164 



THE CIVIL ENGINEER AND ARCHITECTS JOURNAL. 



[April, 



some of those further improvements which it will be our duty hereafter to submit for the 

 approval of your Majesty and of Parliament. ..,„.,, j 



We have stated that tlie coal duties ot 8d. per ton in the Port of London are now 

 charged until the year I8IW. with the improvements already made or in progress. The 

 whole rate of duty upon this article, as now collected, is 13d. per ton ; viz. 8d. charged as 

 before !nBnlioned,-4d. received by the Corporation, in lieu of certain rights and interests, 

 —and Id also collected by them for compensation to be paid to individuals, and other 

 ex]ienses incidental to the coal market, on the occasion of the new regulation of the coal 



trade under the Act of lB:il. ■ j j . r , i . -n i. 



It is estimated that the charges upon the last- mentioned duty of Id. per ton will be 

 eTtinguished in about three years from the present time. 



Such beirie the existing state of these duties, it is our opinion that it may be advisalde 

 to augment the total rate of the tax collected from l:^d. to 18d. per ton ; making the du- 

 ration ol the wliultf contemporaneous witli that of tile duty of Hd. per ton, as above- 

 mentioned— excepting of course the duty of 4d. per ton belonging to the City of London, 

 which is permanent. By these means there would b« at tlie dispesal o- Parliament, for 

 Metropolitan improvements, and more immediately for that whicli is the subject of our 

 present consideration, the produce of a duty of ."id. per ton until the duty of Id. per ton, 

 appropriated to the coal market, is set free, and ot fid. per ton for the remainder of the 

 term. It is estimated that the annual amount would be, in the former case, jt'b-i,S7b, 

 and in the latter, .iti;.5.B,')l. 



We are anxious tliut your Majesty should be assured that we should not lightly recom. 

 mend even tliis comparjtivaly inconsider^ibie augmentation of local taxation, nor without 

 a careful consideration of the interests of that great community on which this aiditional 

 temporary burthen would be im|)Osed. We should not, indeed, venture to otfer this 

 suggestion except under thestrongest conviction that benetits much more than equivalent 

 to the sacrifices thus proposed would resrit from the adoption of the plans now submitted 

 for your J\laj.;sty's ap[)roval. The labours of successive committees of the House of 

 Commons who have puisued elaborate inquiries, and have expressed decided epinions on 

 the subject, have spared us the necessity of setting forth in detail the grounds upon 

 which we consider that an addition to the coal duties is (within certain limits) the most 

 equitable nu'l llie least burtliensume mode of providing for improvements of tins descrip- 

 tion ; and we tticrefoie cannot hesitate to recommend it as the best resource for the ac- 

 complishment of a measure having for its object to secure to the metropolis the advan- 

 tages of an improved and better regulated navigalior. of a great portion of the noble 

 river which flows through it ; and calculated at the same time to contribute largely to the 

 convenience, the recreation, and the health of its inhabitants. 



Appendix — Description of Mr. Walker's Plan (A.) 



This plan (A) proposes, as a final measure, — 



First, to bring the river Thames to a more uniform width than it is at present, 

 by means of embankments, in the lines shown on tlie accompanying plan. 

 Secontily, to improve the present river lines where the ground is nut built 

 upon, by easing tlie present quick curves. Thirdly, to remove the shoals by 

 dredging, and to form the bottom of the navigable channel to a regular 

 line, (Plate VI. Figure 1,) the excavated material being applicable to filling 

 in behind the embankments, and thus to form quays at the level of 

 3 feet 6 inches or 4 feet above high water. Trinity standard. These 

 quays to he, upon terms to be settled, the private property of the 

 parties owning the present wharfs, of wliich they may be considered as 

 an extension. Fourthly, to continue the covered sewers out to the 

 front of the proposed embankment, where they may discbarge below the 

 level of low w,ater. Fifthly, to avoid the heavy claims that might be made 

 for interference with the coal and timber merchants, if a solid embankment 

 were at present formed in front of their premises, it is proposed not to inter- 

 fere with such at present, if the parties object to an embankment, but to 

 leave them, forming open docks or recesses. (Plate VI. Fig. 2.) It is sup- 

 posed that four of these docks may at present be required between Westmin- 

 ster and Blackfriars Bridges, viz., one at Northumberland Wharf, one above 

 Waterloo Bridge, terminating with the Bridge Stairs; one above the Temple 

 Gardens, and one commencing at Whitefriars Dock and terminating with the 

 stairs at Blackfriars Bridge. There may be modifications in the sisuation of 

 these, at the request of parties. As the deepening of the navigable channel 

 may tend to draw down the ground of those wharfs into the river, it is pro- 

 posed, where required, to support the same by close piling in the line of the 

 embankment, the top of this piling not to be above the level of the ground 

 where it is driven ; tlie loose mud to be taken out from these recesses or 

 docks, and small chalk and gravel, laid in a regular slope, to be substituted ; 

 this, and the wash by the winds and steamers, will, it is supposed, keep the 

 bottoms clear of mud without much trouble. 



The dotted lines upon the plan show the proposed future margin of the 

 river on both sides; but as it is proposed first to embank the north or Mid- 

 dlesex side, between Westminster and London Bridges, the number and po- 

 sition of the docks or recesses on the Surrey side have not been considered. 

 Tv'or is it intended entirely to preclude barges from lying oulsidc the em- 

 bankment ; but the stations there will be less convenient than the recesses 

 for such trades as coal and timber. 



Should a terrace, or even a railway, be thought desirable, the marks upon 

 the plan (coloured yellow) show the position of piers to support flat 

 arches, 100 feet span. The roadway, which is shown by dotted lines, might 

 enter on the embankment at WhitebiiU and terminate at Blackfriars Bridge, 

 crossing Hungerford and Waterloo Bridges at the level of their roadways, 

 and thus communicating with these thoroughfares. 



(Signed) James Walker. 



[We have not been able to give an engraving of Mr. Walker's plan, but it 

 will be sufficiently understood, wiih the following explanation, by a reference 

 to the annexed engraving. Mr. Walker's plan has a solid embankment from 

 Westminster Bridge to Scotland Yard, then a recess ; then embankment in 

 front of Hungerford Market to Salisbury Street, then a recess to Waterloo 

 Bridge; then embankment in front of Somerset House to a little below 



Arundel Street, then a recess for the wharfs at Essex Street; then embank, 

 ment fronting the Temple Gardens to Whitefriars Dock ; and, lastly, a recess 

 to Blackfriars Bridge. The dotted line on the Surrey side of the river is 

 Mr. Walker's boundary for an embankment. — Editor.] 



Appendix. — Description of Mr. Page s Plan (B.) 



Mr. Page's plan pre-supposes terraces and side channels, and may be re- 

 ferred to under three heads: — 



First, as any embankment constructed upon this principle may affect the 

 Thames as a navigable river. 



Secondly, as it may affect the wharfingers and other proprietors on its 

 banks. 



And, Thirdly, as it may improve the means of communication in the me- 

 tropolis by opening new facilities for its traffic, and for promoting generally 

 the health and convenience of the public. 



In the first case, the arrangement is based on the principle that any ab- 

 straction of the tidal water from a navigable river by embanking or otherwise, 

 must injure that river to a certain extent below the locality of the embank- 

 ment ; and although the injurious efi'ect of embankments may be greater in 

 estuaries which depend for their depth of water on the tide alone, it is a 

 known fact that the reservoir of water in a river at any particular spot now 

 availahle for the scour, operates to that efli'ect as far as it runs out with the 

 ebb tide. Taking as an instance the locality of Hungerford, the water in the 

 broad expanse of the river in that part operates iii scouring the hed of the 

 river as low down as Woolwich, according to the duration and velocity of 

 the ebb ; and it is assumed, therefore, that any abstraction of this water 

 must, to a certain extent, deprive that portion of the river of its present 

 scour. 



It is further assumed that it is desirable in all navigable rivers to attain 

 great depth and moderate velocity ; that the permanent and efficient scour is 

 produced by depth of water and moderate velocity combined, as is instanced 

 in the beds of all rivers as they approach the sea ; and that, therefore, the 

 greater capacity of a river at high water at any particular spot, the more im- 

 portant is that water for scour, because it then acts with the greatest effect, 

 namely, when the greatest body of water is passing down, say from high 

 water to half ebb. It is therefore also assumed, that the loss of water at 

 the sides and bays of a river cannot be compensated for by deepening its 

 raid-channel,' inasmuch as the water so gained, if any shoal or shelf occurred 

 below it, would not fiow away in the ebb, remaining in fact in the reservoir 

 dredged for it ; or, if being higher than the surface of the water below, it 

 did flow down, would be available only towards low water, when, though the 

 current is stronger, yet, for want of body of water, it would be ineflicient in 

 producing scour. 



It would appear to be admitted, from the observations of engineers of ex- 

 perience, that the river Thames has been injured by sohd embankments ; that 

 in the case under notice the effect of such embankments from Hungerford to 

 Milhank is shown by the accumulation of mud banks below them ; that not 

 only the tendency, but the practice in every alteration by the river side, has 

 been to encroach upon the river, even by projections beyond a straight or a 

 continuous line ; and in the few cases where engineering authorities have 

 been consulted, it would appear that the principle of non-abstraction of the 

 tidal water, tliough fully acknowledged, has been perverted to suit particular 

 cases. It is also assumed, therefore, that in any alteration of a public nature, 

 the condition of preventing further encroachment should, if practicable, be a 

 leading feature. 



Secondly, With regard to the wharfingers, the object of the proposed plan 

 is to leave their wharfs, warehouses, means of unloading, &e., in tlieir present 

 state; in fact, not to interfere with their property, and to allow all the 

 accommodation for their barges, &c., in the very places they now occupy, as 

 may be consistent with the width required for the main stream of the nver ; 

 and, 



Thirdly, With these provisions for the river, and for the wharfingers, the 

 plan provides for increased facilities of communication between several points 

 of the metropolis, and extensive promenades by the river side. 



For obtaining a more uniform boundary for the main stream of the river, 

 it is proposed to construct lines of terraces from Milbank, where the river is 

 600ft. in width, to Queenhithe, where itistioOft. ; the width between the 

 terraces varying from 650 to 750ft., and leaving side channels between the 

 terraces antl the wharfs varying from 303 to 150ft. in width. The width of 

 the terraces is 40ft. ; 10ft. of which on the river sideis appropriated for foot 

 passengers, and the remainder for carriages. 



The areas of these side channels are, on the Middlesex side, 37 acres, and 

 the Surrey side 4O2 acres ; together 77^^- acres, or more than double the area 

 of tlie London and St. Katharine's Docks, exclusive of the basin. 



The lengths and widths of the side channels are shown by the following 

 table : — 



1 This may he illustrated by supposing that in the part to be deepened there are five 

 feet water at the lowest run of the tide, and the hed of the river he then dredged lour tijet 

 deeper ; there would then be nine feet water at the lowest run uf the tide; but no portion 

 of tins water would run out and scour the river below. It is asauiii .d, tbeieioie, Ihat all 

 the water which does scour the river below anylocaitv, is contained betuceu low water 

 mark and higli water mark; and that tlie greater cubic quantity uf water bet-.veen ihOKd 

 wo points, the more eflicient will be the scour. 



