The object of this door was to prevent the ingress of much more foul matter from without; and its misfortune was, that in so doing it necessarily pent up a concentrated putrid gas within. At length Nephelo escaped; but alas! it was from a Newgate to a Bastille—from the drain into the sewer. This was a long vaulted prison running near the surface underneath the street. Shaken by the passage overhead of carriages, not a few bricks had fallen in; and Nephelo hurrying forward, wholly possessed by the one thought—could he escape?—fell presently into a trap. An oyster-shell had fixed itself upright between two bricks unevenly jointed together; much solid filth had grown around it; and in this Nephelo was caught. Here he remained for a whole month, during which time he saw many floods of water pass him, leaving himself with a vast quantity of obstinate encrusted filth unmoved. At the month’s end there came some men to scrape, and sweep, and cleanse; then with a sudden flow of water, Nephelo was forced along, and presently, with a large number of emancipated foulnesses, received his discharge from prison, and was let loose upon the River Thames. Nephelo struck against a very dirty Drop. “Keep off, will you?” the Drop exclaimed. “You are not fit to touch a person, sewer-bird.” “Why, where are you from, my sweet gentleman?” “Oh! I? I’ve had a turn through some Model Drains. Tubular drains, they call ’em. Look at me; isn’t that clear?” “There’s nothing clear about you,” replied Nephelo. “What do you mean by Model Drains?” “I mean I’ve come from Upper George Street through a twelve-inch pipe four or five times faster than one travels over an old sewer-bed; travelled express, no stoppage.” “Indeed!” “Yes. Impermeable, earthenware, tubular pipes, accurately dove-tailed. I come from an experimental district. When it’s all settled, there’s to be water on at high pressure everywhere, and an earthenware drain pipe under every tap, a tube of no more than the necessary size. Then these little pipes are to run down the earth; and there’s not to be a great brick drain running underneath each house into the street; the pipes run into a larger tube of earthenware that is to be laid at the backs of all the houses; these tubes run into larger ones, but none of them very monstrous; and so that there is a constant flow, like circulation of the blood; and all the pipes are to run at last into one large conduit, which is to run out of town with all the sewage matter and discharge so far down the Thames, that no return tide ever can bring it back to London. Some is to go branching off into the fields to be manure.” “Humph!” said Nephelo. “You profess to be very clever. How do you know all this?”