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je C (- e ,n creased the width of the bridge by means of a pro-towards the water.

: c arp „ ie t soffits of the different arches in this bridge, wereU “V turned in Portland-stone.

“y turned in Portland-stone. Over this, another archin* 0rrne< J of Purbeck-stone, well bonded with the preced-ar cl'i 80 arran S e d as to make the thickness of the doubles Parul ° Ut ^ le haunches four times that at the crown. Then rch le i® were constructed with barrel and intermediates ° as to maintain the edifice in equilibrio.

I Unin t len London Bridge was taken down, and a moreof o' err upted outfall was thus afforded to the stream, the bed; d 4t j e Thames became considerably deepened, and the foun-c °tlat 3 ^ le different bridges, which had been previouslyll r i ( j ru oted, were thereby more or less affected. Westminstertli e suffered particularly from that cause; for, owing to

tii^’^'y insecure substructure on which it was founded, its

;

h av .

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e been gradually giving way for years ; and, in con-u, e :riae of the inequality of yielding which has taken place,It e ntire bridge became in a deplorably dilapidated condition.°fth deemed absolutely necessary to prop up several; 6 fid 8 ar ches by centerings, to remove the weight over others,1 'ffisi 01 'der to prevent a too manifest appearance of thetli(. f. ll; 'y breaks which have taken place in the roadway,0tle balustrade has been replaced by a temporary wooden

Parapet. -To our thinking, the repairs which it has

In Un dergone, were effected in a most injudicious manner.5t cli 6 dfst place, the system of propping up some of the<li C i a j S ’ a ud allowing others to sink freely, was highly preju-ity. to tbe stability of the bridge ; and indeed one of the

PortP vvas only partially supported, so that the remainingseparated from it, and sunk several inches, to theA* a j n ent peril both of its real and apparent efficiency,a *•’ *'I' e uselessness of facing the piers with new stone,when the entire demolition of the structure becamea ble, must be evident to every one who will give the

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but

a passing consideration.

As -

'id a ’| '°wever, this bridge will be taken down very shortly,^ hot lan< - 80me mo d ern structure will supply its place, wep res 'biink it necessary to say more on this subject atnt t,m e.

'UjlK*

fn point of date among the stone bridges of the18 that of Blackfriars, which was commenced in the?ffi>;» and finished in 1770, by Robert Mylne , a Scotchwho had just before returned from Rome, where he

‘"tties,

. i elU ( j <ien pursuing his studies, and where he had earned at 0 r tl ^Served reputation ; having received a silver medal

coins of George the Second, in the foundations of

til jcpuidkiuu ) lctcivcu a SUVCl ILICUcll

-vej, i e Roman Academy, which he deposited together with•he v. . c ‘ ! " ~ ‘ ~ '.

jSitt 4 ? friars Bridge is about 1,000 feet in length, and>o ,, a - d Ret wide, including a carriage-way of 28 feet, and* buii t Se ^ ^ 00t P at; bs for pedestrians, each 7 feet in width ; itN.. e °i' nine nearly semi-elliptical arches, of which the

a „° ne I® 100 feet, and the others decrease in span, as

W, ar e r’

Hi,

v sly placed nearer the banks of the river, being respec-Jsre j > ^3, 83, and 70 feet, by which it will be seen thati 8 a ^ater-way of 788 feet in the clear. The road-cl e a uniform curve, being the segment of a very large

\

e at (- a ^ c I'b e cture of this bridge is exceedingly beautiful, andr - ril. e IS disDlaved in the desicti 1 the bavs over each of

pi ers '“ 18 displayed in the desigh ; the bays over each of8 f ac supported by Ionic columns, which give a lighti*-' 8 to t ^ character to this really handsome edifice ; andls c<l a „„ e regretted, that the materials of which it is com-

^ unit tuc luaicnuis ui v>unyii it, 13 wiu-

li ? e d r 80 perishable a nature. In consequence of thet * ie entablature of the columns is not made

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6 u

and the consequent inequality in the height

of the columns, is a marked defect in an msthetic point ofview. The parapets of this bridge are formed by a veryhandsome stone balustrade, 4 feet 10 inches in height; sothat, while the security of persons passing over the bridge isamply assured, the view both up and down the river is unin-terrupted. The expense of constructing Blackfriars Bridgeamounted to £152,840.

The plan of forming the foundations by means of caissons,was unfortunately again resorted to in this case, and althoughshort piles were driven into the bed of the river on whichthe bottoms of the caissons were made to rest, still thescouring process to which the channel of the Thames hasbeen subjected of late years, has seriously affected the stabilityof the piers, and the change which has consequently takenplace in the form of some of the arches, plainly point out thenecessity of constructing a new bridge for this reach of theriver at no very distant period.

Waterloo Bridge is one of the finest stone bridges con-structed over the Thames ; its bold, solid style of architec-ture being admirably suited to the character of a bridge overa large and important river, where massiveness and strength,combined with taste in design, have been judiciously andpleasingly combined; and when to these considerations areadded the circumstance of its having a roadway perfectlylevel throughout, we may safely come to the conclusion, thatit is one of the most successful specimens of bridge-buildingwhich has ever been produced. The celebrated Canova wasloud in its praises, and extolled it as the beau-ideal of suchconstructions.

It was built by the late eminent engineer Rennie, whosubmitted two plans, one with seven arches, and the othernine ; the latter was adopted, and the first stone of the newstructure was laid in the October of 1811. The foundationshe formed by means of coffer-dams, composed of three rows ofpiles one within the other, at a distance of about 3^ feetbetween the rows; the intermediate spaces having beencarefully filled in with well-rammed clay. The water wasthen pumped out of the coffer-dam, and piles a foot square,and about 20 feet long, were driven into the bed of the river.A framework of timber was then constructed on the top ofthose piles, and the spaces- between the pile-heads, to adepth of about a foot and a half, were filled in with stonestightly packed, and well grouted with liquid mortar. A floorof beech-planking, six inches in thickness, was bolted to thetimber framework, on which the masonry of the piers andabutments was then commenced.

The entire surface-work of this bridge was built of Corn-ish granite, and the interior consists principally of Craigleithsandstone, well bonded, and cemented by a grouting of mor-tar. The spandrels of the arches were left hollow, to avoidan undue loading of the haunches, with the exception of sixtransverse brick-walls, for the purpose of' supporting theroadway.

All the arches of the bridge are the same—semi-ellipticalin form, 120 feet in span, and having a rise or versine of35 feet. This allows a clear waterway of 1,080 feet. Thepiers are 87 feet long, from the extremity of one cut-waterto another; they are 30 feet in width at the foundations, anddiminish to 20 feet at the springing of the arches. Overeach pier there is a rectangular recess, which is supportedby Doric pillars, these, together with an open stone balus-trade, give a certain degree of lightness to the edifice, with-out interfering with its characteristic solidity.

The entire length of Waterloo Bridge, including itsapproaches, which are built on land-arches, at either side ofthe river, is 2,456 feet.

This bridge took only six years to construct; and it was