46-SANITARY SCIENCE.

BY JAMES S. DUNN, A.R.S.I., A.R.I.P.H.

A general discourse on Sanitary Science, even at a Congress like this, would, I fear, be of little avail, for under the title are included the questions of providing communities and individuals with Pure Air, Pure Water, Pure Food; the consideration of Climate and Soils; the healthy construction of Habitations, Schools, Workplaces, Prisons, Hospitals, Barracks, and other buildings, and the Ventilation and Heating of the same; Infectious and Contagious Diseases and Disinfection; Offensive Trades; the Removal and Disposal of Sewage, Refuse and all Waste Matters, and the Disposal of our Dead. These sub-headings are in most cases vast subjects in themselves, and impossible of adequate treatment in a short paper; that, however, with which I intend making an attempt to deal, and that only briefly, is the question of the removal and disposal of Waste Matters.

Having accepted the duty, and decided upon which sub-division of the subject I will write, it becomes my deep concern to consider whether I cannot place before you for your consideration, something new, something important, something which affects the welfare of communities in general, or something which affects this country in particular.

Man in his primitive state had little occasion to worry about Sanitary Science. He alone could not contaminate the air he breathed nor the water he drank, and it does not appear likely that he would attempt to defraud himself by adulterating the food he prepared for his own consumption. He was his own Doctor, his own Architect, his own Local Authority and Sanitary Inspector. With the increase of population, and the formation of small and large communities, an unnatural state of affairs was brought about; unknown diseases appeared, and man in his ignorance could not at first tell what caused them, nor how to cure or prevent them. perience and knowledge, however, have throughout the course of ages taught so much, that it is now possible for thousands of persons to dwell in health and comfort on an area where only tens could have lived in safety in past ages. Complicated questions have been gradually solved by wonderful feats of engineering. Water and food are conveyed to huge communities from long distances, and waste matters are removed therefrom and disposed of in various ingenious ways. These are but a small portion of Sanitary Science.

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It has been written that outside the range of party politics there is no subject on which so much envy, hatred, malice and all uncharitableness prevail as on the treatment of sewage, and this is not difficult to believe when it is discovered that during the forty years ending 1886, four hundred and fifty-four patents were taken out dealing with sewage. What has been the number since I am not in a position to state. To the student of the subject there is considerable interest in tracing the improvements and development in the collection, removal and disposal of sewage during the past fifty

years, and, more particularly, perhaps, in the actual Sanitary Appliances used in and about buildings in connection with what is known as the water carriage system. It is not of this system, however, that I propose writing now, but rather the Dry Earth or Pail System which is so prevalent in this country, and with which so little headway seems to be made, it being recognised more or less as a makeshift system, incapable of improvement, and only tolerated until it can be superseded by a sewerage scheme. But for many years to come, in the smaller inland towns and villages especially, it appears very doubtful, owing to the high price of water, its scarcity, or other local drawbacks, whether what is recognised by many as being the ideal method of sewage removal, will be attained.

Let

It is almost with fear and trembling that I approach the real subject of my paper, lest I be charged with advocating a system which it may be considered should be relegated to the past. it be remembered, however, that it is the improvement of a system that cannot be avoided, that I am urging, and I am doing so having a full knowledge of the many advantages of the water carriage system, and also its disadvantages. I feel that no useful purpose would be served by a long harangue on this latter method. I have no elaborate drawings for you, no bewildering statistics, and no comparisons of costs.

My paper, which has been prepared hurriedly at the last moment under the stress of anxious official duties, shall be so simple in character, that you may deem it scarcely of sufficient merit to be included amongst others that will be delivered before you; but the subject of Sanitary Science was given me, and I selected what I considered to be the most important branch of that Science affecting many inland communities to-day. Should any good result from my directing your thoughts in a certain direction I shall be more than satisfied.

The Pail System for the removal of Night Soil is carried out in the various towns of this country according to the dictates of the Municipalities concerned. In some cases by contract, in others departmentally. At some places large receptacles are in use, being removed once a week, or a fortnight might be allowed to elapse.

At other places quite small pails have been adopted, the removals being effected every 24 or 48 hours. In one important town the work of removal is, I believe, carried out in broad daylight; it is usual, however, to select the dead of night. Sometimes the receptacles are hermetically covered and placed in closed vans, or the contents are discharged into tanks and the empty buckets stacked in a box-like arrangement in the fore-part of the vehicle, as in Kimberley. Take any one of these methods, and I think there is no doubt but that disadvantages predominate. Offensiveness or inconvenience is caused at one stage or another, either through the receptacles being allowed to remain too long on the premises, or during the process of removals, and it is small wonder that the man in the street clamours for reforms.

To my mind, the first reform should be the abolition of the contract system, and all Municipalities should take upon themselves the entire burden of performing this important work, which so closely affects the public health. If a profit can be made from it, that profit should go to the people; if a loss is the result, the people should bear the loss and not a private contractor. If a private contractor can make the work pay where the Municipalities fail, surely there must be something wrong with the Municipal machinery requiring adjustment. There is a certain amount of expert knowledge to be gained from the actual performance of the work, and it appears to me far preferable in the interests of the community that the Municipal authorities should be in full possession of all facts rather than a contractor. Improvements can be far better effected from time to time as occasion may demand under departmental working, and in time of epidemics there is no doubt regarding who should bear the brunt.

As regards other needed reforms, I have already mentioned that offensiveness can be caused either through receptacles being allowed to remain too long on premises, or during the process of removals. In what manner, therefore, can improvements be effected in order that annoyances and discomfort are reduced to a minimum?

Dr. George Ried states, the great principle to keep in mind is the checking of decomposition. . . . Warmth and moisture are the great agents that encourage putrefaction. . . . Dry fæcal matter, comparatively speaking, does not decompose rapidly, but, when mixed with water, or, what is worse, Urine, the change takes place almost immediately.

Many and varied efforts have been made to introduce a suitable closet and system of removal which would meet with the above requirement; Moule's Earth Closet is probably too well known to require description here. Others might be mentioned, but as they do not comply with the principle laid down above, I do not think it necessary to deal with them in this paper.

It is very striking indeed what an improved state of affairs can be brought about by rigidly excluding all liquid, including Urine, from the solid excrement; and, from the moment this is done, it is a comparatively simple matter to deal separately with the Fæces, and Urine, the former being treated as a solid, and the latter as a liquid. It is repulsive, expensive, and unsatisfactory in every way, attempting to dispose of a half-solid, half-liquid mass in such

matters.

I feel convinced that not nearly sufficient earnest attention has been given to this subject. I find that in 1857 F. H. Maberley patented a mechanical arrangement for separating the solid from the liquid portions of sewage, but I know nothing further about his contrivance; probably this was for dealing with a whole town's sewage after having been knocked about through miles of pipes. I also feel that, had the water-carriage system not made the rapid progress, which has been the case during the last sixty years, the

conservancy system would have probably attained a far higher state of perfection.

The late Dr. George Vivian Poore, M.D., Fellow of the Sanitary Institute, was an eminent practical Sanitarian, and deeply considered the question of the satisfactory disposal of all waste matters. He was entirely opposed to sewerage schemes, but his theories were propounded somewhat late in the day. Writing in England in 1893 he states: "Sanitation is a purely agricultural and biological question. It is not an engineering question, and it is not a chemical question, and the more of engineering and chemistry we apply to sanitation the more difficult is the purifying agriculture. This, at least, has been the practical result in this country." There is no doubt whatever, he also states, that whenever excrement is mixed with water we are in danger of Typhoid. Again, if excremental matters be excluded from the house drains, the total volume of sewage to be dealt with would be diminished by at least onefifth, and this surely is a great gain. We should deprive the sewage of just those ingredients which are most troublesome to the sewage farmer by clogging the pores of the ground, and we should leave the sewage very thin and admirably suited to downward filtration. It seems to be an acknowledged fact that, for the application of sewage to land, the more watery it is, and the more completely solid matters are strained out of it, the simpler and more satisfactory the processes become.

Acting on the principles laid down by Dr. Poore, I advised the Kimberley Borough Council about three years ago (and I should here thank His Worship the Mayor for permission to refer to any matters connected with the Borough) to adopt a new system of Latrines at our Native Location, the details for which I supplied.

Prior to the outbreak of Plague in the country, Latrines were non-existent at the Location. At that time, however, a system of Trench Latrines was adopted. This system is disgusting in the extreme, and, in my opinion, more dangerous than the former primitive manner referred to. The problem had to be solved, but a pail service would have cost about £150 per month, and was out of the question on account of the prohibitive cost.

Two Latrines were erected as a trial, being so constructed as to immediately separate the urine from the Fæces. No pails are used; the solids remain on a slightly sloping granolithic floor, and are removed daily and buried, in a dry state, in the top-layers of the soil, in close proximity to the erection. The urine is conveyed from the sloping floor to a granolithic trough, filled with soft wood sawdust, which from time to time is removed and buried, in like manner, when fresh sawdust is supplied. The trial of these Latrines was so satisfactory, that the Council has since decided to erect a sufficient number for the entire Location of about 8000 inhabitants. The cost for cleaning the whole lot has never exceeded 30/- a week; they have never been offensive; by proper daily attention it is an impossibility. Thus by simply separating the liquid