FENCING

the period from ro1o to 1926 was 2 very critical one for british fencing. up till 1914 it was increas- ing in popularity and rising in its general standard when, with the outbreak of the world war, its activities came to an abrupt end. when, in 1919, more normal conditions had returned, the outlook was not of the best. the experienced fencers were suf- fering from their long period of inaction and there were no young fencers ready to step into their places; for fencing, above all 22 other sports, demands a long period of apprenticeship. it is a wonderful tribute to the fascination of the art, that in 1925 fencing had become more popular than ever, that its general standard is considerably higher than in the years before the war and that its appeal is far more general. fencing in the services —a marked feature of this improve- ment is to be seen in the royal navy, the army and the royal air force. in the past the leading civilian fencers regarded the fencing of army and navy officers with scant respect, but in the six years from 1920 to 1925 inclusive, 5 out of the 18 amateur championships held with the three weapons, foil, epee and sabre, were gained by officers on the active list of the services. this improved standard is to be noted also at the universities and at the public schools, though naturally not to the same extent. fencing clubs.—the most hopeful development for the future, however, lies in the more general appeal of fencing. in addition to the established salles, the london fencing club with prof. mimiague, the salle bertrand, salle tassart, salle alibert, salle grave, the royal automobile club with prof. volland, other fencing clubs have been recently formed which extend the pleas- ures of fencing to a class which in pre-war days never thought of it. such are the grosvenor club, the lensbury club and the tom hughes club, among others, and the members of these clubs are rapidly attaining a marked proficiency with foil and epee. outside london, in the provinces, at birmingham espe- cially, and in scotland, the popularity of fencing is increasing. two features of present-day fencing are to be regretted. in the first place the introduction of epee methods into foil play has become marked in recent years, and as long as the foil is regarded as a competitive weapon these methods will no doubt continue. in the two competitions for the thompson trophy, between american and british representatives, the former easily defeated the more stylish british foil-fencers by using the weapon as a fighting rather than as a fencing implement, and their vic- tories no doubt had an effect on the younger generation of foil-fencers. the second indictment refers to epee fencing. assaults with that weapon are now decided in international events by two hits out of three instead of by a single hit. there appear to be three good and sufficient arguments against this practice: (a) where the target is the whole body, so great concentration is required that a single hit is quite sufficient to determine the issue: (4) the knowledge that a single hit is not fatal tends to carelessness over the first hit; (c) a fencer who has won the first hit can win the encounter equally with a good second hit or a coup double, and anything which tends to exploit the coup double is much to be deprecated. the olympic games.—in the olympic games of 1912, the british team did not make a great show, but in the international fencing tournament, held at earl’s court, london, comm. e. w. h. brookfield, r.n., tied for first place with the sabre. in 19t4 that fire fencer, r. montgomerie, by his victory in the epee championship, brought up the number of his individual cham- pionship successes to eight, a record for a british fencer. in the olympic games of 1920 capt. r. dalglish, r.n., was placed sixth in the final sabre pool and also awarded a special prize for ‘* good sportsmanship.” anglo-american contests —this olympiad, with its apparently inevitable squabbles and bickerings, resulted in a special rap- prochement between the teams of the united states and great britain and started the compctition between the two nations for the thompson trophy. the first meeting was held in america during nov. 1921, and resulted in a victory for the united states by 25 points to 21, but great britain turned the tables in the summer of 1923. in 1923 e. seligman won the sabre champion- ship, a feat which he repeated in 1924, and so became the first british fencer to gain a championship with all three weapons, and he further distinguished himself by reaching the final pool of the foil championship in the olympic games of 1924 in paris, when he had to retire owing to a strain, after beating the winner. he also qualified for the second round of the sabre championship and capt. r. dalglish, r.n., also did well; while c. h. biscoe feng yu-hsiang—ferdinand reached the semi-final pool of the epee championship. in these same olympic events, the united states were well represented by bloomer, boyce, calnan, jeter, breed, milner, gignoux, macpherson, lyon and costner. in 1923 two grands assauts d’armes were held at the hotel cecil and the grocers’ hall, london, and one in 1924 at the royal automobile club, london. in these many of the most distinguished continental fencers took part, both amateur and professional, including a. massard, m.c., l. gaudin, r. l. heide, c. lafontan, a. pope, aldo nadi, e. tack, f. de smedt, j. rossignol and many others. fencing among women has devel- oped extraordinary popularity. jn 1925 the three ontstanding women fencers in great britain were miss gladys davis, miss gladys daniell and mrs. freeman. winners of the amateur championships # foil epte sabre 1910 r. montgomerie e. m. amphlett | a. ridley-martin 1911 e. m. amphlett j. p. blake w. hammond 1912 p. g. doyne r. montgomerie | capt. c. ne van- der by 1913 g. oe pio g. g. m. vereker | a. ridley-martin 1914 r willoughby r. montgomerie | w. hammond 1920 p. g. doyne m. d. v. holt lieut. c. a. | , kershaw, r.n. 1921 r. sutton capt. hfs. huntington w. hammond 1922 r. sutton g. m. burt a. hh. corble 1923 maj. stenson | : cooke m. d. v. holt e. seligman 1924 flight-lieut. f. g. sheriff c. h. biscoe e. seligman 1925 flight-lieut. f. g. | maj. c. b. notley | lieut.-comm. sheriff c.a, kershaw, rn. brptiograpuy.—e. castle, schools and masters of fence (1884); l. rondelle, foil and sabre (1892); c. a. thimm, 4a complete bibliog- raphy of fencing and duelling (1896); c. de bazancourt, secrets of the sword (1908); h. a.c. dunn, fencing (1924). (t. co.) feng yu-hsiang, chinese soldier, and the so-called ‘ chris- tian general” first came into prominence when, on aug. 25 1921, he was appointed tuchun, or military governor, of shansi. in 1922 he was transferred to peking and played a decisive part in the chihli-fengtien war of that year. during 1923 his troops were stationed at nan-yiian, near peking, and it was inevitable, in view of the doubtful authority of the president and his min- istry, that he should play an important part in the political in- trigues of the capital. these manoeuvres culminated in his resig- nation, the flight of president li and the coup d’etut which re- sulted in the assumption of office by tsao-kun. feng retired to the northwest frontier, where he became director of defence, but returned to aid chang-tso-lin against wu pei-fu in 1924. after wu’s defeat, feng turned against his ally and seized pe- king, thus forcing chang to retreat to mukden. he dominated the capita) throughout 1925 and at the end of the year captured tientsin. chang’s victory at mukden, however, led to feng’s retirement to mongolia. feng earned his sobriquet by embracing christianity after witnessing, it is said, the heroism displayed by missionaries during the boxer outrages. ferdinand (1861-— _—s+dy«y ex-kngofbulgaria (see 10.269).— king ferdinand in 1911 was the instigator of the balkan league between bulgaria, serbia, greece and montenegro, which was formed in 1912 and enabled these four states to declare war against turkey that same year. this pact provided for the future division of the balkan peninsula, reserving to the arbitra- tion of the emperor of russia the solution of any doubtful claims. the war started in oct. 1912, before the conclusion of the treaty of ouchy, which put an end to the italo-turkish war (oct. 15). under the command of king ferdinand, the bulgarian army dealt the most rapid and decisive blows to the enemy; victorious on the battlefields of kirk kilisse and lule burgas, and having conquered most of macedonia and thrace, it started on the open road to constantinople. europe grew alarmed: the great powers brought about the armistice of dec. ferdinand i—ferro-concrete engineering 3 1912, and the london conference, which started on dec. 13. these discussions, however, ceased abruptly, and military operations were resumed on feb. 3 1913. the bulgarian armies attacked at gallipoli and chatalja, and after a gallant siege entered adrianople on march 26 1913. however, the treaty of london which followed did not sanction these victories, and its decisions instead of inaugurating peace, provoked a war between the balkan states, which began on june 30 1913, by a simulta- neous attack of the serbs and bulgarians. the former allies be- came bitter rivals, rumania and turkey joining montenegro, greece and serbia against bulgaria, who, finding herself closed in by four enemies at once, was forced, after a few weeks of brave but useless resistance, to submit unconditionally to the victors’ terms. the treaty of bucharest, signed on aug. 10 1913, annihilated in one stroke the brilliant results obtained through the heroism of the bulgarian armies in 1912-3. it deprived bul- garia of all her conquests including the town of silistra and part of the dobruja and gave to the serbians and greeks the province of macedonia for which bulgaria had made all the sacrifices of the first balkan war. this treaty was the principal cause of bulgaria’s participation in the world war on the side of ger- many. it explains the resentment of king ferdinand and his govt. against the other balkan states. had the allied powers in 1914 guaranteed the revision of the treaty of bucharest, bulgaria would have co-operated with them; but as they failed to do so, germany was able, by illusory promises, to induce bulgaria, who felt she had been unjustly treated, to fight for the german cause. these german manoeuvres did not succeed at once, for king ferdinand began by proclaiming the neutrality of bulgaria in nov. 1914. during may 1015 the bulgarian govt. sounded the four great powers, with regard to the fulfilment of bulgaria’s legiti- mate claims in macedonia. as no concrete answer was re- turned, king ferdinand turned to germany, where his applica- tion was received with great cordiality. berlin made lavish promises at once. german envoys hurried to bulgaria, with a view to persuading the king and the govt. to conclude a mili- tary alliance with germany. the desire for revenge against serbia, greece and rumania inspired ferdinand to bind bulgaria to the central powers. on sept. 21 1915 he gave the order for general mobilisation, though his govt. advised armed neutrality. in view of this equivocal situation russia sent an ultimatum to bulgaria on oct. 4 1915, which was succeeded by formal declara- tions of war against bulgaria on the part of serbia, france, great britain and italy. bulgaria was definitely in the german camp: under gen. gekoff, commander-in-chief, her armies were victorious on most of the battlefields of macedonia, thrace and rumania, in 1915, 1916 and 1917, against the serbs, and against the rumanians. the kaiser, the king of saxony and the king of wiirtemberg all paid official visits to king ferdinand at sofia. however, in sept. 1918, the bulgarian army, discouraged by innumerable hardships, was defeated at dobropole, mace- donia, by the allied troops. this was the sign for a general retreat. an armistice was signed at salonika on sept. 30 which ended the war between bulgaria and the allies. after this catastrophe king ferdinand abdicated in favour of his son boris on oct. 4 1918 and left sofia the same evening for coburg where he has lived since in retirement. (a. sr.) ferdinand i. (1865- ), king of rumania, was born aug. 24 1865 at sigmaringen, prussia, the second son of prince leopold of hohenzollern-sigmaringen. as king charles had no son it was decided that the succession should be continued in the family of prince leopold, and prince ferdinand, charles’s nephew, became crown prince of rumania and hcir presumptive to the rumanian throne in march 1889. prince ferdinand took a great interest in military questions and the organisation of the rumanian army on modern lines was in no small measure due to his energy and enlightened advice. he was commander-in-chief of the rumanian armies during the bulgarian campaign of 1913. on jan. 10 1893 he married princess marie, eldest daughter of the duke of edinburgh, duke of saxe-coburg-gotha. six children were born of the marriage. 23 when ferdinand ascended the throne on oct. 11 1914, ru- mania was passing through one of the most critical periods of her history. at the crown council held under king charles at sinaia soon after the outbreak of the world war, the members of the cabinet who were in favour of intervention on the side of the central powers were greatly outnumbered and in spite of charles’s support of the minority, it was almost unanimously decided that rumania should remain neutral. later king fer- dinand, who had in the meantime succeeded to the throne, found himself in an extraordinarily painful situation when he realised that an armed intervention in the cause of rumania’s national unity was unavoidable. he, however, conquered his feelings as a german and a hohenzollern, and when the moment came, he did not hesitate to declare war on his native country. as a con- sequence he was disowned by the hohenzollern family. when bucharest was occupied by general mackensen, king ferdinand and the royal family withdrew with the govern- ment and the army into moldavia. there he endured with the rest of the population a most appalling period of anxiety, sick- ness and want. the bolshevist revolution and the collapse of the russian armies came as a crowning misery. fortunately however, the rumanian army, headed by king ferdinand, re- pulsed the german attack at mardsesti, thus saving the rest of the country from invasion. in 1918 the provinces of bessarabia, bucowina, transylvania and the banat had become united with rumania, and on oct. 15 1922 king ferdinand was crowned at alba julia king of all rumanians. two most important reforms, the agrarian reform and the inauguration of universal suffrage, were enacted under ferdi- nand’s reign. the expropriation of large estates and their con- version into small holdings did much to guarantee the peaceful development of an agricultural country such as rumania. king ferdinand was the first landlord to hand over his estates to his peasant-soldiers. it was also due to his initiative that the thorny jewish question was solved by the grant of full civil and military rights to the rumanian-born jews. in dec. 1925 ferdinand’s eldest son, charles, renounced his claims to the throne, and charles’s son, michael, became heir apparent. (g. bo.) ferrero, guglielmo (1871- ), italian journalist and author, was born at portici, near naples, july 31 1871. at an early age he joined the stafi of the radical semi-republican secolo of milan. he travelled abroad considerably, and made a certain reputation by his books l’uropa giovane (1897) and i] militarismo (1898); engl. tr., 1902. later hestudied roman his- tory, and in 1902 published his grandezza e decadenza di roma, which established his fame as historian among the general public rather than among scholars. he, in fact, applied the methods of journalism to history. in politics a radical democrat, on the outbreak of the world war he was an ardent supporter of the allied cause, which he identified with that of democracy, and advocated italian intervention. after the war he published numerous articles and several books in italy and abroad, inspired by the most gloomy forebodings of imminent catastrophe for italy, europe and the world’s civilisation. among these later works is da fiume a roma (milan, 1923), also published in english under the title four years of fascism (1924). ferrier, paul (1843-1920), french dramatist (see 10.288), died at nouan-le-fuzelier sept. 11 1920. ferro-concrete engineering (see also bripces; dams; factory; roap construction).—owing to a combination of circumstances, technical, economic and manufacturing, great developments in reinforced concrete have taken place since 1910, and as a structural system it is now widely appreciated for many purposes on account of its adaptability, lightness and economy of first cost and maintenance. the scarcity of steel during the world war caused reinforced concrete to be used for many structural purposes for which steel had hitherto been considered the most suitable material. another factor in the development has been the progressive improvement in the strength and relia- bility of portland cement as evidenced by the latest revision of the british standard specification for portland cement, 1925, which calls for a neat cement tensile strength at 7 days of 600 24 lb. per sq. in. as compared with 450 lb. for the previous specifica- tion, 1912. | rapid progress has also been made with a new type of alu- minous cement (“‘ ciment fondu ”’), originating in france, but now also made elsewhere, which, while setting initially no quicker than portland cement, nevertheless attains or exceeds tn 24 hours the strength of portland cement at seven days, so that con- crete made with such cement can be brought into service, tf need be, in a day or two. it is claimed also that the cement resists the action of sea water, and that owing to the heat eeneratca in set- ting, it can be used in frosty weather. along with the improvements in cements anich progress has been made in the subject of proper grading, proportioning and mixing of aggregates, sands, cement and water in order to attain the densest, strongest and most watertight concrete. it is well recognised now that, with aggregate and sand of a given material, that mixture of graded material (large, medium and fine) which has the smallest proportion of voids, and which consequently weighs most per unit volume, will be capable, when mixed with- out excess of water, of furnishing the strongest concrete. technical studies —on the technical side, much work has been done in the theoretical analysis of the moments and stresses in arches and continuous framed constructions of varied forms, and the results are available for use in the more accurate deter- mination of stresses and sections. considerable study has also been given to the elastic properties of concrete in relation to the secondary stresses arising from temperature variations and shrinkage of the concrete. foundations.—reinforced concrete construction is adapted to varied uses in foundation work. thus, retaining walls of ample strength can be readily constructed in places where there is no room for a gravity wall of mass concrete. heavy columns can be supported on a relatively thin but widespread foundation of re- inforced concrete with great saving in weight, volume and depth of construction, as compared with mass concrete. on weak ground, a complete layer of light reinforced concrete in the shape of a plain or ribbed slab may be provided to distribute the entire load over the whole basement area of a structure in an economi- cal and efficient manner unattainable with other methods of construction. caissons and floating craft.—an important development in subaqueous foundation work, such as dock walls, breakwaters and bridge piers (see port engineering) consists in the use of reinforced concrete caissons of rectangular, cylindrical or other form, which may be constructed in dry dock or on a staging on dry land, then launched or floated out, towed to the site, and deposited in position on a bed prepared by dredging or by divers. such caissons form a permanent part of the construction and are generally used as a working base for further operations of sinking downwards and building upwards, the top being kept al- ways above water. sinking downwards through suitable mate- rials may be effected by grabbing through open wells in the in- terior of the caisson, while for difficult cases the excavation may be carried on by men working under compressed air. large concrete caissons have been applied in the construction of the upper portions of breakwaters as at valparaiso! and elsewhere. in the oswald street bridge at glasgow,’ cylindrical caissons 20 ft. diameter were used for the foundations of the piers. these caissons were constructed on a staging ashore, fitted with a false bottom, lowered into the water, floated out to position, deposited on the prepared bed, and after removal of the temporary bot- tom, sunk to the necessary depth by grabbing and excavation inside, the pier on top of a group of caissons being built up as the sinking proceeded. concrete ships.—the results of the construction of reinforced concrete cargo vessels were satisfactory and indeed surprising as regards watertightness, main longitudinal and transverse strength and lightness of construction. the hull weight in care- ful designs was less than that of a wooden vessel, though some- what greater than that of a steel hull. the principal disadvan- 1 proceedings of the institution of civil engineers, vol. 214. 2 engineering news record, oct. 1925. ferro-concrete engineering tage lay in the relative tenderness of the thin skin construction under the bumping and rubbing to which a vessel is often sub- ject when in port and when touching the ground. the results were instructive as regards the possibilities of carrying out light watertight concrete constructions with rich concrete of small aggregate without the addition of any special waterproofing material and with very fine limits of cover of concrete and spac- ing of bars. in great britain, in addition to numerous barges and steam tugs, a few self-propelled cargo vessels were also con- structed, the principal being the ‘‘ armistice’? of about 1,100 tons dead-weight capacity. l’lat floors ——there has been a continued tendency toward simplification of structure with a view to speeding up and cheap- ening construction, culminating in the extensive use in the united states of the flat slab floor. in this type main and sub- sidiary beams are dispensed with and a floor of constant thick- ness with a flat under surface is supported directly on the col- umns, which have enlarged heads of square or moulded shape. the floor reinforcement consists of several systems of rods mainly radiating from the columns and placed near the upper surface over the columns and near the lower surface in the interior of panels. the design of such floors is based on very approximate theory controlled by the results of stress measurements in tests of actual floors. ‘the method has hitherto found but little application in britain, where much more use had been made of light flat ceil- inged floors having in their lower part rows of hollow tile blocks set so as to leave intermediate spaces for the formation of nar- row reinforced beams, the floor being completed by a continuous concrete layer placed over the tiles and beams. floors of this type are well adapted for filling in the panels between the main floor beams of structural steel-framed buildings, and have the advantages of lightness and good insulating qualities, while a plaster ceiling can be applied to the grooved soffits of the tiles. rich concrete.—greater recognition is now being given to the value of the cement element in concrete as affecting the strength, watertightness and endurance of the material. starting from 1:2:4 mixture, the one most commonly used in reinforced con- struction, which is seldom quite watertight and on that account may in certain circumstances fail to protect the rods sufficiently, it is found that up to a 2:2:4 mixture the addition of cement is accompanied by a roughly proportionate increase in the com- pressive strength as well as by enhanced reliability, watertight- ness and protecting properties, to the extent that porosity in a 2:2:4 mixture is quite exceptional. the richest mixtures are required for sea construction, such as jetties, especially for the parts above low water, also for tanks, conduits and floating craft which have to withstand water pressure, and for piles which have to undergo severe hammering. pressure conduits have been constructed of 20 ft. diameter for 50 ft. head and in smaller sizes for a maximum pressure of 180 ft. head. (see aqueducts.) long span arch construction—wherever abutment and headroom conditions are suitable and the span is not small, arch construction compels consideration, as thereby a single main truss member (the arch) serves to carry the load as compared with two main members and a web system in the case of a beam or truss. further, the arch has the economical advantage that the thrust is principally taken by concrete, which is cheaper for this purpose than steel, and in large arches only a relatively small proportion of reinforcement is required to take care of such tensile stresses as may develop due to live-load variations and the effects of shrinkage, temperature and rib-shortening in the concrete. the arch form, in addition, lends itself to the at- tainment of good appearance. the largest arch bridge completed in 1926 is the 432 it. span road bridge across the seine at st. pierre du vauvray, france. whereas formerly 400 [t. waslooked on as being near the practicable limit for a concrete arch, recent developments have greatly extended the limits and completely worked-out projects are now in existence for more than one bridge with spans of about 600 ft., and spans of well over 1,000 ft. do not appear to be unattainable. * proceeds of inst. of naval architects, 1918. fertilisers—fibres aesthetic appearance.—surfaces of concrete do not lend them- selves very readily to satisfactory architectural treatment, so that in many fine buildings the supporting framework of rein- forced concrete is entirely hidden behind facework of masonry or other material. good effects in buildings can be attained when the visible concrete is well finished and confined to well- proportioned and suitably lined vertical and horizontal bands of the framework, the rest of the elevation being formed of panelling and facework of other materials. in bridges, principal reliance must be placed on satisfactory form and proportions combined with very careful work in constructing and setting the moulds which form the exposed surfaces. parapets and pillars of good finish and appearance may be precast in small pieces in carefully finished moulds, preferably of metal. bibliography.—m. s. ketchum, walls, bins and grain elevators (1907); illustrations of reinforced concrete structures, designed and erected under the direction of brussel and viterbo (1910); c. hl. desch, the chemistry and testing of cement (1911); o. faber and p. c. bowie, reinforced concrete design, vol. i and 2 (1912); g. a. hool, retnforced concrete construction, vol. 1,2 and 3 (1912-6) f. w. taylor, s. e. thompson and e. smulski, treatise on concrete, plain and reinforced (1916); j. meclan, plain and reinforced, con- crete arches (1917); m. t. cantell, retnforced concrete consiruc- tion, part i (1918), part 2 (1921); g. a. hool and n. c. johnson, concrete hugineers’ itandbook (1918); h. adams and e. r. matthews, reinforced concrete construction in theory and practice (1920); j. williamson, calculating diagrams for the design of rein- forced concrete sections (1920). (j. wr.) fertilisers: see agriculture: scientific developments. fez, morocco (see 10.306), has been since ror2 under the french protectorate. the population in 1921 was 70,540, includ- ing 2,218 europeans. the city has still an active native industrial life and prosperous trade, while european industries, such as oil and soap manufacture, have been established. the town is lit by electric light derived from the falls of wadi iez. the municipal services have been reorganised by the french under the native pasha and his council, and an office of native industries has been set up to conserve the ancient handicrafts. the erec- tion of the new european town of fez has been begun near dar debi bagh. fez is connected with rabat and ujda by narrow- gauge lines, and the line to tangier is finished as far as the span- ish frontier. there are some 30 native olive oil factories round the bab-el-ghisa, and the manufacture of silk textiles occupies about 30,000 people. there are good roads to taza, meknes and qnitra. the new port at qnitra is the nearest to fez. fibres (sce 10.309).—no fundamental changes have taken place in the technology of fibres since 1910, although there have been many minor developments, including an increased use of the lesser fibres for industrial purposes. it is rather in the em- ployment of substitutes and in the evolution of processes which have preduced practically new substances such as “ artificial silk ” (g.v.) that the most striking changes have taken place. war substitutes—during the world war period interesting technical experiments were made, particularly in germany and austria, with various substitutes. these were caused by the shortage of cotton and wool, due partly to the blockade and partly to the huge demand for these fibres for military purposes. cotton was required for explosives and wool for uniforms and the like. early in the war, german experts began to examine the possibilities of other fibres, hoping thereby to supplement their inadequate supplies of cotton and wool. from the stand~- point of fibre technology, these experiments are undoubtedly important but so far have not been of much industrial use. experiments were made with nettles and with twisted paper yarns. the substitution of wood cellulose for cotton cellulose proved of the greatest immediate value to germany. to a large extent she was thereby enabled to eke out her supplies of cotton cellulose and produced considerable quantities of nitro-cellulose propellant explosives from wood pulp. the wood cellulose was prepared from the bisulphite pulps of the paper industry by hydrolytic treatments and the result was a cottonisation of the pulp. this material is usually known as ‘ supersulfit ” and has proved of considerable value during the post-war period for the making of paper. (q.v.). 25 paper yarn.—the “ paper yarn ” industry developed under the pressure of the war to an annual output of 200,000 tons. these yarns were used to quite a considerable extent for textiles, even complete suits being made from “ paper cloth,’ but were characterised by the defects of short fibre length and failed to establish themselves as serious competitors with the older fibres such as cotton and wool. netile fibve—valuable experiments were made with nettle fibre, resulting in indications that it is almost a total failure. the common nettle or urticaceae contains a rough fibre, and since the plant belongs to the same order as ramie or rhea fibre, high but illusory hopes were entertained that from it might be ob- tained a fibre of similar or even better quality, which could be used in the textile industry. nettle fibre has great length of bast, and great variability in dimensions and has to be prepared by chemical methods of separation. the crop-weight is low ana it is difficult to cultivate on a commercial basis. while stout plants can be gathered wild, when transferred to cultivated soil and planted in regular rows, they tend to deteriorate and become thin and weak. these difficulties may be surmounted, but so soon as the war ended fibre users quickly returned to the older and more satisfactory raw materials. jute—long before the war it was known among fibre experts that by treating jute with caustic soda a “ woollenising ” effect is produced. the structure of the fibre is altered, has many resemblances to wool, can be “ carded,” and mixes well with wool. this process was revived in germany and austria during the war and mixtures containing as much as 60% of this vege- table fibre were worked up and spun into serviceable yarns. sisal.—in the post-war period, so far as the old series of hard fibres are concerned,’ the most important developments have been in the direction of increasing their output by opening up new areas in which they are being grown on a commercial scale and in developing alternative plants, such as the expansion of the sisal industry in the british colony of kenya. the sisal is an agave which is indigenous in florida, the west indies and yucatan, and from its leaves sisal hemp is produced. the plant has, however, been transported to distant areas, and at kenya it is now one of the chief exports of the country. in 1912 only 2,500 cwt. were exported; in r919 the quantity had risen to 126,937. in 1924 kenya and uganda together exported 218,740 cwt. of sisal fibre and 9,720 cwt. of sisal tow. the demand for sisal is due to the increasing demands for binder twine, needed by the mechanical reapers which are being employed in ever increased quantities by the great grain produc- ing countries such as the united states, canada, the argentine and australia, particularly for those machines which reap and at the same time bind into sheaves. sisal hemp, a substitute for the original hemp, cannabis sativa, is itself threatened by new competitors such as mauritius hemp, manila hemp and new zealand hemp or phormium tenax, which were well known and widely used before the war. bowstring hemp—this plant flourishes in the shade of old rubber and may therefore prove a valuable crop in old rubber clearings. it is propagated by seed, division or leaf cutting, the latter method being the most satisfactory. the distance of planting is two feet apart each way and the average yield is 14 tons per acre. the plant produces a fine, tough, white and elastic fibre, which is extracted from the leaf by methods similar to those employed in the preparation of sisal. it is usually shipped in bales of four to five hundred-weights. although much valuable scientific information has been acquired concerning this plant—_ and it undoubtedly has considerable possibilities—its production is still in the experimental stage. | roselle fibre—this is obtained from an annual shrub whic belongs to the order of the hibiscus. the fibre is obtained from the branches and main stem, but the latter is of inferior quality. the fibre is suitable for making rope and good quality string, and it is claimed that it can be spun like jute but, so far, it is not certain that it can be produced on a commercial scale. the plant grows toa height of 10 or 12 ft. and therefore must not be planted within a radius of 5 ft. of young rubber trees. it is prepared by 26 retting in stagnant or slow moving water for 8 or 9 days, and all the work can be done by native hand labour and requires no elaborate machinery. it must, however, be bale-pressed for export. arghan.—this fibre stands half-way between the hard and soft fibres and appears to have some of the characteristics of each. it was originally discovered by sir henry wickham in south america, but attempts are now being made to develop it on a commercial scale in malaya. it was first considered as a material for twine and cordage but it possesses a tensile strength which gives a breaking strain of 50% above that of the finest italian hemp or even the best flax. moreover, it can be spun to a much finer lea than is required for twine. a firm cloth which bleaches and dyes well has been woven from it. till recently it could only be spun on a flax machine but it now seems possible to use ordinary cotton machinery. it is a lance-leafed plant, similar to a pineapple, and the long leaves contain more than 20% of pure fibre. it is easily split up into long fibres, 7 feet or more in length, which are almost as delicate as silk, specific leaves on each plant produce a softer and finer fibre than the others, and planters are concentrating attention on these. ar- ghan still is more of scientific than of commercial interest but possesses considerable possibilities. kapok.—this soft fibre is obtained from the pods of the kapok or cotton tree, indigenous to malaya, java and the philippines. considerable and increasing quantities are being exported chieily to australia, america and great britain. the chief distributing centre in europe is amsterdam. it is non-absorbent and lighter than water. when stuffed into life-saving apparatus or into cushions, etc., it will sustain a heavy weight in water for many hours. in consequence it has largely replaced cork-lined appli- ances. the fibre is as buoyant as cork and can be compressed en masse. the peculiar property of the fibre is due to its struc- ture. the fibre canal holds a large amount of air, and the smooth contour of the fibre and the resilience of the air-filled tube give a large air volume to the mass, even when compressed. the fibre is short, light and brittle, and despite much experiment so far, attempts to spin it on a large scale have not been successful. it has a fine lustre and great elasticity. flax.—special efforts have been made to develop the produc- tion of flax in various parts of the british empire in order to replace russia who, in pre-war days, produced annually 525,000 tons of flax and exported at least half of it to europe. flax from the new baltic states and from soviet russia has again begun to appear on the markets. the belfast linen industry, in conjunc- tion with the government, have in recent years devoted special attention to increasing the supply of fibre. in particular, efforts are being made to develop flax growing in england. a special committee was set up in oct. 1924 to consider anew the whole matter, and in the journal of the ministry of agriculture (1925, 32, 310) it was stated that the government had adopted the recommendation of this committee and had acquired two fac- tories and constituted a society, not trading for profit. this society is the flax industry development society and its pri- mary object is the supply of seed of good quality. it is believed this society will be able to supply a far better type of seed than that at present obtainable by flax growers and so lead to a great extension of flax growing of the finest quality within the british isles and throughout the empire. (see cellulose.) brbeliography.—e. goulding, cofton and other vegetable fibres (1911, etc.); j. m. matthews, textile fibres (1913); h. r. carter, the flax, hemp and jute vear book and pocket annual (belfast, 1921, etc.); a. s. moore, linen (1922); j.s.m. ward, textile fibres and yarns (1924). see also report of the departmental committee on the irish flax growing industry (dublin, ed. 5502, 1911); bulletzns of the imperial institute. (j. s. m. w.) fiji islands (see 10.335) have an area of 7,425 sq. m. and a population of 139,541 (1911). the dominant feature of fijian history during the years 1915-25 was the celebration at levuka, on oct. 10 1924, of the islands’ jubilee as a crown colony. after so years of british rule the same “ lali” or native drum was beaten at the same hour and place by the old chief who beat it at the cession of 1874, announcing the ceremonies arranged in fiji islands—fildes honour of the occasion. peace was the object of the cession, and the fijian fully appreciates the peace that for nearly 50 years has remained unbroken. a large tabua (whale’s tooth), presented on the occasion of the jubilee, was accepted by king george as a token of the loyalty and affection of his fijian subjects. population.—the census of 1911 shows that the population in that year was 139,541; in 1921 there were 88,464 males and 68,802 females, total, 157,266. of this total, europeans number 2:4%, fijians 53%, indians 38 °%; the rest are mainly half castes, polynesians, rotumans and chinese. constitution and administration.—the present constitution is regulated by letters patent of jan. 31 1914 (amended in july 1916). it provides for an executive council to advise the gover- nor, and a legislative council; the former now consists of four official and two nominated unofficial members, and the latter consists of the governor, not more than 12 nominated, 7 elected and 2 native members. the natives, however, retain a large share of self-government, and in the remote districts, where little commercial development has taken place, there is but slight modification in the old communal methods of native society. younger natives, who through a certain amount of education have come under the influence of a european social system, are disposed to secure release from communal obligations and to support themselves on their own land or become wage-earners for varying periods in industrial centres or on plantations. many are now engaged in the sugar-mills, and a considerable number as clerks, sailors, carpenters, boat builders and domestic serv- ants. the vast majority, however, remain agriculturists living in native villages and cultivating their tribal lands. educational administration was completely changed in 1916, when a board of education replaced the school boards, an education department was formed and ordinances passed to allow grants to be made to primary and vernacular schools. european education in the colony has made considerable progress, in spite of the fact that the problem is rendered more complex by the numerous races now domiciled in the islands. facilities for primary education are good, and those for vocational training constantly improving. land tenure.—the sale of native lands, except to the govern- ment for specific purposes, was prohibited by an ordinance of i9g12. the standard tenure is leasehold up to 99 years, with security to the tenant for permanent and unexhausted improvements. a native lands commission, comprising a european officer and three native chiefs, has been established to survey and register all native lands. trade and industry.—the total trade in 1924 was £2,565,528, as against {1,999,004 for 1912, {2,329,908 for 1913 and £2,301,139 for 1914—a steady increase which has since been well maintained. there is a preferential tariff in favour of the products and manu- factures of the british empire; and of the total trade of the colony over 60°% is with british possessions, and about 11% with the united kingdom, the balance, about 25 %, being with europe and the united states of america. the main agricultural industries have for long been the production of sugar, copra and bananas. the sugar industry has been hampered by inadequate labour and by a great increase in the world’s production; copra has suffered from a restricted market, the banana industry from plant disease and a protective customs tariff in australia. hence the government continues to make efforts to develop the new rice industry, which is important to the colony with its ise east indian population. the cultivation of cotton, which had ceased in i900, was resumed in 1922 and is almost entirely in the hands of east indians. other developing industries are dairying, sawmilling and the growing and canning of pineapples. communications.—there is regular monthly communication to and from sydney via auckland or directly, and also to and from vancouver via honolulu. the colonial sugar refining company has a narrow gauge railway extending from tavua to na singatoka, a distance of 120 m. over which passengers are carried on specified days. the first section of the main trunk road, which ends at sawani, was completed and opened to traffic in 1924, and, though the total length i metalled roads is jess than 100 m., there is a good length of gravelled roads and of communally-maintained bridle tracks. finance.—the revenue for 1924 amounted to £484,834 as against £283,947 in 1912. notwithstanding fluctuations the revenue has been steadily expanding for years, and though expenditure in the last 10 years has frequently exceeded it, there was a surplus of £50,316 in 1923 and of £33,764 in 1924. (a. r.*) fildes, sir luke (1844- ), british painter (see 8.339), was born at liverpool and educated privately at chester. he studied at the art schools of warrington, south kensington and filing systems—filter-passing microbes the royal academy, and exhibited his first academy painting in 1872. introduced to dickens by millais, fildes was illustrating edwin drood at the time of the novelist’s death. ‘‘ the casuals ” (1874) showed him as a genre painter of power, and a series of venetian pictures were very popular. he was made a.r.a. in 1879, and r.a. in 1887. “ the village wedding ” (1883) and, more especially, ‘‘ the doctor” (1892) is probably the most widely famous of his works. in later years he painted many portraits, among them state portraits of edward vii. (1902), queen alexandra (1905), and george v. (1912). knighted in 1906, sir luke fildes became k.c.v.o. in 1918. filing systems: see office appliances. film: see motion pictures; photograpiiy. filon, pierre marie augustin (1841-1916), french man of letters (see 10.345), died at croydon, england, may 13 1916. in roto he published a short biography, marie stuart, and in tort ll’ angleterre d’edouard vii., and a dramatic poem, shakespeare amoureux. his souvenirs et documents, relating to his former pupil, the prince imperial, appeared in 1912. filter-passing microbes.—these organisms are those which are small enough to pass through a “ bacterial ”’ filter. bacterial filters are made of unglazed porcelain or compressed infusorial earth. the grains of the china clay or infusorial earth used for their manufacture are sufficiently small and uniform to leave insterstices, the cross section of which is 0-2 to o-8 yp in diameter. if a liquid containing microbes whose smallest diam- eter exceeds 0.2 yw be pressed through the filter, the microbes re- main impacted in the smaller crevices. as 0-2 yp is also the limit of size of a particle which can be resolved by the best microscopes (see microscopy) when white light is used, filter-passing organ- isms are either invisible or on the margin of visibility. hence, most of them have been classed as “‘ ultravisible viruses.” discovery.—the first discovery, that an ultramicroscopic or filterable virus was the cause of an animal disease, was made by loefiler in 1898 in the course of some experiments upon foot- and-mouth disease, in which a filter of infusorial earth was used to remove ordinary recognisable bacteria from the diluted con- tents of the superficial vesicles which are characteristic of this disease. the filtrate was free from any particles visible by the microscope and no bacteria developed in it on cultivation. nev- ertheless, injection of this filtrate into animals caused disease. material removed from the vesicles of the animal so infected and filtered again reproduced the disease in a fresh animal. similar experiments were carried out through a number of gen- erations of animals, so that there was no doubt that a virus capable of propagation in the animal body was contained in the filtrates. in the next few years the filterability of the virus was established in the case of infectious pleuro-pneumonia of cattle, south african horse-sickness and fowl plague. yellow fever.—the cause of yellow fever has been shown by noguchi to be a spirochaete which, owing to its thinness and motility, can pass through a bacterial filter. human diseases.—up to 1925 the virus of about 40 diseases of man and domestic animals had been found to pass through a bacterial filter by some reliable observer. the more important of these are the following: foot-and-mouth disease, contagious bovine pleuro-pneumonia, african horse-sickness, fowl plague, yellow fever, cattle plague, sheep-pox, epithelioma contagiosum of birds, swine fever, rabies, cow-pox (vaccinia), molluscum contagiosum of man, equine infectious pernicious anaemia, canine distemper, ‘‘ blue tongue ’’ of sheep, dengue fever, papataci or sand-fly fever, smallpox, trachoma, poliomyelitis, measles, typhus fever, trench fever, mumps, rocky mountain spotted fever and herpes labialis. influenza.—recently, olitzky has succeeded in propagating on special culture media seven varieties of small microbes from the filtrates through a “‘ bacteria proof ” filter of washings of the throats of individuals suffering from catarrhal diseases. one of them is credited, on substantial grounds, with being the cause of pandemic influenza (q.v.), another is supposed by its dis- coverer to be responsible for our common colds. the others do not appear to be of pathological significance. 27 cancer research.—there is now reason to suppose that filter- able viruses play some part in the origin of cancer (g.v.). whena fragment of a malignant tumour is implanted in the tissues of an animal of the same species it generally grows and ultimately kills the animal. the animal cells of which the cancer is composed are endowed with a faculty for growth, uncontrolled by those factors which determine normal tissue equilibrium. the possi- bility that this property was due to infection of the cells by a microbe has, in the past, occupied the attention of investigators, but no experimental basis for this view was afforded till 1911, when peyton rous described a sarcoma of the fowl which differed from mammalian tumours in that it was transmissible from chicken to chicken by means of a filtrate from a filter which kept back all of the malignant cells (much too large to traverse its pores) and also any bacteria of ordinary dimensions. this filtrate could be dried at a low temperature and the powder retained its activity for years. it had ng effect when injected into animals other than chickens, and it always produced the same type of tumour. , as the same result could not be obtained with a filtered extract of other malignant growths, this very important discovery was interpreted to mean that this fowl-sarcoma was a thing apart, although in structure and behaviour it closely resembled the mammalian sarcomata. subsequently, its discoverer found that two other malignant tumours of fowls possessed similar proper- ties, and quite recently carrel has recorded the formation of malignant tumours in fowls following local irritation of the tissues with tar or arsenic, filtrates from which were also infective for chickens. rous believed that the filterable agent which caused the tumours he studied was, probably, an extremely small microbe, but as he did not succeed in propagating it outside the body its nature remained undetermined. the nature of the in- fective agent in the filtrate of rous’s tumour has recently been disclosed by gye, who has succeeded in growing it in test tubes in a special medium. the culture has been carried on through several generations of transplantations. by this means the virus has been purified from the other constituents of the original im- plant. the inoculation of this purified virus alone did not give rise toa tumour, but if mixed with an extract of the fresh tumour, in which the virus had been killed by chemical agents and which alone was innocuous, a tumour occurred, in other words, the conjunction of two factors, living virus and some non-living chemical substance or substances, is necessary to provoke the cells of the animal to that anarchical development which is char- acteristic of malignant growth. gye’s experiments —gye has also succeeded in showing that chicken sarcoma is not peculiar, as hitherto believed, and that a particular mouse sarcoma will sometimes yield an infective filtrate. in this case, however, a special technique had to be employed, the original method of rous proving unsuccessful. this is a discovery of much significance and it seems probable that an extrinsic origin may be found in the case of other cancers in the near future. : the virus of rous sarcoma has been presumed to be par- ticulate as it is held back by the finer grades of filter, and recently barnard, using ultra-violet light, has obtained photo- graphs of small globoid bodies about o-1 uw in diameter from cultures of the virus. these small bodies occurred 1n masses, suggesting colonies. they were not discovered in the medium before inoculation or when the cultivation of the virus proved un- successful. whether they represent the microbes or aggregations of colloidal particles produced from the proteins of the medium by chemical changes associated with the growth of the virus occurring therein, is not at present determined. plant diseases.—filterable organisms are also responsible for many diseases of plants (see plant patholocy). in fact, their existence was first brought to light by iwanowski in 1892 in connection with the mosaic disease of the tobacco plant. iwan- owski’s discovery was lost sight of and the fact was rediscovered by beijerinck in 1898. many varieties of plants, including potatoes, tomatoes, beans, peaches, clover, peas, cucumbers, turnips, spinach, datura, hyoscyamus, capsicum, sugar-cane, 28 maize, sorghum and various grasses suffer from mosaic diseases. in most mosaic diseases the only obvious lesion is bleaching of the leaves in patches of varying extent, but sometimes, as in “leaf roll” of potatoes, “ curly top” of beet and “ spike ” disease of sandalwood trees, definite destruction of tissue leading to malformation occurs. the loss of chlorophyll interferes with the nutrition of the plant by limiting the leaf area capable of utilising the radiant energy of the sun for the building up of carbohydrate from carbonic acid and water. to this handicap local necrosis of portions of the leaf and stalk is in some varieties superadded. the economic effect of these diseases may be, as in the case of the mosaic of sugar-cane, almost negligible or, as in the case of “ peach yellows ”’ and the “ spike” of sandalwood, serious, as it destroys these trees. between these extreme instances, the infection results in more or less diminution of crop. only the growing leaves are affected. nevertheless the virus extends throughout the plant and some- times to the seeds. mosaic diseases are very infectious. mere handling of a healthy plant after touching an infected one is, in some instances, sufficient to transmit infection. the disease is spread by leaf flies or beetles and by grafting (see entomology, economic). the virus is not capable of maintaining itself in the soil. there is a large number of different viruses which produce mosaic diseases. some of them infect more than one species oi plant. they can also inhabit resistant species of plants without these manifesting any symptoms, but the disease can be trans- ferred from resistant plants to susceptible species by insects or grafting. many attempts have been made to propagate these plant viruses in the laboratory upon plant-juices without suc- cess, but the virus of one of the mosaic diseases of the potato appears to have been recently cultivated by olitzky.. properties of micro-organisms.—little is known about most of these filterable viruses. they appear to be of various natures, and the only property common to them is minuteness. the parasite responsible for yellow fever is a small spirochacte, those occasioning bovine pleuro-pneumonia and human polio- myelitis are globoid in shape and just on the margin of visibility with the best microscopes. it is not improbable that many of them flourish only inside the cells of animals and plants, which may explain the difficulty in cultivating them in artificial media. in some cases, small bodies of definite size, shape and staining characteristics are always to be seen in the cells at the seat of the lesion (trachoma, molluscum coniagiosum, variola, vaccinia, bird-pox, typhus and rocky mountain spotted fevers). whether these represent the microbe or granules in the cell contents produced under the influence of the virus is a matter of opinion. until cultivation outside the body is achieved this controversy will not be settled. definite results —at present only the viruses of pleuro- pneumonia, poliomyelitis, yellow fever, chicken sarcoma and the microbe probably responsible for influenza have been cer- tainly cultivated, although many claims to have accomplished this with other viruses have been made. some of these viruses occur in the blood of the patient during the acute stage of the illness and are transported to a fresh host by the bite of blood- sucking insects. transmission of i nfection. —the infections of yellow fever (g.v.) and dengue are conveyed by the mosquito (stegomyia fasciata). that of papataci fever is transmitted by the sandfly (phiebotomus papatasii) (see sandfly fever) and that of typhus and trench fevers by lice (see infectious fevers). with these three fevers and also in the case of some of the mosaic diseases of plants which are transferred by leaf flies, some days elapse before the insect 1s capable.of handing on the infection, indicating that an interval for the multiplication of the parasite is necessary. it is possible that a stage in the life-history of the parasite can only occur in the body of the insect host. some filterable viruses, such as smallpox, cow-pox, foot-and-mouth disease and molluscum contagiosum give rise to superficial lesions, and are spread by contact; others occasion catarrh of the respira- tory passages and are distributed by coughing and intimate con- tact, as in distemper, measles and pleuro-pneumonia. filtration conclusion.—most filter-passing microbes which have been discovered hitherto cause disease of plants or animals. it would be strange if only parasitic forms existed, for the majority of the larger microbes are not pathogenic but are concerned with the multifarious putrefactive and fermentative changes in organic matter on the surface of the earth. accordingly, it would be natural to suppose that sub-microscopic germs with similar activities would be ubiquitous. the indications, at present, are, however, against this supposition, and sub-microscopic dimen- sions seem to be an attribute, more especially, of germs which are parasitic upon animals and plants. (c. j. m.*) filtration.—in many industrial processes it is necessary to separate finely divided solid materials from liquids. the process of filtration consists in passing the liquid through a porous medium, which retains the solid particles. in some cases this is done for the sake of purifying the liquid; in others the recovery of the solid is the main object. many different types of filter are in use, and it is necessary to consider (1) the various porous ma- terials which are available for filtration, and (2) the construction of the apparatus in which these are applied. filter materials —the following are the main types of ma- terial which are in use: 1. sheets of woven or felted material. these comprise porous filter paper, cotton, woollen or linen cloth, felt and woven metal. 2. unwoven fibrous material, such as cotton wool, linen fibre, cellulose pulp, metal fibres, sponge. 3. granular or powdered materials, such as gravel, sand, earth, coke, sawdust, cork. 4. porous plates of stone, porcelain, carbon, silica, etc. the choice of material depends upon (a) the fineness of the substances to be filtered, (5) the chemical nature of the liquid, (c) convenience in collecting the solid material after filtration. laboratory filtration—porous paper is generally used as the filter medium, being resistant to most of the liquids which require filtration. the commonest method of filtration is to fold a cir- cular filter paper twice at right angles, and open it out to a cone with three thicknesses of paper at one side and one at the other. this is placed in a conical glass funnel, and the jiquid is poured into it. in some cases, the filter funnel is provided with a hot-water jacket to keep the liquid warm during filtration. filter paper is also manufactured in the form of thimbles, for extractions with solvents, such as alcohol and ether, in special apparatus. the buchner funnel is made of porcelain and has a flat, per- forated bottom on which a circular filter paper is placed. this form of filter has the advantage that the filtration may be assisted by the application of suction below the filter. the gooch crucible is a porcelain cup with a perforated bot- tom. a thin layer of asbestos serves as the filter, and the crucible can be weighed, after drying, to ascertain the weight of solid material collected. a recent advance in laboratory filters consists in the use of discs made up of a fritted mass of hard glass, which has been ground and sieved to a definite degree of fineness. these are fused into various types of glass apparatus, and are resistant to almost all chemical reagents. filtration of drinking water—domestic filters are usually supplied in the form of earthenware vessels with a filter bed of charcoal; in some cases filters of paper, asbestos or stone are used.” it was originally thought that charcoal filters would unfailingly remove micro-organisms, but the action was sub- sequently found to be less complete than had been believed. indeed, if the filter material be not removed at intervals, it may become the seat of organic growths. large-scale filtration of town supplies of water is generally effected in sand filters. industrial filtration—when possible, it is advantageous to allow the solid precipitate to settle in the liquor for some time, and to run off as much as possible of the clear liquid. the sediment may then be stirred up with water, allowed to settle, and the liquid again decanted, so as to minimise the bulk of liquor to be filtered, and to facilitate the subsequent washing. the design of industrial filters varies according to the require- ments. the chief considerations are that the filter shall present finance—finland a maximum available surface without occupying too much fac- tory space, that it shall withstand the required pressures, that it shall not be easily clogged, but shall be readily cleaned and easily controlled at all points. in some cases, continuous work- ing is desirable. simplicity and economy of construction often outweigh all other considerations, and for many purposes it is sufficient to filter through a bed of sand, or through a simple sheet of cloth resting on a flat, perforated support. suspended bags of cloth are also frequently used, and have the advantage that the bag can be squeezed or wrung out after filtration to remove as much liquor as possible from the solid material. vacuum filters—as in laboratory filtration, suction is fre- quently applied to accelerate the flow of liquid. a filter cloth is spread on a perforated plate of earthenware or other material, and the receiver into which the filtrate flows is connected with a vacuum pump. conversely, pressure may be applied to the surface of the liquid in the filter. in place of cloth filters, porous plates are sometimes used; these may be either flat plates or cylindrical “‘ candles ” of porous material, presenting an increased filter area. 7 leaf filters may be used either for suction or pressure. a typical form of leaf consists of a rectangular frame of perforated pipes to which is attached a stiff, corrugated surface of coco-nut matting or other material, and the whole enveloped by a cloth bag. the liquid passes from the exterior to the interior of the leaf, and is assisted either by external pressure or by internal suction. a filtering unit consists of a number of parallel leaves, and thus presents a large filtering surface. filter presses are somewhat similar in principle. in one form, a number of recessed plates are supported on a framework, so that they can be firmly pressed together by a screw press. sheets of cloth are placed between the plates, and thus, when the filter press is assembled, it forms a series of narrow partitions separated by cloth filters. channels are provided so that the sludge to be filtered can be forced under pressure between the cloth sheets, and the filtered liquid is collected from taps at the bottom of the plates. after filtration, the plates are separated, and the cake of solid material is removed. in place of recessed plates, some filter presses have alternate plates and distance frames. in centrifuges the filtration is assisted by the rapid rotation of a circular pan. the periphery of the pan is perforated, and provided on its inner side with a filter cloth, supported by a basket of metal. the rapid rotation (up to about 1,000 revolu- tions per minute) whizzes the hquid through the filter, with a force several hundred times greater than in gravity filtration. in the above-mentioned filters, the solid material has to be collected at intervals, and this necessitates stopping the filtering operation. continuous filtration can be effected by rotary filters. a hollow drum is supported in such a way that it can be rotated on a horizontal axis. the periphery of the drum is covered with a filter cloth, and the drum dips into the liquid to be filtered. by suction, the liquid is drawn through the filter cloth to the interior of the drum, and the solid remains on the outside. the drum rotates slowly, and a scraper is fixed in such a position that it scrapes off the solid material continuously. a recent advance in filtration methods is the stream-line filter, which permits of the separation of extremely finely divided solid matter, which would pass through ordinary filter cloths. a large number of sheets of paper are pressed together, and the liquid is forced through the edge of the pack by the application of pressure. the channels between the shects are so minute that the finest precipitates are retained. the filter 1s made in various forms to permit of continuous filtration, etc. aids to filtration.—the greatest difficulties in filtration are presented by slimy substances, which clog the filter. applica- tion of increased pressure only accentuates the difficulty, and considerable importance attaches to methods whereby the slimy material may be caused to clot together and settle out. this can be effected by the addition of kieselguhr, fuller’s earth, clay, talc, silica-gel and warious carbonates. another procedure is to coat the filter with a layer of finely divided kieselguhr, 29 boneblack, sawdust or other finely porous material, which re- tains the slime and prevents it from penetrating into the filter material. (r. c. f.) finance: sce banking; currency; and the sections on national finance in france; germany; great britain; united states, etc. , ?