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of Pennsylvania against the excise laws. Mr. Barton has endeavoured to vindicate Mr. Rittenhouse for his connection with this Society; but his vindication is far from satisfactory. He did not attend their meetings; but as he retained the place of President, this must be considered as a direct avowal that he approved of their proceedings; for had he disapproved of them, it is quite obvious that he was bound as an honest man to throw up the office. Now as Mr. Barton does not say that any resignation took place, it is pretty clear that he retained his situation to the last. How far his being President of the democratic society of Philadelphia can be considered as approving of the enormities committed in France, and the desperate spirit of immorality displayed by the successive demagogues of that unhappy country, I cannot say; because I do not know the peculiar creed which was maintained and propagated by the democratic society of Philadelphia. That a republican should view the French Revolution with a favourable eye, in spite of the enormities which disgraced it, I can easily conceive ;

but that a philosopher, and a disciple of Newton, should view with complacency the unblushing propagation of atheism and immorality, is what I cannot bring myself to believe ; nor that a Christian, and a man of virtue, like Mr. Rittenhouse, should rejoice at the destruction of the Christian religion, and all the institutions for education in one of the finest countries of Europe.

Dr. Rittenhouse was elected a foreign member of the Royal Society on the 16th of April, 1795; but he' enjoyed this honour only a short time. His constitution was worn out, though he had not attained any extraordinary age; and he died on the 26th of June, aged 64 years. The account of his death by his nephew, Dr. Smith Barton, who attended him in his last illness, is so simple and interesting that I cannot avoid laying it before my readers :

“ The last visit I ever received from Mr. Rittenhouse was about the middle of June, 1796. He called at my humble habitation in Fifth-street, to inquire about my health, and to learn from me the result of the experiments and inquiries in which he knew I was at that time engaged, concerning the mode of generation and gestation of our opossum, an animal to whose economy and manners he had himself paid some attention, and whose history he justly considered as one of the most interesting in the whole range of

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" It was on this occasion that our excellent friend first informed me that he had received a diploma from the Royal Society. He observed, with a tone of voice, and with a certain expression of countenance, which were not calculated to afford me any pleasure, that a few years ago such a mark of respect from that illustrious body would have been received by him with pleasure and with pride.

" In fact, Mr. Rittenhouse, now and for some months past, was strongly impressed with the idea that his career of usefulness and virtue was nearly at an end. He had several times during the pre

ceding part of the spring and summer, intimated to me (and doubtless to others of his friends) his impressions on this head. In what precise condition of his system, whether physical or intellectual, these impressions were founded, I have only been able to form a distant and unsatisfactory conjecture.

“ A few days after this interview, viz. on the 22d. of June, I was sent for to visit Mr. Rittenhouse. I found him in his garden, where he loved to walk, and soon learned that he laboured under a severe attack of cholera, accompanied, however, with more fever than we generally find with this disease; and with a great increase of that violent pain and sense of oppression at the region of his stomach, to which he had been subject for at least thirty years. Notwithstanding his age, the debility of his system, and the unfavourable state of the season, I ventured to flatter myself that the attack would not prove mortal. On the following day, however, finding him no better, but rather worse, I requested permission to

I call in the aid of another physician; and having mentioned the name of Dr. Adam Kuhn, that Gentleman accordingly visited our friend in company with me during the remainder of his illness.

“ His febrile symptoms being very urgent, it was thought necessary to bleed our patient; and notwithstanding his great and habitual repugnance to the practice on former occasions, he now readily consented to the operation, on condition that I should perform it myself. The blood which was drawn exhibited a pretty strong inflammatory crust, and the operation seemed to give him a temporary relief from his pain. Soon after this his strength gradually declined; and on the third day of his illness it was but too obvious that our illustrious relative was soon to be separated from his friends. He expired without a struggle, and in the calmest manner, ten minutes before two o'clock on the morning of Sunday the 26th, in the presence of his youngest daughter, Mrs. Waters, and myself. His excellent wife, who had ever been assiduous in her attentions on her husband, both in sickness and in health, had retired from his chamber about two hours before, unable to support the awful scene of expiring genius and virtue.

." There can be no doubt, I think, that Mr. Rittenhouse, from the first invasion of his disease, or at least from the day when he was confined to his bed or room, entertained but little hopes of his recovery. He signed his will in my presence. He discovered no more solicitude about his situation than it is decorous and proper

in every good or great man to feel when in a similar situation. During the greater part of his illness he manifested the most happy temperament of mind : and it was only in the last lour or two of his life that his powerful intellects were disturbed by a mild delirium. About eight hours before he died, the pain in the region of his stomach being unusually severe, a poultice composed of meal and laudanum was applied to the part. In less than two hours after the application I called to see him, and upon asking him if he did not feel easier, he calmly answered in these memorable words, which it

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is impossible for me to forget, for they were the last he ever distinctly uttered, and they make us acquainted with the two most important features of his religious creed,— Yes, you have made the

way to God easier.' “ Such were the dying words, as it were, of our illustrious' relative and friend. He was dear to us both, to all his relatives and friends, and to his country. To me, let me add, he was peculiarly dear. The most happy and profitable hours of my life were passed in the society of this virtuous man. I followed his footsteps in the wilderness of our country, where he was the first to carry the telescope, and to mark the motions and positions of the planets. In the bosom of his family I listened to his lessons, as an humble disciple of Socrates or Plato. Science mixed with virtue was ever inculcated from his lips; but to me Mr. Rittenhouse was more than a friend and preceptor. He was a father and supporter. He laid the foundation of what little prosperity in life I now, or may in future, enjoy: and if it shall ever be my fortune, either by my labours or my zeal to advance the progress of science, or to reflect any honour upon my country, I should be the most ungrateful of men if I did not acknowledge and wish it to be known that it was David RITTENHOUSE who enabled me to be useful."

That the character and dispositions of Dr. Rittenhouse must have been excellent, is obvious from the high veneration in which he was held by all his countrymen, and by the annual and unanimous vote of the General Assembly of Pennsylvania in his favour for 13 years, at a period when they were divided into two most furious factions. That his honour and integrity were pure and unsullied we require no further proof than this: he led in Philadelphia a retired and sober life, never launching out into any extravagance, and indeed holding luxury in the utmost abhorrence; yet all the property which he ever acquired cost him no more than 13,525l. ; though he held for many years public offices of the most important kind, some of them lucrative ; and one, Treasurer to the State, in a time of public danger and distress, in which a man destitute of principles might have realized an immense fortune. Mr. Barton has brought the most satisfactory evidence that he was a sincere believer in the Christian religion, that he had studied its evidences, and satisfied himself of their force, though he seems to have reckoned as of no consequence the peculiar dogmas which distin guish the different Protestant sects which swarme in America. His liberality and benevolence were in all cases conspicuous. He advanced a considerable sum of money to enable the American Philosophical Society to discharge a debt which they had contracted. In 1793, when the yellow fever raged in Philadelphia, he employed Dr. Barton to attend several poor families in his neighbourhood who had contracted the disease. He supported, for some time, an Italian statuary, who had come to Philadelphia in quest of employment, but had been unsuccessful. Finally, he was, during the whole of his life, a violent and declared enemy to the slave-trade. ,

As to his works, he has left but few behind him. Nor shall we be surprised at this, if we consider the country in which he spent his life, the difficulties with which he had to struggle in the early part of his career, and the arduous contest which, during a period of 12 years, drew the whole attention of the Americans to politics, and which left behind it such a deterioration of moral character, such a state of agitation and discontent, as must long prevent any great advancement of the sciences in that boisterous and unsettled republic. Mr. Rittenhouse left behind himn 22 papers, all printed in the four volumes of the American Philosophical Society's Transactions, which have been already published. These papers are

, chiefly astronomical; and the most important of them all is the account of the transit of Venus in 1769, printed in the first volume, and drawn up by Ds. Smith.

ARTICLE II.

Experiments for determining the Draught of Carriages, with and

without Springs. Extracted from an Essay on the Construction of Roads and Carriages. By R. L. Edgeworth, Esq. F. R. S. M. R. I. A. and Civil Engineer.

THEORY shows that whilst the wheels of a carriage pass over an obstacle the load on the carriage must rise along with the wheels, unless it is supported by springs; but that if the load is hung upon springs, whilst the carriage-wheels tend to throw the load upwards, as they rise suddenly over an obstacle, the springs will bend, because they are opposed, not only by the weight, but by the vis inertiæ of the load acting downwards; and the load will consequently not be thrown up suddenly so high, as if there were no springs; for the weight cannot be thrown upwards instantly; it requires a certain time to throw any weight upwards through a given space, and it is well known that in all cases this time must be equal to that in which a body would fall through the same space. So that making allowance for the imperfection of springs, it is easy to calculate their utility in lessening the draught of a carriage over an obstacle, if the height of the obstacle, the velocity of the carriage, the height of its wheels, and of the load which rests on springs, be known.

Upon subjects of this sort, which are of such universal concern, the best possible proofs should be given of the truth of whatever is proposed for general adoption, particularly where popular prejudice is directly in opposition to what is advanced. Let the accuracy of models, and their resemblance to reality, be ever so great, the mind still requires what is real. The ploughman will not be convinced by experiments made on the models of ploughs, nor the

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waggoner or coachman by experiments on the models of coaches or waggons. It has been hitherto, therefore, a desideratum in mechanics to discover means of ascertaining precisely the power exerted by animals in drawing instruments of agriculture, as well as what is requisite to draw wheel carriages.

A machine for this purpose was presented to the Society for the Encouragement of Arts and Manufactures in 1771. It consisted of levers acting upon a spiral spring, in such a manner as to move an index that went through a considerable space. But as the power of the horse, and the resistance of the machine, varies continually; and as this machine showed only the greatest exertion of the power, without giving the sum of all its efforts, it was not satisfactory. It is possible to construct a machine upon this principle that will give the amount of the time and force employed in trials of this sort ; but more simple and satisfactory means have been discovered.

In page 50 of the first Report for May, 1808, of the Committee of the Highways, I have spoken of a perfect method of ascertaining the comparative force necessary to draw any two carriages. It appears to me to be my duty * to describe this contrivance in the present paper.

To elucidate the principle of this apparatus, two post-chaises were selected, the weights of which were nearly the same, their wheels were nearly of the same size, and they were alike in their general construction. To determine which of these could be drawn over the same obstacles with the greatest ease, one end of a rope 60 yards long was fastened to the splinter-bar of one of the chaises, and the other end of it was fastened to the splinter-bar of the other carriage. This rope had been previously made to pass round a light pulley six feet six inches diameter, which was placed horizontally, by means of a proper frame, on a two-wheeled carriage.

This pulley was sufficiently large to permit the carriages which were to be compared to run in a parallel direction at a sufficient distance from each other.

The foremost carriage was drawn forward by horses, and the two chaises were obliged to follow it. As the chaises were nearly of the same weight, they kept for some time together; but when either of them was retarded, it fell behind the other. An inconsiderable difference in the goodness of the parts of the road on which either carriage ran became sensible by the retardation of that carriage which ran upon the worst road.

If the machine carrying the pulley be drawn forward, the two other carriages must follow it; and if they are of equal weight, and equally well constructed, they must move on together, as they are drawn by the carriage with the pulley, provided the part of the road on which each of them moves be equally smooth and good; but if either of the carriages that are to be compared is inferior in

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* This essay was composed at the desire of the Chairman of the Committee of the House of Commons,

the