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Tow tube, the ball will be impelled from the piece with a much less degree of velocity than if the chamber were shorter and wider, the charge of powder continuing the same. Hence, also, it is easy to conceive, that the powder fires the quicker the less distance the grains lie from each other. Now since of all figures under the same circumference, the globe con tains the greatest space, so that the particles or grains of powder it contains will lie nearer to each other than in any space of the same magnitude ; therefore there can be no doubt but the same quantity of powder will fire sooner in a globular space than in a space of any other form. It should therefore be endeavoured to make the cavity behind the ball as near as posible globular. For if it could be made exactly so, the velocity of the ball would receive a confiderable increase from such a figure. The effect would be so much the greater if the powder could be fired in the middle, since in this case the fire would extend fooner to all the extremities. There seems to be many difficul. ties which render this method impracticable. Perhaps fome experienced practitioner may find means to overcome these difficulties, and put these things in practice. It is sufficient for our present purpose to have pointed out the circumstances which contribute particularly to the making a chamber to advantage, and to judge of their advantage and disadvantage. It is to be observed, that the more the force of powder may be increased in this manner, the cannon ought to be the stronger in the part where its greatest force is exerted.'
M. Euler afterwards proceeds to examine what diminution of · velocity should be allowed on account of the powder's not firing at once: and to shew, by an analytical process, how the gradual firing of the powder may be estimated by calculation : but the extracts we have already given muft serve as specimens of this diffuse and elaborate performance. We shall only observe, that, as Mr. Robins's other engagements and immature death, at the age of 44, prevented his adding the geometrical illuftrations and proofs which he intended, and executing his design of publishing an enlarged edition of his New Principles of Gunnery, the present work will, in some measure, fupply the loss : and mathematicians, conversant with this subject, will have an opportunity of examining the calculations of M. Euler, of comparing them with Mr. Robins's experiments and theory, and of refuting any objections which he urges against them, so far as they are erroneous and insufficient. The subject of the ioitial velocity of a ball projected from a given barrel with a given charge, is peculiarly important to the improvement of artillery, and deserves accurate investigation. M. Euler has many remarks on this problem, on the resistance of the air, on the cause of the doubly incurvated motion of a ball, which he sup
poses to be its figure, and not, as Mr. Robins conceived, its 'rotatory motion ; on the composition of gunpowder ; on the quantity of charge for producing the greatest velocity ; on the length of pieces, and on a variety of other particulars, tending to the improvement both of the principles and practice of gunnery: the tables annexed to this work will serve to facilitate the investigation of the true path of a projectile; more especially if it ihould be found, upon trial, that all cases in gunnery may be solved by them with little more trouble than by the vulgar hypothesis of Galileo.
Art. II. Two Cafes of the Hydrophobia ; with Observations on that
Disease; together with an Account of the Cæsarian Section, as it was lately performed at Leicester. By J. Vaughan, MD. 8vo. 2 s. 6 d. Payne. 1778. HOUGH both the cases here related terminated fatally ;
and though no noftrum for the cure of the hydrophobia, or even successful method of treating it, is to be found in this little treatise ; the Public are nevertheless obliged to the Author for the information which may be collected from these two histories of an obscure and dreadful disease. The symptoms are here minutely described, as they occurred; together with the methods which the Author pursued, in attempting to relieve the patients; as also the appearances which were observed after death, on examining those parts which seemed to have been more peculiarly affected in the living subject.
The first of these patients had undergone all the severities attending the sea bathing usually practised on these occasions; he had likewife taken the celebrated Ormskirk medicine : nevertheless, in about a month after the bite, the hydrophobia appeared. The progress of the disease does not seem even to have been retarded (excepting a short feeming suspension) by the exhibition of musk, mercury, and opium in combination, and given in very large doses. Of the latter, particularly, from which much advantage might be expected as an antispasmodic, 57 grains were swallowed in the space of 14 hours, without producing any lafting sedative effect.
It is highly worthy of observation, that though between 20 and 30 persons were bit by the same dog that wounded this patient, some of whom took the Ormskirk medicine, others only bathed, and the rest employed no remedy whatever, not one of them felt the least ill effect but himself. This uncertainty of the infection's taking place, after the bite of a mad animal, has doubtless greatly contributed to the temporary reputation which various prophylactics, or supposed preservatives against this disease, have successively acquired, and to which there is .
perhaps too much reason to fear that not one of them may be justly intitled.
The other patient felt no symptoms of the hydrophobia till nine months after he had been bit. The disease, treated nearly as before, was still more rapid in its progress, and equally fatal in its termination.
On dissecting the first of these patients, the Author attentively examined all those parts of the body from which he could expect to derive any information, with respect to the nature or seat of the distemper. The abdominal muscles, and viscera, were found in a perfectly sound state ; nor did the stomach, liver, or contents of the thorax, shew the least signs of disease.
The pain felt at the scrobiculus cordis, and the difficulties and horror attending deglutition, could by no means be accounted for on an inspection of the parts concerned. The diaphragm had not undergone the least change: no veftige of inflammation could be perceived in the wesophagus; nor upon the velum pendulum palati : nor could any morbid appearances be perceived either in the interior surface of the fauces, nor in the superior part of the larynx and pharynx, nor in the glottis.—The brain was not examined.
As a prophylactic, or preventive, it has been judiciously proposed to cauterize the part with a red-hot iron, immediately after the bite. On this head the Author offers what we confider as an improvement on this practice. He recommends a dilatation of the wound, if it should be small, and then filling it with gunpowder, and setting fire to it.-Independent of the posible good effects which may result from the chemical action of the vitriolic acid or phlogiston on the poison, we should think that the infantaneity of the combustion is likely, in general, to excite less horror and pain than the comparatively flow and protracted torture produced by a hot iron.
To these two unfortunate cases a third, of a different kind, is added, which relates to the Cæfariar section, performed on a woman at the Leicester infirmary. On making the incision, though the placenta immediately protruded, the child was extracted, without the least injury, in the course of a few seconds, and with very little loss of blood. The mother however died on the fourth day :--- a consequence,' says the Author, that, I believe, will very generally follow such a wound of the uterus, with its unavoidable exposure to the air.'-The child, who was baptized under the name of Julius Cæfar,' is a healthy fine boy, now four months old, and likely to live.'
1 2 mo.
ART. III. The Incas; or, the Destruction of the Empire of Peru, By M. Marmontel.
2 Vols.' Os. Nourse, &c. 1777 . T has been juftly objected to the mode of writing which
this universally admired Author has adopted in this work, as well as in his Belisarius, that it requires an union of fiction and truth which is attended with material inconveniences. Unless the reader be perfectly master of the true history with which the fi&titious narrative is blended, he will be in continual danger of confounding them in his ideas, and mistaking the one for the other. As it will require no uncommon share of judgment and impartiality in the writer, to adhere stricily to the true characters and manners of the persons of his drama, while he allows his fancy free scope in forming the incidents of the narrative; so it will be necessary for the reader to exercise perpetual caution, that he be not led to entertain ideas of persons and events which have no foundation in history: and the apprehension of this will, in a great measure, prevent the effect which the work is designed to produce. It will perhaps tend more to ob, struct the natural operation of just sentiments and passions in the mind of the reader, than all the writer's powers of genius and fancy can do to produce them.
For these reasons we cannot but be of opinion, that our Author would have been more likely to accomplish the end with which he professes to write, by adhering to the character of an historian, and relating real facts, than by following his fancy into the regions of fiction and romance. This remark is, however, by no means offered with a view to depreciate the merit of this work; which bears such evident marks of superior genius and original invention, is written in a style so truly elegant and rhetorical, and above all is enriched with such'a variety of just and manly sentiments, and breathes so liberal and catholic a spirit, that it cannot fail of being read with approbation by all judges of good writing, and obtaining the warmest applause from every true lover of liberty and friend of mankind,
The great object of this work the Author declares to be, to expose the horrid effects of fanaticism, and to bring into universal detestation, that spirit of intolerance and persecution, of hatred and vengeance, which men entertain in behalf of a Deity whom they suppose to be incensed, and whdse ministers they pretend to be ; to guard mankind against the artifices and fury of this fpirit, and to infuse into their minds those great principles of humanity and universal concord, those maxims of indulgence and love, which religion, in concert with nature, hath made the abridgment of her laws, and the effence of her morality.'-To this laudable and meritorious design every true friend
to human nature must wish success; in the execution of it, every one who merits the name of a man will heartily concur
The translation of this work is, on the whole, well executed.
• See, farther, the account of the original of this work, as a Fo. reign Article, in the Review for March, 1777, p. 216. E.
ART. IV. A Walk in and about the City of Canterbury, with many
Obferuations not to be found in any Description hitherto published.
10 s. 6 d.
which is now before us, induced us to pass over this work, at its first publication, with only a flight notice. This fecond edition has, however, received the lait hand of its worthy Writer, who died while it was in the press; and it is but an act of justice to declare, that though from the confined nature of the fubject, Mr. G.'s book may seem dry, and tediously minute, to those who are unacquainted with the city, and the feveral objects described; yet it contains many incidental parsages, which, while they fhew the extensiveness of the Author's knowledge, will occasionally enliven the narration, even to the general reader.
Canterbury is a city of great antiquity; and, as the Author collects from the variety of British and Roman remains, was probably a place of confequence at the time of Cæsar's arrival in this ifland. From its metropolitical dignity, the cathedral is a rich fund of investigation for the student in ecclesiastical antiquities; and we intend no cenfure on the industrious inquiries of Mr. Goftling, when we add that he has made the most of them. This part of his Walk, becomes the more interest. ing, by calling to our remembrance che inanner in which our cathedrals were stripped at the Reformation, and the brutal savages made in them by the ignorant zealots of the last age.
Among the ancient treasures of this cathedral, or more properly the baits that drew treasures to it, were the bodies of St. Dunftan, and St. Thomas Becket; concerning which Mr. Goftling gives us the following anecdotes :
• Near the high altar was that of St. Dunftan, whose body was had in such high account by Archbishop Lanfranc, that he removed it hither with great folemnity from its firft sepulchre when he newbuilt the church. It seems fated nor to have lain long undisturbed in one place. He died about the year 988, and Lanfranc's coming hither was about 1070 : when the fire happened in 1174, his remains were again removed with those of St. Alphage, to the altar of the Holy Cross in the nave of the church; and after being newly