inaction are found upon most boards, but they too often are in a minority.

As regards sewage pollution, no difficulty can be reasonably alleged now about the process or method which should be adopted with reference to any particular place. Data are now available to guide all who are capable of being influenced by facts; and if those who have to exercise judicial functions in dealing with questions of sewage disposal will disregard prejudice, and decide on the evidence of facts as distinguished from crotchety opinions, not a fractional part of the trouble and expense would arise out of sewage inquiries. At all events, I am sure that no justification exists now for strife and contention about this source of pollution compared to that which was fairly permissible ten years or so ago.

Much of the difficulty which attends the prevention of sewage pollution to a river arises from the outfall sewer being made use of to convey also the whole of the rainfall from the populated area draining into the sewerage system. This ought not to be the case, as the separation of the rainfall, or, at all events, of a considerable part of it, enables the sewers to be more efficient and self-cleansing, and causes the sewage which is removed by them to be brought to the point of discharge in a fresher state than is possible where the sewers are calculated to convey the larger volume. They then inevitably become sewers of deposit in dry weather, and give off dangerous gases. In wet weather the decomposing sewage is flushed away to the outfall in a state which is unsuitable for utilisation on land and is destructive to fish, by exhausting the oxygen from the river.

The law should be precise that no polluting matter whatever should be passed into a river. If a small amount does no harm, or even admit that it does good, to fishes, it is better to prevent them altogether from having this alterative diet than to run the risk of their having far too much, with the certainty of nuisance and of interference with the enjoyment of the river. The following letter, which appeared in the Times last autumn, is interesting, and serves to show the danger of leaving in doubt the permissibility of discharging sewage into a river : 'Sir,-It is a remarkable fact that at the meeting of the Severn conservators recently at Worcester the report stated that the salmon disease had entirely disappeared during the late summer. The past season has been the longest, warmest, and driest known in this country for many years, and as the Severn was correspondingly low, and therefore must have been more than usually polluted (in proportion to the small quantity of water), yet the fish disease disappeared! I am also informed by fishermen that some sorts of fish are so well known to congregate near the mouths of sewers that anglers and others make it a rule to seek and find them there. This seems to imply that diluted sewage is attractive to these fish, either as an alterative in their diet or medicinally, and otherwise grateful to the piscine stomach. These facts no doubt confuse, if they do not reverse, our ideas as to the destruction of fish by the pollution of rivers. Where chemicals or other pungent refuse from manufactories are introduced into our streams there can be no question as to their baneful effects on fish-lif, but that the sewage of towns is not objectionable to these creatures is a fact which ought to be taken into account in any future Pollution of Rivers Act.

The argument hitherto urged, and unanimously accepted, that the discharging of sewage into our streams tended to the destruction of the fisheries would seem to be no longer tenable.

'Yours, &c.

'J. NOAKE, 'Worcester.' 'Severn Conservator.' Although I hold that ultimately no pollution of a river should be allowed, yet where a stream has been employed to carry off polluting matter from manufactories, the remedy that has to be provided requires to be enforced carefully and, perhaps, slowly at first, with a view to prevent sudden injury to trading interests which might lead to a discontinuance of the trade, and a consequent loss both to the manufacturer and to the poorer classes in the district. A considerable part of the polluting matter now passing into streams is capable of being removed by subsidence or mechanical straining without chemicals. As tanks are required in any system of sewage treatment, they could be made a sine qua non even at the outset, and their provision could be made absolutely compulsory under the Act to commence with. The size of the tanks was considered by the Rivers Pollution Prevention Commissioners, and they proposed that the flow for six hours should be impounded. This, however, admits of variation by constructing the tank in duplicate with an upward straining-frame, by which the suspended matter would be arrested and flushed or pumped out at intervals, the fluid passing continuously.

The distinction that is made between a channel constructed before the passing of the Act of 1876 and one made since seems undesirable. If discretionary power is vested in those who have to enforce the Act, I think this distinction could be safely done away with.

The Rivers Pollution Commissioners in their fifth Report recommend the condemnation of liquids which did not comply with the following standards :(a) Any liquid which has not been subjected to perfect rest in subsidence ponds of sufficient size for a period of at least six hours, or which, having been so subjected to subsidence, contains in suspension more than one part by weight of dry organic matter in 100,000 parts by weight of the liquid, or which, not having been so subjected to subsidence, contains in suspension more than three parts by weight of dry mineral matter, or one part by weight of dry organic matter in 100,000 parts by weight of the liquid.

(b) Any liquid containing, in solution, more than two parts by weight of organic carbon, or 3 part by weight of organic nitrogen in 100,000 parts by weight.

(c) Any liquid which shall exhibit by daylight a distinct colour when a stratum of it, one inch deep, is placed in a white porcelain or earthenware vessel.

(d) Any liquid which contains, in solution, in 100,000 parts by weight, more than two parts by weight of any metal except calcium, magnesium, potassium, and sodium.

(e) Any liquid which, in 100,000 parts by weight, contains, whether in solution or suspension, in chemical combination or otherwise, more than 05 part by weight of metallic arsenic.

(f) Any liquid which, after acidification with sulphuric acid, contains, in 100,000 parts by weight, more than one part by weight of free chlorine.

(g) Any liquid which contains, in 100,000 parts by weight, more than one part by weight of sulphur,

tion this Session. The Sanitary Institute of Great Britain' has appointed a committee to consider this matter. The council of the Parkes' Museum' are also fully alive to the need of action, hence my addressing you to-day.

If the amendment of the Act of 1876 is taken per se and independently of the other matters affecting local government, I think that modifications can be without difficulty made by which the optional character of the Act will be changed, and its enforcement made obligatory upon the local authorities. The other necessary amendments which have been indicated in the foregoing remarks can, in my judgment, be easily drafted, and in terms which do not admit of doubt. If the prospect of carrying the larger measure of local government is remote, I incline to the opinion that an effort should be made to shape the Bill which is now before Parliament so that it might pass this session, and so accomplish a reform of a great and increasing evil, upon which public opinion has been unmistakably expressed. I conclude by asking the co-operation of all in the effort which is now being made to prevent a continuance of the present pollution of the rivers of the country, which has been truly characterised by Lord Shaftesbury as a 'national evil.' Their restoration to their original purity will, I trust, be the result of the long-sustained efforts on the part of those who have worked earnestly in this cause.

MR. E. LEWIS THOMAS, B.A., of Sidney Sussex College, Cambridge, and Lincoln's Inn, has been appointed executive officer of the Mansion House Council on the Dwellings of the People.

A HEALTH RESORT.-The parish of Presteign, in Hereford and Radnor, is very remarkable for the health of its inhabitants. By the last census it contained 2,214 persons; of these twelve now are in their seventieth year, seven in seventy-first, three in seventy-second, two in seventy-third, one in seventy-fourth, six in seventy-fifth, five in seventy-sixth, eight in seventy-seventh, two in seventy-eighth, one in seventy-ninth, seven in eightieth, two in eighty-first, seven in eighty-second, four in eighty fourth, three in eighty-fifth, one in eighty-sixth, one in ninety-second, and one in ninety-eighth year. This last is able to gather potatoes in fer garden. One couple have been married fifty years, another fifty-three, another nearly sixty-five. An aged person in indifferent health came nearly five years ago to the parish, and never since has had a day's illness.

SANITATION IN NAAS.-We learn from the Irish

Builder that on the recommendation of Dr. Smyth, medical officer of health for Naas, the guardians of the Union have adopted the 'pail' system as the most effectual for improving the present defective sanitary condition of the town. The medical officer stated that out of 500 houses supposed to be in Naas, 400 were without sanitary arrangements of any kind, and that their owners would gladly adopt the 'pail' system, for the sake of economy. The proposed scheme would, in the opinion of Dr. Smyth, 'mean an improved sanitary administration, and, in proportion to its efficiency, would, in a general way, raise the standard of health, and in a special way increase the security against contagion. It would, silently and surely, teach the people the lesson of cleanliness in their dwellings, in their persons, and in their habits. It would bring before the minds of many owners, probably for the first time, the necessity as well as the advisability of improving both without and within, many of the present wretched homes of the poor. It would also justify many an owner in exercising his authority to enforce cleanliness, for an uncleanly tenant is a nuisance and a danger to the community.'

THE DOGMATISM OF SANITARY

REFORMERS.

By D. J. EBBETTS.

IT seems to be the fate of all young sciences, in their earlier stages, to afford free scope to the dogmatism of their less cautious expounders.

The professor of a new science must possess considerable self-control and some modesty, if he does not fall a ready victim to the Nemesis of dogmatism in face of the occasional insecurity of his position. Otherwise the more insecure his position the more easy his fall.

We can easily see that the imperious utterances of an incautious exponent will prove their own Nemesis; for I suppose most of us are agreed that the only way to induce people to take an interest in sanitary science is by pointing out its momentous importance to all in simple language; and by persuading them that all we recommend is necessary to attain the desired end. Now there may be a few weak people here and there who will be content to accept a dictatorial assertion that such and such a thing is absolutely necessary, without further inquiry, but such persons are but poor supporters of any cause, for the first breath of adverse criticism will draw them away as readily as they were originally beguiled. On the other hand most people, I hope and believe, will require to be shown why such things are so necessary, and if their inquiries are only met by general assertions, will pay but little heed to their quasi instructors.

To render myself clear I will take a case in point, though in doing so I may probably shock a great many people.

You will find it often asserted in the most positive manner that a water-closet must not be supplied from the same cistern as the drinking water. Now if you look to see why this prohibition is imposed upon us you will find only a general statement that pollution of the drinking water is sure to follow upon such an arrangement. And anyone interested in the subject will remark that the exception is not taken for instance, as a spindle valve with air-pipe in the to any particular arrangement of water supply, such, cistern itself, but applies with charming impartiality to all arrangements alike.

In the annotated edition of the Model By-Laws, p. 105, after insisting upon the necessity of forbidding water-closets to be supplied direct from a rising water main-a necessity which for several reasons it is easy to admit—and after insisting on the closets being supplied from a cistern, the text continues, 'but even when such a cistern is provided, there still remains a tendency for the escape of foul air from the basin of the closet up the service pipe and through the body of water in the cistern itself, thus leading to contamination of the water.'

I suppose this authoritative statement ought to be sufficient for most men, but it will be noticed that it is not attempted to be shown how the foul gases could pass up into the cistern-it is simply stated that a tendency of that kind remains.

Now, leaving this subject for a moment, I suppose my experience has only been that of many others when say that I have found great difficulty in persuading people in the occupation of old houses in town, replete with every ingenious appliance for the conveyance of sewer-gas to the interior of their dwellings, to have even the most glaring and mis

chievous errors in house drainage and plumbing rectified. The great cost of such work, when properly done, in proportion to the value of the house, in addition to the inconvenience necessarily incident to the presence of workmen in the building, prevents so many from undertaking work of this kind. Anything which tends, therefore, to increase unnecessarily the cost and disturbance of such work, serves materially towards preventing the necessary and pressing sanitary wants from being attended to.

The provision of an additional cistern and supplypipes for closets only, in an existing building, is often a serious item. Very often it is difficult to find a suitable place for the cistern; it generally involves considerable disturbance of existing work of different kinds, and always results in a serious additional outlay. The small supply cistern fixed in the w.c. itself, so often used in connection with wash-out closets, is not free from these objections, and is subject to another which it is not necessary for me to enter into at present.

Feeling convinced, then, of the undesirability of insisting upon more disturbance of existing plumbers' work than was really imperative, I had the temerity some three or four years ago to ask a sanitary engineer whether it were not permissible to connect a valve w.c. direct from a drinking-water cistern. Never shall I forget the look of professional pity Iwith which he informed me that no one who had any knowledge of sanitary engineering would think for a moment of doing so, that it would result in tainting the water, typhoid fever, &c. Recovering what courage I could, I pressed him to tell me in what way the water would become tainted, but I could only extract the usual general statements that the pipe might be emptied, and so the water in the cistern would be in open connection with the closet.

I have, in fact, been unable to extract from any authority a clear statement of the manner in which the danger accrues.

Now, if we look into this question for ourselves, we shall find it not quite such a simple one as many would have us suppose. How can the water in the cistern be tainted? Let us assume that we have a good valve water-closet apparatus, with a 1 inch water-valve connected with the cistern. We will suppose that the closet has a P trap, with outgoing into a closed soil-pipe connected directly with a foul old drain. I am assuming this for the sake of argument, for of course no one with any knowledge of the subject would allow the soil-pipe or drain to remain in this state, whatever he proposed to do to the closet.

We will assume that the house has remained empty for some time, and the handle of the closet, by some curious coincidence, has been fixed up. As a consequence, the water from the cistern will soon empty itself down the soil-pipe; for we may as well assume, to complete our pleasant picture, that the water has been cut off at the rising main by an overbearing or long-suffering water company. The foul gas, we must admit, will pour up freely from the soil-pipe, and, it is assumed, will find its way up the supply-pipe to the cistern. But why? What is to produce a strong draught up this 1-inch pipe to suck in the foul air at one end through the narrow flushing rim and emit it at the other end into the

cistern ?

But supposing we admit-and, having admitted so much, we had better hesitate no longer-that the

pipe once empty, the foul gas would soon ascend it. Why, then, I would point out that the pipe is not empty yet. Anyone who looks at an apparatus with the usual water-valve will see that the centre of the water-valve is some nine inches below the centre of the inlet to the basin, so that the supply-pipe descends to the valve and ascends to the basin. It follows, therefore, that after emptying the cistern there still remains two or three feet of the 11-inch pipe filled with water. This water will evaporate in time, no doubt; but how long do you think it will take to evaporate? There are only two small surfaces of water, neither of them exposed to draught or rapid movement of the air. I believe I am within the mark in saying that this water would not evaporate in our climate under six months.

A pertinacious opponent may contend that after the lapse of this time gas would ascend the pipe to the cistern, and, water being admitted to it by the relenting company upon the opportune arrival of a new tenant, the contents would be dangerously contaminated.

But bear in mind that the dreaded sewer-air has for six months or more been admitted in volume into the house night and day, it has filled every nook and corner of that ill-fated and far from desirable residence, and wherever the tank may be located sewer-gas has found its way to it from the house long before it has been able to reach it by the pipe, so that, had there been a separate cistern for household purposes, it would have been treated as badly as the other one.

Seriously, if a tenant were to take a house in such an unsavoury condition he would be forced to have it first of all thoroughly disinfected, and certainly would be obliged to have all the cisterns emptied and cleansed, so I fail to see what he would gain by a separate cistern.

In arranging a new house I should prefer as a matter of sentiment to supply even a proper valve w.c. from a separate cistern; but in old houses, where it is desirable not to increase the expense of sanitary work more than is absolutely necessary, I should not in my present state of ignorance think of doing so, and I venture to think that I have shown that it cannot be really necessary to do so.

There are several other dogmatic laws generally accredited to sanitary engineers that might be controverted with some success, but for the present I hope that I have justified my warning to all to be chary of encouraging dogmatism in this as well as in all other scientific work.

MESSRS. BANNER BROS., II Billiter Square, E.C., have been commissioned to entirely overhaul the sanitary arrangements of Herbert House, Belgravia, the town residence of Lady Herbert of Lea, and substitute the 'Banner system'throughout. The work is being carried out under the able superintendence of Mr. E. A. Hubert, Messrs. Banner's engineer. We learn also that Banner's fixed ventilators are being used on the new portable hospitals that are being sent out to the Soudan.

SANITARY inspectors are decidedly becoming awakened to the responsibilities of their calling. We note with pleasure and approbation that Mr. Joseph Lindley, Assistant Sanitary Inspector in the Sanitary Department, Leeds Corporation, has gained in the Science ExaminaHygienic Elementary Animal Physiology and Advanced tions, held in Leeds in May last, certificates for Advanced Building Construction. The practical advantage of an intelligent knowledge of the first and last of these subjects for a sanitary inspector, is incontestable.

DAMP WALLS IN DWELLINGS.

By G. H. BLAGROVE, A.R.I.B.A.

AMONG the many fruitful sources of ill health consequent upon defective modes of building, damp walls are certainly not the least formidable or most easily remedied. Unlike the offensive smells arising from imperfect drainage, damp in walls does not make itself immediately evident to the senses, and it is often disregarded, while its baneful effects are ascribed in part to other causes. The difficulty and expense of remedying such an evil are sometimes considerable, and recourse is too often had to temporary expedients. Thus, when a room has been unoccupied for some time, and the presence of damp is evident in its walls, it is thought sufficient to light a fire. By this means the signs of damp may be made to disappear from the walls, while it is still present in the atmosphere, although in a rarefied form. During the cold hours of the night, however, it is obvious that condensation must ensue, and it is probable that the walls, having once been damp, will again become so. More moisture will be absorbed from the external atmosphere, to be again drawn in and rarefied by heat, and again allowed to condense itself upon the objects in the room or the persons of its occupants. Such is the process that must take place in moist situations, in a greater or less degree, according as the walls of a dwelling are more or less pervious to damp.

There are a variety of ways in which a wall may become impregnated with moisture, and it is important that these should be thoroughly understood before remedies are sought for or applied. Internal walls may absorb moisture from the ground beneath. This is liable to take place in proportion to the depth of the foundations, by which the tendency of the moisture to force its way upward is accelerated by any increase in the weight which presses upon it from above. Having once made its way into a wall, it rapidly rises, partly by evaporation aided by capillary attraction, and the wall becomes permanently damp. An external wall may become damp from this cause only, or from the far more serious one of being in contact with the earth. It is quite clear that, whatever the nature of the soil, the pressure of its own weight must cause a large amount of moisture to exude laterally, except in very dry weather, and that such moisture is readily transmitted through any ordinary thickness of walling, and must be a perpetually recurring source of danger to health. No room adjoining such a wall should be permitted to be used for human habitation.

An external wall may become damp through the action of driving rains, or from mere contact with a moist atmosphere. The effects are similar to those produced in a wall exposed to contact with the earth, except that they are less strongly marked. The ingress of moisture aided by wind force naturally takes place most frequently upon those sides of a building which face in southerly directions. Setting aside such local accidents as the bursting of rain-water pipes, or the leaking or overflowing of eaves gutters, there is only one other cause of permanent dampness in walls to be noticed, and this is the downward soakage of water from the top of a wall, or from an off-set. In old walls, where the mortar or cement has suffered partial disintegration, a certain modicum of rainfall is absorbed by the brickwork or masonry, and, by gradually percolating

through the open joints, is transmitted from brick to brick, or from stone to stone, until the walls become damp, sometimes to the depth of the entire upper storey of a house. At off-sets, or where stone cills or balconies are built into a wall, there is always a danger that repeated falls of rain upon the upper surfaces of such projecting parts may drive a certain amount of water through the joints of the walling, from whence it will soak downwards, and sometimes upwards as well.

In adopting remedies against damp walls, prevention is better than cure. The customary precautions followed in all sound building work are, of course, well known to architects and contractors, but the general public ought to be informed of their relative value and importance. To prevent moisture from soaking up into a wall from the ground below, it is usual to build in a damp-proof course throughout the entire thickness of every wall. This dampproof course is a layer of some impervious material, and must be placed in the wall above the highest level of the earth with which it is in contact, and below any wall-plates or other timbers connected with the construction of the floor. A double course of slates set and bedded in cement, the upper course breaking joint with the lower, has often been used as a damp-proof course. It is economical, but as the slates are liable to fracture from any settlement in a building, it is not to be recommended. A single course of glazed pottery slabs is often used, the joints between the slabs being left empty, to prevent the damp from rising through them. This, though it forms an effectual damp-proof course, destroys the bond of the wall, and is therefore objectionable upon structural grounds. Sheet lead is efficacious, but will be found too expensive for general use. In some parts of the country, thin slabs of impervious stone have been used with satisfactory results, and there is no doubt that a double course of plain tiles in cement will answer well, and be less liable to fracture than slates. Various kinds of asphalte are manufactured for this purpose, and a thick layer of this material will form an effectual barrier to damp, and will not be subject to injury through settlements. Cases have been known when asphalte damp-proof courses have been eaten away by rats, and where such vermin exist it is therefore unadvisable to employ it.

When damp rises in a wall which has been built without a damp-proof course, the proper remedy consists in underpinning it, and inserting one. This involves considerable expense, but all other expedients are inferior to it. If the wall be only slightly damp, the room adjoining it may be kept tolerably dry by rendering the wall with Portland cement, or better still, with glazed tiles set in cement; but if there be much moisture present, it will be liable to evaporate under the floor, when the latter is boarded, and so to impregnate the atmosphere of the room.

To separate the underground portion of an external wall from contact with the earth, it is usual to build a dry area around it, extending to a depth below the damp-proof course, and being about 12 inches wide at that part. Sometimes the outer wall of the area is made of a sufficient thickness, and built at a sufficient slope, to act as an independent retaining wall against the earth, in which case the area is open at the top, and admits of a free circulation of air. The top of the outer wall should be above the level of the surrounding earth, to prevent any surface water from flowing into the