Mr. RAWIJNSON admitted, that his paper might be considered loose and discursive, but he had written it chiefly for the purpose of eliciting opinions on a question of great social importance, and he was ready, in answering the questions put to him, to afford any additional information in his power. I t might be said, that there were some positions unduly assumed ; if so, they would be overthrown, and the erroneous conclusions would be pointed out.Perhaps the best method of opening the discussion was to state a few facts, in connexion with the drainage of a town, where, from local circumstances, only earthenware pipes had been used. He alluded to the town of Hitchen, where upwards of 60,000 feet of pipe sewers, from 20 inches down to 4 inches diameter, and 2 feet 6 inches long each, had been in action for four months, with perfect success ; the average depth below the surface was 8 feet, and the outlet of the main sewer, which was 5000 feet in length, and only 20 inches in diameter, was laid, in part, beneath the bed of the river, at an inclination of one in eight hundred.This was designed for the sewerage of one thousand houses, of which only two hundred were at present connected, and for eleven hundred acrea of urban and suburban drainage. H e admitted, that some of the pipes, laid to a pumping engine, had been broken, from being laid in bad ground, but after being relaid in wooden troughs, no further fractures ensued. He was aware, that the system of' pipe sewerage had been, and must be, modified in practice, to adapt it to certain localities ; that in a rocky uneven bed, improperly loaded pipes would break, and if of large dimensions, they were very liable to be split longitudinally, or be fractured transversely, as it was very di5cult to get them accurately made and burned, and the false bearing at the sockets caused breakage. If in the case of Hitchen, the rule laid down in Mr. Roe's tables had been followed, the outlet must hau-e been 5 feet diameter, instead of 20 inches diameter.No attempt had been made to divert the natural flow of the surface-water ; the street gullies being connected directly with the pipe sewers. In this, as in the arrangements for all towns, an engineer must modify his practice to meet local circum, Qtances. H e was satisfied with the general results a t Hitchen, and as the

SOUTH COAST OB ENGLAND. 205Mr. REDMAN, in answer to questions by Mr. Walker, explained, that the authorities he had consulted, for the present state of the outline of the coast, were the Admiralty charts, and the Ordnance and other modern maps of acknowledged accuracy, and as far as was practicable, he had verified the topographical correctness of those documents, by personal inspection, having walked over, and carefully examined the whole length of coast described, for the purpose of preparing the paper submitted to the Institution. He had already given in the paper, the ancient authorities, and he had spared no expense, or trouble in obtaining access to the earliest maps and the works of the best topographical writers, as the subject was of vast importance in marine engineering, especially in reference to the construction of harbours and coast-works of defence ; and he submitted, it was most desirable, that such natural agencies, as had been described, and the instances of the compensating effects of alternating loss and gain, should be correctly understood.Mr. NEWTON directed attention to the recently-exposed remains of the Roman castrum, at Lymne: it might be presumed, that at one period, that building had been situated on the shore ; and that the high lands at the back, being filled with springs, not drained away by any agricultural operations, had caused an ext.ensive landslip, whereby the castle walls were carried bodily forward for some distance, altering the line of the coast and occasioning a deposit from the river, which probably debouched near it.' I t was worth investigation, whether the first accumulation at Dungeness, might not have been originally formed by a somewhat similar occurrence.Sir WILLIAM CUBITT, said, that at Rye he had counted twenty distinct ' fulls ' of shingle ; he apprehended that these ' fulls' coincided with, or at least were influenced, to some extent, by the lunar cycles. H e would throw out the suggestion for the consideration of those who had more leisure for observations of that kind than he had, as the question was one of great interest, both theoretically and practically. H e was of opinion, that Winchelsea Castle was originally built close to the sea, as the ' fulls' now extended from the Castle to the present high-water mark.Sir CHARLES LYELL had derived much practical information from the interesting paper just read : particularly from the portions treating of Hurst Point and the Chesil Bank, to which he had devoted some attention. T h e effect of recent storms, on these parts