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    "source_title": "Encyclopaedia Britannica (1926)",
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    "chunk_id": "1926:boilers:b4448f91c4f5",
    "title": "BOILERS",
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    "verified_text": "-the principal developments and im- provements in boiler design, construction and operation since i9to may be summarised as larger units, additional application of heat-saving devices, increasing pressures, powdered coal hring and greatly improved automatic stokers, combustion con- trol systems, deconcentrators, de-aerators and the experimental use of alloy steels in forged, cast and welded material. size of units——in 1910 the largest units in one setting were the stirling boilers at the delray station at detroit, mich., with 24,000 sq. ft. of surface. many boilers of this general design are now in use in sizes varying from 13,000 sq. ft. to 30,000 square fect. most of these installations are in the north-central united states. flanagan (proc. iron and steel elec. eng.) claims that the design is particularly advantageous where the feed water is bad. the delauney-belleville co. in france has installed a number of similar boilers under the ladd patents, while in america this type is best represented by the ford plant, river rouge, michigan. the horizontal tube type has increased in size from 7,000 sq. ft. in 1910, best represented by the 14 tubes high, 21 tubes wide, tube bank, with three 42 in. drums of the babcock & wilcox co., to sizes containing 14,000 to 24,000 sq. ft. of heating sur- face, 24 tubes high, 54 tubes wide,with but one 60 in. cross-drum. maximum furnace widths of 13 ft. in roto have been increased to 30 ft. in 1925, while the tube length—which was standard in 1910 as 18 ft.—has been increased in some instances to 24 fect. steel-cased air-tight settings, the general use of superheaters and economisers, and greatly increased furnace volumes, the reap- —boilers pearance of air prehcaters in stationary practice and the in- creasing use of water-tube sectional designs are notable develop- ments. european practice.-—in europe, boilers of the garbe type have been increasingly popular, although the stirling, babcock & wilcox, yarrow, spearing, steinmuller and other types have made progress. the largest sizes have been of stirling type, although the double babcock & wilcox boilers at barton, manchester, are nearly as large. uel consumption.—perhaps the best indicator of progress 1s the amount of coal burned per front foot of furnace. in 1910 this did not exceed 4oo lb. per hour when good efficiency was_b- tained. this figure has been increased until 1,400 4b. per front foot has been burned in regular work at good efficiency with 1,700 to 1,900 lb. per hour during peak pericds at reduced effi- ciency. the modern large boiler with 30 ft. furnace will burn 20 tons of coal per hour at better than 70% cefliciency, evaporat- ing 200 tons of water per hour from and at 212° fahrenheit. steam pressures.—maximum steam temperatures still remain at about 750° f., although oil stills are being worked at 1,000° f. to 1,100° fahrenhcit. steam pressures have steadily risen from 200 ib. gauge to 600 ib. for the majority of the in- stallations completed in 1925, while one large boiler of 1,200 ib. pres- sure is in service at weymouth, mass., and several smaller ones in germany and sweden. the swedish installa- {ions are of the blom- quist type, where the boiler consists of ro-in. tubes revolving in the furnace with the water held to their inside sur- face by centrifugal force (see fig. 2). most of the german boilers are of the schmidt type. superheaters—t h e use of superheaters has become general, and most of the newer in- stallations are using maximum temperatures around 7oo° f., which was true of only a few plants in r910. radiant heat superheaters of a number of types are in use but have not become standard. steel tube economisers have nearly replaced the cast-iron tube variety for high pressure work. many designs of both tubular and plate air heaters are also in use, but this apparatus has not been in use long enough to be standardised. electric boilers~—where there is a surplus of hydroelectric power, the electric boiler, first manufactured by sulzer bros., has been largely used. the greatest use of this boiler is in canada, where it has been brought to a high degree of perfec- tion. the hydroelectric power must be very cheap or else coal or other fuel excessively dear, to make the use of these boilers economical. the internal combustion boiler, where the fuel is burned inside of the boiler in contact with the water, has been used for some years in chemical works, for gas turbines, and in torpedo service. little real work has been done, and commer- cially the last two types may be neglected. construction.—most of the rules for boiler construction before 1q1o were drawn {from the rules of such classification societies as lloyd’s, bureau veritas, a.b.c. or from such associations as the manchester steam users’ assn. or the swiss boilermakers’ and i | ica! | nt vill i aly. 7 an fic. e256 electric steam gener- ator—three phase—single unit system. boilers users’ association. in 1915, the american society of mechan- ical engineers bringing together the designers, manufacturers, insurance socicties and users, adopted the report of the boiler code committee. this code is now standard in the united states, having been adopted by 19 states and 15 cities. most of the german states have similar construction laws, and the tendency toward a uniform construction law is well marked. tubes.—both iron and steel boiler tubes are in use, but by far the most extensively used are the hot finished and scamless bg) \\ re i ames nn rs ae. ~ iss sy a le on pi = \\y vv nz = n \\ \\) qv fic. 2.—blomquist high pressure boiler, 1,500 ib. per square inch. cold-drawn steck tubes made from pierced billets. sectional headers are made from cast steel, from welded forged stecl, and swaged up from seamless drawn steel tubes. boiler drums are made from plates riveted in the usual way, but welded shells are in use as well as seamless forged shells. alloy steels have been introduced for all purposes and are finding a place in high- pressure work, the drum for the 1,200-lb. weymouth boiler being a hollow forging with swaged ends 24 in. jn internal diam- eter and 4 in. thick. staybolt manufacture has been greatly 1m- proved, and the control of riveting pressures in order to secure perfect filling of the hole without overworking the metal has been studied with great advantage. operating practice.—in general, the improvement of practice has been the securing of greatly increased capacity while main- taining a better efficiency. this was not possible with hand firing or with the short and inefficient stokers in vogue in 1910. the longer underfeed stokers put in at conner’s creek, detroit, in 1912, gave that station a maintained boiler efficiency over a year of 78%, which was excellent work. efficiencics over a year of 88% for boiler, superheater and economiscr are now reported from lakeside (milwaukee) and other stations. the forced draft chain grate stoker has becn most successfully used, and is built in very large sizes, while the underfced type has been much lengthened and improved. capacities.—capacities have been greatly increased. the evaporation of 4 to 6 lb. of water per sq. ft. of surface was con- sidered good practice in 1910, and a maintained efficiency of 78% at this rating was difficult. evaporations of ro to 12 ib. at the same efficiency are now possible, and some late guarantces will run as high as 17 lb. equivalent evaporation per sq. ft. of surface at an efficiency of over 90%. these improvements are due to better stoker design, to better utilisation of radiant heat, to the use of pure feed water and to automatic combustion control. ash grinders, properly located, allow practically all of the combustible to be burned out of the aoi fuel and most of the sensible heat of the ash to be absorbed by the air for combustion. soot blowers, installed in most new installations since tg1o, enable tubes to be kept clean. de- acrators for eliminating oxygen and other gases from the feed water prevent corrosion and assist in keeping the surfaces clean. much more care is taken with the feed water, and watcr-softening plants are in universal use. deconcentrators, working con- tinuously, take water from the circulation system, filter it and return clean water to the boiler. automatic combustion control systems, where the air and coal are automatically proportioned to the load, help in securing perfect combustion and maintaining a high efficiency. furnace design has progressed until a 30 ft. by 20 [t. setting with walls 40 ft. high is possible. greatly im- proved refractories are obtainable and the air-cooled firebrick furnaces gave little trouble. water-cooled furnace walls of the fin type, cast-steel box or refractory types, are in successful use, the water used being part of the circulatory system of the boiler. powdered coal.—the most striking departure, however, is the expansion of powdered coal firing, which has extended the range of good efficiency and enabled the operator to use different qualities of coal in the same apparatus with equal efliciency. the systems lends itself to the maintenance of high combustion tem- peratures and high cos, and the losses of combustible in ash and clinker are much less than where a fire bed is used. the cost of pulverising the fuel is not large, and many of the later instal- . coal <——\" bunker (i > a oe van i] wy supe. - ly, burners in wl eo. oo furnace | € i f nh | via aha i rns yj. i, | sss 2d? fic. 3.—section through boiler house, trenton channel, mich., showing great height of settings. stirling boiler. lations have adopted this method of firing. the system neccssi- tates large furnace volumes, about one cu. ft. of space being re- quired for each 1-5 lb. of coal for best efficiency. the bin and feeder system, with a central pulverising plant is most successful at present, but the many unit systems are promising and much used for small installations. oil firing.—since 1910, the mechanical atomising of oil fuel has been introduced with marked success, as much as 3,000 lb. of oil per hour being handled by a single burner. when the oil is heated to the right viscosity (that is, between 3°-4° engler) 402 atomisation is nearly molecular and the results are good. the power and heat used is usually less than -5°% of the steam output of the boiler in contrast to -75% to 1°5% consumed when steam atomisation is used. see f. j. drover, oil and oil- fired boilers, 1924. (g. a. o.) boito, arrigo (1842-1918), italian composer (sce 4.155), died june 10 1918. bok, edward william (1863- ), american editor and author, was born at helder, iiolland, oct. 9 1863, and brought to the united states when six years old. educated in the brooklyn public schools, he became an office boy with the western union telegraph company. continuing his education at a night school, he entered the employ of henry holt & co., publishers, in 1882, and two years later became associated with charles scribner’s sons, publishers, eventually becoming ad- vertising manager. ile acted as editor of the brooklyn afagasine from 1882 to 1884. in 1886 he founded the bok syndicate press, the success of which led to the offer of the editorship of the ladies’ home journal in 1889; under his management this magazine became one of the most successful publications in america. after 30 years as editor he retired in rato. a year later he published the americanization of edivard bok, which won the year’s award of the joseph pulitzer prize for the best biography, and the gold medal of the academy of political and social science. in 1923 he created the american peace award, providing $100,000 for the best practicable plan by which the united states might co-operate with other nations to achieve and preserve the peace of the world, one half to be paid upon the acceptance of the plan by a selected jury and the balance upon its acceptance by the senate. the plan submitted by dr. c. a. livermore, of the new york peace society, won the award. in addition to his autobiography mr. rok published, among other works: successward (1895), the young amfanin business (1900), ler brother's letters (anonymous, 1906), wha j believe in poverty (1915), two persons (1922), a man from afaine (1923), taice thirty (1925), dollars oniy (1926), you; a personal message (1926) and america, give afe a chance (1926). bokhara or bukhara (see 4.156), a province of the uzbek socialist soviet republic (see turkestan). bolivia (see 4.166), a republic in south america and a mem- ber of the league of nations. estimates of the area vary, the boundary dispute with paraguay being still unsettled. the of- ficial estimate is 708,195 square miles. no exact census of the population has been taken. in 1925 it was estimated at 2,820,- 119, but it is probable that, allowing for aboriginal tribes, bolivia has about 3,200,000 inhabitants. i. political history on aug. 6 1909 president montes was succeeded by senor ehodoro villaz6n. from this moment the progress of bolivia was most marked, and during the period to the end of 1925 con- ditions in the republic were much more stable, both economi- cally and politically, than ever before. general montes assumed office for a second term on aug. 6 1913, and remained president until 1917. the world war had a considerable influence upon the trade of bolivia: imports decreased, while her exports, mainly minerals, increased very considerably in value. the country proclaimed its neutrality in 1914, but departed from this attitude in consequence of germany’s submarine policy. diplomatic relations with germany were severed on april 13 1917, the reason for this action being that a german submarine had torpedoed in neutral waters a ship with the bolivian minister to berlin on board. the republic took no direct part in the war on the side of the allies, but all her resources in metals were at their disposal. montes relinquished office on aug. 6 1917, and was succeeded by his former minister of finance, sefior jose gutierrez guerra. shortly after this the agitation for an outlet to the pacific reached an acute stage. the policy of president guerra was apparently aimed at a rapprochement with chile over the long-standing grievance resulting from the loss of bolivia’s coastal territories. popular indignation against this attitude led to demonstrations: guerra was forced to resign, and was escorted out of the country botto—bolivia to arica. meanwhile the world war had ended. bolivia was represented at the versailles conference, and signed the peace treaty of 1919. as a signatory of the treaty, she became an original member of the league of nations. relations with chile—following the deposition in july 1920 of president guerra, the provisional govt. of bolivia prosecuted the popular demand for a revision of the situation in regard to her lost territory. invoking article 19 of the covenant of the league of nations, the bolivian delegates to the first assembly of the league presented a request on nov. 1 1920 for the modification of the treaty of 1904, whereby hostilities with chile, nominally maintained since the termination of the war of 1879, were formally concluded. it was contended that the treaty had been imposed on bolivia by force; that chile had not ful- filled certain of its clauses; and that the resulting situation con- stituted a constant menace to peace: while bolivia suffered a wrong, contrary to the rights of nations, because, under the pact she had ‘‘ become a country completely enclosed and de- prived of access to the sea.”’ the assembly of the league decided that it could not properly entertain this request for the alteration of a treaty, and that ordinarily an international compact could only be modified by the contracting parties. bolivia then attempted to become a party to the negotiations between chile and peru for the settle- ment of the controversy over the disputed territory of tacna- arica. chile declined to admit bolivia’s claim to participation in the negotiations, declaring that it had accepted the invitation of the united states to a conference at washington to consider the unfulfilled clauses of the treaty of ancon, and that those clauses related only to chile and peru. saatvedra’s presidency.—in view of chile’s refusal to recognise bolivia in the tacna-arica negotiations, president bautista saavedra, who had been elected president in 1920 and had en- tered office on jan. 29 1921, appealed early in 1922 to president harding of the united states, explaining bolivia’s case and urg- ing that she be admitted as a third party at the approaching conference. dr. saavedra emphasised that the negotiations affected bolivia as a victim of the war in which she had been associated with peru against chile, and that the question of the disputed territory could not be adjusted unless his nation’s loss of an outlet to the sea were repaired. further he argued that bolivia’s consent to the treaty of 1904, by which she recognised chile’s sovereignty over the epartment of atacama, was ob- tained under duress. in his reply president harding took the view that he could not ask bolivia to be a party to the negotia- tions: the inclusion of bolivia in the discussions, he stated, was a matter for the sole consideration of chile and peru. thus bolivia was excluded from the conferences at washington, which resulted in an agreement by chile and peru to submit their dispute over the unfulfilled clauses of the treaty of ancon to the arbitration of the president of the united states. the presidency of dr. saavedra was productive of a greater efficiency in administration, and in marked economic progress. nevertheless some measure of political unrest was experienced both in 1924 and 1925. a revolutionary movement took place in july 1924 and was promptly suppressed by the government. ostensibly the object was to promote the secession of the province of santa cruz to the neighbouring republic of brazil, but active opposition to the policy of the saavedra govt. was really the purpose of the disturbance. in jan. 1925 dr. jose c. villanueva, a physician who had been serving as minister of public instruction and agriculture, and abdon saavedra, a brother of the president, were nominated as republican candi- dates for president and vice-president. the liberal party nomi- nated dr. salamanca for the presidency. after a vigorous electoral campaign the republican candidates were elected on may 2 by an overwhelming majority. the successful candidate for the presidency should have taken office on aug. 6, but con- gress refused io ratify his election on the ground that it was invalid because dr. villanueva had not resigned public office, as required by the constitution, at least six months before election. meanwhile saavedra continued in office. bolivia at this moment the centenary of bolivian independence was being celebrated by an international exposition at la paz, and a good deal of political excitement developed. on sept. 1, con- gress formally declared the election of may 2 null and void. president saavedra transferred his office to dr. felipe guzman, president of the senate, to administer the government provi- sionally, pending a new election. a cabinet was appointed to deal with the political unrest resulting from the unseating of dr. villanueva. to some extent the army was affected, and on sept. 18 martial law was proclaimed in three provinces. dr. villanueva and his partizans were accused of tampering with the army and the unseated president was instructed to leave the country. conditions then improved. in dec. the new election was held and dr. hernando siles, a republican, was elected. he was installed in office in jan. 1926. the constitution adopted in 1880 was still in force in 1926. sucre remained officially the capital of the republic, but actu- ally la paz had become the political and commercial capital. the national congress meets in la paz every year; the presi- dential palace and most of the government offices are main- tained there, and sucre is merely the seat of the supreme court. (cw. s. ro.) ii. financial and economic history finance —the annual revenue of the republic rose from 12,583,232 bolivianos (bs.) in roro to bs. 43,063,489 in 1924: expenditure increased in proportion, the figure for 1924 being bs. 41,494,049. surpluses of bs. 816,667 and bs. 1,368,540 were realised in 1918 and 1924 respectively, but in the 10 years 1915- 24 the net deficits amounted to bs. 39,512,416. on jan. 1 1925 the national debt amounted to bs. 127,834,844: it consisted of external debt, bs. 92,970,000, internal debt, bs. 20,647,355 and floating debt, bs. 14,217,489. under a contract with the equi- table trust co. of new york, dated may 31 1922, bolivia ar- ranged for a loan of $33,000,000 at 8% with a currency of 25 years, of which sum $29,000,000 had been issued in 1925, part being used to redcem a french loan for railway construction, and the balance for further railway and road building. production and indusiry—mineral deposits remained the principal source of wealth in bolivia during the period 1910-25. throughout the world war intense activity prevailed in mining owing to the increased demand at high prices for such metals as tin, lead, copper and wolfram. in 1925 bolivia stood second among countries in the world in the production of tin. of her total exports in 1924, valued at bs. 115,191,500, metals were represented by tin, bs. 84,200,000; lead, bs. 9,080,000; silver, bs. 8,800,000; coppcr, bs. 4,587,000; bismuth, bs. 2,387,000; antimony, bs. 410,000, and zinc, bs. 86,000. the exploitation of the vast mineral wealth of the country depends largely upon the development of transport facilities and the utilisation of the immense water-power resources of the country. there has been a distinct advance in agricultural production, but methods were still primitive in 1925 and only a comparatively small area was systematically cultivated. rubber production particularly is proving a valuable industry, exports in 1924 being valued at bs. 2,930,000. stock-raising was still in a backward condition in 1925, but to this branch of industry and to agriculture the government is giving serious attention. trade.—developments in mineral production resulted in a great increase in exports. the balance of trade between to10 and 1925 was consistently in favour of bolivia, particularly dur- ing the war years when the prices of metals rose to phenomenal heights. the course of trade is shown by the iollowing table:— | imports | i-xports | bs. ds. 1910\" -< : . : : 48,502,394 | 75,622,146 eot36 3 or. oes he 4 54,762,833 | 93,721,513 1918 34,999,886 182,612,850 1923 | 62,914,009 | 107,693,000 62,570,000 115,191,500 the countries furnishing the largest amounts of imports were 403 the united states, chile, great britain and argentina. in 1924 the main items of imports, and their values, were: manufactures, bs. 40,057,864; foodstuffs, etc., bs. 15,833,005; raw materials, bs. 5,640,248; live animals, bs. 1,028,345. exports to the united kingdom were valued at bs. 81,909,611; to the united states, bs. 25,521,144; to argentina, bs. 3,228,041; and to chile, bs. 463,119. communications.—as a country without a seaboard bolivia is dependent on railways passing through the territories of her neigh- bours for her communication with the outer world. trafhe rights over these railways are guaranteed by treaties. there are three distinct connections with the pacific coast. one outlet is by way of the la paz-guaqui railway, thence by the southern railway through peru to the port of mollendo. further south bolivia can be reached from the chilean port of arica by a railway that runs prac- tically straight through to la paz, the distance between the two places being only 279 m., as against the journey of 529 m. between mollendo and la paz. still further south there is the railway from antofagasta, in chile, which joins the main bolivian trunk line at uyuni. a great improvement in the communications with bolivia was the completion in 1925 of the section of the trunk line between atocha and tupiza, thus giving the republic through connection, by way of la quiaca, with buenos aires and the atlantic seaboard. on the east the country can be reached via the amazon and madeira rivers, most of the rubber and other tropical produce of the beni and colonias regions is shipped this way, with the mamore-madeira railway acting as a link with the river communications. in 1925 bolivia had about 1,300 m. of railways. a further 200 m. were under construction, while projects were being considered for about 1,000 miles. in association with colonisation schemes it was proposed also to create ports along the paraguay river—constituting part of the eastern frontier of bolivia—so that steamers could approach the republic by way of the river plate. money and banking.—by a law of dec. 31 1908 bolivia virtually adapted the gold standard. the monetary unit is the silver boliviano, given a value under the above law of bs. 12-50 to english and peruvian pounds, both of which are legal tender. in 1920 united states gold coins were also declared legal tender, the boliviano having a par value to the dollar of $0-3893. after 1914 practically all the silver coins were exported from bolivia, and in 1925 the currency con- sisted of nickel coins and paper money. on dec. 31 1924 the stock of gold held by the three principal banks of the country amounted to bs. 21,067,855 against a total note circulation on the same date of bs. 34,754,848. during the war period the exchange value of the boliviano fluctuated considerably. efforts were made by the govern- ment to steady the exchange by means of a moratorium, the pro- hibition of gold exports, the suspension of banking conversion and the fixing of an official rate of exchange, but none of these expedi- encics sulficed to maintain the boliviano at par. a national law of jan. 7 1911 gave bolivia a semi-state bank known as the banco de la nacion boliviano. its original capital was ls. 15,937,500, of which half was subscribed by the government from proceeds of a loan raised in paris. this bank absorbed the banco de bolivia y londres, the banco agricola and the banco industrial. all national banks operating in bolivia must subscribe 20 °;, of their capital to the banco de la nacien, though foreign banks may place this quota in national bonds. the paid-up capital of the banco de la nacien on dec. 3t 1924 was bs. 22,000,000, and the republic then held 114,738 of the total otf 176,000 shares. a german bank, the banco aleman transatlantico, is the only foreign institu- tion in bolivia, though banking operations are also conducted through special departments of several large foreign mercantile con- eerns. there are two nationally constituted mortgage banks, the credito hipotecario de bolivia and the banco hipotecario nacional. in nov. 1914 a law was passed confining the right to issue paper currency to the banco de la nacien, though permitting till dec. 31 1924 the circulation of notes to the approximate value of bs. 3,000,000 already issued by the banco nacional and the banco mercantil. all such notes were required to be cancelled by the end of 1929. il. education and defence education.—after 1910 substantial progress was made in educa- tion, and the degree of illiteracy greatly reduced. it stood as high as 84° in 1900, but was reduced to about 60%, in 1925. this was due not only to the big increase in the number of schools, but to the education of the army conscripts from the remote districts, who help to impart a knowledge of reading and writing to indians who previ- ously did not know spanish. the amount spent on education in bolivia rose from bs. 1,497,643 in rgto to ds. 3,650,203 in 1924. schools are maintained either by the national govt. or by the municipalities. the number of national schools rose from 187 in iy10 to 450 in 1918, and in 1925 was well over 500. the attendance at these schools was 58,766 in 1918, and in 1925 was estimated to be over 80,000. in addition to the elementary schools, there are the high schools, or colegios nacionales, as well as private academies. the supply of teachers is met by training colleges established throughout the country, with a superior normal institute in la paz, a remark- 404 able impetus has been given of recent years to practical or vocational training. schools of arts and crafts are now found in the principal cities, and an institute of applied arts at la paz has an enrolment of about 250 trainees. the university of la paz furnishes instruc- tion in law, medicine, obstetrics, pharmacy, dentistry and theology. each department in the republic also has its own university, with the exception of beni, but in these institutions only one course, that of law, is generally given. a national school of mines exists at oruro, and the government also maintains a school of agriculture and animal husbandry, a school of commerce, an institute of bacteriology, an allied school of agronomy and veterinary science, a conservatory of music and various model farms. defence.—universal military service is theorctically the basis of bolivia’s defence system, all males between the ages of 19 and 50 being liable. actually only a limited number of the available con- scripts are taken into the army, lots being drawn to fill the annual quota for training. a law of dec. 15 1915 provided for a permanent force of 3,577 men, and the ordinary peace strength of the army is about that number, with an immediate reserve of 15,000 men, though in 1925 there were also available for defence about 200,000 men who had undergone some training. there are four regiments of infantry, a regiment of cavalry, a regiment of field artillery, equipped with schneider-creusot guns, a regiment of mountain artillery and a machine gun corps of 150 men. the amount actually spent on defence during 1924 was bs. 7,878,170. bibliography.—the peru-bolivia boundary comntission report (1916); anuario nacional estadistico y geogrefico de bolivia (1919); w. l. shurz, bolivia—a commercial and industrial itandbook, pub- lished by the u.s. department of commerce (1921); c. h. prodgers, adventures in bolivia (1922); a. v. l. guise, six years in bolivia (1922); lionel portman, three asses in bolivia (1922); memoria presentado ai congreso por el ministre de comercio y fomento (1924): ministerio de relaciones exteriores, official itandbook to bolivia (1924); guta nactonal de mineria (1925); bolivia 1825~1925 (1925); memoria presentada al congreso por ei ministerio de ilacienda e industria (1925); la reptblica (centennial aaa (1925). la boll weevil, cotton.—the first home of the cotton boll weevil was undoubtedly in the plateau region of mexico or central america. before 1892 the insect had spread throughout the larger portion of mexico. it occurs southward to guatemala and costa rica, and in the eastern half of cuba. about 1892 it crossed the rio grande near brownsville, tex., and entered u.s. territory. it may have flown across, or it is possible that it was carried over in seed cotton. by 1894 it had spread to halia dozen counties in southern texas. since 1894 it has extended its range annually from 40 to 160 m., although in several instances the winter conditions have caused a decrease in the areas that are infested. at the end of the year 1922, 87°% of the american cotton belt had become infested by the weevil. this infested area produces most of the cotton crop of the united states, comprising almost all of the important cotton-producing sections. prac- tically the only territory remaining uninfested is the semi-arid zone along the western margin of the cotton belt. some of this territory has been invaded in seasons of favourable weather, but the weevils have been driven back in periods of adverse weather. whether the weevil will ever become seriously injurious in that territory is problematical, but it has shown marked ability to adapt itself to unfavourable conditions. the losses caused by the boll weevil are both direct and indirect and extend throughout practically the entire cotton belt. the bureau of crop esti- mates of the u.s. dept. of agriculture reported the potential production of cotton prevented by weevils in the year ro21 as 6,277,000 bales. the adult boll weevil is about one-fourth of an inch long, varying from one-eighth to one-third of an inch, with a breadth about one- third of its length. this measurement includes the snout, which is approximately half the length of the body. variation in size is due to the amount of food the insect has obtained in the larva stage. {individuals from bolls (unripe pods containing lint and seed) are therefore nearly always larger than those from squares (fruit buds). the recently emerged individuals are light yellowish in colour, but this changes to a grey or nearly black shade in a few weeks’ time. in the field the most conspicuous indication of the presence of the boll weevil is the flaring and falling of numbers of squares or buds. unfavourable climatic conditions and careless cultivation, however, frequently cause great shedding of the fruit, which is often mistaken for weevil damage. if excessive shedding be noted and the squares upon being cut open show a white, curved grub that has fed upon the contents, there is little doubt that the boll weevil is the insect causing the damage. boll weevil—bolton the bol) weevil passes the winter as an adult or beetle. with the advent of autumn weather the adult boll weevils in cotton fields begin to seek protection against the winter. they fly from the ficlds in every direction, although their movements are governed partially by the prevailing winds. they may fly into hedges, woods, cornfields, haystacks, farm buildings or other places. a number of weevils also obtain hibernating quarters without leaving the cotton fields. these may crawl into cracks in the ground, under grass, weeds or other trash, and into the burrs from which the cotton has been picked. during the winter the weevils take no food, and remain practically dormant; on warm days they may move about to a cer- tain extent. emergence from hibernation depends primarily upon temperature and rainfall in the spring, although some minor factors are concerned. in the southern portions of the cotton belt emergence usually begins from the first to the middle of march, but farther north it is somewhat later. emergence from hibernation has been prolonged from the middfe of march to june 28, and in more extreme cases from the middle of feb. to about the first of july. in the spring and throughout the fruiting season of cotton the eggs are deposited by the female weevils in cavities formed by eating into the fruit of the plant. an egg hatches under normal conditions in about 3 days, and the grub immediately begins to feed. in from 7 to 12 days the larva or grub passes into its pupal stage, correspond- ing to the cocoon of butterflies and moths. this stage lasts from 3 to 5 days. then the adult issues, and in about 5 days begins to breed. climatic conditions cause considerable variation in the dura- tion of the stages, but on an average it requires from 2 to 3 weeks for the weevil to develop from the egg to the adult. the males feed upon the squares and bolls without moving until the food begins to de- teriorate. the females refrain, throughout most of the season, from depositing eggs in squares visited by other females, but late in the autumn, when all of the fruit has become infested, several eggs may be placed in a single square or boll. as many as 15 larvae have been found in a boll. the squares are greatly preferred as food and as places for depositing eggs. as long as a large supply of squares is present the bolls are not generally damaged to any serious extent. the bolls, therefore, have a fair chance to develop as long as squares are being formed. the weevil, so far as at present known, breeds in no plants other than cotton and a wild plant related to cotton and found in the mountains of arizona. in spite of the many complexities involved in the problem of weevil control, efficient methods (see corton) have been developed for reducing its damage, which are of practical use to growers, these are described in farmers’ bulletin no. 1329, procurable on request from the u.s. dept. of agriculture, washington, d.c. (s. r. c.) bolshevism is the name given, first to the theories and later to the practice of a section of the russian social democrats. since 1917, when the bolsheviks came into ‘power in russia, the word has become currently accepted as synonymous with communism. the russian social democrat party was formed under the tsarist regime to work for the replacement of the state structure by a dictatorship of the organised proletariat according to the theories of marx. at its second convention in london (1903) the committee of this party divided into the bolsheviks (meaning majority) with 26 members and the mensheviks (= minority) with 25. after 1910 the two groups no longer sat in one committee; and in 1912 the bolsheviks, under lenin, deposed the old central committee at the conference of prague, declaring ““ we are the party.” the bolsheviks, as opposed to the mensheviks, aimed at the immediate establishment of the soviet system, rejecting an inter- mediate form of democracy. all power was to be concentrated in the hands of one centralised bureaucracy, a professional rev- olutionary class which required blind obedience from the mass of the proletariat, ignoring all other classes of society completely. the mensheviks demanded a democratic republic, in which the proletariat should co-operate with the peasants and the intelli- gentsia. in the abortive revolution of 1905 revolutionary workers’ councils first made their appearance in the factories and achieved a certain amount of success. the revolutionary activity of the bolsheviks was maintained unremittingly up to and during the world war. discontent was sedulously sown in the army and the factories, and the method of penetration by communist ‘“‘ cells”? was widely adopted. the tsarist govt. fell in ro17; after a short interregnum of the kerensky regime, the bolsheviks seized the supreme power and built up a new form of government based on the soviet or councilsystem.(see communism; russia.) bolton (sce 4.180) had a population of 180,851 in ro11, ‘and of 178,678 in 1921. in 1923 it was estimated at 182,200. the bom bay—-bombs area of the parish and municipal borough is 15,279 ac. of land, and 371 of water. leverhulme park, 98} ac., the gift of the ist lord leverhulme, was opened in 1919, and the white bank estate of 27 ac., with a house which is used as a central school, was presented by the descendants of john haslam in 1920. the churches of st. barnabas and st. margaret, halliwell, were con- secrated in 1913, and the parish of st. chad was formed out of several others in 1912. a presbyterian church and the clare- mont baptist institute were erected in 19ro. minerva hall, the headquarters of the lancashire and cheshire miners’ federa- tion, was opened in 19r4 in bridgeman street. bombay, india (see 4.183b), population (1921) 1,175,914, has undergone considerable development recently owing to the activities of the development directorate appointed in 1920. large schemes were put in hand, destined eventually to house 250,000 of the poorer inhabitants, and so relieve the existent overcrowding, and to add 2 sq. m. to the area of the city by reclamation of land in back bay and east colaba. the cost seriously exceeded the estimates, on account of the unsuitable nature of the material dredged, and it was proposed in 1926 to complete only a part of the reclamation and to dispose of the dredging plant. south salsette island, between bombay and the mainland, is being developed, industrial and residential colonies have been established outside the city, and several new arterial thoroughfares opened. the mahim scheme is complete, and comprises two main ave- nues and cross roads, with a road 60 ft. wide from worli. the reclamation scheme between mazagon and sewri is also finished, and the cotton, grain and oil depets have been moved from co- laba. previously raw cotton was carried on carts from the goods yards to the cotton green at colaba, but now the bombay port trust has provided railway communication between the railway station, the docks and the depdt at sewri, which has sheds to hold 3,000,000 bales of cotton. in 1921 the bank of bombay united with those of bengal and madras, forming the imperial bank of india, with local head- quarters in bombay. a new general post office has been built near the victoria station, the old one being now used for the fort area only, and in igt1, the foundation stone was laid of buildings for the royal institute of science on mayo and fs- planade roads, containing a library, public hall, examination rooms, etc. a pasteur institute, where research in tropical medi- cine is carried on and plague vaccine prepared, has been estab- lished in old government house, and a large sanitary institute was opened in princess street in 1915. harbour improvements.—in the harbour a deep water pier has been built at trombay for discharge of bulk petrol, with a pipe connection to sewrl, and the seawall of the alexandra dock is extended for 1,500 ft. to form the new ballard pier, with a pas- senger station where passengers embark and disembark. a floating caisson for merewether dry dock was ordered in july 1924, and the harbour defences have been remodelled and sup- plied with the heaviest guns. docks are to be built on a large area of reclaimed land to the north of the present docks. other recent activities of the bombay port trust include the building of a line to connect with the great indian peninsula and bom- bay, baroda and central railways at a point 6 m. from the city, to take over traffic and convey it direct to the docks and depets as required. part was opened in 1915, and the main system finished in 1924. the total length with sidings is over 100 miles. electric power.—the remarkable electric power works of the tata hydroelectric scheme were opened in 1915. the monsoon rainfall on the ghats is impounded in three lakes at lonavla, and falls to a general station where 40,000 h.p. is generated by five turbines; more power will be available as the scheme devel- ops. it is conveyed 42 m. to a receiving station on bombay island by aerial transmission cables, whence it is distributed to mills and other customers. further hydroelectric developments are in progress near the present lakes where the andhra river has been dammed to form a lake 12 m. long. the company, con- nected with the tata supply company, was formed in 1916, and the supply of power began in 1922, 405 a memorial of the landing of the king and queen in dec. 1911 has been erected on the apollo bunder, replacing the temporary pavilion erected for the occasion. previously the apollo bunder was used for embarking and disembarking passengers in fine weather with an iron shelter only. the memorial building of indian design is of yellow basalt, and consists of three halls. the large centre one is flanked by arched entrances, and the smaller ones seat 600 people in each. | trade commerce.—bombay suffered to a smaller extent than any other indian port from the world war, though shipping was seriously affected by mines; 1920-1 was a record year, for though there were prolonged strikes in 1919 and in jan. 1924, there was a strike in the mills which eventually affected 150,000 hands owing to the non-payment of a yearly bonus during a period of depression. there were disorders, and attempts, which were frustrated by the police, were made to burn down mills. there was much distress among the strikers, who returned to work in march, but in sept. 1925 trouble again arose. in that month only five mills were at work. bombay remains the chief distributing centre in western india for imported cotton goods, and there are 82 cotton spinning and weaving mills in the city and environs. the preponderating share of trade is in indian hands,and most of the mills have indian managers. in 1922-3 the total imports and exports were worth {217,017,000 (exports £93,572,000; imports £123,445,000), as compared with £142,394,c00 in 1912-3. (o. j. r. h.) bombay, university of.—in 1913 a start was made with the provision of lectures for post-graduate students in history, economics, philosophy, sanskrit and persian. in 1919, schools of sociology and economics were established for research, and buildings costing over 8 lakhs of rupees completed in 1923. the university is still mainly concerned with examinations and has affiliated to it a number of institutions in ahmadabad, baroda, bombay, dharwar, junagarh, karachi, poona, sangh and surat. ten lakhs of rupees have been given by sir cunimbhoy ebrahim for scholarships by way of repayable advances to mahommedan students going to other countries for higher studies.",
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