84 



THE CIVIL ENGINEER AND ARCHITECT'S JOURNAL. 



[March' 



short, by the erection of a complete wooden bridie, wliicli took olTa large 

 portion cl" the strain upon the chains. If the citaius had been wholly re- 

 Dioveii, the substructure would have been njore eilcclive; but as they were 

 allowed to remain, wilh the view of assisting, they still partake of these 

 changes in the form of the curve consequent upon the ur.ei|Ual distribution 

 of the weijihl, and eventually destroyed all the connections of the wooden 

 frantework uuderneatli the pbitfurni, and even loosened and fiuspended 

 many of the piles upon which the framework rested, and to which it was 

 attached. 



" The study of these and other circumstances connected wilh the Stock- 

 ton-bridge lead me to reject all idea of deriving aid from cliauis employed 

 in the ordinary manner. 



'• 1 have therefore turned my attention to other modes of employing them 

 in tonjunclion with the wrought. iron tube (as suggested by .'.Ir. Hud^kiu- 

 Bon), if such should be found necessary upon further investigation. 



" .is I have already staled in this I perceive no diHiculty v^liatcver ; in- 

 deed there is no either construction which has occurred to nie which pre- 

 sents such facilities as the rectangular tube for such a con.binalinn, 



" Having, I trust, clearly explained my views in reference to this im- 

 portant work, I have only to add that in two months I expect every ar- 

 rangement will be completed for commencing the masonry, which shall be 

 conducted w.th 'lie utmost activity and vigour. 



" I can scarcity venture to say, until after these arrangements are finally 

 roinpletetj', at what period we may calculate upon the cunipietiou of this 

 bridge; but I cannot recouinieud you tu calculate upuu llie whole being 

 Mccuiuplished iu le.ss than two years and a half." 



WEIRS ACROS.S RIVEKS. 



Report bij the Committee of the Clyde Triittsts o<t the Weir Question. 



The Committee believe the present position of the Clyde Trustees, as 

 regarda the question of Uie weir proposed to be er*^cted across the Clyde, 

 is as follow".' : — From ihr Act procured last Session of Parliament by the 

 Bridge Trustees, coulainiug clauses to the following effect ; 



1. 'J'hat the ISridge Trustees are entilled to form a new dam or weir at 

 or about one huiidred and forty yards above Hutch'json's Bridge, having 

 a lock or work therein, or connected therewith, at the expense of the 

 Clyde Trustees. 



2. When these works are erected, the Bridge Trustees are then au- 

 thorised to remove the weir or works placed at the Stockwcil Street Bridge 

 by tlie Clyde Trustees, at the Clyde Truslees' expense 



S. The Clyde Trustees are obliged to contribute a sum towards sinking 

 and building the piers and foundations of the new Bridge at Slockweli 

 Street. And the Clyde Trustees are obliged to maintain the weir and lock 

 constructed by the Bridge Trustees, at their expense, in all lime coming. 

 No detailed plans or estimates exist of the weir and lock. The Act pro- 

 vides that the cost to the Clyde Trustees, of the whole works for which 

 they are made liable, shall be fixed by two Engineers or Arbiters appoint- 

 ed by the .SherilT. 



Whether the Clyde Trustees ought to conlribule to the building of a 

 Bridge over the Clyde, is not within the remit to this Committee; and 

 having stated the present position of the Clyde Trustees as regards the 

 weir, the Committee proceed lo the consideraton of the clfect of the pro- 

 posed dam or weir upon the navigation of the Clyde. 



The Committee believe that all Engineers now act upon the principle 

 of giving the greatest possible freedom of admission to the tidal waiers, 

 as the best means of improving navigable rivers, — tiie recession of these 

 waters carrying down with them lo the sea, the alluvial matter held in 

 suspense by the waters of the river; and iu proportion to the quantity 

 and velocity of the retiring tidal wave, is the benefit derived from its 

 cleansing and deepening power. 



In order to carry out this principle, now well understood and universally 

 acted upon, Engineers widen, siiaighten and deepen the channel of rivers, 

 from the sea upwards, as far as the tidal wave can be enticed to come, 

 and break up and remove all obstacles lo its progress, whether natural or 

 artificial. The tidal wave in the Clyde, according to the report of the laic 

 Mr. M'Quiston, confirmed by subsequent observation, can be made to 

 How seven miles above the Cily of Glasgow, and give an additional pres- 

 sure and impetus to the retiring tidal wave of not less than eighty-millions 

 of cubic feet of water at ordinary tides; and if tiie river be properly 

 deepened, even this quantity of water may be increased. The Committee 

 Ihi-refore take leave to recommend that no weir or dam be erected across 

 the Clyde within the reach of the tidal flow. 



The Trustees are aware Ihat the largest portion of their stated oiiilay is 

 upon dredging in the River and Harbour; and the Committee are satis- 

 fied that a vrry large proportion of this outlay might be saved by the em- 

 ployment of the powerful natural agency of the lid^l waters. The ex- 

 pense of dredging from .July, 1S40, to .Inly, Itj'.-l, amounted to a very 

 large sum, and it constitutes by much the largest item of our annual ex- 

 penditure. The heaviest portion of this expenditure was ujion the Ilar- 

 huur, where dredging is performed at great inconvenience to the shipping, 

 and to tlie business of the i'ort. Nor will it in the opinion of the Com- 

 mittee, ever be otherwise, until the River above be cleaned and d, epened, 

 and a body of water procured suliicient to scour the Harbour, which at 

 preseut serves as a settling pool fur the upper waters. 



It will be said that the Clyde Trustees have no power nnder their Act* 

 to operate upon the River to the eastward of Stockwell Street Bridge, and 

 that their Acts bind them to maintain the present level of the River. 



The Committee believe that if the Clyde Trustees can show that the 

 Navigation of the Clyde is to be benefited by an extension of their powers, 

 say for seven miles above the Slockweli Street Bridge, penetrating into the 

 heart of the mineral districts, I'arliament will grant these powers ; nnd in 

 regard to their obligations to maintain the present level of the River to 

 the east of .Stockwell Bridge, for the protection of certain public works, 

 the Committee believe that the Clyde Trustees were coerced into the ad- 

 mission of these clauses into their Bill, and that there are other and better 

 modes of protecting these worlcs than by a weir across the Clyde. The 

 Committee refer to the analogous circumstances and condition of similar 

 works along the course of the River, beneath the .Stockwell Sireet Bridge, 

 because, if a like protection to these public works had been sustained, 

 there could have been no deepening or imp I'ovenient of the Clyde Naviga- 

 tion. The Committee, in short, believe, that no public companies, whetlier 

 constituted by Act of Parliament as Canal Companies, or Water Com- 

 panies, Joint .Stock Companies, or private individuals having works on the 

 banks of a navigable river, using its waters, or having a right of access 

 thereto, can for their interests control or prevent the impiovement of a 

 public navigable river, as far as the tidal flow reaches. 



From the absence of all detailed plans or descriptions of the works to 

 be erected at the weir, the Committee can give the Trustees no information 

 as to the height or elrralion of the intended weir; but from its containing or 

 being connected with a lock, the committee rre led to believe that the weir 

 or dam must be elevated to si/c/i a height as to enable the lock to lie wrought 

 at all times of the tido, and in all conditions of the river, or it i . eiiileni it 

 must be useless for navigation purposes. The Committee cannot believe 

 that so bold and iujurioas a measure as the elevation of the chanu'. 1 of the 

 Clyde would be attempted, although there is an indic:-.tion of such on in- 

 tention on the very small plan submitted lo Parliament ; and without such 

 elevation, the works describe,- appear to the Committee to be either useirs* 

 or impraclit ible. 



The C'omi. itltee, therefore, tr.ke leave to recommend that the Clyde 

 Trustees apply to Parliriment next SesJoG for powers to open up the na- 

 vigation of the Clyde lo a distance of fay seven miles above Ihe City of 

 Glasgow, to construct all necessary wQri>s, and levy such dues as shall 

 he judged iitting and proper. They will thus, in the opinion of the Com- 

 mittee, give great facility for the conveyance of minerals, country produce, 

 and traffic of every description to and from the Harbour; and v\hatisof 

 equal, if not of greater importance, they will, by the reressiou of the tidal 

 waters, be enabled to k'ep the whole channel of the river clear at a very 

 moderate expense, and thereby be enabled to devote several thousands, 

 a year, now expended in dredging the River and Harbour, to other 

 purposes. 



The Committee farther recommend that the Clyde Trustees intimate to 

 the Bridge Trustees their intention of going to Parliament next Session, in 

 order to prevent the Bridge Trustees from conslriicling a weir across the 

 River Clyde, w ilh a lock or works therein, and lliat the Bridge Trustees, 

 in the erection of their Bridge, do not in the meantime interfere with the 

 bed of the River, so as to prejudice the Clyde Trustees in their position as 

 regards the AVater Company and other parties. 



Before concluding their Report, the Committee also beg lo direct the at- 

 tention of the Trustees to what is already partially before the Trustees, 

 viz. — the attempt upon the part of a Canal Company, to take possession of 

 the River Cljde at and above the proposed new weir at Hutcheson's 

 Bridge, and to make additional works in connection vvilli (hat weir. The 

 Commitiee have not been able to procure a sight of the jdans of the works 

 which the Canal Company propose to attach to the weir; but as the w-hole 

 scheme implies the existence and continuance of a weir across the Clyde, 

 the Committee trust the Clyde Trustees will not be consenting parties to 

 any such scheme, but will oppose it with all their ])owerand interest, and 

 compel the Canal Company to terminate their works withiu the northern 

 line of high water. 



And the Committee fartlier recommend that a copy of this Report be 

 sent to the Lords of the Admiralty, and another copy to the Tidal Har- 

 bour Commissiouers. 



Archd. M'Li;llan, Cottrencr of Commitlei. 



PROCEEDirTGS OP SCIENTIFIC SOCIETISS. 



INSTITUTE OF BRITISH AKCIIITECIS. 



January 2C. — J. B. Papwoetb, V.P., in the Chair. 



The Very Rev. \V. Buckland, D.D., was elected an Honorary Member, and 

 F. C. Penrose, Esq., an Associate. 



A letter was read from Herr Zanth (honorary and corresponding member of 

 the Institute), at Stutg.ird, descriptive of a Ca-iino, now nearly completed 

 from his design and under his siiperintemlence, for tiie King of Wirtemburi.'. 

 The structure— named after the royal owner, " Wilhelma," is of stone, in 

 the Moresque style, the courses of the masonry being coloured white, 

 yellow, and red violet, and covered with copper, partly gilt. It is situated 

 in a winter garden, in the midst of four conservatories with pnnieoes, steps 

 and terraces, and parterres;— it consists of a vestibule, an Oriental court. 



