FUEL PROBLEMS

the wood of our forests is our natural fuel. if we were restricted to that material, the enormous fuel demands of our industrial age would long since have razed our forests. as the dearth of wood made itself felt in industrial districts, recourse was had to the fossil fuels which nature has stored up, coal and peat, and natural oil and natural gas. bituminous coal was the most important of these fuels, and the iron industry required in particular those coals which gave a metallurgical coke suitable for replacing the wood charcoal in the blast furnace. in some countries, for instance in germany, brown coal has of late almost broken the predominance of bitu- minous coal; brown coal is more easily mined and offers advan- tages as household fuel when briquetted. further, modern industry and transport, established on the coal-fuel basis, have recognised the advantages of liquid fuels and their necessity for certain purposes. oceanic navigation makes an increasing use of crude oils; automobile and aerial motors are no longer to be thought of without gasoline fuel. again, the cleanliness and precision attainable with gaseous fuels in furnaces and in the preparation of valuable products, have secured to these fuels a preferential position in the produc- tion of steel and in the manufacture of glass and of ceramic objects. extensive systems of gas-pipes distribute gas through towns and industrial centres, even across states. 125 but the natural fuels, solid, liquid and gaseous, are by no means evenly distributed over our globe. consequently we are forced to produce the required fuel trom other sources, to meet local conditions, unless we are satisfied to depend upon im- ported fuel. the chemist and engineer are hence confronted with the problem of converting fuels of locally lesser value into fucls for which there isa greater demand. thus arise mar y prob- lems, the most important of which is the conversion of coalinto oils. i. gaseous fuels and their production from solid fuels—the constitution of the gaseous fossil fuels is easily determined; for the molecules of gaseous sub- stances are generally the smallest and the least complex. the combustible constituents of natural gases, exhaled as natural gas or fire-damp, are almost exclusively represented by methane, ch, the methane may have originated from residues of a fossil flora or fauna. the biological processes which resulted in the formation of petroleum took place under scission of methane, which was also produced during the formation of coal and dur- ing its natural ageing. natural gas is therefore found in associ- ation with oil-fields and coal seams. as, however, natural gas is not replenished at the rate at which it is consumed in some industrial districts (e¢.g., pennsylvania), many works which originally relied upon natural gas have been obliged to adopt producer gas as their fuel. the chemical constitution of gaseous fucls is easily ascertained, and also the production of gaseous fuels from liquid and solid fuels offers no particular difficulties. dry distillation —fyor the preparation of gaseous from solid fuels two chicf methods are now available. the so-called dry or destructive distillation of coal is historically the first. the gas formed by the thermal decomposition of the coal consists, when the temperature 1s kept as low as possible, essentially of methane and other hydrocarbons. when the coal is discharged into glowing retorts, as in gas and coke-oven works, the gas liberated will be the richer in hydrogen the higher the tempera- ture. this method of coal distillation furnishes a gas of relatively high calorific value. with low temperature carbonisation, the calorific value may rise to 9,000 calories per cu. metre; at higher temperatures, the figure will lie bet ween 4,0oco0 and 5,000 calories. but the volumes of gas'are comparatively limited; only a small portion of the coal substance is gasified, the bulk being trans- formed into coke. the yield is about 60 to 70 cu. metres of low temperature gas per ton of gas coal, and some 2c0 or 300 cu. metres of coke per ton. the complete gasification of coal can- not be effected by heat alone. the coke produced by the dis- tillation must be gasified by chemical reactions. this can be done in three ways. chemical reuctions.—the reaction of air with white-hot coke yields a gas, theoretically consisting of two parts of carbon monoxide and four parts of nitrogen; this gas is of low calorific value. the reaction 2c-+o.=2co proceeding under consider- able liberation of heat, the manufacture of such a gas—air- gas—can be easily carried out continuously in shaft furnaces. the best material is coke; coal may be used provided it does not cake; brown coal briquettes are also suitable. from the standpoint of gas production, the ordinary pig-iron blast fur- nace may be regarded as a huge air-gas producer, with the dif- ference that the oxygen required for the production of carbon monoxide is taken not only from the blast, but also from the iron ores. this process of coal gasification, the air-gas process, is associated with a pronounced liberation of heat. iv ater-gas process—in the water-gas process, however, the reaction c-+h.o=h:+co, heat is consumed and has to be replenished to sustain the process. the water-gas process can therefore not be carried out continuously in a shaft furnace unless external heat be supplied. the process is hence worked discontinuously. during the first hot run the coke charge is raised by the air blast to a temperature of about 1,000°c.; steam is then admitted, heat is absorbed and water-gas is pro- duced, while the temperature of the layer of glowing coke sinks gradually. when the temperature has fallen a few hundred degrees, the hot-air blast is again turned on. 126 mixed gas process—since the air-gas process liberates heat whilst the water-gas process absorbs heat, technical practice began to combine the two processes before the theory of the reactions was understood. gas generators were worked with air and steam. numerous advances have been made during the last decade in the domain of fuel gasification, particularly with regard to the difficulties caused by the use of coal instead of coke in the generation of both mixed gas and water-gas. | by the use of considerable additions of steam we have, in the mixed gas process, further learnt to recover the bulk of the nitrogen contained in the coal, in the form of ammonia (see am- monia). success has also been achieved in the perfection of gas producers as economical apparatus for the manufacture of primary tar. the total gasification of the coal and coke has so far laboured under the disadvantage that, as the daily through- puts of gas producers were relatively small, a good many furnace- men and a good deal of stoking were required. recently gas generators have been built for daily throughputs of 100 tons. this working in large units is one of the most important prob- lems of coal gasification. from liquid fuels ——further substitutes for natural gaseous fuel can be obtained by the thermal decomposition of liquid fuels, such as crude oils or certain fractions of these oils, gas oil, tars or tar-fractions. the carburation of water-gas is a case in point. water-gas does not burn with a luminous flame and its calorific power is low; it is therefore carburated by the injec- tion of crude oil or tar oil into incandescent chambers. at tem- peratures above red glow the oils are decomposed, to a large extent, into gases, some tar and coke. the gases consist of very diverse hydrocarbons of higher calorific values than the water- gas. by mixing the two kinds of gases the water-gas is therefore enriched. in the early days the gas was carburated also for the purpose of rendering it luminous. with the invention of the welsbach incandescent burners this application has lost its importance; but carburation for the sake of increasing the calorific value still remains important. the thermal decomposition of oils is practised for the general purpose of obtaining gases of high calorific power. thus tar or oil gas is manufactured by the decomposition of so-called gas oil. it served chiefly for lighting railway carriages, but is being replaced by electric illumination. the gasification of liquid, relatively inferior fuels, by the aid of steam might be- come valuable under certain conditions for the preparation of a water-gas rich in hydrogen, by a kind of water-gas process. thus, petroleum vapours mixed with steam and heated to 1,000° in the presence of bauxite as catalyst can be converted into a mixture of carbon monoxide and hydrogen, which high-pressure catalysis further transforms into synthol and similar products. from other gaseous fuels —it may happen that natural gas is available, but that hydrogen is needed. the conversion of methane into hydrogen may be effected catalytically by passing methane through tubes or kilns at the high temperature of 1,000°, when methane is decomposed into hydrogen and car- bon. at lower temperatures the decomposition is incomplete. when shaft furnaces are used the carbon deposited can subse- quently be burnt out again by blowing hot air into the furnace; the heat liberated is re-utilised to raise the furnace again to the high temperature and to decompose more methane. like the vapours of liquid fuels (though less easily, owing to its high stability) methane can also be converted, by means of water vapour in the presence of bauxite as catalyst at about 1,000°, into a mixture of carbon monoxide and hydrogen. the reversed process should finally be mentioned. if desired, the carbon monoxide contained in some available fuel gas mix- ture can be removed by transforming the carbon monoxide catalytically, at low temperature, into methane, with the aid of the hydrogen in the mixture. this was done experimentally about 1915. the process has not been adopted, however, although the elimination of the monoxide from illuminating gas seemed hygienically advantageous. the catalytic preparation of pure methane from water-gas, tried on an industrial scale some years ago, still remains in the preliminary stage, because fuel problems the purification of the gas (of sulphur) and the partial removal of the carbon monoxide proved too expensive. such a process, moreover, involves a loss of about 25% in calorific value, because the proportion of methane, represented by the theoretical mix- ture of carbon monoxide and hydrogen, possesses only three- quarters of the heat value of the four times larger volume of (co+3h,) which it replaces. the reason is that this methane formation is a strongly endothermic process. purification of gaseous fuels —for many purposes the arti- ficial gaseous fuels require careful purification. thus, the gas escaping in large volumes from the mouth of a blast furnace has to be freed of all the dust it carries before it can be fed into internal combustion engines. the object is attained by mechani- cal cleaning and dust separation, by means of filters, centnfugal machinery or sprinkling with water. the electric dust precipi- tation by the cottrell process should especially be mentioned (see fume precipitation). the removal from the gases of the sulphur compounds is frequently a difficult problem. it is chiefiy required in the case of illuminating gas, and the sulphur can be recovered in a utilisable condition. the old-established method purifies the gas by means of iron ore (bog ore). activated car- bon has recently been experimented with for the same purpose. the gas is mixed with a sufficient amount of air to oxidise the sulphuretted hydrogen in the gas into sulphur; the sulphur is retained by the carbon, and the process is accelerated if ammonia is present in the gas. the activated carbon impregnated with sulphur is then extracted with ammonium sulphide; the evapo- rated solution leaves the sulphur as a marketable residue. for most of the catalytic processes removal of hydrogen sulphide alone from the gas is, however, insufficient. the other sulphur compounds, notably carbon disulphide, must also be eliminated. ii. liquid fuels and their production the natural liquid fuels, natural oils or petroleums, occur in widely-diverging compositions, and are partly aliphatic, partly naphthenic in character; aromatic compounds are found in some kinds of petroleum. the natural oils are also classified accord- ing to the nature, asphaltic or paraffinic, of their high-boiling residues. as regards the origin of petroleum, the biological hypothesis of engler has found general support. according to this, petro- leum was formed in the course of time by the decomposition of the fatty constituents of small and large organisms. the optical activity of certain petroleum fractions is regarded as affording a strong argument in favour of this view. that, however, liquid hydrocarbons, with which we are essentially concerned, may be prepared artificially in other ways and might naturally have been produced in such ways under certain conditions, has been established within this century, by chemical research in various cases. there are, e.g., carbides, such as uranium carbide, which liberate liquid hydrocarbons when decomposed. it is further known that acetylene and hydrogen may catalytically be com- bined to form petroleum-like products; and within the last few years it has been shown that the high-pressure synthesis of water-gas leads to the formation first of synthol and further, when this synthol is heated under pressure, of an artificial petroleum. whether or not petroleum has been formed in some localities by inorganic reactions of cognate nature, cannot be proved, but the possibility cannot be excluded. from solid fuels —ueating of geologically recent coals under exclusion of air seems to be the simplest method for the produc- tion of liquid fuels from solid fuels. destructive distillation yields, in addition to the gases mentioned and to the residual coke, a tar which, when formed at low temperature, contains constituents of petroleum character. the proportions of such tar obtainable are considerable. gas coals of more recent geo- logical periods (ordinary coal) yield up to 12% of the tar, cannel coals still more. certain lignites and oil shales are likewise suitable materials for the manufacture of the tar by distillation. the scottish shale-oil industry and the brown coal carbonisa- tion works of central germany operate on these lines. the large bulk of the tar which comes from our coal gas and fuel problems coke works is of a different composition. owing to the high temperatures which are used in gas-works and especially in coke- ovens, in order to secure high yields of both gas and a firm coke, the tars are essentially aromatic in character and rich in ben- zene, naphthalene, anthracene, etc. by weight the chief product is in either case semi-coke or coke. the tar yield referred to the weight of coal, lies in general between 12 and 3% (see coal tar propucts). bergius process.—since coal contains only 5% of hydrogen on average, whilst petroleum contains more than twice as much, an increase in the oil yield from coal seems dependent upon a supply of hydrogen. in the bergius process for the liquefaction of coal, hydrogen is made to react with coal at a pressure of more than 100 atmospheres and at temperatures of about 450°. the coal is ground and kneaded with 30% of tar into a paste; this paste is continuously pressed into the high-pressure auto- clave. we may imagine that the coal is first carbonised, the temperature being sufficiently high for this purpose; the prod- ucts are primary tar and semi-coke. the semi-coke is further hydrogenated and half of it, by weight, is converted into oil. that the reaction may proceed in this way has quite recently been established by experiments in which the carbonisation was effected at ordinary pressure, and only the hydrogenation of the semi-coke was carried out at high pressure. this “ ber- giannisation ” is not equally applicable to all types of coal. suitable materials are particularly coal of comparatively recent periods, rich in volatile constituents, but not inclined to cake. such coals which are popular as fuel for gas generators, but in general unsuitable for coking, yield about 50% of oil by the bergius treatment, whilst low-temperature carbonisation would at the best give 10 to 12% of oil. the oil of the bergius process is not equal in value to natural oil. it contains, it is true, ample proportions of gasolene, but it also contains about 20% of phenolic constituents, and is hence more closely related in con- stitution to the primary tars than to petroleum. the bergius process, which is expensive owing to the high-pressure apparatus required, offers advantages in localities in which there is no market for semi-coke, neither as domestic fuel nor for gasifica- tion or the manufacture of powdered fuel. under other con- ditions, improved methods of low-tempcrature carbonisation will be scrious competitors. from other liquid fucls.—natural, as well as artificial liquid fuels contain in general fractions of almost all boiling points, ranging from ordinary temperature up to 4oo°. not all these fractions are, however, in equal demand. in the rgth century lamp and illuminating oils, boiling between 150 and 250°, were the most valuable petroleum constituents. since then electric and incandescent lighting on the one hand, and the develop- ment of automobiles, flying machines and industry generally on the other, have increased the values of the low-boiling ben- zenes and of the lubricating oils in petroleum, so that the evalua- tion of the various petroleum fractions has altogether changed. at present the supply of benzene from petroleum is not sufficient to satisfy the demand. fortunately the high-boiling constitu- ents of petroleum can be converted by cracking processes into low-boiling motor spirits. one-third of the gasolene wanted in america for automobiles is said to be now produced by cracking. like the oil-gas production mentioned above, cracking involves heating of high-boiling oil fractions up to incipient decomposi- tion. the cracking process is, however, conducted at lower temperatures, in the neighbourhood of 500°, and under pressure, because less gas and more vapours of gasolene type are formed when the pressure is raised. this heating up to partial thermal decomposition of oils of high boiling points is important in other respects. in the diesel motor (see internal combustion engine), it is believed, the air is first heated by the compression stroke to cracking temperatures; the oil injected into this hot air is then thermally decomposed and burns in the compressed air; separate ignition of the fuel can be dispensed with. the dearth of low-boiling gasolene has induced designers of automobile internal combustion engines to use fucls con- taining high-boiling constituents. these constituents, how- 127 ever, are apt to ignite by the heat due to compression toward the end of the compression stroke and before the dead point is passed. the piston is then forced back and “‘ knocking ” occurs. this pre-ignition of gasolene-air mixtures seems to be favoured, if not caused, by the fact that the carbon deposited on the engine cylinder always carries some iron. the tendency to knocking is suppressed by adding to the motor spirit substances such as lead tetra-ethyl which, it is assumed, act by being adsorbed by the ferriferous carbon in the cylinder; the carbon js thus catalyt- ically poisoned and cannot produce knocking. the anti- knocking reagents are, however, dangerous to the human sys- tem, and not likely to find favour. the best way of stopping the knocking trouble would be to return exclusively to motor fuels of low boiling points. the world’s production of benzene is in- suflicient for the demand. synthetic preparation of benzenes may bring the desired solution of this problem. some artificial liquid fuels can or should be improved or modi- fied, wholly or partly, before utilisation. half of the oil fraction of primary coal-tar consists of phenols for which there is little demand. by means of hydrogen at 700 to 800° they can be reduced to the more valuable benzene and toluene. certain hy- drocarbon fractions of primary tars are highly unsaturated; they can be hydrogenated and rendered more valuable in similar ways. the naphthalene of coke-oven tar can be converted into a liquid fuel, tetrahydronaphthalene, commercial tetralin. for this purpose the solid naphthalene is fused, purified by crystalli- sation and freed of the last traces of sulphur by treatment with metallic sodium. the naphthalene thus purified is then sub- mitted to hydrogenation by means of hydrogen under pressure in the presence of nickel as catalyst, somewhat as in oil harden- ing; but the product, tetralin, is liquid. attempts have also been made to convert high-boiling liquid fuels and also tar and pitch into low-boiling motor spirit by the bergius process, analogous to cracking but combined with hydro- genation. the process has not found industrial application, apparently because the american cracking processes attain the same object by less expensive means. from gaseous fuels—gascous fuels frequently contain vapours of liquid fuels of low boiling points. natural gas, for example, very frequently, though not always, carries higher homologues of methane. there are benzene vapours in coke- oven gas, and the gases of low-temperature carbonisation retorts contain vapours of benzene character. ‘these vapours can be removed and recovered by physical methods, scrubbing the gas with oil or treatment with adsorbents, such as activated carbon and recently also silicagel; the use of the latter reagent is so far largely experimental. ‘these vapours are further con- densed by cooling or by compression, or by a combination of the two methods. both methods yield the liquid directly; in the former cases the oil or activated carbon used for the scrubbing or adsorption must afterwards be submitted to steam blowing in order to obtain the liquids. | the object of these processes is simply the recovery of fuels of low boiling point already present. methods for the synthetic preparation of such fuels have been developed within the past few years. the process is a high-pressure catalysis, starting with carbon monoxide, utilised suitably in the form of a mixture of monoxide and hydrogen, a water-gas containing an excess of hydrogen. a mixture of one part of carbon monoxide and two parts of hydrogen is first carefully purified, especially of all sulphur compounds, and then compressed to about 150 atmos- pheres. at this pressure and a temperature of about 400°, the mixture is passed over the catalyst, for instance, zinc oxide or chromium oxide. the hydrogen is bound by the carbon monox- ide and the reaction co+2h2.=ch;0h yields almost pure methyl alcohol. provided disturbing metals, particularly iron which would form iron carbonyl, be absent, no undesirable secondary reactions likely to diminish the alcohol yield seem to take place. formation of methane, an undesirable reaction, would be aidled by the presence of iron. this synthesis of methyl alcohol hardly concerns the fuel problem. the alcohol contains almost 50% of oxygen, its 128 calorific value is about half that of benzene or gasolene, and it is not a motor fuel. higher alcohels—in the case of the higher alcohols, it is pos- sible to prepare mixtures of those alcohols and ketones by high- pressure catalysis, starting with the same raw materials, carbon monoxide and hydrogen, but resorting to other catalysts. these alcohol mixtures of oily character (¢.c., little soluble in water) which may be designated by the general term “ synthol,”’ can, for instance, be produced with the aid of iron impregnated with po- tassium carbonate as catalyst. ninety percent of this synthol boils below 200°, and it forms an excellent motor fuel, at least equal in value to benzene and gasolene. jor the present the syn- thol process is too expensive. but in the future synthetic motor fuels must be prepared in this or similar ways. water-gas can be produced from all types of coal and peat. it is therefore pos- sible to manufacture synthetic motor fuels in all districts where some coal but not petroleum is available. this source of fuel would provide for the time when petroleum and petroleum prod- ucts fail. we have more reliable knowledge as to the occurrence of coal than about oil-fields. the coal resources of the globe will probably hold out for many centuries. wi, solid fuels and their production so far man essentially relies on fossil, chiefly solid, fuels for obtaining heat and power. chronologically these fucls may be classified as peat, brown coal and coal. <a discussion of their genetic interrelations is unnecessary. the earlier view which traced the genesis of coal to cellulose is giving way. microscopi- cal examination of coal indicates that coal is the decay-product of wood. decay of wood, biological researches teach us, is due to certain fungi; they work by destroying the cellulose, which is transformed into gaseous and water-soluble products, whilst they leave the lignin essentially intact. chemists have proved that the lignin and the carbon constituents proper of brown coal and coul possess a similar chemical constitution, that is to say, a cyclic structure. the assumption is, then, that the main constituents of our fossil fuels have been formed by a slow decay of lignin, during which the essential chemical character of the lignin was pre- served. cognate interesting conclusions have been arrived at concerning the bitumen in coal. it would appear that the bitu- men of the highly diverse brown coals consists mainly of fatty acids of high molecular weights and of odd numbers of carbon atoms, whilst the biologically easily digested fatty acids, which predominate in the fats of plants and animals, contain an even number of carbon atoms. we may hence assume that the fatty acids of the mother substance of coal, which are easily destroved in a living organism, have disappeared, whilst the more resistant fatty acids of odd carbon-atom numbers have survived and have been utilised in the formation of bitumen. the solid fuels—coal, for example—cannot always be used in the form in which they are won. according to requirements solid blocks are broken up and sifted into the desired sizes, or ground up and atomised to yield convenient powdered fuels. conversely, small coal is rendered more marketable by briquet- ting; this applies particularly to the lignites, whose moisture of 50% is first recluced to 15%. apart from these mechanical modifications, other methods of improving solid fuels have of late acquired importance. metal- lurgical coke was first made in coke ovens merely as a substitute for charcoal. the enlargement and perfection of the blast fur- nace called for a firm, little breakable and friable coke. then the quality of the coke had to meet higher claims. what is wanted is absence of sulphur compounds. to a slight extent the sul- phur is removed with the pyrites when the coal is washed. a complete elimination of the sulphur has been attempted by treat- ing glowing coal with hydrogen; the process has not yet been adopted, chiefly, perhaps, because the purification is not com- plete, in spite of its high cost. meanwhile, however, ways have been discovered of controlling the combustibility of the coke. the blast furnace requires an easily combustible coke, the cupola a coke which burns slowly. the former coke can, in general, be puller-fume. precipitation, heectrigal obtained by accelerating the coking process and by avoiding subsequent heating, whilst high coking temperatures and long coking periods favour the formation of a sluggishly burning coke. the semi-coke obtained when temperatures of 500 to 600° are not excecded in its production is readily combustible. if in a handy, dense and little friable condition, this semi-coke, the so-called smokeless coal, would represent an ideal fuel. to produce such a semi-coke which will not require subsequent bri- quetting is one of the most important problems of the future; considerable progress has been made in the solution of this prob- lem during the past few years. the production of solid from liquid fuels is, as a fuel problem, a matter of secondary importance. retort graphite is produced by decomposing the tar vapours and the hydrocarbons of gas in gas retorts. petrol coke, so-called, is obtained by coking petroleum pitch. both these cokes are products of considerable value for the manufacture, e.g., of carbon electrodes; but they do not count as fuels. the soot prepared by the decomposition of vapours of liquid fuels, a high-priced form of carbon, js also utilised in the manufacture of electrodes. reference should finally be made to the preparation of solid from gaseous fuels. here again a soot process should be men- tioned in the first instance. carbon black is obtained by the incomplete combustion of natural gas; the process is wasteful, however, and is only applied when the gas cannot be utilised in other ways. better results can be secured by the catalytic decomposition of carbon monoxide. this method has not yet found any serious industrial application, but it deserves atten- tion in cases where a carbon absolutely free of sulphur is wanted. the process might be developed in promising directions, since the decomposition of the monoxide 2co=c+coz yields car- bon dioxide which cyclically can be reduced to monoxide again. ‘the essence of the process is therefore an intermediate gasifica- tion of impure coke for the preparation of pure carbon. see “fuel and power gencration,” in rogers’ manual of in- dustrial chemistry (4th ed., 1925). (f. fr.) fuller, john frederick charles (1878- ), brit- ish soldier, was born sept. 1 1878 and gained a commission in the oxfordshire and buckinghamshire light infantry 1898. after active service in the south african war, he relieved the tedium of peace-time soldiering by extensive scientific and philo- sophical studies, and gained a considerable reputation as an authority on hindu mysticism and the iiebrew kabbalah. these studies provided an unusual groundwork and mental equip- ment for his military researches later. in the world war, after holding a variety of staff appointments, he became chief general stafl oflicer of the tank corps in april 1917. he had a responsi- ble share in the project for the great tank surprise at cambrai in nov. 1917, and in the tank successes later, until in july 1918, he was brought back to the war oflice to organise the vast tank expansion then contemplated for 1919, had the war continued. developing his ideas after the armistice and preaching his new gospel of war, colonel fuller was for a time criticised as a tank extremist, an unpractical visionary. abroad, however, his views were acclaimed, by the french gencral staff, who trans- lated and circulated them throughout their army, as “ an exact vision of the future.”’ gradually, however, his prophecies and his teaching permeated the army, gaining power from his ap- pointment, in 1922, as chief instructor at the staff college, and still more when, in 1926, he was appointed military assistant to the new chief of the imperial general staff. the result of his researches into the science of war is incorporated in his founda- tions of a science of war (1926), and among numerous other books, his tunks in the great war (1920), the reformation of wer (1923), and sir john moore’s system of training (1925) attracted wide attention (see strategy). fume precipitation, electrical.—the precipitation of smoke by electricity was described in 1824 by hohlfeld, a teacher of mathematics in leipzig, but only after it was inde- pendently rediscovered and critically studied by sir oliver lodge about 1884 did it attract gencral attention and lead to attempts at industrial applications. at the time, however, fume precipitation, electrical these proved unsuccessful due to the lack of modern equipment. it was not until 1906, following experiments at the university of california, that the process was commercially successful. the first installation was at the selby smelting works, near san francisco, where it was used for the removal of sulphuric acid mist from about 3,000 cu. ft. of gases per min.; it was still in operation there in 1926. by 1910 a plant to remove dry dust and fume from 250,000 cu. ft. of gas per min. was built at an- other smelter, and in 1912 the process was successfully extended to the removal of cement dust at nearly a red heat from 250,000 cu. ft. of gas per min. at the riverside portland cement com- pany. this mill, of 2,500 bbls. daily capacity, situated in the heart of the californian orange groves, had been threatened with legal closure as a nuisance because of the dust emitted. the electrical method as there installed removed 98% of the dust, the daily catch being about too tons, aggregating for these 13 vears of operation over 350,000 tons, equivalent to a train of fully loaded freight cars 100 kilometreslong. although first applied to mitigate nuisances, the demand for the process to-day is s insulator a ty i ie i yy as gas discharge service lines electrode commutator| \ me treater synchr. | ay mator f] hv/ = : ge 2) io =5 raw por’ e cas n q at transformer ground . fic. 1.—-apparatus for the electrical precipitation of dust or smoke from gases. primarily based on a greater profit to be derived from the gases cleaned or the material removed. at one time during the world war, even the riverside plant was making more profit from potash incidentally recovered in its dust than from its cement. research corporation.—another circumstance aiding the de- velopment through friendly public interest was the creation in 1912, under the auspices of the smithsonian institution, of the research corp. in new york city, to hold and administer as an endowment for research most of the united states patent rights to the process. the corporation besides supervising construc- tion and development of this particular process, also serves in general as a clearing house for information and as an intermedi- ary and trustee between inventors, the industries and the public. the process.—technically the process consists in securing a uniform, copious but non-disruptive discharge of electricity from small electrode surfaces of one polarity into a stream of cloudy gas. the fine solid or liquid particles composing the dust, fume or smoke are immediately attracted to, and deposited on, large clectrode surfaces of opposite polarity, the particles having become charged from the condensation on their surfaces of a portion of the electricity passing between the electrodes. the process is diagrammatically illustrated in fig. 1. alternating current from service lines is stepped up in a transformer to a high voltage and then converted to a direct, or rather a pulsating unidirectional, current by a commutator or “ rectifier” driven by a synchronous motor. one side of the line is grounded and connected to a pipe or “‘ treater ” carrying the fume-laden gases. this pipe serves as the collecting electrode. the other side of the line terminates in a wire serving as the discharge electrode, which is hung axially within the pipe. voltage is regulated to secure as strong a glow as corona discharge from the wire electrode as possible without passing over into a disruptive discharge, 2.e., a spark or arc. this adjustment is easier when the discharge electrode is the negative, though either polarity may be used. 129 the gas treaters now in general use consist either of a multi- plicity of pipes similar to that in the figure, or of plates hung vertically in a flue, the wires being stretched parallel between them. the materials of construction, including the collecting electrodes, vary from iron and lead to reinforced concrete and vitrified earthenware, depending on the composition and tem- perature of the gas stream to be treated. factors in design.—most plants are designed with electrodes of opposite sign 2 to 6 in. apart and operating at 30,000 to 80,000 volts. the size of installation is determined primarily by the volume of gas to be treated and the percentage of suspended matter to be removed, the amount, kind and size of particle of the latter being of minor importance. if p is the ratio of out- going to incoming suspended matter, / the average time in seconds that the gas remains between the electrodes, and a, a constant depending upon the apparatus, voltage, temperature and kind of raw gas, then p=k'. in most commercial practice ¢ averages about 2 seconds and k varies from 0-2 to o-7, the gases travelling from 10 to 40 ft. through the electric field of linear rates of 3 to 15 ft. per second. i.smoval of 90% to 99% of the suspended matter is usually aimed at, and the energy required is 1 to 3 kw. hours per 100,000 cu. ft. of gas treated. industrial uses.—the earliest applications of the process were to the smelting and sulphuric acid industries. installations in such plants in 1926 still outnumbered those in all other indus- tries, and amounted to several hundred scattered throughout the world. equipments at cement mills were fewer in number but handled a large volume of gas and a large tonnage of precipitate. other important applications are to the detarring of coke-oven gases, the cleaning of producer and iron blast-furnace gas, the cleaning of ventilating air in crushing, grinding and polishing mills (especially where cost of heating in winter makes recircu- lation of air important), the recovery of sludge acid fumes in petroleum refineries, the recovery of dust from brown-coal dry- ers, and the removal of ash from the stack gases of large power- plants burning powdered coal. on a laboratory scale the process has also been applied successfully to sanitary atmospheric analysis and to gas masks, including the removal of bacteria from air, but suitable standard equipment for these small-scale uses is apparently not yet on the market. the process in itself precipitates only suspended solid or liquid particles and makes no separation between gases. it has, how- ever, an important indirect application to problems in this latter field, involving the recollecting of solid or liquid absorbents which have been dusted or sprayed into gas mixtures. the electrical demulsification or dehydration of crude petroleum and trans- former oils, the separation of fine suspensions, such as clays in pure water and other poorly conducting liquids (electrical os- mose or electrophoresis) and electrostatic concentration of ores, though dependent on some of the same natural phenomena, differ to such an extent, in principle and equipment required, from the process here described as to preclude their discussion under this heading. bibliography.— evald anderson, trans. amer. inst. chem, eng., vol. 16, pp. 69-86 (1925), describing theory of comparative efficiencies of the electrical and other methods; h. j. bush, jour. soc. chem. ind. (lond.), vol. 41, pp. 22t~-28t (1921), giving history, theory and recent british practice; f.g. cottrell, jour. ind. @ eng, chem., vol. 3, pp. 542-50 (1911), also ann. report, smithsonian institution, for 1913, pp. 653-685 (chictly historical), and jour. ind. @ eng. chem., vol. 4, pp. 864-7 (1912), on founding of research corp.; w. deutsch, zeitschrift f. technische physik, vol. 6, pp. 423-37 (1925), an experi- mental and detailed theoretical study; d. b. dow, bulletin 250, u.s. bureau of mines (1926), on the electrical demulsification of oils; p, drinker, m. thomson and m. fichet, jour. ind. ifygiene, vol. 5, pp. 162-85 (1923), application to sanitary analysis of air; rk. durrer, stahl und kisen, vol. 39, pp. 1377-85, 1423-30, 1511-18, 1546-54 (1919), historically very complete and fully illustrated; m. hohlfeld, kasiner’s archi f. d. gesamte naturlehre, vol. 2, pp. 205-6 (1824), the earliest known reference; o. j]. lodge, jour. soc. chem. ind., val. §, pp. 572-6 (1886), the first comprehensive treatment of the subject; a. b. lamb, g. l. wendt and r. e. wilson, trans. anter. electrochem, soc., vol. 35, pp. 357-69 (1919), application to gas masks and bacteria; r. h. richards, vext book of ore dressing, pp. 253-5 (1925), on the electro-static concentration of ores; w. w. strong, chem. & met. eng., vol. 16, pp. 648-52 (1917), on general theory; f. supf and p. h. 130 prausnitz, ullmann’s encyclopddie der technischen chemie, vol. 8, pp. 599-607 (berlin, 1920), on electrical osmosce; it. a. winne, gen. elec, renew, vol. 24, pp. 910-21(1921), a description and rating of standard equipment. cfg. ©.) fundamentalism and modernism.—fundamentalism is the name given to a religious movement which, appearing in- dependently in different denominations in the united states during the period after the world war, steadily gathered momen- tum until in 1925 it became a subject of national, as distinct from denominational, interest through the trial and conviction of john t. scopes, teacher of science in rhea high school, dayton, tenn., on a charge of violating the tennessee law prohibiting the teaching of evolution in the state public schools. the trial began on july 10 1925, and was concluded on july 2t 1925, by the conviction of the defendant and his sentence to pay a fine of $100. the immediate issue was as to whether the defendant had or had not violated the provisions of the state law as to the subjects to be taught in public schools, but the wider issue was as to the extent to which the state, in its control of public education, may determine the nature of the religious instruction given to the students in its schools. the trial itself was the culmination of a movement which had been going on for some years. alarmed by the steady growth of liberal tendencies, the conservatives of the different churches had banded them- selves together to stay what seemed to them the rising tide of negation. the form of the movement differed in the different communions according to the particular issue which was in ques- tion at the time, but common to all the fundamentalist groups was, first, the acceptance of a view of the supernatural which insists that god manifests his presence in nature and history through exceptional and extraordinary activities, transcending the laws of nature; and secondly, the determination to use this conception of religion as a test to limit the freedom of teaching hitherto enjoyed by the ministers of the denomination. in all this there is nothing new. in every age conservatives and liberals have carried on their conflict over some form of this issue. what is new is the wide-spread character of the movement, the missionary enthusiasm which has been brought to it by its advocates and the consciousness on their part of interests tran- scending denominational lines and calling for a new alignment, with the fundamentalists of all denominations on one side and the liberals on the other. the presbyterian church—in the presbyterian church the controversy centred about the case of dr. harry emerson fosdick, a baptist clergyman who had been invited to act as stated supply for the first presbyterian church in new york city. dr. fosdick, who is also a professor in union theological seminary in that city and a man of modcrate liberal tendencies, made it his condition of accepting the call that he should be al- lowed to retain his membership in the baptist church. a sermon preached in may 1922, entitled “ shall the fundamentalists win?” was the occasion of an attack upon his theology by con- servative presbyterians, which led the general assembly of 1923 to direct the presbytery of new york to take such action as would require the preaching in the first presbyterian church to conform with the confession of faith. the presbytery, after full conference with dr. fosdick and the church, reported that such was now the case, whereupon the assembly of 1924, without passing any judgment on dr. fosdick’s theological views, ex- pressed the opinion that if he were to remain longer in the pulpit of the church, he should accept the standards of doctrine required of other ministers. on this issue dr. fosdick withdrew, declaring that “ creedal subscription to ancient confessions of faith is a practice dangerous to the welfare of the church and to the integrity of the individual conscience.” in connection with this controversy the general assembly in 1923 reasserted the so-called ‘“‘ five points,” a declaration orig- inally made in 1910, setting forth as essential doctrines of the christian faith, the virgin birth, the physical resurrection, the inerrancy of scripture, the substitutionary atonement and be- lief in the miracles. in reliance upon this statement the judicial commission of the assembly,in may 1925, declared that the fundamentalism and modernism presbytery of new york had erred in licensing a student who refused to affirm the virgin birth. the liberals attacked this procedure as an unconstitutional limitation of the liberty of interpretation accorded to every minister by the terms of sub- scription, and to the presbyteries by the historic precedents of the church. (cf. auburn affirmation of may 1924, signed by 1,283 members.) the baptist church.—in the baptist church the controversy has taken the form of an effort on the part of the conservatives to secure the adoption by the annual conference of a creed which should be used as a test of ministerial fellowship. this attempt failed at repeated conferences, but the conservatives, defeated at this point, have sought to secure their ends by instructions given to their board of home missions as to the conditions to be observed in the administration of their funds. one large bequest was actually accepted by the board on conditions which seemed to some of its critics unduly to limit its freedom. a parallel effort to secure control over the teaching of the seminaries has thus far failed of success. not the least important feature in the fundamentalist move- ment is its bearing upon foreign missions. in general the policy of the different missionary boards has been to put the respon- sibility for determining the doctrinal qualifications of candidates upon the home church; and in the work on the foreign field con- servatives and liberals have co-operated successfully in various union enterprises. fundamentalists have challenged this ar- rangement and attacked the theology of liberal missionaries. on the whole this attack has been unsuccessful, and the unity won on the field has thus far been maintained; but the battle is by no means over or the danger at an end. a case in point is the action of the general convention of the disciples at oklahoma city, okla., on oct. 6 1925, in reaffirming the principle of close communion which has been departed from by some of their missionaries in the interest of wider co-operation. the episcopal church.—in the episcopal church the con- troversy has centred about the literal observance of the creeds. on oct. § 1923 bishop lawrence of massachusetts made an address (afterwards published in pamphlet form) entitled fifty years, in which he pleaded for a liberal interpretation of the creeds. on nov. 14 1923 at dallas, tex., the bishops of the episcopal church met this challenge by issuing a pastoral in- sisting upon literal acceptance of the creeds and questioning the good faith of those ministers who gave their historic statements a symbolic interpretation. this pastoral was attacked by the liberals of the church who were organised in a body known as the modern churchman’s union. sermons were preached by leading liberals, like dr. leighton parks of st. bartholomew’s church of new york, and dr. william russell bowie of grace church of the same city, and manifestoes were issued by theologians like the volume of essays entitled creeds and loyalty by seven mem- bers of the faculty of the episcopal theological school of cambridge, mass. (1924). as a result of this agitation a trial for heresy begun against the rev. lee. w. heaton for denying the virgin birth was abandoned, and for the moment a truce has been declared. the bible institufes—one of the main sources of popular conservative propaganda is the so-called bible institutes, of which the most important are the moody bible institute in chicago and the bible institute of los angeles. these schools, interdenominational in character, recruiting their scholars from young people without college, and many of them without high school education, insist upon the inerrancy of the scripture, which they interpret commonly in the pre-millennarian sense. they are carrying on an extensive propaganda partly through periodicals of interdenominational character and partly through conventions (the so-called prophetic conferences), which bring together large numbers of people. while not primarily designed as theological seminaries, many of their pupils are finding their way into the churches and are reinforcing the conservative elements which are already there. it is against the background of these influences that one must interpret the tennessee trial. under the leadership of william fungus—futurism jennings bryan, the conservatives had been carrying on an active campaign throughout the country, attacking the views of liberal christians as fundamentally irreligious and unchristian and insisting not only upon rigid measures on the part of the individual churches, but also upon such a stiffening of the laws of the states as to prevent what they regard as the insidious propaganda of modernism in the schools. the storm-centre of the debate was the doctrine of evolution which, as interpreted by mr. bryan, involves a denial of the biblical doctrine of creation and thesurrender on the part of the teacher to an all- devouring materialism. in view of the fact that similar legislation has either been passed or attempted in other states, it is not likely that a final decision will be reached upon this larger issue until the u.s. supreme court has passed judgment upon the matter. (w. a. b.) fungus: see mycology. furnace: see electro-metallurgy. furness, horace howard (1833-1912), american shake- spearian scholar (sce 11.362c), died at wallingford, pa., aug. 13 1912. ilis variorum edition of cymbeline was ready for the printer and appeared in 1913.