BRIDGE. 



485 



utmui- 

 irr briiljo. 



In 17:18, the situation was finally determined to be a 

 little waybi'lmv New Palace Yard; the model made by 

 M. Labalve was approved of, and lie was appointed 

 engineer. The intention at this time was to construct 

 the piers of stone, and place a wooden superstructure 

 upon them. This latter parj was designed by Mr James 

 King, who contracted to complete it in 12 months 

 after the piers were finished for 28,000. 



It was not till after many explanations and discos- 

 sions, that Mr Labalye satisfied the commissioners, 

 appointed by parliament, of the facility, economy, 

 and security to be derived from laying the founda- 

 tions of the piers m caissons or chests, instead of pla- 

 cing them upon piles in the ancient manner, cut off 

 about the level of low water ; or using batterdeaux 

 or coffredams, formed around the foundations, and 

 pumping the water from the inside, as had been per- 

 formed in more modern times. This beautifully sim- 

 ple mode was, however, adopted, and the first stone 

 of this great fabric was laid by the Earl of Pem- 

 broke on the 29th January 1739. During the same 

 year, the commissioners directed Mr Labalye to pre- 

 pare a design for a superstructure of stone, which 

 he did, and it was approved of and adopted on the 

 Slst January 1740: A liberal arrangement having 

 been made with Mr King respecting his contract for 

 the wooden superstructure, he immediately designed, 

 for the stone arches, those excellent centres, which 

 have ever since served as a model for works of a si- 

 milar kind in England. 



The works were carried on with great dispatch 

 and success ; the centre of the last arch was struck 

 on the 25th July 17-17, and, on the 14th November, 

 the roads and streets were finished. A circumstance, 

 however, took place, which prevented the bridge from 

 being, at that time, opened to the public. The work- 

 men employed to get gravel out of the bed of the ri- 

 ver to cover the roadway of the bridge, finding some 

 very suitable near the third pier, on the western side 

 of the centre arch, they excavated considerably lower 

 than the foundation, and too near it ; the gravel then 

 run from under the platform, and the pier sunk so 

 inuch as to render it necessary to take down the two 

 arches which rested upon it. The securing the foun- 

 dation, rebuilding the pier and two arches, and repla- 

 cing the parapets, pavements, and roadway, was com- 

 pleted, and the bridge opened to the public on the 

 18th Nov. 1750. This bridge consists of 13 large 

 and two small arches ; their forms are semicircular ; 

 the middle one is 76 feet span, and the breadth over 

 the parapets 44 feet. See Plate LXXXVI. 



About 10 years after the completion of Westmin- 

 ster bridge, another was begun to be erected be- 

 tween it and London bridge, now well known by 

 ackfriars tne name o f Blackfriars. The design was made by 

 Robert Mylne. It consists of nine arches of an el- 

 liptical form ; the middle one is 100 feet spati, and 

 the breadth across the bridge is 43 feet 6 inches. Mr 

 Mylne benefited by the example of Labalye, and 

 built the piers in caissons ; but probably alarmed by 

 the sinking of one of the piers at Westminster, he 

 drove piles in the spaces upon which the bottoms of 

 the caissons are placed. His arches being of wider 

 span and of an elliptical form, 1 is piers of pn jmruoii- 

 ally less thickness, and having less masonry over 



the top of the arches, this bridge has a much lighter Bridgt. 

 appearance than that of UY It has been '-"'" ' 



doubted, whether the slender detached Ionic column* 

 at" a proper accompaniment to such a work, and 

 whether the divisions of the lengths of the rusticated 

 headers of the arches are any improvement. His cen- 

 ters are evidently a copy of those used at Westminster. 



The general style of this bridge bespeaks a mind 

 emboldened by the success of his predecessor, to ad- 

 vance, though very cautiously, a step further in the 

 practice of bridge-building. It is a work of great 

 merit, and will riot suffer by a comparison with any 

 other constructed in die same age. It was begun in 

 1760, and completed in 10]. years. See Plate Vi..\rt 

 LXXXVI. LXXXVi. 



At the same time that this noble work was carry- 

 ing on at Blackfriars, a very fine bridge was con- 

 structing upon the river Tay, at the town of Perth Bridge at 

 in Scotland. It consists of nine arches; the middle '' 

 one is 77 feet span, the width across is 26 feet, and 

 the total length is 906 feet. It wa designed and ex- 

 ecuted under the direction of Mr Smeaton, between 

 1760 and 1771. About the same time, and under the 

 direction of the same gentleman, a bridge of no in- 

 considerable magnitude was built over the river Tweed 

 at Coldstream, consisting of 5 arches, the middle one 

 being 64 feet span ; and also a bridge of seven arches Bridfjeovet 

 over the river North Esk, near Montrose. the E>k. 



Previous to forming the plan of that magnificent 

 extension of the city of Edinburgh, known by the 

 name of the New Town, it was necessary to form a 

 commodious communication with the central part of 

 the High Street of the Old Town. This was ac- 

 complished by constructing a bridge over the deep North 

 valley called the North Loch. This bridge consists bridge at 

 of three arches, each about 72 feet span, and two Edinburgh, 

 small arches each 20 feet span ; the height from the 

 present surface of the ground to the springing of the 

 arches on the piers, is 17ft. Gin. ; the arches being 

 semicircular, rise 36 feet, the archstones are 2ft. 9in., 

 and from the top of the archstones to the top of the 

 parapets, is 9ft. 9in., making the whole height, from 

 the surface of the ground to the top of the parapet 

 over the middle arch, 65 feet ; the breadth across 

 the sofBt of the arches is 42ft. 3 in. From the arches 

 to the banks on each side of the valley, the spaces are 

 occupied by coach houses, stables, &c. formed under 

 the roadway. The outline of the cornice and para- 

 pet, contrary to usual practice, is a curved line, bend- 

 ing downwards. This, in viewing the elevation, gives 

 the appearance of the middle part of the bridge ha- 

 ving sunk. Excepting the arches, which are fine 

 and well executed, no part of the design claims much 

 commendation ; and we cannot help regretting, that 

 the architect Mr Mylne, has failed in rendering this 

 structure a suitable feature to the singularly fine situ- 

 ation which it occupies. 



Several excellent stone bridges have lately been Bridges 

 constructed upon the river Thames at Kew, Maiden- over the 

 head, Henley, and Oxford ; and not inferior to these Thames & 

 are the bridges over the river Severn in Worcester- ' 

 shire and Shropshire. Five ot these were designed 

 and executed under the direction of Mr Gwynn, a 

 native of Shrewsbury, and two by our countryman 

 Mr Telford, the engineer. 



