382 On the intended Thames Archway ', 



this address to the public, before any plan be adopted, 

 however considerable its merits, or however eminent its 

 authors. 



In the design of any plan for this concern, engineers will 

 doubtles pay particular attention to the difficulties which are 

 likely to occur, from the situation of the quicksands, the 

 communication with them and the river, and the falls in the 

 bed of the river. And that they will not consider themselves 

 as prevented from offering plans for executing the tunnel 

 through the river itself, by means of caissons, coffer-dams, 

 or any other method (if such method appear to them pre- 

 ferable to the underground mode), provided in the execution 

 of such plans no impediment be occasioned to the navigation 

 of the river. 



It is necessary to state, that any alteration in the line of 

 the tunnel can be but inconsiderable, as it must be confined 

 within the limits of the ground laid down in the accom- 

 panying plan. * 



It is an important consideration with the Company, that 

 the size of the tunnel be large enough to admit two car- 

 riages to pass each other 5 or two of smaller dimensions, 

 each to admit a carriage. 



The Company contemplate a foot tunnel, only in the 

 event that a larger one should appear to be impracticable. 



The plans must be formed with regard to the tunnel being 

 lighted. 



N.B. That plan whose line is the shortest, and ascent 

 the easiest, will have great claims to preference, if equal in 

 merit in other respects. 



Reference to the Plate, 



Fig. 1, (PlateXL) section of the river and works. Fig. 2, 

 plan of the same. 



B the shaft. A B the drift- way, as far as it has been ex- 

 ecuted. The dotted lines De and EF, Fig. 1, show the 

 proposed ascent and opening of the tunnel. The dotted 

 lines in the plan, Fig. 2, show the proposed direction of 

 the tunnel. The width of the river at low water is 619 feet, 

 at high water 850 feet. The distance between the drift- 

 way 



