subject to another; the transition was a matter of course, and he had perfectly, and apparently without seeking after it, that light and easy turn of conversation, even on scientific and profound

subjects, in which we of this island are charged by our neighbours with being so extremely deficient.

The same facility, and the same general tone, was to be seen in his lectures and his writings. He composed with singular facility and correctness, but was sometimes, when he had leisure to be so, very fastidious about his own compositions.

In the intercourse of life, he was benevolent, disinterested, and friendly, and of sincere and unaffected piety. In his interpretation of the conduct of others, he was fair and liberal, while his mind retained its natural tone, and had not yielded to the alarms of the French Revolution, and to the bias which it produced.

His range in science was most extensive; he was familiar with the whole circle of the accurate sciences, and there was no part of them on which, if you heard him speak or lecture, you would not have pronounced it to be his fort, or a subject which he had studied with more than ordinary attention. Indeed, the rapidity with which his understanding went to work, and the extent of ground he seemed to have got over, while others were only preparing to enter on it, were the great features of his intellectual character. In these he has rarely been exceeded. With such an assemblage of talents, with a mind so happily formed for science, one might have expected to find in his writings more of original investigation, more works of discovery and invention. I must remark, however, that from the turn his speculations and compositions took, or rather received from circumstances, we are apt to overlook what is new and original in a great part of them. An article in a dictionary of science must contain a system, and what is new becomes of course so mixed up with the old and the known, that it is not easily distinguished. Many of Mr. Robison's articles in the Encyclopædia Britannica are full of new and original views, which will only strike those who study them particularly, and have studied them in other books. In Seamanship, for example, there are many such remarks; the fruit of that knowledge of principle which he combined with so much experience and observation. Carpentry, Roof, and many more, afford examples of the same kind. The publication now under the management of Dr. Brewster, will place his scientific character higher than it has ever been with any but those who were personally acquainted with him. With them, nothing can add to the esteem which they felt for his talents and worth, or to the respect in which they now hold his memory.

ARTICLE II.

Account of an Accident which happened in a Coal-Mine at Liege in 1812. By Thomas Thomson, M.D. F.R.S.

In the preceding volumes of the Annals of Philosophy a variety of dismal accidents has been detailed, which occurred in the coal