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of five miles an hour, was very great, and caused uncomfortable vibration in the houses along main thoroughfares; on the other hand, light traction engines were being successfully used, drawing from four to five tons of market produce through the streets of London without causing undue vibration, and at a cost said to be about one-half that of horse traction. A far more burning question was that of the speed of motor-cars along our public thoroughfares. The struggle to maintain a trophy at home, or to regain it from abroad, was one in which every inhabitant of this country sympathised. The great Gordon-Bennett Cup race in July last was decidedly international in character-French, Germans, Americans, and English contesting for the prize. M. Jenatzy covered a distance of 327 miles in six hours 39 minutes, or at the rate of 494 miles an hour, though he attained to a speed of 61 miles an hour between the points of control. Even this speed was exceeded at a trial in Phoenix-park, Dublin, when Baron de Forest attained to a rate of 86 miles an hour. But between racing speed and ordinary travelling speed there is necessarily a great difference, and our 20 miles maximum on country roads is in excess of that allowed in France, where it is now fixed, though the author believed not enforced in the open country, at 18 miles, and at 12 miles where there was much traffic. The use of motor-driven vehicles for road traffic was so intimately associated with improvements in prime movers that it would interest the members of the section to be reminded of

the opinion expressed more than 20 years ago by Sir Frederick Bramwell, who presided over the meeting of the British Association, at Bath, in 1888. In a paper read at the Jubilee meeting of the Association, at York in 1881, Sir Frederick Bramwell

said:"However much the Mechanical Section of the British Association may to-day contemplate with regret even the mere distant prospect of the steamengine becoming a thing of the past, I very much doubt whether those who meet here fifty years hence will then speak of that motor except in the character of a curiosity to be found in a museum." To keep alive the interest of the Association in this subject, Sir Frederick Bramwell had kindly offered, and the council had accepted, the sum of £50 for investment in 2 per cent. self-accumulative Consols, the resulting sum to be paid as an honorarium to a gentleman to be selected by the council to prepare a paper having Sir Frederick's utterances in 1881 as a sort of text, and dealing with the whole question of the prime movers of 1931, and especially with the then relation between steam-engines and internal-combustion engines. That paper would doubtless prove to be a very valuable contribution to the proceedings of the Association, and one could only regret that many of those assembled here to-day could not hope to be present when it was read, and to listen to an account of the nearest approach which had then been made towards the production of a perfect [r'me mover.

THE ORIGIN OF JEWELLERY.* Personal ornaments in civilised countries consist o precious metals, stones, or imitations of stones, pearls (which are the product of shells), or shells themselves, amber, jet, and occasionally various other objects, such as tiger's claws, &c. It has hitherto been held that men and women were led by purely æsthetic considerations to adorn themselves with such objects; but a little research into the history of such ornaments leads to a very different conclusion. The fact is that mankind was led to wear such objects by magic rather than by aesthetic considerations. The jewellery of primitive peoples consists of small stones with natural perforations, e.g., silicified spones or joints of coniferæ, or of substances easily perforated, such as amber, the seeds of plants, shells, the teeth and claws of animals, bones, or pieces of bone, pieces of wood of popular kinds. Later on they learn to bore hard stones, such as rock crystal, hematite, agate, garnet, &c., and to obtain the metals.

All peoples value for magical purposes small stones of peculiar form or colour long before they can wear them as ornaments; e g., Australians and tribes of New Guinea use crystals for rain-making, although they cannot bore them, and crystal is a powerful amulet in Uganda fastened into leather. Sorcerers in Africa carry a small bag of pebbles as an important part of their equipment. So was it in Greece. The crystal was used to light sacrificial fire, and was so employed in the Church down to the fifteenth century. The Egyptians under the twelfth dynasty used it largely, piercing it along its axes after rubbing off the pyramidal points of the crystal, sometimes leaving the natural six sides, or else grinding it into a complete cylinder. From this bead came the artificial cylindrical beads made later by the Egyptians, from which modern cylindrical glass beads are descended.

The beryl, a natural hexagonal prism, lent itself still more readily to the same form, e.g., the cylindrical beryl beads found in Rhodian tombs. The Babylonian cylinders found without any engraving on them on the wrists of the dead in early Babylonian graves had a similar origin. It has been universally held that Babylonian cylinders, Egyptian scarabs, and Nycenean gems were primarily signets; but as the cylinders are found unengraved, and as many as 500 scarabs are found on one mummy, and as Mycenean stones are often found without any engraving, it is clear that the primary use was not for signets but for amulets. The Orphic Lithica gives a clear account of the special virtue of each stone, and it is plain that they acted chiefly by sympathetic magic; e.g. green jasper and tree agates make the vegetation grow, &c. The Greeks and Asiatics used stones primarily as amulets, e.g. Mithridates had a whole cabinet of gems as antidotes to poison. To enhance the natural power of the stone a device was cut on it, e.g. the Abraxas

Abstract of a paper read by Professor W. Ridgeway, before the Anthropological Section of the British Association, at Southport.

cut on a green jasper, the special amulet of the Gnostics. The use of the stone for sealing was simply secondary, and may have arisen first for sacred purposes. Shells are worn as amulets by modern savages, e.g. cowries in Africa, where these or some other kind of shells were worn in Strabo's time to keep off the evil eye.

Red coral was a potent amulet worn by travellers by sea, as at the present day in Mediterranean lands, and if pounded up it kept red rust from corn. Pearls

are a potent medicine in modern China. Seeds of plants are medicine everywhere; for example, the ratti (Abrus precatoria) is used in India for rosaries, and also in Africa; the seed of wild banana is especially valued in Uganda, &c. The claws of lions are worn as amulets all through Africa, and are "great medicine," and imitations of them are made. So with teeth of jackals, which are imitated in wood if the real ones are not to be had, and boars' tusks in New Guinea. When gold becomes first known it is regarded exactly like the stones mentioned. Thus the Debæ, an Arab tribe, who did not work gold, but had abundance in their land, used only the nuggets, stringing them for necklaces alternately with perforated stones.† Magnetic fron and hematite were especially prized, the power of attraction in magnetic iron, as in the case of amber, causing a belief that there was a living spirit within. Hence ron in general was regarded with peculiar veneration, and not because it was a newer metal, as is commonly stated.

It is thus clear that the use of all the objects still employed in modern jewellery has primarily arisen from the magical powers attributed to them, by which they were thought to protect the wearer.

AUSTRALIAN SPONGES.

Although the existence of various kinds of sponge on the Australian coast has been known for many years, the possibility of cultivating those descriptions possessing a commercial value has only recently attracted attention. It appears that in August, 1900, the trustees of the Australian Museum, in Sydney, received from the New South Wales Fisheries' Commissioners a donation of a large collection of sponges obtained by their inspectors stationed on the seaboard of the State, the object being to ascertain the number of species suitable for commercial purposes, or that might be rendered such by cultivation. The work of investigation was entrusted to Mr. Thomas Whitelegge, the Museum Zoologist, who devoted considerable time to the work of classifying the collection, consisting of about six hundred and thirty specimens, of which forty belonged to the commercial kinds, seven being regarded as possessing an economic value. The result was to show that at least eight species and varieties of sponge, having a

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commercial value, were indigenous to the New South Wales coast, and that it was probable a systematic investigation would prove the existence of other kinds of equal or superior commercial value Many of the specimens had been washed ashore during heavy gales, while others were waterworn or dried up. Several kinds were obtained from Sydney Harbour. The living sponge has been seldom met with, but during some fierce gales in 1901 the heavy seas cast on the harbour and ocean beaches an enormous amount of marine products. Seaweed was piled up to the depth of three or four feet, and with it a vast quantity of animal life. Several of the heaps, composed of the smaller organisms, were simply large, brilliantly variegated mounds, containing representatives of the New South Wales marine fauna and flora. In addition to the large and varied accumulation of seaweeds, the beaches were strewn with fish, molluscs, crustacea, worms, alcyonareans, echinoderms, zoophytes, ascidians, and sponges, the two latter being the most abundant. The beaches in some places were carpeted with organisms resplendent with all the colours of the rainbow. Here Mr. Whitelegge was enabled to secure numerous living specimens of sponge, and found them beautifully coloured-reddish orange, dark terra cotta, madder brown, dark yellowish stone, orange buff, yellowish cream, and pale cream. The tints changed after death, one kind, a canary colour, becoming bright purple. Among the commercial sponges, a new species, the Euspongia illawarra, is declared to be “quite equal" if not superior to many of the kinds used for domestic purposes. Mr. Whitelegge found the dried skeleton soft and extremely elastic; when wet it was tough, elastic, and apparently very durable. In colour it is a light-yellowish brown. The main fibres are entirely free from foreign bodies such as sand grains and spicule fragments, which are present in nearly all the sponges purchasable in Sydney. In fact, it may be said that all sponges, economic and non-economic, so far examined, have foreign bodies in their compositior, but the Euspongia illawarra is superior to all previously known in this respect. To use Mr. Whitelegge's own words, "This sponge is by far the best occurring on the coast, and is equal if not superior to many of the commercial sponges procurable in Sydney." The discovery that sponges of commercial value are abundant on the New South Wales coast has raised the question of their systematic cultivation, and here it has been ascertained that it can be readily propagated, as on the coast of Florida, by placing small living cuttings in suitable places. The most favourable location seems to be anywhere within the bays and lagoons free from heavy seas, too strong currents, and too much fresh water; and in moderate depths for easy handling and observation. The growth is faster in strong currents, but in such a case the shape is apt to be poor and the quality harsh. Under favourable conditions the cuttings double their size in six months, consequently eighteen months to two years will produce marketable sponges. The growth

is naturally regulated largely by local conditions, such as temperature, food supply, and situation; and Mr. Whitelegge advises that "after fixation the material with the attached sponge could be transported to places calculated to encourage rapid growth." His own experience teaches him "that the finest specimens of sponges ... are generally found suspended under stones or from the roofs of caves. Under such conditions they are shaded from excessive light and possibly have a more abundant food supply, or the inverted position gives the sponge a better chance of obtaining food."

SPANISH OLIVE OIL.

During recent years efforts have been made to improve the quality of the olive oil produced in Spain, so as to enable it to compete in foreign markets with the French and Italian oils, which are so universally appreciated. Some measure of success has already attended these efforts, and this has encouraged the leading Spanish oil crushers to spend money on improvements in their machinery with, it is said, every prospect of a good return. In Barcelona, the pickling of green olives is an important branch of industry; besides the home consumption, which is large, about 7,000 tons are, according to Consul Lay, annually exported. The olives are packed either in bottles or kegs. For pickling, the olives are carefully selected; all those that are in the slightest degree bruised or damaged are rejected, as only the perfect fruit is capable of being preserved. The selected olives are then placed in fresh water to soak for a few days, care being taken to change the water frequently; they are then put into the pickling mixture, which is a solution of common salt and soda, the olives being entirely covered. This is the general method. adopted, and though some may slightly alter the solution used, and add to it certain aromatic substances to flavour the olives, the basis of the preparation is invariably common salt and soda. Ripe and half-ripe olives are preserved only in small quantities, as there is little demand for them. Until quite recently little attention was paid to the method of extracting oil in Spain, and consequently in many parts the most primitive methods are still in use. It is usual for the small grower himself to extract the oil from the olives grown on his land; and as he frequently does not own the necessary appliances, he borrows them from the nearest town, paying for their use either in money or oil. These machines are of the most primitive description. The olives are first crushed in a mill turned by a horse or a bullock. They are then placed in lever presses and the oil thus extracted, boiling water being generally used in the process. These wooden presses, though powerful, are very slow, and it often happens that the olives have to be stored until the presses are available, with the result that fermentation sets in, and this naturally

detracts from the quality of the oil. It is said that there are between 3,000 and 4,000 of these presses in Spain. Formerly the pulp remaining in the presses was used' as fodder or fuel, but now it is sold, and a second extraction of oil is made from it. There are sixty-three mills in Spain for extracting oil from this pulp. The largest oil manufacturers, especially those in the province of Catalonia, have been the first to recognise the importance of improving their machinery; the old crushing mills and wooden presses have been replaced by steel cylinders and hydraulic presses, so that not only is a greater yield obtained, but the quality of the oil is better. Nearly all the machinery in use is of Spanish make. After being extracted, the oil is run into earthenware jars or tin tanks, and after a certain time, strained. It is then poured out into receptacles to be kept until required, alcohol being sometimes used to keep off the action of the air. The lower grades of oil are used in the manufacture of common soap.

General Notes.

ALUMINIUM AS AN ELECTRICAL CONDUCTOR.In a paper read before the Engineering Section of the British Association, Mr. J. B. C. Kershaw gave the results of tests of the suitability of aluminium as an electrical conductor for bare overhead transmission lines, as a substitute for copper. These tests were made in order to ascertain the resistance to corrosion offered by commercial aluminium rod and wire under the conditions obtaining with exposed bare overhead wires. Samples of aluminium rod and wire were ob tained from the principal English firms, and in order to make the series of observations more complete. samples of galvanised iron wire, and of copper and tinned copper wire, were also submitted to atmospheric exposure in two localities in Lancashire. The tests extended from October, 1899, to December, 1902. All the samples of aluminium gained in weight during exposure, and all were pitted and corroded, especially on the under side where the water drops had collected and dried. The rods appeared to have suffered rather less than the wires, and it is therefore probable that in the course of drawing down, aluminium wire undergoes physical change. The author concludes that some of the aluminium rod and wire which was being manufactured and sold in England for electrical purposes in the years 1899 and 1901, was not able to stand atmospheric exposure on the coast of Lancashire without corrosion, and argues that it is only a fair deduction from these exposure tests to assert that aluminium manufacturers have yet to prove the metal a satisfactory and durable substitute for copper in bare overhead transmission lines, or for electrical work which involves exposure to climates near the sea

coast.

Journal of the Society of Arts, No. 2,654. VOL. LI.

FRIDAY, OCTOBER 2, 1903.

All communications for the Society should be addressed to the Secretary, John-street, Adelphi, London, W.C.

The demonstration in the Empress Theatre will commence at 8.30 p.m. sharp.

The number of the party will be limited to 200. Not more than two tickets can be issued to any one member. They will be issued in order of priority of application. Members. desiring to avail themselves of the invitation should apply at once to the Secretary of the Society, stating whether one or two ticketswill be required.

In all cases admission to the theatre will be provided as well as admission to the Exhibition.

Notices.

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The Committee of this Exhibition have invited a party of the members of the Society of Arts to visit the Exhibition at Earl's Court on Wednesday, October 14th (afternoon and evening), and inspect the exhibits, including those to which the Society of Arts medals will have been awarded.

The members accepting the invitation will also have an opportunity of seeing the historical pageant and modern fire service display known as "Fighting the Flames."

The members will assemble at 4 p.m. inside the Warwick-road entrance of the Earl's Court Exhibition.

A round of the exhibits will be made in three parties, and the exhibitors will be requested to be in attendance at their exhibits to explain or demonstrate their appliances or work.

Modern fire appliances will be demonstrated at the lake from 5 to 6 p.m. (long ladders from 5 to 5.30 p.m. and fire engines from 5.30 to 6 p.m.).

The three parties will start to view the exhibits respectively as follows:

Party "A."-Ducal Hall, 4.5 p.m., going by way of Queen's Palace, to Imperial Court.

Party "B" will start viewing in Imperial Court, at 4.10, visiting the Lake, Queen's Palace, and end at Ducal Hall.

Party "C" will commence in the Queen's Palace, 4.10 p.m., visiting the Lake, Ducal Hall, and ending at the Imperial Court.

The London Salvage Corps, by kind permission of Lieut.-Col. Fox, will turn out and drill in the Western Gardens at 6.30 and at 7.30 p.m.

PRIZE FOR A DUST - ARRESTING RESPIRATOR.

The Council of the Society of Arts are prepared to award, under the terms of the Benjamin Shaw Trust, a Prize of a Gold Medal, or Twenty Pounds, for the best DustArresting Respirator for use in dusty processes, and in dangerous trades.

The apparatus will be required to fulfil the following conditions:

(1.) It must be light and simple in construction.

(2.) It should be inexpensive, so as to

admit of frequent renewal of the filtering medium or of the Respirator as a whole; or alternatively it should be of such construction that it can be readily cleaned.

(3.) It should allow no air to enter by the nostrils or mouth except through the

filtering medium.

(4.) It should not permit expired air to be rebreathed.

(5.) The filtering medium, though it should be effective in arresting dust particles, should not offer such resistance as to impede respiration when worn for some hours under the actual conditions of work.

(6.) It is desirable that it should be as little unsightly as possible.

It should be noted that the prize is offered for a Respirator intended merely to arrest dust, and not for a chemical Respirator designed to arrest poisonous fumes. The applications. of such chemical Respirators are more limited,. and there are special requirements connected with them. The Council have, therefore, preferred to limit the range of their present offer to the simpler and more important cases of

dust, either dust of all kinds or of some special character, e.g., iron or steel.

Inventors intending to compete should send in specimens of their inventions not later than 31st December, 1903, to the Secretary of the Society of Arts, John-street, Adelphi, London, W.C. Such specimens must be accompanied by full descriptions, and in cases in which the apparatus has been put into actual use, the experience of such use should be given.

The Prize will be awarded on the report of judges appointed by the Council.

The Competition is not limited to British subjects.

The Council reserve to themselves the right of withholding the Prize, of extending the time for sending in, or of awarding a smaller Prize or smaller Prizes.

Further particulars will be found in previous announcements in the Journal. The last of these appeared on 14th August, 1903.

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Proceedings of the Society.

CANTOR LECTURES.

PAPER MANUFACTURE.

BY JULIUS HÜBNER, F.C.S. (Director of the Dyeing, Frinting, and Paper - making Department, at the Municipal School of Technology, Manchester.)

Lecture IV.-Delivered February 23rd, 1903. Fourdrinier paper machine-Single cylinder and other types of paper-making machines-Finishing -Cutting-Paper-testing - Experimental paper

making.

We will now follow the pulp, as it comes from the strainers, on its journey through the Fourdrinier paper machine (Figs. 22 elevation, and 23 plan, pp. 858-860), during which it is rapidly converted into a continuous web of paper.

A small box (d), provided with a stirrer, is generally placed between the strainer and the machine; from this the pulp flows on to the machine over the so-called "apron," a piece of sheet rubber the width of which is regulated according to the width of paper made. Froth is prevented from getting on to the paper and an irregular flow of the pulp, apt to cause unevenness, is avoided, by means of thin strips of brass which run across the full width of the machine, immediately above the wire, and close to the apron.

The length of these strips, which are termed "slices," as well as their distance from the wire, are adjusted according to requirements. From the "apron," the pulp travels on to the endless wire on which the paper is actually made and which corresponds to the mould of the hand maker. A number of moulds are thus, practically speaking, placed closely together so as to form one endless mould.

The deckle placed on the hand mould, has also its counterpart in the two square rubber bands (e) which run on either side of the wire and so prevent the pulp from spreading beyond a certain width. The length of the wire naturally varies very considerably with the kind of paper made and also with the speed at which the machine is run. The mesh of the wire varies from 60 to 100 warp wires per inch. The endless wire is supported at the end nearest to the strainer by the "breast roll" (f), whilst it returns at the other end of

⚫ I am indebted to Messrs. Bentley and Jackson, Limited, for the drawings of the Fourdrinier paper machine.

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