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sandy soil and watered. A temperature of 70° to 75° Fahr. hastion of fuchsine is decolorized on the addition of sulphurous been found suitable for raising. The seedlings are pricked off acid, the casily soluble fuchsine sulphurous acid being formed. into shallow pots or pans, and when 3 in. in height are transferred | This solution is frequently used as a test reagent for the detection 10 3-in. pots, and are then treated the same as plants from of aldehydes, giving, in most cases, a red coloration on the cuttings. Fuchsias may be grafted as readily as camellias, addition of a small quantity of the aldehyde. preferably by the splice or whip method, the apex of a young The constitution of the suchsine bases (pararosaniline and rose shoot being employed as a scion; but the easiest and most usual aniline) was determined by E. and O. Fischer in 1878 (Ann., 1878, method of propagation is by cuttings. The most expeditious 194; p. 242); A. W. Hofmann having previously shown that oxi

dation of pure aniline alone or of pure toluidine yielded no fuchsine, way to procure these is to put plants in heat in January, and to whilst oxidation of a mixture of aniline and para-toluidine gave take their shoots when 3 in. in length. For summer flowering rise to the fine red dyestuff para-fuchsine (pararosaniline hydroin England they are best made about the end of August, and chloride) should be selected from the shortest-jointed young wood. They CH, C,H,NH4+2CH(NH4+3OHO-C(CH,NH4)2+2H,O. root readily in a compost of loam and silver-sand if kept close

Colour base (pararosaniline). and sprinkled for a short time. In from two to three weeks they


Pararosaniline hydrochloride, may be put into 3-in. pots containing a compost of equal parts of A. Rosenstiehl (Jahres., 1869, p. 693) found also that different rosrich loam, silver-sand and leaf-mould. They are subsequently anilines were obtained according to whether ortho- or para-toluidine moved from the frame or bed, first to a warm and shady, and

was oxidized with aniline, and he gave the name rosaniline to the then to a more airy part of the greenhouse. In January a little pararosaniline for the other, E. and O. Fischer showed that these

one obtained from aniline and ortho-toluidine, reserving the term artificial heat may be given, to be gradually increased as the compounds were derivatives of triphenylmethane and tolyldi. days lengthen. The side-shoots are generally pruned when they phenylmethane respectively. Pararosaniline was reduced to the have made three or four joints, and for bushy plants the leader is corresponding leuco

compound (paraleucaniline), from which by stopped soon after the first potting. Care is taken to keep the diazotization and boiling with alcohol, the parent hydrocarbon was plants as near the glass as possible, and shaded from bright (H2N-C.H.),C:CH:NH,CI»HC(CH.NH:-HČI). →HC(CH.N.Cl.) sunshine, also to provide them plentifully with water, except Pararosaniline hydrochloride. Paraleucaniline: at the time of shifting, when the roots should be tolerably dry,

→HC(CcHs). For the second potting a suitable soil is a mixture of well-rotted

Triphenylmethane. cow-dung or old hotbed mould with leaf-mould and sandy peat, The reverse series of operations was also carried out by the Fischers, and to promote drainage a little peat-moss may be placed teiphery Imethame being nitrated, and the nitro compound then immediately over the crocks in the lower part of the pot. Weak careful oxidation is converted into the dyestuff. A similar series of liquid manure greatly promotes the advance of the plants, and reactions was carried out with rosaniline, which was shown to be should be regularly supplied twice or thrice a week during the the corresponding derivative of tolyldiphenylmethane. flowering season. After this, water is gradually withheld from may be obtained by precipitating solutions of their salts with a

The free pararosaniline, C1H19N,0, and rosaniline, CH,N,0, them, and they may be placed in the open air to ripen their wood. caustic alkali, colourless precipitates being obtained, which crystal

Among the more hardy or half-hardy plants for inside borders lize from hot water in the form of needles or plates. The position are varieties of the Chilean species, F. macroslemma (or F. of the amino groups in pararosaniline was determined by the work magellanica), a shrub 6 to 12 ft. high with a scarlet calyx, such Fischer (Ber., 1880, 13, p. 2204) as follows: Nitrous acid converts

of H. Caro and C. Graebe (Ber., 1878, II, p. 1348) and of E. and 0. as F. m. globosa, F. m. gracilis; one of the most graceful and pararosaniline into aurin, which when superheated with water yields hardy of these, a hybrid F. riccarloni, was raised at Riccarton, para-dioxybenzophenone. As the hydroxyl groups in aurin correnear Edinburgh, in 1830. For inside culture may be mentioned spond to the amino gļoups in pararosaniline, two of these in the latter F. boliviana (Bolivia), 2 to 4 ft. high, with rich crimson flowers compound must be in the para position. The third is also in the

para position; for if benzaldehyde be condensed with aniline, with a trumpet-shaped tube; F. corymbiflora (Peru), 4 to 6 ft. condensation occurs in the para position, for the compound formed high, with scarlet flowers nearly 2 in. long in long terminal may be converted into para-dioxybenzophenone, clusters; F. fulgens (Mexico), 4 to 6 ft., with drooping apical C.H.CHO->CH;CH(CH.NH2): →CH:CH(C,H,OH), clusters of scarlet flowers; F. microphylla (Central America),

»CÓC,H,OH)3; with small leaves and small scarlet funnel-shaped flowers, the but if para-nitrobenzaldehyde be used in the above reaction and the petals deep red; F. procumbens (New Zealand), a pretty little then pararosaniline is the final product, and consequently the third

resulting nitro compound NO2.C.H.-CH(CH NH2), be reduced, creeper, the small flowers of which are succeeded by oval magenta- amino group occupies the para position. Many derivatives of para. crimson berries which remain on for months; and F. splendens rosaniline and rosaniline are known, in which the hydrogen atoms of (Mexico), 6 ft. high, with very showy scarlet and green flowers. the amino groups are replaced by alkyl groups; this has the effect But these cannot compare in beauty or freedom of blossom with

of producing a blue or violet shade, which becomes deeper as the

number of groups increases (see DYEING). the numerous varieties raised by gardeners. The nectar of fuchsia flowers has been shown to contain nearly 78% of cane FUCINO, LAGO DI (Lat. Lacus Fucinus), a lake bed of the sugar, the remainder being fruit sugar. The berries of some Abruzzi, Italy, in the province of Aquila, 2 m. E. of the town of fuchsias are subacid or sweet and edible. From certain species Avezzano. The lake was 37 m. in circumference and 65 ft. deep. a dye is obtainable. The so-called "native fuchsias" of southern From the lack of an outlet, the level of the lake was subject to and eastern Australia are plants of the genus Correa, natural great variations, often fraught with disastrous consequences. order Rutaceae.

As early as A.D. 52 the emperor Claudius, realizing a project of FUCHSINE, or MAGENTA, a red dyestuff consisting of a mixture Julius Caesar, constructed a tunnel 31 m. long, with 40 shafts at of the hydrochlorides or acetates of pararosaniline and rosaniline. intervals, by which the surplus waters found an outlet to the It was obtained in 1856 by J. Natanson (Ann., 1856, 98, p. 297) Liris (or Garigliano). No less than 30,000 workmen were emby the action of ethylene chloride on aniline, and by A. W. ployed for eleven years in driving this tunnel. In the following Hofmann in 1858 from aniline and carbon tetrachloride. It reign the tunnel was allowed to fall into disrepair, but was is prepared by oxidizing “aniline for red” (a mixture of aniline repaired by Trajan. When, however, it finally went out of use is and ortho-and para-toluidine) with arsenic acid (H. Medlock, uncertain. The various attempts made to reopen it from 1240 Dingler's Poly. Jour., 1860, 158, p. 146); by heating aniline onwards were unsuccessful. By 1852 the lake had gradually for red with nitrobenzene, concentrated hydrochloric acid and risen until it was 30 ft. above its original level, and had become a iron (Coupier, Ber., 1873, 6, p. 423); or by condensing formalde- source of danger to the surrounding countryside. A company hyde with aniline and ortho-toluidine and oxidizing the mixture.undertook to drain it on condition of becoming proprietors of th: It forms small crystals, showing a brilliant green reflex, and is site when dry; in 1854, however, the rights and privileges were soluble in water and alcohol with

formation of a deep red solution. purchased by Prince Giulio Torlonia (d. 1886), the great Roman It dyes silk, wool and leather direct, and cotton after mordanting banker, who carried on the work at his own expense until, in 1876, with tannin and tartar emetic (see DYEING). An aqueous solu- I the lake was finally drained at the cost of some £1,700,000. The

reclaimed area is 124 m. long, 7 m. broad, and is cultivated by be stated to be--carbon, 52 10 66; hydrogen, 4.7 to 7'4; oxygen, families from the Torlonia estates. The outlet by which it was 28 to 39; and nitrogen, 1.5 to 3% Average air-dried peat may drained is 4 m. long and 24 sq. yds. in section.

be taken as having a caloriớc value of 3000 to 3500 units, and when See A. Brisse and L. de Rotron, Le Desséchement du lac Pricin, dried at 100° C., and with a minimum of ash (4 to 5%), at about exécuté par S. E. le Prince A. Torlonia (Rome, 1876). (T. As.) 5200 units, or from a quarter to one-third more than that of an

FUEL (O. Fr. seuaile, popular Lat. focalia, from focus, hearth, equal weight of woodThe lighter and more spongy varieties of fire), a term applicable to all substances that can be usefully peat when air-dried are exceedingly inflammable, firing at a employed for the production of heat by combustion. Any temperature of 200° C.; the denser pulpy kinds ignite less readily element or combination of elements susceptible of oxidation may when in the natural state, and often require a still higher temperaunder appropriate conditions be made to burn; but only those ture when prepared by pulping and compression or partial that ignite at a moderate initial temperature and burn with com- carbonization. Most kinds burn with a red smoky flame, developparative rapidity, and, what is practically of more importance, ing a very strong odour, which, however, has its admirers in the are obtainable in quantity at moderate prices, can fairly be same way that wood smoke has. This arises from the destructive regarded as fuels. The clementary substances that can be so distillation of imperfectly carbonized organic matter. The ash, classed are primarily hydrogen, carbon and sulphur, while others like that of wood, is light and powdery, except when much sand finding more special applications are silicon, phosphorus, and the is present, when it is of a denser character. more readily oxidizable metals, such as iron, manganese, alu Peat is principally found in high latitudes, on exposed high minium and magnesium. More important, however, than the tablelands and treeless areas in more temperate climates, and elements are the carbohydrates or compounds of carbon, oxygen in the valleys of slow-llowing rivers, -as in Ireland, the west of and hydrogen, which form the bulk of the natural fuels, wood, Scotland, the tableland of Bavaria, the North German plain, peat and coal, as well as of their liquid and gaseous derivatives and parts of the valleys of the Somme, Oise and a few other coal-gas, coal-tar, pitch, oil, &c., which have high values as fuel. rivers in northern France. A principal objection to its use is its Carbon in the elementary form has its nearest representative in extreme bulk, which for equal evaporative effect is from 8 to 18 the carbonized fuels, charcoal from wood and coke from coal. times that of coal. Various methods have been proposed, and

adopted more or less successfully, for the purpose of increasing Solid Fuels.

the density of raw peat by compression, either with or without Wood may be considered as having the following average pulping; the latter process gives the heaviest products, but the composition when in the air-dried state: Carbon, 39.6; bydro- improvement is scarcely sufficient to compensate for the cost.

gen, 4.8; oxygen, 34:8; ash, 1.0; water, 20%. Lignite or brown coal is of intermediate character between Wood.

When it is freshly felled, the water may be from 18 to peat and coal proper. The best kinds are undistinguishable in 50%. Air-dried or even green wood ignites readily when a con- quality from free-burning coals, and the lowest earthy siderable surface is exposed to the kindling flame, but in large kinds are not equal to average peat. When freshly

Ligalte. masses with regular or smooth surfaces it is often difficult to get raised, the proportion of water may be from 45 to 50% and it to burn. When previously torrefied or scorched by heating to even more, which is reduced from 28 to 20% by exposure to a temperature of about 200°, at which incipient charring is set up, dry air. Most varieties, however, when fully dried, break up it is exceedingly inflammable. The ends of imperfectly charred into powder, which considerably diminishes their utility as fuel, boughs from the charcoal heaps in this condition are used in Paris as they cannot be consolidated by coking. Lignite dust may, and other large towns in France for kindling purposes, under the however, be compacted into serviceable blocks for burning, by name of fumerons. The inflammability, however, varies with pressure in machines similar to those used for brick-making, the density,--the so-called hard woods, oak, beech and maple, either in the wet state as raised from the mines or when kilntaking fire less readily than the softer, and, more especially, dried at 200°C. This method was adopted to a very large extent the coniferous varieties rich in resin. The calorific power of in Prussian Saxony. The calorific value varies between 3500 absolutely dry woods may as an average be taken at about 4000 and 5000 units, and the evaporative factor from 2•16 when freshly units, and when air-dried, i.e. containing 25% of water, at 2800 raised to 5.84 for the best kinds of lignite when perfectly dried. to 3000 units. Their evaporative values, i.e. the quantities of Of the other natural fuels, apart from coal (q.0.), the most water evaporated by unit weight, are 3.68 and 4.44.

important is so-called vegetable refuse, such as cotton stalks, Wood being essentially a faming fuel is admirably adapted for brushwood, straw, and the woody residue of sugar-cane use with heat-receiving surfaces of large extent, such as loco- after the extraction of the saccharine juice known as Other motive and marine boilers, and is also very clean in use. The megasse or cane trash. These are extersively used in absence of all cohesion in the cinders or unburnt carbonized countries where wood and coal are scarce, usually for residue causes a large amount of ignited particles to be projected providing steam in the manufactures where they arise, e.g. from the chimney, when a rapid draught is used, unless special straw for thrashing, cotton stalks for ploughing, irrigating, or spark-catchers of wire gauze or some analogous contrivance are working presses, and canc trash for boiling down sugar or driving used. When burnt in open fireplaces the volatile products given the cane mill. According to J. Head (Proc. Inst. of Civil Enoff in the apartment on the first heating have an acrid penetrat- gineers, vol. xlvüi. p. 75), the evaporative values of i lb of these ing odour, which is, however, very generally considered to be different articles when burnt in a tubular boiler are-coal, 8 Pb; agreeable. Owing to the large amount of water present, no very dry peat, 4 Ib; dry wood, 3.58- 3.52 Ib; cotton stalks or high temperatures can be obtained by the direct combustion of megasse, 3.2-2.7 Ib; straw, 2.46-2-30 lb. Owing to the wood, and to produce these for metallurgical purposes it is siliceous nature of the ash of sraw, it is desirable to have a necessary to convert it previously either into charcoal or into means of clearing the grate bars from slags and clinkers at short inflammable gas.

intervals, and to use a steam jet to clear the tubes from similar Peat includes a great number of substances of very unequal deposits. fuel value, the most recently formed spongy light brown kind The common fuel of India and Egypt is derived from the

approximating in composition to wood, while the dung of camels and oxen, moulded into thin cakes, and dried

dense pitchy brown compact substance, obtained from in the sun. It has a very low heating power, and in burning the bottom of bogs of ancient formation, may be compared with gives off acrid ammoniacal smoke and vapour. lignite or even in some instances with coal. Unlike wood, how Somewhat similar are the tan cakes made from spent tanners' ever, it contains incombustible matter in variable but large bark, which are used to some extent in eastern France and in quantity, from 5 to 15% or even more. Much of this, when the Germany. They are made by moulding the spent bark into cakes, amount is large, is often due to sand mechanically intermixed; which are then slowly dried by exposure to the air. Their effect when air-dried the proportion of water is from 8 to 20%. When is about equivalent to 80 and 30% of equal weights of wood and these constituents are deducted the average composition may coal respectively.

satural fuels,



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Sulphur, phosphorus and silicon, the other principal com- of a weighed quantity in the furnace of a boiler, and measuring the bustible elements, are only of limited application as fuels. The amount of water evaporated by the heat developed. first is used in the liquidation of sulphur-bearing rocks. The ore

In a research upon the heating power and other properties of coal

for naval use, carried out by the German admiralty, the results is piled into large heaps, which are ignited at the bottom, a tabulated below were obtained with coals form different localities. certain proportion, from one-fourth to one-third, of the sulphur

The heats of combustion of elements and compounds will be content being sacrificed, in order to raise the mass to a sufficient I found in most of the larger works on physical and chemical constants: temperature to allow the remainder to melt and run down to the collecting basin. Another applica

Slag left
Ashes in

Water eva

Soot in tion is in the so-called "pyritic smelting," where

in Grate. Ashpit. Flues.

porated by ores of copper (9.v.) containing iron pyrites, FeS2,

i lb of Coal are smelted with appropriate fluxes in a hot blast, Westphalian gas coals. 0.33-6-42 2.83– 6-53 0.32-0-46 6.60–7.45 lb without preliminary roasting, the sulphur and iron Do. bituminous coals

0.98-9.10 1.97- 9.63 0.24-0.88 7:30-8.66 of the pyrites giving sufficient heat by oxidation to Do. dry coals

1.93-5.70 4:37-10-63 0.24-0.48 7.03-8.51

Silesian coals liquefy both slag and metal. Phosphorus, which is

0.92-1.30 3.15- 3.50 0.24-0.30 6.73-7.10 Welsh steam coals

1.20-4.07 4.07 of value from its low igniting point, receives its only Newcastle coals


8-41 2.57


7.28 application in the manufacture of lucifer matches. The high temperature produced by burning phosphorus is in a convenient series is given in the Annuaire du Bureau des Longitudes, part due to the product of combustion (phosphoric acid) being appearing in alternate years. The following figures for the principal solid, and therefore there is less heat absorbed than would be the fuel elements are taken from the issue for 1908; they are expressed

in gramme

"calories" or heat units, signifying the weight of water case with a gaseous product. The same effect is observed in a

in grammes that can be raised 1°C. in temperature by the combustion still more striking manner with silicon, which in the only special of i gramme of the substance, when it is oxidized to the condition case of its application to the production of heat, namely, in the shown in the second column: Bessemer process of steel-making, gives rise to an enormous


Product of Combustion. Calories. increase of temperature in the metal, sufficient indeed to keep the iron melted. The absolute calorific value of silicon is lower


Water, H20, condensed to liquid 34.500 than that of carbon, but the product of combustion (silica)

as vapour i


Carbon being non-volatile at all furnace temperatures, the whole of

Carbon dioxide, CO,

7,868 the heat developed is available for heating the molten iron,


7.900 instead of a considerable part being consumed in the work of Amorphous

8,133 volatilization, as is the case with carbonic oxide, which burns Siliconto waste in the air.

Amorphous Silicon dioxide, SiO,

6,414 Crystallized

6,570 A ssay and Valuation of Carbonaceous Fuels. The utility or value

Phosphorus Phosphoric" pentoxide, P,0% 5,958 of a fuel depends upon two principal factors, namely, its calorific Sulphur

Sulphur dioxide, SO2, gaseous 2,165 power and its calorific intensity or pyrometric effect, that Caforific

is, the sensible temperature of the products of combustion. The results may also be expressed in terms of the atomic equivalent

The first of these is constant for any particular product of combustion independently of the method by which the burning is weight of the substance, 12 for carbon, 28 for silicon, &c.

of the combustible by multiplying the above values by the atomic effected, whether by oxygen, air or a reducible metallic oxide. It is most conveniently determined in the laboratory, by measuring the calorimeter is higher than that obtainable under working con

In all fuels containing hydrogen the calorific value as found by the heat evolved during the combustion of a given weight of the fuel. The method of Lewis Thompson is one of the most useful. The

ditions by an amount equal to the latent heat of volatilization of calorimeter consists of a copper cylinder in which a weighed quantity though under ordinary conditions of use the vapour passes away un

water which reappears as heat when the vapour is condensed, of coal intimately mixed with 10-12 parts of a mixture of 3 parts condensed. This gives rise to the distinction of higher and lower of potassium chlorate and 1 of potassium nitrate is deflagrated calorific values for such substances, the latter being those generally under a copper case like a diving-bell, placed at the bottom of a deep used in practice. The

differences for the more important compound glass jar filled with a known weight of water. The mixture is fired

gaseous fuels are as follows: by a fuse of lamp-cotton previously soaked in a nitre solution and

Calorific Value. dried. The gases produced by the combustion rising through the

Higher. Lower. water are cooled, with a corresponding increase of temperature in

Acetylene, C2H, the latter, so that the difference between the temperature observed

• 11,920 11,500 Ethylene, ci :


11,120 before and after the experiment measures the heat evolved. The

Methane, CHA

13,240 11,910 instrument is so constructed that 30 grains (2 grammes) of coal are

Carbon monoxide, co


2,440 burnt in 29,010 grains of water, or in the proportion of 1 to 937, these numbers being selected that the observed rise of temperature The calorific intensity or pyrometric effect of any particular fuel in Fahrenheit degrees corresponds to the required evaporative value depends upon so many variable elements that it cannot be deterin pounds, subject only to a correction for the amount of heat mined except by actual experiment. The older method

Calorific absorbed by the mass of the instrument, for which a special coefficient was to multiply the weight of the products of combustion

intensity is required and must be experimentally determined. The ordinary by their specific neats, but this gave untrustworthy bomb calorimeter is also used. An approximate method is based results as a rule, on account of two circumstances--the great increase upon the reduction of lead oxide by the carbon and hydrogen of the in specific heat at high temperatures in compound gases such as coal, the amount of lead reduced affording a measure of the oxygen water and carbon dioxide, and their instability when heated to expended, whence the heating power may be calculated, i part of 1800° or 2000°. At such temperatures dissociation to a notable pure carbon being capable of producing 341 times its weight of lead. extent takes place, especially with the latter substance, which is also The of eration is performed by mixing the weighed sample with a readily reduced to carbon monoxide when brought in contact with large excess of litharge in a crucible, and exposing it to a bright carbon at a red heat-a change which is attended with a large red heat for a short time. After cooling, the crucible is broken and heat absorption. This effect is higher with soft kinds of carbon, the reduced button of lead is cleaned and weighed. The results such as charcoal or soft coke, than with dense coke, gas retort obtained by this method are less accurate with coals containing carbon or graphite. These latter substances, therefore, are used much disposable hydrogen and iron pyrites than with those approxi- when an intense local heat is required, as for example, in the Deville mating to anthracite, as the heat equivalent of the hydrogen in furnace, to which air is supplied under pressure. Such a method is, excess of that required to form water with the oxygen of the coal however, only of very special application, the ordinary method being is calculated as carbon, while it is really about four times as great. to supply air to the fire in excess of that required to burn the fuel Sulphur in iron pyrites also acts as a reducing agent upon litharge, to prevent the reduction of the carbon dioxide. The volume of and increases the apparent effect in a similar manner.

flame, however, is increased by inert gas, and there is a proportionate The evaporative power of a coal by the bove methods, diminution of the heating effect. Under the most favourable conand also by calculating the separate calorific factors of the com- ditions, when the air employed has been previously raised to a high ponents as determined by the chemical analysis, is always consider-temperature and pressure, the highest attainable flame temperature ably above that obtained by actual combustion under a steam boiler, from carbonaceous fuel seems to be about 2100°-2300° C.; this is : as in the latter case numerous sources of loss, such as imperfect realized in the bright spots or eyes " of the tuyeres of blast furnaces. combustion of gases, loss of unburnt coal in cinders, &c., come into Very much higher temperatures may be reached when the products play, which cannot be allowed for in laboratory experiments. It is of combustion are not volatile, and the operation can be effected usual, therefore, to determine the value

of a coal by the combustion by using the fuel and oxidizing agent in the proportions cxactly


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required for perfect combustion and intimately mixed. These scientific possibility, and some attempts had been made to adopt
conditions are met in the " Thermit process of Goldschmidt, it in practice upon a commercial scale, but the insufficiency,
where finely divided aluminium is oxidized by the oxide of some
similar metal, such as iron, manganese or chromium, the reaction and still more the irregularity, of the supplies prevented it from
being started by a primer of magnesium and barium peroxide. coming into practical use to any important extent until about
The reaction is so rapidly effected that there is an enormous rise in 1898, when discoveries of oil specially adapted by chemical
temperature, estimated to be 5400°F. (3000 ° C.), which is sufficient
to melt the most refractory metals, such as chromium. The slag composition for fuel purposes changed the aspect of the situation,
consists of alumina which crystallizes in the forms of corundum and These discoveries of special oil were made first in Borneo and
ruby, and is utilized as an abrasive under the name of corubin. later in Texas, and experience in treating the oils from both

The chemical examination includes the determination of (!) localities has shown that while not less adapted to produce moisture, (2) ash, (3) coke, (4) volatile matter, (5) fixed carbon in kerosene or illuminating oil, they are better adapted to produce mined by noting the loss in weight when a sample is heated at 100° fuel oil than either the Russian or the Pennsylvanian products. for about one hour. The ash is determined by heating a sample Texas oil did not hold its place in the market for long, because in a muffle furnace until all the combustible matter has been burnt the influx of water into the wells lowered their yield, but disoff. The ash, which generally contains silica, oxides of the alkaline coveries of fuel oil in Mexico have come later and will help io earths, ferric oxide (which gives the ash a red colour), sulphur, &c. maintain the balance of the world's supply, although this is still of coke is very important on account of the conclusions concerning a mere fraction of the assured supply of coal

. the nature of the coal which it permits to be drawn. A sample is With regard to the chemical properties of petroleum, it is not finely powdered and placed in a covered porcelain crucible, which is surrounded by an outer one, the space between them being packed necessary to say more in the present place than that the lighter with small coke. The crucibles are heated in a wind furnace for and more volatile constituents, known commercially as naphtha I to it hours, then allowed to cool, the

inner crucible removed, and benzene, must be removed by distillation in order to leave and the coke weighed. The coke may be (1) pulverulent,, (2) a residue composed principally of hydrocarbons which, while cokes indicate a non-caking bituminous coal, rich in oxygen if the containing the necessary carbon for combustion, shall be suffiamount be below 60%, but if the amount be very much less it ciently free from volatile qualities to avoid premature ignition generally indicates a lignite; if the amount be above 80% it indi: j and consequent danger of explosion. Attempts have been made cates an anthracite containing little oxygen or hydrogen. A fritted to use crude oil for fuel purposes, and these have had some coke indicates a slightly coking coal, while the spongy appearance success in the neighbourhood of the oil wells and under boilers points to a highly coking coal which has been partly fused in the

A compact coke is yielded by good coking coals, and is of unusually good ventilation both as regards their chimneys usually large in amount. The volatile matters are determined as the and the surroundings of their stokeholds; but for reasons both loss of weight on coking less the amount of moisture. The fixed of commerce and of safety it is not desirable to use crude oil carbon" is the carbon retained in the coke, which contains in addition where some distillation is possible. The more complete the the ash already determined. The fixed carbon is therefore the difference between the coke and the ash, and may be determined from process of distillation, and the consequent removal of the volatile these figures; or it may be determined directly by burning off the constituents, the higher the flash-point, and the more turgid coke in a muffle and noting the loss in weight. Sulphur may be and viscous is the fuel resulting; and if the process is carried to present as (1) organic sulphur, (2) as iron pyrites or other sulphides, an extreme, the residue or fuel becomes difficult to ignite by the the amount is generally so small that only the total sulphur is ordinary process of spraying or atomizing mechanically at the determined. . This is effected by heating a mixture of the fuel moment immediately preceding combustion. The proportions with lime and sodium carbonate in a porcelain dish to redness in a which have been found to work efficiently in practice are as muffle until all the carbonaceous matter has been burnt off. The

follows: residue, which contains the sulphur as calcium sulphate, is trans


88.00 ferred to a beaker containing water to which a little bromine has been added. Hydrochloric acid is carefully added, the liquid


10-75 % filtered and the residue washed. To the filtrate ammonia is added,


1.25 % and then barium chloride, which precipitates the sulphur as barium

Total sulphate. Sulphur existing in the form of sulphates may be removed by washing a sample with boiling water and determining the sulphuric

The standards of safety for liquid fuel as determined by acid in the solution. The washed sample is then fused in the usual way to determine the proportion of sulphur existing as iron pyrites. flash-point are not yet finally settled, and are changing from time The distinction between sulphur present as sulphate and sulphide to time. The British admiralty require a flash-point

of 270° F., is of importance in the examination of coals intended for iron and to this high standard, and the consequent viscosity of the smelting, as the sulphates of the earthy metals are reduced by the fuel used by vessels in the British fleet, may partly be attributed metallic sulphides in the ash acts prejudicially upon the metal. them. The German admiralty have fixed a flash-point of 187°F., affecting the quality of the iron produced, while the sulphur of the the low rate of combustion that was at first found possible in produced in the combustion are noxious and have very corrosive same time with much higher measure of evaporative duty than Coals for gas-making should contain little sulphur, as the gases and have used oil of this standard with perfect safety, and at the properties. Chlorine is rarely determined, but when present in has been attained in British war-vessels. In the British merquently chlorine-bearing coals cannot be used. The element is cantile marine Lloyd's Register has permitted fuel with a flashdetermined by fusing with soda lime in a muffle, dissolving the residue point as low as 150° F. as a minimum, and no harm has resulted. in water and precipitating with silver nitrate. Phosphorus is The British Board of Trade, the department of the government potassium carbonates, extracting the residue with hydrochloric

acid, which controls the safety of passenger vessels, has fixed a higher and twice evaporating to dryness with the same acid. The residue standard upon the basis of a minimum of 185°. In the case of is dissolved in hydrochloric acid, a few drops of serric chloride added, locomotives the flash-point as a standard of safety is of less and then ammonia in excess. The precipitate of serric phosphate importance than in the case of stationary or marine boilers, is then treated as in the ordinary estimation of phosphates. Il it be because the storage is more open, and the ventilation, both of the a fuel, the dried sample is treated with copper oxide as in the ordinary storage tanks and the boilers during.combustion, much more estimation of these elements in organic compounds. (H. B.) persect than in any other class of steam-boilers. Liquid Fuel.

The process of refining by distillation is also necessary to

reduce two impurities which greatly retard storage and comVegetable oil is not used for fuel except for laboratory pur- bustion, i.c. water and sulphur. Water is found in all crude poses, partly because its constituent parts are less adaptable petroleum as it issues from the wells, and sulphur exists in for combustion under the conditions necessary for steam-raising, important quantities in oil from the Texas wells. Its removal but chiefly because of the commercial difficulty of producing it was at first found very expensive, but there no longer exists with sufficient economy to compete with mineral fuel either solid difficulty in this respect, and large quantities of petroleum fuel or liquid.

practically free from sulphur are now regularly exported from The use of petroleum as fuel had long been recognized as a | Texas to New York and to Europe.

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Water mixed with fuel is in intimate mechanical relation, and has since amalgamated with the Royal Dutch Petroleum Com. frequently so remains in considerable quantities even after the pany controlling the extensive wells in Dutch Borneo, and process of distillation. It is in fact so thoroughly mixed as to together they supply large quantities of liquid fuel for use in the form an emulsion. The effect of feeding such a mixture into a Far East. In the United States of America liquid fuel is not furnace is extremely injurious, because the water must be decom-only used for practically the whole of the manufacturing and posed chemically into its constituents, hydrogen and oxygen, locomotive purposes of the state of Texas, but factories in New thus absorbing a large quantity of heat which would otherwise York, and a still larger number in California, are now discarding be utilized for evaporation. Water also directly delays com the use of coal and adopting petroleum, because it is more bustion by producing from the jet a long, dull, red flame instead economical in its consumption and also more easily handled in of a short bright, white flame, and the process of combustion, transit, and saves nearly all the labour of stoking. So far the which should take place by vaporization of the oil near the supplies for China and Japan bave been exported from Borneo, furnace mouth, is postponed and transferred to the upper part of but the discoveries of new oil-fields in California, of a character the combustion-box, the tubes, and even the base of the chimney, specially adapted for fuel, have encouraged the belief that it may producing loss of heat and injury to the boiler structure. The be possible to supply Chile and Peru and other South American most effective means of ridding the fuel of this dangerous countries, where coal is extremely expensive, with Californian impurity is by heat and settlement. The coefficients of expansion fuel; and it has also found its way across the Pacisic to Japan of water and oil by heat are substantially different, and a There are believed to be large deposits in West Africa, but in the moderate rise of temperature therefore separates the particles meantime the only sources of supply to those parts of Africa and precipitates the water, which is easily drawn off-leaving where manufacture is progressing, i.e. South Africa and Egypt, the oil available for use. The heating and precipitation are are the oil-fields of Borneo and Texas, from which the import usually performed upon a patented system of settling tanks has well begun, from Texas to Alexandria via the Mediterranean, and heating apparatus known as the Flannery-Boyd system, and from Borneo to Cape Town via Singapore. which has proved itself indispensable for the successful use at In England, notwithstanding the fact that there exist the sea of petroleum fuel containing any large proportion of water. finest coal-fields in the world, there has been a surprising develop

The laboratory and mechanical use of petroleum for fuel has ment of the use of petroleum as fuel. The Great Eastern railway already been referred to, but it was not until the year 1870 that adapted 120 locomotive engines to its use, and these ran with

petroleum was applied upon a wider and commercial regularity and success both on express passenger and goods Progress

scale. In the course of distillation of Russian crude trains until the increase in price due to short supply compelled foel.

petroleum for the production of kerosene or lamp oil, a return to coal fuel. The London, Brighton & South Coast

large quantities of refuse were produced-known by railway also began the adaptation of some of their locomotive the Russian name of aslalki—and these were found an incụm engines, but discontinued the use of liquid fuel from the same brance and useless for any commercial purpose. To a Russian cause. Several large firms of contractors and cement manu. oil-refiner gifted with mechanical instinct and the genius for facturers, chiefly on the banks of the Thames, made the same invention occurred the idea of utilizing the waste product as adaptations which proved mechanically successful, but were fuel by spraying or atomizing it with steam, so that, the thick not continued when the price of liquid fuel increased with the and sluggish fluid being broken up into particles, the air increased demand, necessary for combustion could have free access to it. The The chief factors of cconomy are the greater calorific value earliest apparatus for this purpose was a simple piece of gas-tube, into which the thick oil was fed; by another connexion steam at high pressure was ad. mitted to an inner and smaller tube, and, the end of the tube nearest to the furnace being open, the pressure of the steam blew the oil into the furnace, and by its velocity broke

KO; it up into spray. The apparatus worked with success from the first. Experience pointed out the proper proportionate sizes for the inlets of steam and oil, the proper pressure for the steam, and the proportionate sizes for the orifices of admission to the fur

Fig. 1.-Holden Burner naces, as well as the sizes of air-openings and best arrangements of fire-bricks in the furnaces of oil than coal (about 16 lb of water per fb of oil fuel evaporated themselves, and what had been a waste product now became from a temperature of 212° F.), not only in laboratory practice, a by-product of great value Practically all the steam power but in actual use on a large scale, and the saving of labour both in South Russia, both for factories and navigation of the inland in transit from the source of supply to the place of use and in seas and rivers, is now raised from astalki fuel

the act of stoking the furnaces. The use of crancs, In the Far East, including Burma and parts of China and hand labour with shovels, wagons and locomotives,

Economy Japan, the use of liquid fuel spread rapidly during the years horses and carts, is unavoidable for the transit of fuel

of liquid 1899, 1900 and 1901, owing entirely to the development of the coal; and labour to trim the coal, to stoke it when Borneo oil-fields by the enterprise of Sir Marcus Samuel and the under combustion, and to handle the residual ashes, are all large British corporation known as the Shell Transport and indispensable to steam-raising by coal. On the other hand, a Trading Company, of which he is the head. This corporation system of pipes and pumps, and a limited quantity of skilled

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