any wood which a peculiar demand rendered more profitable than others. As, however, this does not appear to be the case, I would make the following remarks, with a view to eliciting opinions from the author of the Paper or any member having special knowledge on the subject: a. Taking it for granted that the new method of "wiring" for hops will be such a success as to generally supersede the old pole system, can any better course be pursued than to include a large proportion of larch in making new plantings for underwood? I believe that whole timbers. will always be preferred to sawn posts, on account of their greater durability. b. Imagining that the returns from our present system of management may diminish still more, will it not become the most profitable proceeding to plant a quick-growing wood for cutting, say, every four or five years, for firewood only? On such barren soils as are afforded by the lower greensand, where birch springs up naturally, I feel certain this would prove to be the most remunerative course to pursue. c. Why do our walking-sticks come so largely from abroad? I believe that local factories (even if only established for the preliminary processes of cutting, peeling, and filing) would prove not only a financial success, but of considerable benefit to a rural population, and of great service in the conversion of our underwoods. Such woods as hazel, black and white thorn, holly, Scots fir, cherry, &c., might certainly be utilised in this way. In this connection, I imagine it is not generally known that a large demand exists for furze for export to New York, notwithstanding the duty put upon it there. G. S. MITCHELL, Fellow. On Mr. Grantham's Paper on "Recent Experience in Sewage Filtration considered in relation to River Pollution." ("Transactions," Vol. XXV., pp. 401-422.) I have received the following remarks from Mr. SANTO CRIMP, M. Inst. C.E., who was unable to be present at the discussion on my Paper. They are important as coming from one whose practical experience and intimate knowledge of the treatment of sewage have been exemplified in his successful management of the Wimbledon Sewage Farm: I regret that I was prevented from attending the meeting on the occasion when Mr. GRANTHAM'S Paper was read. It was an excellent résumé of the subject of sewage disposal. The key note of successful sewage farm management was struck in the reference to the Abingdon Sewage Farm. I have seen the effects of unskilful management at Wimbledon, where the farm, which is mainly of clay, was for a time ruined-from the sewage purification point of view-by reason of the underdrains, and by careless management. A great nuisance was the result, which, however, I partly remedied by taking up vast numbers of drains, and by carefully attending to the surface of the land, the local board at the same time appointing a thoroughly capable manager, Mr. SNOOK, who has since turned out one of the best effluents to be found in the kingdom. In another case I was recently consulted with regard to the sewage disposal of Industrial School buildings, with a population of about 1,000, surrounded by land of excellent quality for sewage treatment, but where a nuisance existed simply due to careless management. In that case I recommended the proper preparation of a small area for sewage treatment, and insisted upon the importance of efficient management; and, indeed, in several other instances in which I have been consulted, I have found bad management of both sewage farms and chemical processes, to be the main cause of failure. The author of the Paper referred to Chiswick, Acton, Mortlake, and other towns on the Thames below the intakes of the water companies, where the treatment was satisfactory, whether the effluent was passed through filters or not, but it is not to be assumed that these processes would be equally satisfactory in cases where the effluent was poured into a small stream. It would be difficult to produce a nuisance in the Thames with an effluent only equal to part its volume, although the very same effluent would produce a nuisance in a small stream, as, indeed, has been proved at Leicester, Birmingham, Tottenham, and elsewhere, where treatment on the land has been found to be the only effective remedy. Tottenham may, perhaps, be an exception. It now discharges its sewage into the metropolitan system, having failed to produce an effluent sufficiently pure for the canalised portion of the Lee, into which it formerly passed. With regard to the question of self-purification of rivers, I think that this is, probably, best settled from the dissolved oxygen point of view; because organic matters are mainly broken up by minute organisms, of which there are two main families—one requiring oxygen for their subsistence, and breaking up organic matter into harmless mineral compounds and gases; the other, when the oxygen is used up, taking the place of the former, and carrying on the work of disintegration, but with the production of most offensively-smelling gases, which produce in certain cases an intolerable nuisance. Obviously, therefore, every effort should be made to prevent the undue abstraction of the dissolved oxygen in streams, by the pouring into them of impure liquids. Massachusetts was referred to by the author, and I cannot too strongly express my admiration of the careful manner in which the experiments at that city have been carried out, and the really extraordinary results obtained by filtration through sand, when the best way of applying the sewage had once been ascertained. With regard to the Berlin sewage farm, the authorities of the city are evidently possessed of the usual astuteness of the Teuton, and have once for all solved the sewage problem, so far as Berlin is concerned, and this without wasting money on chemical processes and patent nostrums. It would, of course, be rash to say that London sewage could with equal ease be disposed of on land, for many of the details differ; the sewage flow per head, for instance, is at Berlin only one-half that of London; and there are other circumstances to be considered before pronouncing a definite opinion. But at the same time, with land in Essex selling at £8 10s. per acre, it is not beyond the bounds of possibility that London sewage could be applied to land without imposing a heavy burden upon the ratepayers. The cost of the present system is, for working expenses and chemicals and also sludge disposal, £110,000 per annum. This sum capitalised would be upwards of 34 million sterling, with which much might be done in the direction of applying the sewage to the land, and producing practically the only crops that can now be profitably grown on a large scale in this country, namely, grass, rye-grass, and roots. A vast number of cows could then be kept, and London could itself produce much of the milk, butter, and cheese now obtained from the Continent. It will be observed that Mr. CRIMP concurs in the opinion generally expressed at the meeting, that success in treating sewage depends on careful and skilful management. He also distinguishes between the effect of the state of purification of an effluent when discharged into a small stream, and that when it is poured into a large one. As assistant engineer to the London County Council, his remarks on the possibility of applying the sewage of London to land will be gratifying to those who maintain that disposal on land is the best solution of the question. RICHARD F. GRANTHAM, Associate. SECTION III. PROFESSIONAL QUERIES. Information is sought on the following points: OXLVII. DILAPIDATED FENCE-INJURY TO SHEEP-LIABILITY. A is the owner of a dilapidated fence separating his land from that belonging to B. B's sheep suffer damage from crossing and recrossing this fence. Can B obtain any redress as against A? SUPPORT OXLVIII. RETAINING WALL-PUBLIC FOOTPATH. (For Replies to this Query, see pp. 139-141.) A road belonging to, and repairable by, the County Council runs past a garden, which at that point is some five or six feet below the level of the road. The road is kept in its place by a retaining wall, upon the top of which the fence wall of the garden is erected. Owing to heavy rains a portion of the retaining wall is undermined and collapses, bringing down with it a portion of the garden wall, and also part of the footway of the road. Whose duty is it to repair the damage as between the County Council and the owner of the garden, both as to the retaining wall and the garden wall erected upon it? CXLIX. UNEXHAUSTED IMPROVEMENTS. (For Replies to this Query, see pp. 141-143.) What are the respective rights and liabilities of— b. The representatives of the offgoing tenant; in the following case? |