ALL house-refuse of a liquid or semi-liquid character is refuse. It may be called semi-liquid when it has become mingled with any solid substance, though not so fully as to have lost its property of fluidity, its natural power to flow along a suitable inclination.

Wet house-refuse consists of the "slops" of a household. It consists, indeed, of waste water, whether from the supply of the water companies, or from the rain-fall collected on the roofs or yards of the houses; of the "suds" of the washerwomen, and the water used in every department of scouring, cleansing, or cooking. It consists, moreover, of the refuse proceeds from the several factories, dye-houses, &c.; of the blood and other refuse (not devoted to Prussian blue manufacture or sugar refining) from the butchers' slaughter-houses and the knackers' (horse slaughterers') yards; as well as the refuse fluid from all chemical processes, quantities of chemically impregnated water, for example, being pumped, as soon as exhausted, from the tan-pits of into the drains and sewers. From the great hat-manufactories (chiefly also in and other parts of the Borough) there is a constant flow of water mixed with dyes and other substances, to add to the wet refuse of London.

It is evident, then, that the water consumed or wasted in the metropolis must form a portion of the total sum of the wet refuse.

There is, however, the exception of what is used for the watering of gardens, which is absorbed at once by the soil and its vegetable products; we must also exclude such portion of water as is applied to the laying of the road and street dust on dry summer days, and which forms a part of the street mud or "mac" of the scavager's cart, rather than of the sewerage; and we must further deduct the water derived from the street plugs for the supply of the fire-engines, which is consumed or absorbed in the extinction of the flames; as well as the water required for the victualling of ships on the eve of a voyage,

The quantity of water required for the diet, or beverage, or general use of the population; the quantity consumed by the maltsters, distillers, brewers, ginger-beer and soda-water makers, and manufacturing chemists; for the making of tea, coffee, or cocoa; and for drinking at meals (which is often derived from pumps, and not from the supplies of the water companies);—the water which is thus consumed, in a prepared or in a simple state, passes into the wet refuse of the metropolis in another form.

Now, according to reports submitted to Parliament when an improved system of water-supply was under consideration, the daily supply of water to the metropolis is as follows:—

The yearly rain-fall throughout the area of the metropolis is tons, or gallons, feet deep of rain falling on every square inch of London in the course of the year. The yearly total of the water pumped or falling into the metropolis is as follows:—

The reader will find the details of this subject at p. of the present volume. I recapitulate the results here to save the trouble of reference, and briefly to present the question under head.

Of course the rain which ultimately forms a portion of the gross wet refuse of London, can be only such as falls on that part of the metropolitan area which is occupied by buildings or streets. What falls upon fields, gardens, and all open ground, is absorbed by the soil. But a large proportion of the rain falling upon the streets, is either absorbed by the dry dust, or retained in the form of mud; hence that only which falls on the house-tops and yards can be said to contribute largely to the gross quantity of wet refuse poured into the sewers. The streets of London appear to occupy - of the entire metropolitan area, and the houses (estimating as occupying upon an average square yards each) another tithe of the surface. The remaining square miles out of the now included in the Registrar-General's limits (which extend, it should be remembered, to Wandsworth, Lewisham, Bow, and Hampstead), may be said to be made up of suburban gardens, fields, parks, &c., where the rain-water would soak into the earth. We have, then, only -tenths of the gross rain-fall, or gallons, that could possibly appear in the sewers, and calculating - of this to be absorbed by the mud and dust of the streets, we come to the conclusion that the total quantity of rain-water entering the sewers is, in round numbers, gallons per annum.

Reckoning, therefore, gallons to be derived from the annual rain-fall, it appears that the yearly supply of water, from all sources, to be accounted for among the wet houserefuse is, in round numbers, gallons.

The refuse water from the factories need not be calculated separately, as its supply is included in the water mechanically supplied, and the loss from evaporation in boiling, &c., would be perfectly insignificant if deducted from the vast annual supply, but gallons have been allowed for this and other losses.

There is still another source of the supply of wet house-refuse unconnected either with the rain-fall or the mechanical supply of water—I mean such proportion of the blood or other refuse from the butchers' and knackers' premises as is washed into the sewers.

Official returns show that the yearly quantity of animals sold in is—

The blood flowing from a slaughtered bullock, whether killed according to the Christian or the Jewish fashion, amounts, on an average, to quarts; from a sheep, to or quarts; from a pig, quarts; and the same quantity from a calf. The blood from a horse slaughtered in a knackers' yard is about the same as that from a bullock. This blood used to bring far higher prices to the butcher than can be now realized.

In the evidence taken by a Select Committee of the in , concerning Smithfield-market, Mr. Wyld, of the Fox and Knot-yard, , stated that he slaughtered about cattle weekly. "We have a sort of well made in the slaughterhouse," he said, "which receives the blood. I receive about a week for it; it goes twice a day to Mr. Ton's, at . We used to receive a good deal more for it." Even the market for blood at Mr. Ton's, is, I am informed, now done away with. He was a manufacturer of artificial manure, a preparation of night-soil, blood, &c., baked in what may be called "cakes," and exported chiefly to our sugargrowing colonies, for manure. His manure yard has been suppressed.

I am assured, on the authority of experienced butchers, that at the present time fully threefourths of the blood from the animals slaughtered in London becomes a component part of the wet refuse I treat of, being washed into the sewers.

Now, reckoning only -fourths of the blood from the cattle slaughtered in the metropolis, to find its way into the sewers, we have, according to the numbers above given, the following yearly supply:—

This is merely the blood from the animals sold in Smithfield-market, the lambs not being included in the return; while a great many pigs and calves are slaughtered by the London tradesmen, without their having been shown in .

The ordure from a slaughtered bullock is, on an average, from to cwt. Many beasts yield cwt.; and cows "killed full of grass," as much as cwt. Of this excrementitious matter, I am informed, about a part is washed into the sewers. In sheep, calves, and pigs, however, there is very little ordure when slaughtered, only or lbs. in each as an average.

Of the number of horses killed there is no official or published account. man familiar with the subject calculated it at weekly. the blood from the knackers' yards is, I am told, washed into the sewers; consequently its yearly amount will be gallons.

But even this is not the whole of the wet houserefuse of London.

There are, in addition, the excreta of the inhabitants of the houses. These are said to average lb. daily per head, including men, women, and children.

It is estimated by Bousingault, and confirmed by Liebig, that each individual produces lb. of solid excrement and lb. of liquid excrement per day, making lb. each, or lbs. per individuals, of semi-liquid refuse from the watercloset. "But," says the Surveyor of the Metropolitan Commission of Sewers, "there is other refuse resulting from culinary operations, to be conveyed through the drains, and the whole may be about lbs. for persons."

The more fluid part of this refuse, however, is included in the quantity of water before given, so that there remains only the more solid excrementitious matter to add to the previous total. This, then, is lb. daily and individually; or from the metropolitan population of nearly a daily supply of lbs., rather more than tons; and a yearly aggregate for the whole metropolis of lbs., or very nearly about tons.

From the foregoing account, then, the following is shown to be

Hence we may conclude that the more fluid portion of the wet house-refuse of London amounts to gallons per annum; and that altogether it weighs, in round numbers, about lbs., or tons.

As these refuse products are not so much matters of trade or sale as other commodities, of course less attention has been given to them, in the commercial attributes of weight and admeasurement. I will endeavour, however, to present an uniform table of the whole great mass of metropolitan wet house-refuse in cubic inches.

The imperial standard gallon is of the capacity of . cubic inches; and estimating the solid excrement spoken of as the ordinary weight of earth, or of the soil of the land, at cubic feet the ton, we have the following result, calculating in round numbers:—

Thus, by this process of admeasurement, we find the

Figures best show the extent of this refuse, "inexpressible" to common appreciation "by numbers that have name."

[] In East and West London there are rather more than 32 houses to the acre, which gives an average of 151 square yards to each dwelling, so that, allowing the streets here to occupy one-third of the area, we have 100 square yards for the space covered by each house. In Lewisham, Hampstead, and Wandsworth, there is not one house to the acre. The average number of houses per acre throughout London is 4.