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their advice and plans, &c. Here we
have a full account of the book, with a
flattering report of its principle and the
ory, its elegance, originality, &c. &c.
I have no objection, Sir, nor do I fuppofe
any liberal-minded man has any objec-
tion, to the compliments given to Mr.
Atwood, for his ingenuity and fcientific
labours, having deferved well of the pub.
lic on many occafions. But why fhould
one ingenious man be raifed by the de-
preffion of another? There is furely no
good reafon and yet we here find, the
latter is outraged by a most injurious and
deceptious comparison of the principles of
his theory, with that of the former. It
is impoffible to avoid perceiving, that
there exifts fome fecret and mysterious mo-
tive for fo much offenfive matter, very
different from what ought to actuate the
mind and influence the conduct of a fair
Whatever it
and judicious Reviewer.
may be, it certainly ought not to appear
in the writings of a Reviewer: whether it
be fome pique against any man in parti-
cular, or whether it arifes from a difpo-
fition in the gentlemen of Cambridge to
difcourage the productions of others; a
difpofition with which they have fome
times been charged, though perhaps un-
justly and illiberally. I here mentioned
Cambridge, because it is faid the mathe-
matical writer for the Monthly Review
is at prefent an ingenious young gentle-
man, refiding in that univerfity, of the
name of Woodhoufe: if I am mistaken
in this, I afk his pardon for the mention
of his name, and he will correct me by
Till then, in
difclaiming the concern.
common with many other perfons, he will
excule me for the belief, that he is the
Reviewer, whofe conduct in the alleged
inftance is fo much complained of.

Whatever be the concealed caufe, Sir,
whether one or both of thofe juft alluded
to, or whatever elfe, the fact appears moft
certain and evident. Unfortunately for Mr.
W. however, if he is the Reviewer, it has
carried him fo much away, in his eager
nefs to outrage Dr. Hutton, as to hurry
him into frange miftakes and overfights.
In the comparifon he makes between the
works of Dr. Hutton and Mr. Atwood, he
reprefents both their books as the fruit of
their refearches on the prefent occafion
How un
of the new projected bridge.
Dr. Hut-
fair, Sir, is this infinuation!
ton has objected to this mifreprefentation,
(Review for June, page 222), his tract
having been hadily compoted, on an-
other occafion, 30 years before.-Again,
Mr. W. had milieprefented Dr. Hut-

ton's theory, by forcing upon it a fup-
pofition, difclaimed by him, and unwar-
ranted by his book, namely, the use of
mortar or other cement, to form the arch
into one coherent folid mals: which Mr.
W. afterwards retracted.--In the
laft place, Mr. W. reprefents Dr. Hut-
ton's theory, as practically inaccurate,
In anfwer to
because it does not confider an arch as
made up of wedges.
which, Dr. Hutton replied, that he did
"confider the arch as made up of fec-
tions of wedges, and had pointed out
the direction of the joints: adding that
every writer on arches must confider
them as made up of fuch wedges; for
without thefe, there can be no fuch
thing as an arch." For, what are the
vouloirs, fo often mentioned in his book,
but another name for the arch-ftones, or
the wedge-like pieces which form the un-
der curve of the arch, over which is
raifed the whole of the upper or fuper-
incumbent wall, the vertical load or pref-
fure of which is thrown into the tangen-
tial direction of the faid curve, or
along the line of the faid vouloirs, by
means of the direction of the joins,
or butting ends of thele wedges, which
Dr. Hutton lays are always to be confi-
dered as cut perpendicular to the curve,
viz. under the article Vouffoir, page 104,
of his book. And yet Mr. W. afks,
"In what part of his work has Dr. Hut-
ton confidered the arch thus compofed."

Mr. W. thinks that Dr. Hutton's
theory will not apply when the arch is
formed of wedges, and fays, "it seems
that, whoever fhould adopt that theory,
without confidering the mode of applying
the weight and the forms of the wedges,
would be deluded by a speculative truth."
"If the arch be compofed of wedges,
fooner or later their properties must be
confidered." Hence we at length per-
ceive that Mr. W's objection to Dr.
Hutton's theory is, because it is not
founded on the mathematical mode in
which the wedge acts, when confidered
as one of the fimple mechanical powers.
Here then is the rock upon which Mr.
W. is wrecked, with his new theory, or
rather old one, which in reality it is,
having been long before treated of by
former authors: from thefe authors Mr.
Emerfon, after he had difcuffed the true
theory, in his Mifcellanies, introduces
one propofition, viz. the xith, page 170,
on this principle, with the view to con-
demn it, which he very justly does in
pages 171 and 173. In fact that old-
new theory, fo violently contended for by

Mr.

Mr. W. can have no place in the practice of arch-building, because that here the arch-ftones cannot act as true mathematical wedges. For in thefe, it is well known that they are retained in their places, or have their weight, and other force acting on their back, balanced by two forces acting perpendicularly against their fides, which are conceived to be perfectly fmcoth or polished. But will Mr. W. fay that this is the cafe with the vouloirs or wedges of a ftone arch? Are their fides polished, or quite void of all friction? On the contrary, does not every builder know that their butting fides are fo rough, as by their friction on one fide only, in many cafes, to be prevented from defcending down in the direction of the joint? For who is there that knows not that a flat-ftone can be laid on a furface confiderably raised or inclined to the horizon, as an inclined plane, without fliding down, being retained in that fituation by the roughness of the surfaces, without any other wedge or force above it to retain it, in the manner of the mathematical wedge. Is it not with justice then, that fuch a theory of arches has been long fince exploded, and another, more confonant to the principles of matter, substituted in its ftead?

After all, Mr. W. in the rapid flow of his declamation, infinuates, in Dr. Hutton's theory, the want of experimental proofs and mathematical demonftrations. But furely no candid reader can complain that the theory is not fufficiently demonftrated in his book. And as to experimental proofs, Mr. W. might have known, that thefe have not been wanting; practical experiments having been made on that theory with complete fuccefs.

Royal Military Academy, Woolwich, July 24, 1802.

CHARLES HUTTON.

To the Editor of the Monthly Magazine.

SIR,

MONG your Literary and Philofo

is added, the experiment has not been at tempted in this country, but the invention itself was made the subject of a very formal notice to the House of Peers, without, however, producing a very grave effect upon that affembly. Whatever might be the motive operating on the majority of the individuals compofing that houfe, to regard with indifference the communication of Lord Stanhope relative to this fubject, I am certain that, to those who are acquainted with the principles of hydrostatics, and the various improvements that have been, from time to time, made on the inftruments employed for the purpofes of diving, the notice of that profound philofopher will appear in a very different point of view.

It seems uncertain, at what period the diving-bell was first invented. Mr. Boyle relates, on the authority of others, that Cornelius Drebell, during the reign of James the First, contrived not only a veffel to be rowed under water, but also a fluid to be carried in that vessel, which could fupply the want of fresh air, and that a fub-marine voyage was actually made in it by feveral perfons in the river Thames. But, whatever degree of credit may be given to the evidence respecting this fact, it is, however, certain, that the diving-bell has been long known, although it unquestionably remained in a very imperfect ftate, until improved by the celebrated Dr. Halley. The principal defect of the original diving-bell was, that it contained but four or five hogfheads of air, which, before it could defcend to a great depth, would be compreffed into one, by the weight of the fuper-incumbent water. Now, as, from repeated experiments, one man is found to require about a gallon of fresh air to fupport refpiration every minute, and as, befides, in this inftrument, candles were neceffarily employed, which also very much tend to confume or vitiate the air, it evidently follows that two or three men, with a couple of candles, could not remain in it with fafety for a fufficient

Aphic Varieties for a month, you length of time to perform any ufeful la

mention that Mr. Fulton, an American, pretends lately to have difcovered a method of navigating veffels at any depth under water, and of enabling the perfons who navigate them to continue inimeried for feven hours without the accefs of fresh air; this invention he intends to apply, it is fericufly afferted, to the purposes of warfare, and, from his ability to approach veffels unfeen in a state of fecurity, he propofes to blow men of war to atoms. It

bour. To obviate thefe defects, Dr. Halley fixed in the top of his bell a piece of ftrong clear glass to convey light from above, and a cock to allow the escape of the vitiated air. The divers were fupplied with fresh air by means of two barrels which alternately rofe and fell like two buckets, and as the cold air from the barrel flowed into the bell, it expelled the hot foul air through the cock at the top of the machine; by which means fuch a

plentiful

plentiful fupply of fresh air was communicated, that Dr. Halley himself with four companions remained underneath ten fathoms of water for about an hour and a half, without experiencing the least inconvenience. Other improvements have fince been made on this bell by a Swedish engineer, whofe name, at prefent, I do not recollect; but the diving-cheft of Mr. Smeaton would appear to poffefs advantages which render it fuperior to every other machine hitherto employed in this country for fimilar purpofes; one of its peculiar excellencies is, that the divers are fupplied with a conftant influx of air, by means of a forcing air-pump, in a boat on the furface of the water.

The fate of Mr. Day, which was, doubtlefs, occafioned by his ignorance of hydroftatical principles, and that of the late ingenious Mr. Spalding, who had contributed much towards the improvement of the diving-bell, and who fell a facrifice to the negligence of his attendants, at the Kith Bank, in Ireland, as well as fimilar accidents, seem for a time, to have repreffed the fpirit of enterprise in this country. In America, however, fo early as 1776, a very ingenious diving. machine, or fub-marine veffel, was conftructed by a Mr. Bullinell, of "Connecticut, of fuch a fize as to contain the diver, and air fufficient to fupport him thirty minutes without receiving any additional fupply from above. At the bottom of this boat, oppofite to the entrance, was fixed a quantity of lead for ballaft; at one edge, which was exactly before the diver, who fat upright, was an car for rowing forward or backward, and at the other edge, a rudder for fteering. An aperture at the bottom, with its valve, was intended to admit water for the purpose of defcending; and two brafs forcing-pumps ferved to eject the water from within, when neceffary for afcending. At the top was likewife an oar for the purpofe either of afcending, defcending, or continuing at any particular depth; a water-gauge, or barometer, determined the depth of the defcent; a compafs directed the course, and a ventilator within fupplied the veffel with fresh air, when on the furface. Behind this fubmarine vessel was a place above the rudder for carrying a magazine containing fifty pounds of powder, with the apparatus uled in firing it, conftructed in fuch a manner as to run any propofed length of time under twelve hours, when it un pinioned a strong lock, (resembling that

of a gun), which gave fire to the powder. This apparatus was fo pinioned that it could not poffibly move, till, by cafting off the magazine from the veffel, it was fet in motion. For a more particular defcription of this veffel, see the last volume of the Tranfactions of the American Philofophical Society, or the 35th volume of the Repertory of Arts.

Some experiments, which were made at Connecticut, fufficiently evince the nature and ufes of this fub-marine veffel, and that it did not afterwards prove deftructive to a number of the British veffels, near Governor's Ifland, and in Hudson's River, is not afcribable to any defect, either in its principle or construction, but to fome extraneous circumstances, which it would be here wholly unnecessary to relate.

Mr. Bushnell's invention, whilst it deprives Mr. Fulton of every claim to be confidered as the original discoverer, at the fame time fufficiently shows to what a degree of perfection fub-marine navigation may be carried. The recent difcoveries in chemistry, particularly that of Dr. Priestley, by which oxygen, the only refpirable portion of the atmosphere, can be obtained, in such abundance, from various metallic oxyds, as manganese, ininiums, &c. might, perhaps, be fuccelsfully applied to the ftill farther improvement of this art; if, indeed, any mode could be discovered of difengaging the vital air from these bodies, without the aid of heat, it feems highly probable that various fub-marine projects might be undertaken without even the neceffity of rifing occafionally to the furface of the water, and with, perhaps, lefs risk from accident, than in the usual mode of navigation.

When, at the conclufion of a ten year' difaftrous war, we find a military tyranny eftablished in the heart of Europe, the dif tinguishing feature of which is characterized by a defire to deprefs this country, the only power that can now effectually oppofe any barrier to whatever ambitious fchemes fuch a government may conceive; is it prudent to disregard the warning voice of philofophy, and to view, with the apathy of ignorance, the improvement of an art, capable of being employed for the molt deftructive purposes of warfare, and against which, in the unfortunate event of a new rupture, neither the most diftin guished valour, nor the greatest skill in naval tactics, could prove of the leaft avail.

If the brief sketch, which is here given, of

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fketch.

At the period of my communication alluded to, hoftilities had not cealed: though the war-whoop, that fo long refounded throughout Europe, had in fome degree fubfided, the furious conflict it had excited, ftill continued. Happily for the country, and to the confolation of humanity, the fword has been fince fheath ed; and, even in thefe parts, where an oppafite intereft may be fuppofed to pre

vail, fuch was the nature of the event that it was hailed with joy and general. fatisfaction. In this altered ftate of things, I have to give an account of Golport.

Its diftance from Portsmouth, acrofs the water, is about a mile. The ufual points of communication, on the Portfmouth fide, are the place, to a part of which the late defcription of your correfpondent, Mr. Stevens, must have added fome celebrity, and the Hard of Portica. The communication is kept up by wherries, to the number of feveral hundreds, a large proportion of which is conttantly plying. The intercourfe between the towns is confiderable, as will be prefumed from thefe circumftances; and, excepting periods like the prefent, when the pay ng-off the fhips increases it beyond the ufual Imits, it is greater in war than in peace. The diftance from Gofport round to Portsmouth by land, is about thirteen niles, fomewhat within which compaís les our harbour. The town is fituated

However true the account of Mr. Stevens may be in part, the connivance he fraks of is an affertion, I apprehend, unwarranted by facts. To make me fay what his letter has endeavoured to do, is, I muft confefs, rather extraordinary, and unfair dealing even with an adverfaty. MONTHLY Mae, No. 90.

in the parish of Alverftoke, is totally dif tinct from Portsmouth, and, not being an exclufive jurifdiction, is under the general magiftracy of the county. It has, however, its Bridewell, its refident justice, and its police-office.

On entering the town by the principal gate, or on landing at the beach, a ftranger is not likely to be highly prepoffeffed in its favour by firft appearances. The gate on the of two adjoining arches, erected in the line of the new ramparts; but it is fuch a heavy congeftion of brick and earth, and fo devoid of all architectural beauty and ornament, that, on ap lancholy, and filled with as much gloom, proaching it, the mind is moved to meas if entering a fepulchre or a dungeon. The vifitor by water will have equal, if not greater, reafon to be diffatisfied. He is no fooner landed than his attention will, moft probably, be ftruck by the dirty and neglected ftate of the Hard; with the female objects of infamy and difguft that loiter on the beach, and the long range of alehoufes that present to his view their deCorated and emblazoned fronts, whofe dangling figns and fign-boards protruded cumftance throughout the town, giving it to fome yards diftance, a common cirthe most flatternly and diforderly appearance, cannot well be paffed unnoticed. Having glanced over this motley and evervarying fcene, we will haften on to other parts of the town.

"Tis here in diff'rent paths the way divides;""

The right leads through North-ftreet to a fpacious square, which is the court-end of the town, the parade, the mall, and altogether a very pleafant place, having a fine, open, and interefting view of the harbour, the dock-yard, the shipping, and the country beyond. The left leads through South ftreet-a difmal avenue, crowded with alehoufes, gin-fhops, pawn-fhops, and hops of a itill worfe defcription, and the utual inhabitants and cuftomers of fuch places of entertainment and refort in a fea port town-to the gaol, the policeoffice, the old poor houte, the walls and batteries erecting by the convicts, to Haflar Hofpital, and the Gibbets.

It is

Between these two streets, in a parallel direction, runs the High street. commodious in breadth, and in length The upwards of a quarter of a mile. houfes are, in general, tolerably good, or fuch as commonly compofe the principal ftreets of towns of the fame extent under ordinary circumstances. In the centre of the road ftands the market-houfe; but it Ε

is

is an old wooden edifice, and though its front is fet out with a ftatue, the building is certainly no ornament to the place. It is, therefore, I understand, to be taken down, and another is to be built in a more convenient fituation. At the western termination of this ftreet are the ramparts forming the line of fortification on the land fide, which has lately been extended beyond the old walls, part of which has been rafed, together with the old north gate; but the line is not yet complete. By this alteration Weevil brewery and cooperage, belonging to government, are added to the town, as also a confiderable area of ground, and on part of this space temporary barracks have been erected. The ramparts are a fashionable and much frequented promenade, and the profpects they afford are extenfive and not deficient either in grandeur or in beauty. They command various views of Spithead and the Isle of Wight, the Offing, and the coaft of Suffex; and, in the oppofite direction, Portsmouth Harbour and the adjacent country; bounded on the north by Portfdown, a lofty and entire range of chalky hill, ftretching from east to weft, from the delightful little village of Bedhampton to the town of Fareham, a dif tance of between seven or eight miles; and though in itfelf fomewhat dull and monotonous, from the uniform and continued fweep of its outline, it is certainly no unimportant object. It at least forms an excellent back ground to the picture of our harbour, and, what is far more material, is an admirable fcreen to it against the violent storms from the north. Such pro fpects cannot be viewed by obfervers in general without pleasure, nor can they well fail in fatisfying the eye of the molt faftidious. Finely diverfified with fea and land, with thipping and rural scenery, connected as they are with fubjects of great national import, and martial deeds of high achievement, they may not be unworthy either of the painter's or the poet's notice. That they are capable of filling the mind with rapture, or of elevating it to fublimity, is a point that must be left to the oblerver's own deciñon.

It ought not, however, to be underftood that thefe views belong exclufively to the town I am defcribing: they are common to the vicinity; and there are fituations, apart from Gofport, where they may be enjoyed with till greater perfection than on thefe ramparts. For extenfive profpects and bird's-eye views af Gofport, Portfimouth, &c. no fpots better chofen than the Down al

ready mentioned, and the Tower of Port mouth-church; but even these are not the places to be preferred, unless for the purpose of obtaining an entire view of the town, the coalt, and the neighbouring country. Elevated as thefe points are, objects that would otherwife intereft us, are too much diminished, when viewed from them, to imprefs us with their proper effect; and from the Down, in particular, the country appears as a perfect flat, fwampy and even fubject to inundation-still, however, the profpects from hence are warmly admired, and hold no inferior rank in general eftimation. But points of view far above the scene, or where one is perfectly isolated, are, I think, in regard at least to thele parts, fomewhat objectionable. But, to return to Gofport Ramparts. tance and near the beach, that communicates directly with Spithead, is the Navalestablishment of Hallar-holpital, a grand and extenfive building, and in every refpect adapted to its purpofe. Contiguous, is a new range of houies that have been erected on part of the cemetery, for a governor and other officers. Near the hofpital are fome newly-erected permanent barracks; and in a different direction without the town is the new Militaryhospital, another extenfive and magnificent edifice. The parish-church is at the diftance of about a mile and a half from the town, in the pleafant village of Alverstoke.

At a fhort dif

The new poor-houfe ftands about midway between the town and the church, on a very eligible spot. It is a stately edɩfice; built upon a very liberal plan, not altogether free perhaps from the charge alleged against it of prodigality. It is highly commodious, and large enough to contain half the parish, should the expence of erecting it, and the approaching badnefs of the times, fucceed in procuring it fo great a number of occupiers. In the town is a chapel of eafe, with a perfonage-houfe. The diffenters meetinghouse, the Catholic-chapel, and a new theatre, complete the lift of public-buildings, which Gofport boats. of these being without the ramparts, the

The chief

* As an expedient to ease the parish of exPence, and at the fame time to people this goodly manfion, fo pleasantly fituated in the country, I would propofe that the wings fhould be furnished, and let out as lodginghoufes, to the inhabitants, under a politive agreement, however, to quit, and remove to another part of the house, so foon as they become chargeable.

appear.

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