IMPORTANT RUBBISH.

Nelson Examiner and New Zealand Chronicle, Volume XIV, 1 December 1855, Page 3

IMPORTANT RUBBISH.

[From the Household Words] We have in one of our former numbers shown how art and science have been brought to bear upon things before thonght worthless : how the refuse of tbe smithy, the gas-woiks, and the slaughter- house, have been made to yield products the most valuable, results ihe most beautiful. We are now about to relate how another useful step has been made in our Penny Wisdom. The iron w-alth of England is a proverb in the moat remote corners of the world. It produces the enormous amount of three millions of tons annually. We export to nil parts of the world iron and steel to tbe yearly value of ten millions sterling, and machinery and tools to the extent of two millions— Bura9 that equal the revenue of more than one kingdom. In travelling throush the iron districts of England it is impossible to avoid being struck with the vastnpss of the works carried on in those places. A journey through our mining districts— where undying flames leap forth from hundreds of volcanoes, and around which nothing i 9 discoverable but blackened piles or cinders, and unsightly slag— will not be easily forgotten. For scores and scores of miles the traveller beholds thesie apparently interminable heaps of refuse ore. Carts, waggons, Bnd trucks may he seen on all sides, occupied in the endless task of removing this metallic incumbrance of the smelting works.

Hundreds of labourers are engaged in conveying to remote and undisturbed spots tbe enormous piles of black, friable, clinkerv looking stuff— the slag that day by day and hour by hour is produced by the smelters of iron ore. Some is flung down deep gullies, and hidden in the dazk, yawning, recesses of ravines, when haply any such are to be found. Someisemployed in the hardening of rotten road- ways, where it is made to perform a very unsatisfactory fort of duty for stone. Occasionally it is shot into the sea, when near enough for that purpose, which however is not often the case. Of the actual extent of this rubbish production some idea may be formed when it is stated, as it has been, on very good authority, that in tbe removal of all this waste slag from the furnacemouths of the United Kingdom, not much less than half-a-million steiling is annually expended. Indeed, it has been calculated that in round numbers there are at the present time fully six millions of tons of this refuse material produced in one year. At this rate it would be easy to imagine the gullies, pits and ravines of the iron districts becoming filled up at no very remote period, when iron master* would have to go further in search of secluded spots whereon rubbish might be phot.

The- philosopher who by the aid of scientific observation and research can point out to us how to turn all this perplexing mass of unproductive refuse to good and profitable account — how by a sirai le method we may convert this ugly, useless clinker into a beautiful means of ornamentation, and make it an indistructihle and economical agent in tbe construction of public works and dwelling- houses — purely the man who can accomplish this deserves some thanks at our hands. All this has been accomplished by the patient research of Dr. W. 11. Smith, of Philadelphia, United States, who recently delivered a lecture on the subject to the members of our Society of Arts. In this interesting discourse, the lecturer pointed out the brittle and useless character of the mineral refuse of smelting furnaces, at present known under the name of slag. A careful analysis of this hitherto rejected product of our iron woiks shows that it is composed, in the tnain, of lime, Rilica, and alumina, with an occasional admixture of magnesia and sulphur. In all parts of the world the same results are arrived at. The slag of France or Sweden differs in no essentials from that of Britain or the United States. It is scarcely necessary to remind the reader of tbe similarity in the process of smelting or.es, and the vast operations of nature beneath the crust of the earth, where, by a like agency of heat, mountain our deposits of igneous rocks are constantly thrown off.

The rocks of this origin are met with in stupendous masnps in most parts of the world. While nature on the one hand employs her igneous products in the construction of gigantic mountain-palaces, man, well aware of their great value, equally applies those rocks, under the names ot granite, feldspar, basalt, greenstone, syenite, porphyry, serpentine, &<•„ in tbe construction of his most elaborated architectural edifices. High geological authorities tell us that if we examine the composition of the crust of the globe, we shall find that of all the earths and earthy substances therein, three only will be ascertained to constitute its great bulk, namely, silica, alumina, and lime — precisely those which mainly compose the slag of the smelting- house.

The worker in ore», when he is occupied with his blast-furnace is, in fact, but repeating on a small scale the grandest operations of nature deep in the bowels of the earth. Heat is tbe great first agency employed by nature and by tbe philosopher in tbe decomposition and re-com-bination which produce some of the most beautiful and useful products with which we are acquainted. Dr. Smith has shown that tbe rubbish of the smelting house is identical in character, and equally valuable, with most of the igneous rocky substances.

Liko many other valuable discoveries, this result was arrived at while searching for something else. It is well to relate how this truth, so interesting in itself, apart from commercihl result**, was seized upon by the American philosopher, since it may tend to encourage such as may be toiling in other fields of research. Impressed with the conviction of the influence of electricity upon life, health, and discaftP, Dr. Smith, at that time a practitioner in Philadelphia, commenced a series of experiments in electro-agencies on the human frame. Success in that question induced him to carry his researches to vegetable life, and from animate he was led to direct his observations to inanimate object*. Mineral matter received attention from him, and, weighing well the geological facts alluded to above, Dr. Smith bent the energies of his mind to trace the effects of electricity in all these combinations and reproductions.

Comparing tbe condition and character of slag with that of the igneous tocks of nature, be felt that to electric agency must he attributed the cause of the great difference existing between them. In order to test this, he took a piece of the vitrified mass of slag, hot from the furnace mouth, and applied it to a metallic rod. At the point where this electric conductor came in contact with the substance, the vitrified mass assumed b pulverulent character; sevpral rods were employed, and at each point of contact similar changes in the condition of the Mag were ohservable. The electricity rapidly engendered during tbe smelting process, was parted with as quickly on the application of the metal conductors, and hence the sudden and marked change in tt.e condition of the mineral.

In order more fully to test this theory, the experimenter threw a quantity of the molten tUg fresh from the furnace- mouth into water. Every atom of the liquid being a good conductor of electricity, rapidly absorbed it as it lowered the temperature of the mass; and the immediate consequence was, th;t tbe mineral matter fell into a course powder, entirely deprived of its former cohesion or solidity.

From these trials, Dr. Smith felt convinced that his electrical theory waß correct, and that it wp.s to the rapid giving forth of its electricity by sudden cooling in contact wi;h conducting media, that

i lajj owed its brittle character— in other word*, its want of cohesion and its tendency to pulverise. He reflected that the great masses of igneous rocks upheaved from the centre of hpat, were in a position for gradually cooling; their gigantic extent would ensure that result— hence their extreme hardness ard durability.

With a view of completely testing tbe accuracy of his electrical theory, Dr. Smith caused a quantity of Flag fresh from tbe smelting furnace to flow upon a non conducting substance, where it was allowed to cool much more gradually than was usually the case. To his great delight, he found that he had obtained a roost complete verification of his opinion. The product thus obtained, had entirely lost its eemivitrious and friahle character, and assumed a dense, solid, and rocky nature, capable of resisting the heaviest blows, Bnd altogether assuming the peculiarities of the igneous rock*. Having obtained this result, the experimenter proceeded to other trials. By continuing the molten flag, when removed from the furnace nt a high Jtemuprature in an oven, where it was afterwards allowed to cool very gradually, and then run into moulds of a non-conducting substance, tha material was found to have become altogether de-vetrified, and to have taken a beautifully veined and granulated character of extreme hardness, approaching to the solidity end strength of tha finest marble. By varying tbe heat applied, by the admixture of colouring matters, and by a subsequent polish applied to tbe surface, the experimenter baR succeeded in producing a perfect imitation of cornelian, ogate, malachite, or any other of the more vtluable mineral productP.

Here then we see how an inquiry, having for its object the elucidation of a purely scientific theory, has led the inquirer by imperceptible stepß to « moßt valuable discovery, by means of which, many millions of tons of hitherto refuse- matter, may be converted into really useful and valuable materials for the builder, the architect, and the dtCorator.

Already, in America, the slag of iron furnaces, in its new character, is employed for paving purposes wiih the most complete success — whole thoroughfares having been for several years laid down with this material without any percentibe wear of the surface. In the form of buildingbricks it is likewise in considerable use; and the builders in some of the principal cities of the United States testify to the perfect adaptation of Buc'n bricks, and to their great superiority and economy over the common clay-brick. It is not easy to limit the application of this valuable rubbish. Wherever durability is required, united with peculiarity of form, there tbe prepared slag will he found perfectly adapted ; for, inasmuch as it can be cast into moulds of any chape, all labour spent in hewing and cutting marble or stone is avoided. It is perfectly compact and impervious and therefore admirably suited for the construction of aqueducts of any size. It remains unacted on by chemicals of the greatest strength, consequently may be employed for making gas-piping, as it will last ont many of the ordinary iron pipe*. When wrought in its higher character, run into suitable moulds, and polished more brilliantly than marble or porphyry, it will furnish pillars, fasadep* slabs, Sic, for the ornamentation of mansions, halls, and public buildings, at a price and in a style not hitherto attained. We have specimens of this beautifully polished material before us, and certainly we can nee in it that which is likely to bring about a complete revolution in house architecture. Who will be content with porous Iricke, perishable stucco-work, or soft, crumbling stone, when such adamantine, cornelian- like material i« to be had, that chall defy the action of London smoke, and factory vapours ? We can picture in our mind's eye a new Belgravia, a second Tyburnia, rising up Bt the bidding of some adventurous Cnbitt or Peto, built with slag-bricks and faced with a polished front of surpassing brilliancy, in the most exquisite forms, and apparently composed of marble, agate, cornelian, porphyry, and malachite. If a shade of dust or smoke settle on it, the first shower of rain restores it to its original brilliancy. Time will have little if any effect on it; and as for repairs or beautifying every third or fourth year, such care would never be needed. All this we expect to see before many seasons shall have paesed over us. It is impossible to over-estimate the advantages likely to arise from this new branch of industry, so simple in its application, yet so widely available in most European countries, not only wiih the refuseproducts of iron works, but wi:h those resulting from the smelting of copper, lead, and zinc ores. The rough slabs or tiles for pavements or roofing can be sold with a large profit at fourpence halfpenny the foot. When highly polished, at eighteen pence. In its more finished and ornamented forms for architectural purposes, this material possess* of course a much greater value, dependent on its durability and beauty, Regarding this important discovery from whatsoever point of view, whethf r in reference to the vast quantity of now useless refuse that may bs made valuable, to the many interests that will be benefited by it — iron-masters, copper smelters, builders, architects, bouse- decorators, and watercompanies—we cannot but look upon it as one of tbe most promising results of modern science in an age peculiarly fruitful in marvellous inventions, and rich in its daily Penny Wisdom.

We. have in a previous paper shown the marvellous powers of electricity in the production of light. Here we findjthe same subtle element busily employed in making mere rubbish a beauti* ful and useful adjunct to the arts. How far tha same agpney may be made subservient to the improving of our smelted metals and other products of the furnace, we dare not venture to predict. We will content ourselves with directing the attention of founders, assayers, and all workers in metal, glass, and porcelain to the subject.

A Yankee is making his fortune in the valley of the Mississippi by selling pmely vegetable pills (pea?e soaked in a solution of liquorice) for the cure of all disease?.

"I believe the jury have been innoculated with stupidity," said a lawyer. "That maybe," said his opponent, " but the bar are of opinion that you have it in the natural way."

Cloudless hides for weeks together are wearisome enough, and the trite exclamation of the late Captain Foihergill may be in point. This eccentric officer was returning from India, where he bad served for years ; coming on deck, when entering the English Channel on a foggy November morning, "Ha!" said he, to the lieutenant of the watch, " this is what I call something like— none of your cursed eternal blue skies here! A fellow can see his own breath now 1"

Benefit derived from Advertising. — E. D. W. Clifford, a young gentleman living at Leavenworth, Indiana, recently advertised in the Louisville Democrat for a wife. He writeß to the editor that he is thoroughly convinced of the advances of advertising. He says he has received, in answer to the advertisement, ?94 letters, 13 daguerreotpye likenesses of ladies, two gold finger ring*, 17 locks of hsir, one copy of Ike MartelPi " Reveries of a Bachelor," one thimble, and two d<zen shirt button*. He cught to be ton* vinced. Sarcasm and Scandal.— Sarcasm js miv to be the lanaunge of the devil. Perhaps no. But what is scandal? Sarcasm is the language the devil u«PB to your face; ccamial, that which he uses hehind your DBek. A woman has t cued for a divorce in Indiana (U.S.) on the ground that her husband's feet were so cold thnt it distressed her. A ca«e of clear incompatibility of temperament and Bole,