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if we are not greatly mistaken, the infinuation had then never appeared.

Having finished his introduction, Mr. Murray proceeds to make extracts from M. Bouguer's Traité du Navire, and from comparing fome of them with the original, they appear, to be done with fufficient accuracy. His own remarks also which regard the practical part of thip-building, are very proper, and tend to elucidate the fubject. We wish we could fay the fame with regard to thofe made on the mathematical proceffes; but in our opinion, the work would not have been at all the less valuable, if thefe had been wholly omitted. Thus in pag. 49, our author feems to blame Mr. Bouguer for introducing a fluxionary investigation of the fine of the angle of incidence; and inftead of the Frenchman's proçefs, has given another method of his own for finding it by the doctrine of right-angled triangles. But it may not be amifs to hint to our Author, that the fide Ee in his own figure, is not a right-line, but a curve; and that it was for this very reafon that M. Bouguer had recourfe to a fluxionary procefs. We could therefore with, that Mr. Murray had contented himself with giving the refult of thefe curious investiga tions of his author. Had he purfued this method, we fhould not have feen the weak remarks he has made in the following page, on the folution of one of the moft intricate and curious problems in mechanics.

It would extend this article too far, if we attempted to give the fubftance of the work before us, which is only a concife abridg ment of a much larger treatise; we fhall therefore content ourfelves with giving the fubftance of M. Bouguer's conclufion, as tranflated by Mr. Murray.

After having, to the utmoft of my power, fays our author, executed every part of the engagement I undertook, it will be proper now to recapitulate the principal things I have explained, efpecially fuch as relate to the figure of the fhip; and I fhall make no fcruple again to affirm, that, I believe, I have given infallible rules to the builders, to determine their choice of the different plans that may be presented to them of the fame ship. We have, in the fecond book, explained all that concerns a fhip while a-float or at reft: we may know if the whole weight be proportional to the folidity of the immerged part; if she has stability or force to carry fail; or if fhe carries her guns high enough out of the water and, in the third book, we have given proper rules to affure us fhe will fail well; drive but little, when clofe hauled upon the wind, and readily anfwer all the motions of the helm. All the other qualities are fubmitted to the proof of a calculation, which cofts but little labour: even fuch accidents as feem to depend on very irregular caufes are confidered; fuch as the duration of the vibrations occafioned by rowling, and 3 thofe

thofe of pitching; we may judge of them by examining the dif tribution of the weights, and in what manner every particular weight is fupported in every different circumftance.

Geometricians think no labour too hard, and do not fatisfy themselves with what knowledge they have acquired, but are continually pufhing their refearches to the higheft pitch; notwithftanding all this, we must fometimes have recourse to experiments on fhips already built, which may ferve as a term of comparison. By these experiments we may, in an inftant, discover things which could not be done any other way, without a great deal of labour; and, in forming another fhip, it may fuffice to take notice of their different dimenfions, and the neceffary causes that may occafion some alterations.

We have endeavoured, out of an infinite number of forms, to pick out the best; and where the difpofition of different parts contribute to carry a certain property to a higher degree, we have fearched the most advantageous combination, to determine the maximum. We may, with certainty, make which property we please predominate, and at the fame time know how far we may carry the others.

We have fhewn, that the extreme breadth fhould be five twelfths of the length, from the forepart, which is the pofition beft fuited to make the fhip anfwer the motions of the helm; but it must be carried a little further forward, to make her fteer well by the affiftance of the fails, though, by this means, the bow will become fuller, to the prejudice of her failing, and of that property which fhould make a fhip lefs fubject of driving to the leeward. It will be impoffible to reconcile thefe four properties; and, that we may not lofe too much of any one of them, we muft refolve to lose a part of the others; and the fureft way, in moft cafes, will be to embrace that which most favours the action of the rudder.

'We have, in the first book, explained feveral methods of defcribing the midfhip frame, which may be improved by the remarks in the fecond and third books.

Suppofe we cannot perfuade ourselves to abandon the common practical rules, nor venture at once to go to the utmost point of perfection, yet it is to be wifhed, that the breadth and depth should bear but a very small proportion to the length; it is a matter of great importance, and merits the utmost attention of the builders. The fection of the midship frame fhould be a triangle in light frigates, but a rectangle in fhips built for burthen. In thefe laft, the breadth is continued the fame as in midfhips, for a confiderable space, nearly the fifth part of the whole length. The common rules are very well adapted to the building of fuch ships, and want very little amendment, but are very deficient in the frigates, which begin to narrow both fore and aft, from the RER, Sept. 1765.

very

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very midfhip frame. The fhips of war, as it were, keep a mean betwixt these two; they are fhips of burthen, but their great weight is fituated in a very inconvenient manner, their center of gravity being too near their metacenter; they muft, on that account, and on account of carrying their metal, be broader in proportion than other ships.

The principal dimenfions being established, we may form the ribbands, and fo the work will be compleated. We may ufe the method of approximation, delivered in the XIth chapter of the firft fection of the first book; or conform to the tables, which we have with great pains calculated, and inferted at the end of the laft fection, that the practical part may receive all the benefit that may accrue to it from theory.'

Mr. Murray next proceeds to give an abridgment of what Duhamel has faid in his fecond edition, on the center of gravity; but as this part of the work cannot be understood without the figures that accompany it, we must refer the reader to the work itself, which contains many ufeful obfervations on that important fubject. Our Author has concluded this part with fome experiments, made, he tells us, by one of our own countrymen, whose abilities are unexceptionable. They appear, indeed, to be made, with great accuracy, and prove that we fhall gain confiderably by placing the midship frame before the middle, perhaps at near two thirds of the length from the after end. We could however have wifhed, that the ingenious experimenter had investigated the cause of this, as his remarks on what he calls the friction of the water, feem to indicate that he does not want abilities. Perhaps thefe experiments may induce fome of the mathematicians to undertake the task, as it would be doing important fervice to their country.

The work is concluded with the method of bevelling the cant timbers by the diagonal ribbands, &c. and fome obfervations on the mafting of fhips; with the proportions used in England, and particularly in the royal navy.

B.

Continuation of the Account of Dean Swift's Pofthumous Pieces: See our laft Month's Review, p. 156.

N our two former articles relating to thefe pofthumous wri

I tour of the inimitable Dean, we have proceeded about half

way through the collection; and now we come to, 1. A tract entitled On the death of Mrs. Johnson.'-Of this lady (the very excellent Stella) we have frequently had occafion to make confiderable mention in our Reviews. In the account of Lord

Onery's

Orrey's remarks on the life and writings of Dean Swift we expatiated pretty largely on the fuppofition of her being the (concealed) wife of our Author; and alfo on the report of her being his fifter; and in the Review of Dr. Delany's obfervations on Lord Orrery's Remarks, we likewife gave our Readers an abftract of what the obferver had offered, in endeavouring to account for the Dean's mysterious conduct, in regard to a woman of fuch transcendent merit-Farther, in our account of Mr. Dean Swift's Effav on the Life, Writings, and Character of Dr. Jonathan Swift, we inferted fome additional anecdotes † and strictures on this curious fubject: to all which, we now refer our Readers, by way of introduction to the enfuing particulars concerning the charming but unfortunate Stella, written by the hand of what fhall we call him-her friend, her brother, her lover, or her husband?

This day, being Sunday January 28th, 1727-8, about eight o'clock at night a fervant brought me a note, with an account of the death of the trueft, moft virtuous, and valuable friend, that I or perhaps any other perfon ever was blessed with. She expired about fix in the evening of this day; and, as foon as I am left alone, which is about eleven at night, I refolve, for my own fatisfaction, to fay fomething of her life and cha

racter.

She was born at Richmond in Surrey on the thirteenth day of March, in the year 1186. Her father was a younger brother of a good family in Nottinghamshire, her mother of a lower degree; and indeed the had little to boast of her birth. I knew her from fix years old, and had fome fhare in her education, by directing what books fhe fhould read, and perpetually inftructing her in the principles of honour and virtue; from which the never fwerved in any one action or moment of her life. She was fickly from her childhood until about the age of fifteen : But then grew into perfect health, and was looked upon as one of the moit beautiful, graceful, and agreeable young women in London, only a little too fat. Her hair was blacker than a raven, and every feature of her face in perfection. She lived generally in the country, with a family, where the contracted an intimate friendship with another lady of more advanced years. I was then (to my mortification) fettled in Ireland; and, about a year after, going to vifit my friends in England, I found fhe was a little uneafy upon the death of a perfon on whom she had fome dependance. Her fortune, at that time, was in all not above fifteen hundred pounds, the intereft of which was but a fcanty maintenance, in fo dear a country, for one of her fpirit.

See Review, Vol. V. F. 414. † Ibid. Vo!. XII. p. 244.

Q2

Ibid. Vol. XI. p. 62.

Upon

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Upon this confideration, and indeed very much for my own fa tisfaction, who had few friends or acquaintance in Ireland, I prevailed with her and her dear friend and companion, the other lady* to draw what money they had into Ireland, a great part of their fortune being in annuities upon funds. Money was then at ten per cent. in Ireland befides the advantage of turning it, and all neceffaries of life at half the price. They complied with my advice, and foon after came over; but, I happening to continue fome time longer in England, they were much difcouraged to live in Dublin, where they were wholly ftrangers. She was at that time about nineteen years old, and her perfon was foon diftinguished. But the adventure looked fo like a frolic, the cenfure held, for fome time as if there were a fecret history in fuch a removal; which, however, foon blew off by her excellent conduct. She came over with her friend on the in the year 170--; and they both lived together until this day, when death removed her from us. For fome years past, he had been vifited with continual ill-health and several times, within thefe two years her life was defpaired of. But, for this twelve-month paft, fhe never had a day's health; and properly speaking, fhe hath been dying fix months, but kept alive, almost against nature, by the generous kindness of two phyfi cians, and the care of her friends. Thus far I writ the fame night between eleven and twelve.

Never was any of her sex born with better gifts of the mind, or more improved them by reading and conversation. Yet her memory was not of the beft, and was impaired in the latter years of her life. But I cannot call to mind that I ever once heard her make a wrong judgment of perfons, books, or affairs. Her advice was always the best, and with the greatest freedom, mixed with the greateft decency. She had a gracefulness fomewhat more than human in every motion, word, and action. Never was fo happy a conjunction of civility, freedom, eafiness and fincerity. There feemed to be a combination among all that knew her, to treat her with a dignity much beyond her rank: Yet people of all forts were never more eafy than in her company. Mr. Addifon, when he was in Ireland, being introduced to her, immediately found her out; and if he had not foon after left the kingdom, affured me he would have ufed all endeavours to cultivate her friendship. A rude or conceited coxcomb paffed his time very ill, upon the least breach of respect; for in such a cafe fhe had no mercy, but was fure to expofe him to the contempt of the ftanders by; yet in fuch a manner as he was afhamed to complain, and durft not refent. All of us, who had the happiness of her friendship, agreed unanimously, that, in an afternoon or evening's converfation, the never failed before we parted of delivering the beft thing that was faid in the company. Some,

• Mrs. Dingley.

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