374 On the intended Thames Archway 



has since occasioned it to have, particularly when I have 

 been in the company of ingenious and practical men in such 

 matters, and have introduced the subject, in order to hear 

 the ideas of others relating to it. Instead of piling ojf the 

 river, as I there hastily mentioned, I would suggest to the 

 consideration of those engineers who may turn their atten- 

 tion to the subject, an immense tub in form of the frustum 

 of a cone, secured by hoops outside, and polygonal framing 

 inside, but without either bottom or top, which being prin- 

 cipally of wood, might be floated at high water to the spot 

 where the tunnel is to be begun ; the bottom edge of it 

 might be so secured to the bottom of the river, by means 

 which will suggest themselves to competent engineers, as to 

 prevent the influx of water from the river, or the pressing in 

 of quick-sand or silt, after the water is extracted from the 

 tub bv engines ; and after a length, of 70 or 80 feet per- 

 haps, of the tunnel was constructed, its end might be so se- 

 cured as to admit of moving the tub, to include a new length ; 

 with scarcely any interruption to the navigation of the river. 

 I have often been sanguine enough, to expect to see se- 

 veral tunnels constructed under the Thames and other of 

 our important navigable rivers, in some instances, super- 

 seding, perhaps, the ancient bridges like that of London ; 

 but must confess, that the origin and proceedings of the two 

 Thames Archway Companies, which we have seen, and 

 particularly the proposals by the directors of one of them, 

 which follow, have occasioned me to doubt much, whether 

 I shall live long enough, to pass through a tunnel con- 

 structed, under their auspices, unless indeed a material change 

 takes place in their principle of proceeding. 



I am, sir; your obedient servant, 



John Farey. 



Westminster, May 12, 1809. 



Particulars of the strata met with, in sinking a shaft near 

 the Horse-Ferry in Rotherhilhe, and in driving a heading 

 thence under the bed of the Thames river, 1035f feet in 

 length, intended as a drain for the proposed road arch- 

 way : with an account of the progress and present state of 



the 



