Millions from Waste by Frederick Arthur Ambrose Talbot - HTML preview

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CHAPTER IX
 SUPPLYING INDUSTRIES FROM THE DUST-BIN

During the past few years no effort has been spared to improve the health and well-being of the community. Laws innumerable have been passed compelling the mitigation of nuisances and the removal of menaces to hygiene. These efforts are laudable, but, while they have achieved the desired end, they have been directly responsible for many other shortcomings. The greatest of these is waste, more especially in so far as it affects the household.

Probably no other factor has contributed so materially towards the factor of heavier domestic prodigality than the provision of the portable dust-bin, and the introduction of systematic and regular collection of the flotsam and jetsam contributed thereto. The very convenience which the dust-bin or ash-barrel represents has served to accentuate household extravagance. “Throw it in the dust-bin!” is the popular slogan in domestic circles. Consequently this receptacle has become the harbour for much domestic refuse which, under previous conditions, would never have been so summarily discarded.

This disposition to be wasteful might have been checked, or at least the errors of the domestic circle might have been rectified very considerably, but for one disturbing element. We became such devout worshippers of hygiene as to become insensible to all reasoning. A few years ago the practice was to discharge the contents of the ash-barrel upon open waste land. A small army of workers, even the nomadic element of the community, turned to and raked over the spoil from our homes very diligently. In this way immense quantities of odds and ends in infinite variety which otherwise would have been lost found a market as raw materials for many industries. Even the ultimate organic residue fulfilled a mission of utility and one in consonance with the laws of Nature, because, in the process of decomposition, the nitrogen and phosphoric acid contents of the dump suffered release to feed the soil to raise sustenance for man and beast.

But ransacking the garbage heap was declared to be a degrading and health-menacing occupation and practice. Indeed, the whole system of household refuse disposal was held up to obloquy. Reform was achieved by the energetic advocacy of another means wherewith to cope with such waste. It received widespread support because it fully coincided with all the requirements of hygiene, while, furthermore, it was simple, expeditious, effective and apparently cheap.

This was destruction by fire along so-called scientific lines. The new idea arrested public fancy mainly for the reason that its champions laid emphasis upon the fact that it presented the possibility of obtaining energy to generate electric light and power and to drive tramways for nothing. Municipalities became affected with the incineration fever. Steam was necessary to drive the electric plant which had been acquired. Why not cut down the coal-bill by making use of the fuel properties possessed by household refuse? The contents of the domestic dust-bin are so varied, ranging from waste-paper, grease-laden bones, fragments of fat, cinders, rags and vegetable odds and ends as to present, in the aggregate, a readily combustible mass possessing distinct calorific value. By utilizing the garbage, which has to be collected, in this manner, the coal-bill might be reduced by so much.

So argued the advocates of the new idea, and their reasonings proved so specious as to gain the day. The prospect of being able to get “Something for nothing” was so alluring as to silence effectively all adverse criticism. Of course, it was futile to gainsay that cremation could be rivalled as a prompt, simple, and completely sanitary means of coping with the refuse which accumulates in every city and big town. Forthwith destruction by fire became the widely-accepted means of getting rid of the unsightly and unsavoury contents of the dust-bin.

Yet the coming of the dust-destructor proved to be a distinctly retrograde step in the science of economics. It contributed to increased improvidence in the home, because the ash-barrel became the receptacle for a still wider assortment of organic material than ever before, and in greater bulk.

It must be conceded that not all of the garbage which suffered this fate was destroyed to futility. A certain volume of steam was certainly raised wherewith to drive the electric generators, but the amount of energy obtained in this way was out of all proportion to the quantity and value of the material incinerated. In certain cases the destructor was not harnessed to the power station. The ratepayers have not experienced any sensible relief in regard to the fuel bills. Even incineration of household refuse, despite the proportion of its combustible contents, cannot be conducted satisfactorily without the consumption of a certain volume of coal. And the process precipitates a certain quantity of further refuse, in the form of clinker and ash, the economic disposal of which has provoked another and even more perplexing problem.

When necessity, which knows no law, compelled us to economize in every direction, and particularly in connection with food, we found it expedient to turn round to ascertain whether or not we might be able to effect tangible savings to minimize the disconcerting influences of stringency. The domestic dust-bin was the first factor in the domestic circle to undergo sensational overhaul. Material which had hitherto been consigned to this dead end only too freely and perfunctorily, was more closely scrutinized to see if it could not be induced to yield further useful service before suffering complete abandonment by the housewife. Contemporaneously with this manifestation of individual private effort the civic and municipal authorities were compelled to display unwonted activity. The whole problem of refuse disposal had to be viewed from quite a new angle.

Upon investigating the issue of household refuse at close quarters, and under the microscope of concentrated interest, the country’s wastage in this direction was found to exceed the wildest speculations of the critics. For the first time illuminating statistics became available. According to the National Salvage Council, the official department created to stimulate the public mind in matters pertaining to this question, the quantity of refuse “made” by householders throughout the country during the year may be set down at 9,450,000 tons.

At first sight this figure seems so startling as to be received with incredulity, but analysis suffices to demonstrate that it does not err upon the side of exaggeration. Rather is it conservative. It is based upon an allowance of 1,680 lb. a day for each 1,000 members of the total population during 300 days of the year. An allowance of 1·68 lb. per head per day wastage cannot be construed as excessive. How many households of six persons can show a weekly dust-bin collection weighing less than 60 lb. especially when the extremely varied contents of the receptacle are born in mind?

Now, of what is the heterogeneous collection of the dust-bin composed, and what is the proportion of each to the aggregate? The following table, based upon the data collected by the official department already mentioned, shows—

Material.

Average Percentage.

Total per Year.

Estimated Value.

 

 

 

Tons.

£

$

Fine dust

50·98

4,800,000

240,000

1,200,000

Cinders

39·63

3,700,000

1,850,000

9,250,000

Bricks, pots, shales, etc.

5·35

500,000

25,000

125,000

Tins

0·98

90,000

360,000

1,800,000

Rags

0·40

37,000

555,000

2,775,000

Glass

0·61

50,000

100,000

500,000

Bones

0·05

4,000

Vegetable matter

0·72

68,000

Scrap iron

0·06

5,000

15,000

75,000

Shells (oyster, etc.)

0·08

7,000

Paper

0·62

58,000

400,000

2,000,000

From these figures it is evident that the dust-bin is a veritable treasure ground. Of course the values are subject to market fluctuations, but it is apparent that a round £3,000,000—$15,000,000—more or less, a year, is being allowed to fly up the chimney to vanish in smoke and gases, and to extend very meagre return for its combustion.

Let us consider the despised homely cinders as an illustration of how we permit wicked waste to reign in the household circle. According to the table they represent approximately two-fifths of the total contents of the dust-bin, and make up the respectable aggregate of 3,700,000 tons a year for the whole country. As a straight fuel the cinder is but slightly inferior to coal. When washed its calorific value is about 10,000 British Thermal Units. Good steam coal only averages 14,000 British Thermal Units. Accordingly the spurned cinder, from the heat-raising point of view, is worth about five-sevenths of coal drawn fresh from the mines. The householders of Britain have been content to throw away 37,000,000,000 British Thermal Units every year in ignorance. Translated into terms of coal this is equivalent to 2,642,857 tons. In other words we have wasted what is tantamount to two-and-a-half millions of high-grade coal every year, and have spent money on fuel which we might just as well have kept in our pockets or have turned to other beneficial purposes. Obviously, if every house undertook to turn its cinders to full account, the domestic call upon the mines might be materially reduced, while there would be an appreciable contribution to the conservation of our coal resources from such a practice.

Paper is another commodity which, in the past, we have handled along woefully improvident lines, as related in the previous chapter. We have not even taken the trouble to burn it, but have permitted it to drift and flutter hither and thither to find a final repository, grievously soiled and dirty, in the dust-bin. But even when so marred and deteriorated it was worth, during the war period, no less than £7—$35—a ton!

The wastage of rags, both cotton and woollen, has been even more deplorable. In this instance, however, possibly a reasonable excuse for the prompt consignment of such material to the dust-bin and the dust-destructor can be advanced. Popular opinion regards textile odds and ends as an ideal vehicle for the transmission of the germs of disease. Yet such does not justify the indiscriminate committal of material worth £15—$75—per ton to incineration. Infected rags should be burned forthwith in the household fire. But are they? Investigation would probably reveal the disconcerting fact that they are thrown into the dust-bin, as offering the most convenient means of disposal. Even if they should be above suspicion when discarded, the chances are that they become contaminated in the ash-barrel. Consequently upon recovery such materials should be subjected to preliminary inexpensive sterilization to ensure the public safety.

When the necessity to practise household salvage upon a comprehensive scale became imperative, a few discreet inquiries were made to secure reliable statistics as to what wealth is ignored or thrown away by the community of these islands. The results were somewhat surprising.

In Sheffield, a city of some 500,000 persons, 56,000 jam-jars were recovered in one week through a special collection conducted by school children. They realized 6 shillings—$1.50—a gross, and so brought in £120—$600. In Leicester the practice is, or was, to dispose of certain articles to the local marine store dealers after collection, and to divide the profit arising from the transaction among the employees engaged in the refuse-gathering task. One quarter’s waste, exclusive of old tins and waste-paper, netted £343—$1,715—of which £249—$1,245—was obtained from rags alone. There were 264 dozen jam-jars collected. They cost 15s.—$3.75—a gross new, and the trade expressed its readiness to take over the reclaimed vessels at 7s. 6d.—$1.87—a gross. Kensington made £1,000—$5,000—from the sale of one year’s collection of waste-paper. The Southport authorities recovered £2,000—$10,000—over a similar transaction. The metropolitan boroughs of Finsbury and Marylebone each swelled its local treasury to the extent of £500—$2,500—in a similar manner. The City of London garners 30 tons of this commodity every week. The ink-bottles recovered from the garbage barrels of the metropolis would provide a person with a comfortable income, averaging as they do several gross a day. Liverpool derives £300—$1,500—from house-swill alone, which it collects, dries, and turns into poultry-meal to sell at £15—$75—a ton. Aberdeen, as the result of one day’s organized collection, secured sufficient bottles to realize £567—$2,835.

It is obvious that, no matter from what point of view the question is regarded, systematic organized salvage of the contents of the household dust-bin can be rendered a highly profitable enterprise. Certainly it opens up a promisingly rich and legitimate field for municipal trading, though it is equally accessible to private initiative. It is only requisite to survey the whole situation of the disposal of house garbage from the new angle of scientific application. It is not refuse in the generally accepted interpretation of the term. Such material should rightly be regarded as by-products of the private domestic kitchen.

The tardy recognition of this fact is responsible for a curious reversion in practice. The open-air sifting of house refuse for the recovery of substances possessed of commercial value was unequivocably condemned from health motives, as previously mentioned. Yet, in order to recover these articles, some system of selection and hand manipulation are inevitable, notwithstanding the high degree of intellectuality to which machinery has been advanced. But the old system of hand-picking was primitive in its simplicity. The circumstance that household refuse, both organic and inorganic, possesses virtues which the vogue of the destructor caused to be blindly ignored, has been responsible for a manifestation of marked ingenuity upon the part of the engineering profession. The necessity to recover every ounce of material possessing a market value was never so acute as it is to-day. Supplies are short and are likely to remain inadequate for some time to come, while the high level of prices is apt to compel more rigid economy. Yet the strains encountered in this direction may be very sensibly lessened by the practice of salvage along more intensive lines.

It would seem as if refuse recovery were destined to develop into a highly specialized branch of the engineering craft. Hitherto for the most part the engineer has confined his efforts towards garbage-disposal by destruction, but the new tendency is far more logical and deserving of every encouragement. Certainly it is a field in which abundant scope is offered for brilliancy and ingenuity of thought. This is demonstrated by the activity of certain firms, more particularly of one in the North of England, the guiding hand of the destinies of which has evolved a complete recovery plant, having many decidedly ingenious features, and which is already being installed by certain of our more progressive corporations and municipal authorities.

This plant is self-contained, and, so far as is feasible, is automatically operated. While hand-picking cannot be entirely eliminated it has been reduced to the minimum. The system adopted facilitates the task, and renders hand-picking as congenial as the peculiar conditions will permit. Furthermore it is an individual entity. While it can be established in an isolated centre it can also be coupled up to the existing dust-destructor, or power-generating station if preferred, thereby complying with the general desire to centralize municipally-controlled installations. This is certainly a powerful recommendation, because it avoids superfluous transport and handling.

Under this scheme the refuse-collecting vehicles discharge their loads into a receiving hopper from which the material falls by gravitation into a hexagonally-shaped revolving riddle. This screen or reel for two-thirds of its length is perforated to allow the fine ash associated with the waste to escape into another large hopper placed immediately beneath. The ash may then either be withdrawn directly from this hopper into wagons or carts for removal, or should arrangements be made for its combination with other ingredients to produce a fertilizing agent, it may be led by conveyor from the hopper to the compounding-room.

For the remaining third of its length the hexagonal revolving screen is perforated with a coarser mesh to permit the cinders to escape into a separate hopper, at the base of which is a worm conveyor which receives the cinders and bears them to a washer. The washing operation is introduced to allow the separation of the light or combustible fuel—cinders—from the heavier clinker, fragments of glass, pottery, and other incombustible substances. At the same time all fine dust clogging the interstices or pores of the cinders is removed, thereby facilitating the subsequent combustion of the cinder, while, of course, the heat produced from the cleansed fuel is greater than that derived from such material loaded with incombustible dust.

After being washed the cinders are picked up by a scraper elevator. If it be intended to utilize this fuel for raising steam in the adjacent power plant it can be carried by conveyor direct to the boiler-room, to be discharged into the bunkers or furnaces. Should it be decided to dispose of the cinders, either wholly or in part, to the general public, they may be taken by the transporter to any suitable point to be stored against sale in bulk or in bags.

A second scraper elevator gathers the heavier debris separated from the combustible fuel in the washer, and carries it to a pulverizer, to which it is delivered through a chute. If the fine dust associated with the raw refuse, and which fell through the receiving screen, be not delivered from its hopper into vehicles for immediate disposal, it may be led to this point to be stored in the pit receiving the material from the pulverizer with which it may be mixed. Of course, the dust is not passed through the grinding plant.

The elimination of the dust and coarser material from the crude garbage in the receiving screen leaves an appreciable quantity of organic and inorganic matter, comprising such divers substances as paper, fragments of wood, bottles, jars, bones, tins, and vegetable material to be handled. As these cannot pass through the perforations in the sifting screen they are delivered on to a broad endless conveyor-belt travelling between two platforms. This is the “picking belt,” from the fact that as the material is borne along between the two platforms the useful material is removed by the hands of pickers, to be cast into suitably disposed bins. In this manner the process of segregation is carried out with the minimum of effort, while the material is in movement, and under the most congenial conditions the character of the work will permit. It represents the only stage at which recourse to manual labour is required, so that it will be seen that hand-selection is reduced to the absolute minimum.

The waste-paper is not touched by hand. At a suitable point a specially designed hood, connected to an exhauster, is mounted over the picking belt. When this is set in motion the induced draught is sufficiently powerful to suck up the paper, and to bear it through a special conduit to be discharged into a convenient receptacle, whence it may be removed to the baling press.

This plant, known as the Hoyle refuse-recovery installation, after its inventor and designer, Mr. H. P. Hoyle, is extremely efficient. Simplicity is the outstanding feature, while its operation is economical and requires only the minimum of labour. So far as power is concerned a single 10 horse-power electric motor suffices for all operations. The capital cost has also been kept down, the price of the complete plant being from £1,500 to £2,000—$7,500 to $10,000. At this figure the installation of the system should prove distinctly profitable, more especially in conjunction with one or two auxiliary appliances which offer the means to enhance the market value of the recovered materials, although they are not essential. For instance, an appreciable proportion of the tins thrown into the dust-bin are in a bright condition and free from rust. Such tins can be made to yield so much crude tin plate for the production of further tins, instead of being subjected to the less economic process of crushing, baling, and detinning or transference to the furnaces in billet form to be melted down.

A special type of machine has been evolved whereby the tops and bottoms of the bright recovered tins can be cut off. The resultant cylinder is then cut through on either side of the original seam, and the sheet pressed out to form a flat plate. The eliminated joint, of course, is set on one side to be treated for the recovery of the solder, while the small pieces of tin find their way to the scrap-metal bin. The sheets of bright tin which are thus recovered, and which are quite equal to new tin-plate, command a ready sale, because they can be restamped into smaller flat tins for packing boot polishes and similar commodities extensively retailed in this form. The process is simple, rapid, and can be made profitable.

Rusted tins require to be treated in a different manner. Some corporations merely crush them flat to facilitate and to cheapen transport, selling them in bulk to firms who specialize in the handling of such product. However, it is a matter for investigation, when such tins are recoverable from the garbage in appreciable quantities, as to whether it would not prove more remunerative to the local authorities to deal with the tins themselves. A furnace is required to burn off the tin-dirt and to recover the solder. The tin itself, representing about 1 per cent., is lost, although there are processes in operation for its reclamation. The receptacles may then be crushed and baled into billets for which an hydraulic press is necessary. A plant capable of making a bale measuring 24 × 14 × 6 inches is well-adapted to this duty. The solder is in demand, while the plate is worth from £3—$15—upwards per ton as scrap metal. At this figure the local authorities would undoubtedly find it far more profitable to incur the extra expense and labour involved to prepare the billets rather than to dispose of the tins in their crude form. When the quantity is heavy direct sale to the steel-works is possible and the middleman’s profit diverted to the benefit of the ratepayers.

Paper should also be baled for reasons of transport. Either hand or power appliances may be used, but unless the quantity likely to be handled is pronounced, the hand-operated machine will be found adequate for the task. Of course, it must be admitted that, to-day, prices for the recovered materials rule somewhat high. Consequently it may be averred by critics that, whereas such auxiliaries might be perfectly justifiable under conditions such as now prevail, they would fail to show an equally satisfactory result in normal circumstances.

But it must not be forgotten that prices are steadily rising all round. Accepted raw materials are costing more, labour is more expensive, and the tendency in both directions is still in the ascendant. But even should prices and costs droop, it must not be forgotten that such a movement would be attended by the utilization of greater quantities of the articles concerned. They would be recoverable from the garbage in greater volume, and then it would be possible to keep the plants running to their full capacities for no heavier operative or overhead costs. Consequently, in the long run the disposal of enhanced quantities of tins, either as “bright” or scrap, at a lower figure, would probably prove more profitable in the aggregate than treating a limited supply, such as obtains under stringent economic conditions, at a high figure.

How does a recovery plant of the foregoing description work out in practice? This is the vital question. Upon this point it is possible to advance some interesting figures. An investigation of the domestic refuse problem as it affects the country as a whole has revealed the circumstance of the contents of the dust-bin being tolerably consistent, whether it be drawn from a residential or manufacturing town, from the East-end or from the West-end, from the city or from the suburb. On the basis of the analysis set forth elsewhere in this chapter, and taking for our illustration a metropolitan suburb having a population of 85,000 souls contributing 100 tons of refuse a day, the possible recovery of by-products comes out as follows:—

 

Material.

Tons per Day.

Price per Ton.

 

Total Value.

 

Fertilizer prepared from fine dust and pulverized
 debris from washer and picking belt

 

£ s. d.

$

£ s. d.

$

65

0 1 0

0.25

3 5 0

16.25

Cinders

25

0 10 0

2.50

12 10 0

62.50

Tins and metal

2

4 0 0

20.00

8 0 0

40.00

Paper (unsorted, dirty)

1

7 0 0

35.00

7 0 0

35.00

Rags

0·5

15 0 0

75.00

7 10 0

37.50

Glass

0·5

2 0 0

10.00

1 0 0

5.00

Gross total per day

 

 

 

£39 5 0

$196.25

The foregoing figures may be accepted as moderate. Thus the cinders, with a heating value equal to five-sevenths of that of good steam coal, are priced at 10s.—$2.50—per ton. But, as experience has proved, they readily command 14s.—$3.50—per ton, providing, in their washed condition, a first-class, clean, cheap and economical fuel for the poorer classes of the community. At 10s.—$2.50—per ton they are equal to coal costing 14s.—$3.50—per ton, at which price such fuel is absolutely impossible to-day. Even coke cannot be purchased at double the figure. In other words, by buying washed cinders at the prices quoted the purchaser is receiving a fuel equal, if not superior, to contemporary household coal costing 35s. to 50s.—$7 to $10—per ton.

Again, the tins are assessed at a low scrap-metal value. Probably 50 per cent. of the tins rescued from the dust-bin to-day coincide with the term “bright,” and thus would pay to turn into tin-plate. The quotation for this material ignores the value of the solder, as well as that ruling for other metals, such as brass and copper, and of which far more is recovered from the ash-barrel than may be popularly imagined. The figure given, moreover, represents the official price, but since the removal of control scrap-metal has recorded higher quotations. So far as the other materials are concerned the prices may be taken as representative.

On the above showing of £39 5s.—$196.25—per day the plant gives a gross return, in round figures, of £235—$1,175—for a six-day week, or £11,775—$58,875—for a 300-day year. Allowing £5,000—$25,000—a liberal figure—for the annual operation of the plant, the sum of £6,775—$33,875—remains—the net return from the realization of some of the utilitarian material recovered from the dust-bins into which 85,000 people throw what they consider to be useless during the course of the year. Truly may it be said that the average member of the public has but little, if any, idea of the wealth he allows to slip through his hands as a result of carelessness or lack of knowledge. Again, when it is reflected that, for the most part, the whole of such potential wealth as this has been permitted to vanish in smoke, or if incombustible to be kicked from pillar to post, we certainly cannot complain when accused of deplorable extravagance.

So far as the capital expenditure of a plant, such as is set forth above, is concerned, this may be set down at £1,000 to £1,500—$5,000 to $7,500. If for such a paltry expenditure a net revenue of £6,775—$33,875—can be secured during the course of the year, surely the moment has arrived when we ought to put our civic and municipal houses in order. Granting that prices to-day are abnormal, and reducing the net return by 50 per cent., even at £3,387—$16,935—per annum, which may be taken as a safe assumption, a plant of this description is able to pay its way within a short time after its installation, after making even the most liberal allowances for capital charges, interest, and depreciation.

The Hoyle system is one which should make a powerful appeal to the small communities, which, at the moment, are deficient in any system of garbage disposal other than open dumping. It has the governing virtue of being extremely flexible, being as readily applicable to the small town, numbering only a few thousand—even hundreds—of inhabitants as to the teeming city of a million or more souls. The financial outlay involved is comparatively trivial for the results achieved, and varies according to the size, capacity, and completeness of the plant.

Should our smaller towns embrace the system the contributions to the searching problems of the moment would, in the aggregate, be decidedly startling. The materials thus recovered, turned into the proper channels, would go a long way towards relieving the strains which are being experienced. The small town has a golden opportunity to demonstrate to the larger communities how things should be done. For the most part it is not saddled with a costly, so-called hygienic, destructor. The science of turning the contents of the dust-bin to commercial advantage is one offering possibilities too numerous to mention and might even lead to the establishment of local industries. Nothing organic or inorganic possessed of any utilitarian value need be lost.

On the other hand the city is not in such a fortunate position. It will have to forget a good deal of what it has assimilated in connection with the disposal of the contents of the ash-barrel. A change-over from the old to the new method must inevitably occupy time, especially as those two dragging chains which always retard the march of progress—prejudice and conservatism—have first to be released. Nevertheless, as destruction of domestic waste by fire superseded dumping upon open land, so must incineration, in turn, give way to the latest demands of science and the immutable economic law. The dust destructor never could possibly be construed into a scientific solution of the problem: it has no constructional or creative value, except of a nuisance in the form of accumulations of clinker. Even primitive dumping upon the land did possess the distinct advantage of benefiting the soil over which it was distributed. When the latest idea for recovering and exploiting the by-products of the dust-bin achieves the vogue which it deserves, land and industry will profit to the benefit of the community and of the country.

Naturally, certain local authorities, notoriously opposed to progressive development, will seek to stop the tide by belittling the new policy. They have become so firmly wedded to the destructor in which so much of the ratepayers’ money has been sunk as to be blind to improvement. They will continue still to waste money in supporting their fetish, strenuously declining to honour the axiom that it is often cheaper to cut the loss.

In the absence of willingness to jettison the old and to adopt the new, the pressure of compulsion should be applied. Local authorities must be prevented from continuing to squander potential resources of raw material. Alternatively, the exploitation of the despised dust-bin should be brought within the reach of private enterprise, which should be extended every encouragement. Other nations have always regarded our much-vaunted dust destructor as the high-road to waste. It has never found any pronounced favour beyond the confines of Britain. Have our rivals been wiser than we?

An interesting commentary upon this somewhat inexplicable predisposition to destruction by fire is offered by the experience of the city of San Francisco. In 1896 the city granted a fifty years’ franchise for the provision of a destructor for the disposal of household refuse to a private party. “This destructor,” remarks the city engineer in a communication to myself, “is the second, and last, example of the Thackery furnace and arrangement, the first having been built in Montreal, Canada, the previous year (1895).”

This plant has passed through somewhat strange vicissitudes. In 1910 it was purchased, together with the franchise, by the city authorities for £70,000—$350,000. It was then leased to a private party, under privilege, in return for an annual payment of £3,700—$18,500—5 per cent. upon the purchase price. During the early months of 1918, owing to the great increase in wages and other costs of operation, the lessee relinquished his lease, so that it was thrown back upon the hands of the city authorities. It was then taken in hand by the Scavengers’ Association under permit from the city, by whom it is at present being run at a cost of about 4s.—$1—a ton for the 375 to 380 tons of refuse collected daily by the scavengers.

But the city authorities are not impressed with this method of disposing of the contents of the ash-barrels of its citizens. “During the past year or two,” continues the city engineer in the communication already quoted, “we have become more than ever impressed with the wrong of unnecessary waste and have been making special study of our conditions and the means of improving them. Ordinances for segregation at the source, and collection of all, both garbage and rubbish, are now under action by the Board of Supervisors—the governing body of the city—and specifications are being prepared and bids asked upon the same for the collection and disposal of garbage and rubbish.

“It is specially provided that all proposals shall be based on a recognition of the need of conservation and the recovery of all values to the point of balance between profit and loss. It is expected that the garbage from households will amount to upwards of 100 tons daily, and that it will be attractive to hog-raisers.”