The _Thames Tunnel_ was pronounced, by Canning, “the greatest bore in England:” he was bored to death by applications for Government aid in completing it, and hence spoke feelingly. It is now apparently done, though not finished, and is a cockney wonder, well worth a visit. Were it only in actual use as a thoroughfare under the bed of the Thames, thus realizing the original conception, it would not be without an element of true sublimity; but to see it degraded to a miserable show, scarcely paying for its keeper, and serving only to enable the visitor to say that he has walked under the Thames, is enough to justify one in naming it a folly. Its uses, however, may even yet be demonstrated to be great, and I cannot but feel that this noble work has not been executed for naught. It will even yet have a history. Pity it is that the Duke of Wellington had no occasion to use it, in planning the defences of the city on the memorable tenth of April, 1848. It needed but the passage of a single regiment, under his command, through this mysterious excavation, for actual purposes of surprise and stratagem, to give the place a charm forever; and had such a passage been by chance accomplished in the night, and led by the Duke in person, for the sake of some masterly result, a new and romantic interest would have been added as well to his own marvellous story, as to that of the Tunnel itself. If the caverny wine vaults of the London Docks were but connected with the Tunnel on one side, and the Tower on the other, so that there might be a sub-marine passage to the Tower, from the Surrey side, it would at least furnish associations of a military character to this daring achievement of Brunel.