FIG. 6.--BURTON-UNION SYSTEM OF CLEANSIN_Encyclopaedia Britannica, 11th Edition, "Bréquigny, Louis Georges Oudard Feudrix de" to "Bulgaria" Volume 4, Part 3

The green beer is filled into the casks, and the excess of yeast, &c., then

works out through the swan necks into the long common gutter shown.]

[v.04 p.0513]

The presence of different types of phosphates in malt, and the important

influence which, according to their nature, they exercise in the brewing

process by way of the enzymes affected by them, have been made the subject

of research mainly by Fernbach and A. Hubert, and by P.E. Petit and G.

Labourasse. The number of enzymes which are now known to take part in the

brewing process is very large. They may with utility be grouped as

follows:--

Name. Rôle or Nature.

+- Cytase Dissolves cell walls of

| of starch granules.

In the malt ----+- Diastase A Liquefies starch

or mash-tun. +- Diastase B Saccharifies starch.

+- Proteolytic Enzymes -+- (1) Peptic.

| +- (2) Pancreatic.

+- Catalase Splits peroxides.

In fermenting +- Invertase Inverts cane sugar.

wort and -----+- Glucase Splits maltose into glucose.

yeast. +- Zymase Splits sugar into alcohol

and carbonic acid.

BIBLIOGRAPHY.--W.J. Sykes, _Principles and Practice of Brewing_ (London,

1897); Moritz and Morris, _A Text-book of the Science of Brewing_ (London,

1891); H.E. Wright, _A Handy Book for Brewers_ (London, 1897); Frank

Thatcher, _Brewing and Malting_ (London, 1898); Julian L. Baker, _The

Brewing Industry_ (London, 1905); E.J. Lintner, _Grundriss der

Bierbrauerei_ (Berlin, 1904); J.E. Thausing, _Die Theorie und Praxis der

Malzbereitung und Bierfabrikation_ (Leipzig, 1898); E. Michel, _Lehrbuch

der Bierbrauerei_ (Augsburg, 1900); E. Prior, _Chemie u. Physiologie des

Malzes und des Bieres_ (Leipzig, 1896). Technical journals: _The Journal of

the Institute of Brewing_ (London); _The Brewing Trade Review_ (London);

_The Brewers' Journal_ (London); _The Brewers' Journal_ (New York);

_Wochenschrift für Brauerei_ (Berlin); _Zeitschrift für das gesammte

Brauwesen_ (Munich).

(P. S.)

[1] They were classified at 28 lb in 1896, but since 1897 the standard has

been at the rate of 32 lb to the bushel.

[2] Inclusive of rice and maize.

[3] Exclusive of rice and maize.

[4] As a rule there is no separate "collecting vessel," duty being assessed

in the fermenting vessels.

BREWSTER, SIR DAVID (1781-1868), Scottish natural philosopher, was born on

the 11th of December 1781 at Jedburgh, where his father, a teacher of high

reputation, was rector of the grammar school. At the early age of twelve he

was sent to the university of Edinburgh, being intended for the clerical

profession. Even before this, however, he had shown a strong inclination

for natural science, and this had been fostered by his intimacy with a

"self-taught philosopher, astronomer and mathematician," as Sir Walter

Scott called him, of great local fame--James Veitch of Inchbonny, who was

particularly skilful in making telescopes. Though he duly finished his

theological course and was licensed to preach, Brewster's preference for

other pursuits prevented him from engaging in the active duties of his

profession. In 1799 he was induced by his fellow-student, Henry Brougham,

to study the diffraction of light. The results of his investigations were

communicated from time to time in papers to the _Philosophical

Transactions_ of London and other scientific journals, and were admirably

and impartially summarized by James D. Forbes in his preliminary

dissertation to the eighth edition of the _Encyclopaedia Britannica_. The

fact that other philosophers, notably Etienne Louis Malus and Augustin

Fresnel, were pursuing the same investigations contemporaneously in France

does not invalidate Brewster's claim to independent discovery, even though

in one or two cases the priority must be assigned to others.

The most important subjects of his inquiries are enumerated by Forbes under

the following five heads:--(1) The laws of polarization by reflection and

refraction, and other quantitative laws of phenomena; (2) The discovery of

the polarizing structure induced by heat and pressure; (3) The discovery of

crystals with two axes of double refraction, and many of the laws of their

phenomena, including the connexion of optical structure and crystalline

forms; (4) The laws of metallic reflection; (5) Experiments on the

absorption of light. In this line of investigation the prime importance

belongs to the discovery (1) of the connexion between the refractive index

and the polarizing angle, (2) of biaxial crystals, and (3) of the

production of double refraction by irregular heating. These discoveries

were promptly recognized. So early as the year 1807 the degree of LL.D. was

conferred upon Brewster by Marischal College, Aberdeen; in 1815 he was made

a member of the Royal Society of London, and received the Copley medal; in

1818 he received the Rumford medal of the society; and in 1816 the French

Institute awarded him one-half of the prize of three thousand francs for

the two most important discoveries in physical science made in Europe

during the two preceding years. Among the non-scientific public his fame

was spread more effectually by his rediscovery about 1815 of the

kaleidoscope, for which there was a great demand in both England and

America. An instrument of higher interest, the stereoscope, which, though

of much later date (1849-1850), may be mentioned here, since along with the

kaleidoscope it did more than anything else to popularize his name, was

not, as has often been asserted, the invention of Brewster. Sir Charles

Wheatstone discovered its principle and applied it as early as 1838 to the

construction of a cumbrous but effective instrument, in which the binocular

pictures were made to combine by means of mirrors. To Brewster is due the

merit of suggesting the use of lenses for the purpose of uniting the

dissimilar pictures; and accordingly the lenticular stereoscope may fairly

be said to be his invention. A much more valuable practical result of

Brewster's optical researches was the improvement of the British lighthouse

system. It is true that the dioptric apparatus was perfected independently

by Fresnel, who had also the satisfaction of being the first to put it into

operation. But it is indisputable that Brewster was earlier in the field

than Fresnel; that he described the dioptric apparatus in 1812; that he

pressed its adoption on those in authority at least as early as 1820, two

years before Fresnel suggested it; and that it was finally introduced into

British lighthouses mainly by his persistent efforts.

Brewster's own discoveries, important though they were, were not his only,

perhaps not even his chief, service to science. He began literary work in

1799 as a regular contributor to the _Edinburgh Magazine_, of which he

acted as editor at the age of twenty. In 1807 he undertook the editorship

of the newly projected _Edinburgh Encyclopaedia_, of which the first part

appeared in 1808, and the last not until 1830. The work was strongest in

the scientific department, and many of its most valuable articles were from

the pen of the editor. At a later period he was one of the leading

contributors to the _Encyclopaedia Britannica_ (seventh and eighth

editions), the articles on Electricity, Hydrodynamics, Magnetism,

Microscope, Optics, Stereoscope, Voltaic Electricity, &c., being from his

pen. In 1819 Brewster undertook further editorial work by establishing, in

conjunction with Robert Jameson (1774-1854), the _Edinburgh Philosophical

Journal_, which took the place of the _Edinburgh Magazine_. The first ten

volumes (1819-1824) were published under the joint editorship of Brewster

and Jameson, the remaining four volumes (1825-1826) being edited by Jameson

alone. After parting company with Jameson, Brewster started the _Edinburgh

Journal of Science_ in 1824, sixteen volumes of which appeared under his

editorship during the years 1824-1832, with very many articles from his own

pen. To the transactions of various learned societies he contributed from

first to last between three and four hundred papers, and few of his

contemporaries wrote so much for the various reviews. In the _North British

Review_ alone seventy-five articles of his appeared. A list of his larger

separate works will be found below. Special mention, however, must be made

of the most important of them all--his biography of Sir Isaac Newton. In

1831 he published a short popular account of the philosopher's life in

Murray's _Family Library_; but it was not until 1855 that he was able to

issue the much fuller _Memoirs of the Life, Writings and Discoveries of Sir

Isaac Newton_, a work which embodied the results of more than twenty years'

patient investigation of original manuscripts and all other available

sources.

Brewster's relations as editor brought him into frequent communication with

the most eminent scientific men, and he was naturally among the first to

recognize the benefit that would accrue from regular intercourse among

workers in the field of science. In an article in the _Quarterly Review_ he

threw out a suggestion for "an association of our nobility, clergy, gentry

and philosophers," which was taken up by others and found speedy

realization in the British Association for the Advancement of [v.04 p.0514]

Science. Its first meeting was held at York in 1831; and Brewster, along

with Charles Babbage and Sir John F. W. Herschel, had the chief part in

shaping its constitution. In the same year in which the British Association

held its first meeting, Brewster received the honour of knighthood and the

decoration of the Guelphic order of Hanover. In 1838 he was appointed

principal of the united colleges of St Salvator and St Leonard, St Andrews.

In 1849 he acted as president of the British Association and was elected

one of the eight foreign associates of the Institute of France in

succession to J.J. Berzelius; and ten years later he accepted the office of

principal of the university of Edinburgh, the duties of which he discharged

until within a few months of his death, which took place at Allerly,

Melrose, on the 10th of February 1868.

In estimating Brewster's place among scientific discoverers the chief thing

to be borne in mind is that the bent of his genius was not

characteristically mathematical. His method was empirical, and the laws

which he established were generally the result of repeated experiment. To

the ultimate explanation of the phenomena with which he dealt he

contributed nothing, and it is noteworthy in this connexion that if he did

not maintain to the end of his life the corpuscular theory he never

explicitly adopted the undulatory theory of light. Few will be inclined to

dispute the verdict of Forbes:--"His scientific glory is different in kind

from that of Young and Fresnel; but the discoverer of the law of

polarization of biaxial crystals, of optical mineralogy, and of double

refraction by compression, will always occupy a foremost rank in the

intellectual history of the age." In addition to the various works of

Brewster already noticed, the following may be mentioned:--Notes and

Introduction to Carlyle's translation of Legendre's _Elements of Geometry_

(1824); _Treatise on Optics_ (1831); _Letters on Natural Magic,_ addressed

to Sir Walter Scott (1831); _The Martyrs of Science, or the Lives of

Galileo, Tycho Brahe, and Kepler_ (1841); _More Worlds than One_ (1854).

See _The Home Life of Sir David Brewster,_ by his daughter Mrs Gordon.

BREWSTER, WILLIAM (c. 1566-1644), American colonist, one of the leaders of

the "Pilgrims," was born at Scrooby, in Nottinghamshire, England, about

1566. After studying for a short time at Cambridge, he was from 1584 to

1587 in the service of William Davison (? 1541-1608), who in 1585 went to

the Low Countries to negotiate an alliance with the states-general and in

1586 became assistant to Walsingham, Queen Elizabeth's secretary of state.

Upon the disgrace of Davison, Brewster removed to Scrooby, where from 1590

until September 1607 he held the position of "Post," or postmaster

responsible for the relays of horses on the post road, having previously,

for a short time, assisted his father in that office. About 1602 his

neighbours began to assemble for worship at his home, the Scrooby manor

house, and in 1606 he joined them in organizing the Separatist church of

Scrooby. After an unsuccessful attempt in 1607 (for which he was imprisoned

for a short time), he, with other Separatists, removed to Holland in 1608

to obtain greater freedom of worship. At Leiden in 1609 he was chosen

ruling elder of the Congregation. In Holland he supported himself first by

teaching English and afterwards in 1616-1619, as the partner of one Thomas

Brewer, by secretly printing, for sale in England, books proscribed by the

English government, thus, says Bradford, having "imploymente inough." In

1619 their types were seized and Brewer was arrested by the authorities of

the university of Leiden, acting on the instance of the British ambassador,

Sir Dudley Carleton. Brewster, however, escaped, and in the same year, with

Robert Cushman (c. 1580-1625), obtained in London, on behalf of his

associates, a land patent from the Virginia Company. In 1620 he emigrated

to America on the "Mayflower," and was one of the founders of the Plymouth

Colony. Here besides continuing until his death to act as ruling elder, he

was also--regularly until the arrival of the first pastor, Ralph Smith (d.

1661), in 1629 and irregularly afterward--a "teacher," preaching "both

powerfully and profitably to ye great contentment of ye hearers and their

comfortable edification." By many he is regarded as pre-eminently the

leader of the "Pilgrims." He died, probably on the 10th of April 1644.

See Ashbel Steele's _Chief of the Pilgrims; or the Life and Time of William

Brewster_ (Philadelphia, 1857); and a sketch in William Bradford's _History

of the Plimouth Plantation_ (new ed., Boston, 1898).

BRÉZÉ the name of a noble Angevin family, the most famous member of which

was PIERRE DE BRÉZÉ (c. 1410-1465), one of the trusted soldiers and

statesmen of Charles VII. He had made his name as a soldier in the English

wars when in 1433 he joined with Yolande, queen of Sicily, the constable

Richmond and others, in chasing from power Charles VII.'s minister La

Trémoille. He was knighted by Charles of Anjou in 1434, and presently

entered the royal council. In 1437 he became seneschal of Anjou, and in

1440 of Poitou. During the Praguerie he rendered great service to the royal

cause against the dauphin Louis and the revolted nobles, a service which

was remembered against him after Louis's accession to the throne. He fought

against the English in Normandy in 1440-1441, and in Guienne in 1442. In

the next year he became chamberlain to Charles VII., and gained the chief

power in the state through the influence of Agnes Sorel, superseding his

early allies Richmond and Charles of Anjou. The six years (1444-1450) of

his ascendancy were the most prosperous period of the reign of Charles VII.

His most dangerous opponent was the dauphin Louis, who in 1448 brought

against him accusations which led to a formal trial resulting in a complete

exoneration of Brézé and his restoration to favour. He fought in Normandy

in 1450-1451, and became seneschal of the province after the death of Agnes

Sorel and the consequent decline of his influence at court. He made an

ineffective descent on the English coast at Sandwich in 1457, and was

preparing an expedition in favour of Margaret of Anjou when the accession

of Louis XI. brought him disgrace and a short imprisonment. In 1462,

however, his son Jacques married Louis's half-sister, Charlotte de Valois,

daughter of Agnes Sorel. In 1462 he accompanied Margaret to Scotland with a

force of 2000 men, and after the battle of Hexham he brought her back to

Flanders. On his return he was reappointed seneschal of Normandy, and fell

in the battle of Montlhéry on the 16th of July 1465. He was succeeded as

seneschal of Normandy by his eldest son Jacques de Brézé (c. 1440-1490),

count of Maulevrier; and by his grandson, husband of the famous Diane de

Poitiers, Louis de Brézé (d. 1531), whose tomb in Rouen cathedral,

attributed to Jean Goujon and Jean Cousin, is a splendid example of French

Renaissance work.

The lordship of Brézé passed eventually to Claire Clémence de Maillé,

princess of Condé, by whom it was sold to Thomas Dreux, who took the name

of Dreux Brézé, when it was erected into a marquisate. HENRI EVRARD,

marquis de Dreux-Brézé (1762-1829), succeeded his father as master of the

ceremonies to Louis XVI. in 1781. On the meeting of the states-general in

1789 it fell to him to regulate the questions of etiquette and precedence

between the three estates. That as the immediate representative of the

crown he should wound the susceptibilities of the deputies was perhaps

inevitable, but little attempt was made to adapt traditional etiquette to

changed circumstances. Brézé did not formally intimate to President Bailly

the proclamation of the royal séance until the 20th of June, when the

carpenters were about to enter the hall to prepare for the event, thus

provoking the session in the tennis court. After the royal séance Brézé was

sent to reiterate Louis's orders that the estates should meet separately,

when Mirabeau replied that the hall could not be cleared except by force.

After the fall of the Tuileries Brézé emigrated for a short time, but

though he returned to France he was spared during the Terror. At the

Restoration he was made a peer of France, and resumed his functions as

guardian of an antiquated ceremonial. He died on the 27th of January 1829,

when he was succeeded in the peerage and at court by his son Scipion

(1793-1845).

The best contemporary account of Pierre de Brézé is given in the

_Chroniques_ of the Burgundian chronicler, Georges Chastellain, who had

been his secretary. Chastellain addressed a _Déprécation_ to Louis XI. on

his behalf at the time of his disgrace.

[v.04 p.0515] BRIALMONT, HENRI ALEXIS (1821-1903), Belgian general and

military engineer, son of General Laurent Mathieu Brialmont (d. 1885), was

born at Venlo in Limburg on the 25th of May 1821. Educated at the Brussels

military school, he entered the army as sub-lieutenant of engineers in

1843, and became lieutenant in 1847. From 1847 to 1850 he was private

secretary to the war minister, General Baron Chazal. In 1855 he entered the

staff corps, became major in 1861, lieutenant-colonel 1864, colonel in 1868

and major-general 1874. In this rank he held at first the position of

director of fortifications in the Antwerp district (December 1874), and

nine months later he became inspector-general of fortifications and of the

corps of engineers. In 1877 he became lieutenant-general. His far-reaching

schemes for the fortification of the Belgian places met with no little

opposition, and Brialmont seems to have felt much disappointment in this;

at any rate he went in 1883 to Rumania to advise as to the fortification

works required for the defence of the country, and presided over the

elaboration of the scheme by which Bucharest was to be made a first-class

fortress. He was thereupon placed _en disponibilité_ in his own service, as

having undertaken the Bucharest works without the authorization of his

sovereign. This was due in part to the suggestion of Austria, which power

regarded the Bucharest works as a menace to herself. His services were,

however, too valuable to be lost, and on his return to Belgium in 1884 he

resumed his command of the Antwerp military district. He had, further,

while in eastern Europe, prepared at the request of the Hellenic

government, a scheme for the defence of Greece. He retired in 1886, but

continued to supervise the Rumanian defences. He died on the 21st of

September 1903.

In the first stage of his career as an engineer Brialmont's plans followed

with but slight modification the ideas of Vauban; and his original scheme

for fortifying Antwerp provided for both enceinte and forts being on a

bastioned trace. But in 1859, when the great entrenched camp at Antwerp was

finally taken in hand, he had already gone over to the school of polygonal

fortification and the ideas of Montalembert. About twenty years later

Brialmont's own types and plans began to stand out amidst the general

confusion of ideas on fortification which naturally resulted from the

introduction of long-range guns, and from the events of 1870-71. The

extreme detached forts of the Antwerp region and the fortifications on the

Meuse at Liége and Namur were constructed in accordance with Brialmont's

final principles, viz. the lavish use of armour to protect the artillery

inside the forts, the suppression of all artillery positions open to

overhead fire, and the multiplication of intermediate batteries (see

FORTIFICATION AND SIEGECRAFT). In his capacity of inspector-general

Brialmont drafted and carried out the whole scheme for the defences of

Belgium. He was an indefatigable writer, and produced, besides essays,

reviews and other papers in the journals, twenty-three important works and

forty-nine pamphlets. In 1850 he originated the _Journal de l'armée Belge_.

His most important publications were _La Fortification du temps présent_

(Brussels, 1885); _Influence du tir plongeant et des obus-torpilles sur la

fortification_ (Brussels, 1888); _Les Régions fortifiées_ (Brussels, 1890);

_La Défense des états et la fortification à la fin du XIX^e siècle_

(Brussels, 1895); _Progrès de la défense des états et de la fortification

permanente depuis Vauban_ (Brussels, 1898).

BRIAN (926-1014), king of Ireland, known as BRIAN BORU, BOROMA, or BOROIMHE

(from _boroma_, an Irish word for tribute), was a son of a certain Kennedy

or Cenneide (d. 951). He passed his youth in fighting against the Danes,

who were constantly ravaging Munster, the northern part of which district

was the home of Brian's tribe, and won much fame in these encounters. In

976 his brother, Mathgamhain or Mahon, who had become king of Thomond about

951 and afterwards king of Munster, was murdered; Brian avenged this deed,

became himself king of Munster in 978, and set out upon his career of

conquest. He forced the tribes of Munster and then those of Leinster to own

his sovereignty, defeated the Danes, who were established around Dublin, in

Wicklow, and marched into Dublin, and after several reverses compelled

Malachy (Maelsechlainn), the chief king of Ireland, who ruled in Meath, to

bow before him in 1002. Connaught was his next objective. Here and also in

Ulster he was successful, everywhere he received hostages and tribute, and

he was generally recognized as the _ardri_, or chief king of Ireland. After

a period of comparative quiet Brian was again at war with the Danes of

Dublin, and on the 23rd of April 1014 his forces gained a great victory

over them at Clontarf. After this battle, however, the old king was slain

in his tent, and was buried at Armagh. Brian has enjoyed a great and not

undeserved reputation. One of his charters is still preserved in Trinity

College, Dublin.

See E.A. D'Alton, _History of Ireland_, vol. i. (1903).

BRIANÇON, a strongly fortified town in the department of Hautes-Alpes in

S.E. France. It is built at a height of 4334 ft. on a plateau which

dominates the junction of the Durance with the Guisane. The town itself is

formed of very steep and narrow, though picturesque streets. As it lies at

the foot of the descent from the Mont Genèvre Pass, giving access to Turin,

a great number of fortifications have been constructed on the heights

around Briançon, especially towards the east. The Fort Janus is no less

than 4000 ft. above the town. The parish church, with its two towers, was

built 1703-1726, and occupies a very conspicuous position. The Pont

d'Asfeld, E. of the town, was built in 1734, and forms an arch of 131 ft.

span, thrown at a height of 184 ft. across the Durance. The modern town

extends in the plain at the S.W. foot of the plateau on which the old town

is built and forms the suburb of Ste Catherine, with the railway station,

and an important silk-weaving factory. Briançon is 51½ m. by rail from Gap.

The commune had a civil population in 1906 of 4883 (urban population 3130),

while the permanent garrison was 2641--in all 7524 inhabitants.

Briançon was the _Brigantium_ of the Romans and formed part of the kingdom

of King Cottius. About 1040 it came into the hands of the counts of Albon

(later dauphins of the Viennois) and thenceforth shared the fate of the

Dauphiné. The Briançonnais included not merely the upper valley of the

Durance (with those of its affluents, the Gyronde and the Guil), but also

the valley of the Dora Riparia (Césanne, Oulx, Bardonnèche and Exilles),

and that of the Chisone (Fénestrelles, Pérouse, Pragelas)--these glens all

lying on the eastern slope of the chain of the Alps. But by the treaty of

Utrecht (1713) all these valleys were handed over to Savoy in exchange for

that of Barcelonnette, on the west slope of the Alps. In 1815 Briançon

successfully withstood a siege of three months at the hands of the Allies,

a feat which is commemorated by an inscription on one of its gates, _Le

passé répond de l'avenir_.

(W. A. B. C.)

BRIAND, ARISTIDE (1862- ), French statesman, was born at Nantes, of a

bourgeois family. He studied law, and while still young took to politics,

associating himself with the most advanced movements, writing articles for

the anarchist journal _Le Peuple_, and directing the _Lanterne_ for some

time. From this he passed to the _Petite République_, leaving it to found,

with Jean Jaurès, _L'Humanité_. At the same time he was prominent in the

movement for the formation of labour unions, and at the congress of working

men at Nantes in 1894 he secured the adoption of the labour union idea

against the adherents of Jules Guesde. From that time, Briand became one of

the leaders of the French Socialist party. In 1902, after several

unsuccessful attempts, he was elected deputy. He declared himself a strong

partisan of the union of the Left in what is known as the _Bloc_, in order

to check the reactionary deputies of the Right. From the beginning of his

career in the chamber of deputies, Briand was occupied with the question of

the separation of church and state. He was appointed reporter of the

commission charged with the preparation of the law, and his masterly report

at once marked him out as one of the coming leaders. He succeeded in

carrying his project through with but slight modifications, and without

dividing the parties upon whose support he relied. He was the principal

author of the law of separation, but, not content with preparing it, he

wished to apply it as well, especially as the existing Rouvier [v.04

p.0516] ministry allowed disturbances to occur during the taking of

inventories of church property, a clause of the law for which Briand was

not responsible. Consequently he accepted the portfolio of public

instruction and worship in the Sarrien ministry (1906). So far as the

chamber was concerned his success was complete. But the acceptance of a

portfolio in a bourgeois ministry led to his exclusion from the Unified

Socialist party (March 1906). As opposed to Jaurès, he contended that the

Socialists should co-operate actively with the Radicals in all matters of

reform, and not stand aloof to await the complete fulfilment of their

ideals.

BRIANZA, a district of Lombardy, Italy, forming the south part of the

province of Como, between the two southern arms of the lake of that name.

It is thickly populated and remarkable for its fertility; and being hilly

is a favourite summer resort of the Milanese.

BRIARE, a town of north-central France in the department of Loiret on the

right bank of the Loire, 45½ m. S.E. of Orléans on the railway to Nevers.

Pop. (1906) 4613. Briare, the _Brivodorum_ of the Romans, is situated at

the extremity of the Canal of Briare, which unites the Loire and its

lateral canal with the Loing and so with the Seine. The canal of Briare was

constructed from 1605 to 1642 and is about 36 m. long. The industries

include the manufacture of fine pottery, and of so-called porcelain buttons

made of felspar and milk by a special process; its inventor, Bapterosses,

has a bust in the town. The canal traffic is in wood, iron, coal, building

materials, &c. A modern hospital and church, and the hôtel de ville

installed in an old moated château, are the chief buildings. The lateral

canal of the Loire crosses the Loire near Briare by a fine canal-bridge 720

yds. in length.

BRIAREUS, or AEGAEON, in Greek mythology, one of the three hundred-armed,

fifty-headed Hecatoncheires, brother of Cottus and Gyges (or Gyes).

According to Homer (_Iliad_ i. 403) he was called Aegaeon by men, and

Briareus by the gods. He was the son of Poseidon (or Uranus) and Gaea. The

legends regarding him and his brothers are various and somewhat

contradictory. According to the most widely spread myth, Briareus and his

brothers were called by Zeus to his assistance when the Titans were making

war upon Olympus. The gigantic enemies were defeated and consigned to

Tartarus, at the gates of which the three brothers were placed (Hesiod,

_Theog._ 624, 639, 714). Other accounts make Briareus one of the assailants

of Olympus, who, after his defeat, was buried under Mount Aetna

(Callimachus, _Hymn to Delos_, 141). Homer mentions him as assisting Zeus

when the other Olympian deities were plotting against the king of gods and

men (_Iliad_ i. 398). Another tradition makes him a giant of the sea, ruler

of the fabulous Aegaea in Euboea, an enemy of Poseidon and the inventor of

warships (Schol. on Apoll. Rhod. i. 1165). It would be difficult to

determine exactly what natural phenomena are symbolized by the

Hecatoncheires. They may represent the gigantic forces of nature which

appear in earthquakes and other convulsions, or the multitudinous motion of

the sea waves (Mayer, _Die Giganten und Titanen_, 1887).

BRIBERY (from the O. Fr. _briberie_, begging or vagrancy, _bribe_, Mid.

Lat. _briba_, signifying a piece of bread given to beggars; the Eng.

"bribe" has passed through the meanings of alms, blackmail and extortion,

to gifts received or given in order to influence corruptly). The public

offence of bribery may be defined as the offering or giving of payment in

some shape or form that it may be a motive in the performance of functions

for which the proper motive ought to be a conscientious sense of duty. When

this is superseded by the sordid impulses created by the bribe, a person is

said to be corrupted, and thus corruption is a term sometimes held

equivalent to bribery. The offence may be divided into two great

classes--the one where a person invested with power is induced by payment

to use it unjustly; the other, where power is obtained by purchasing the

suffrages of those who can impart it. It is a natural propensity, removable

only by civilization or some powerful counteracting influence, to feel that

every element of power is to be employed as much as possible for the

owner's own behoof, and that its benefits should be conferred not on those

who best deserve them, but on those who will pay most for them. Hence

judicial corruption is an inveterate vice of imperfect civilization. There

is, perhaps no other crime on which the force of law, if unaided by public

opinion and morals, can have so little influence; for in other crimes, such

as violence or fraud, there is generally some person immediately injured by

the act, who can give his aid in the detection of the offender, but in the

perpetration of the offence of bribery all the immediate parties obtain

what they desire, and are satisfied.

The purification of the bench from judicial bribery has been gradual in

most of the European countries. In France it received an impulse in the

16th century from the high-minded chancellor, Michel de L'Hôpital. In

England judicial corruption has been a crime of remarkable rarity. Indeed,

with the exception of a statute of 1384 (repealed by the Statute Law

Revision Act 1881) there has been no legislation relating to judicial

bribery. The earliest recorded case was that of Sir William Thorpe, who in

1351 was fined and removed from office for accepting bribes. Other

celebrated cases were those of Michael de la Pole, chancellor of England,

in 1387; Lord Chancellor Bacon in 1621; Lionel Cranfield, earl of

Middlesex, in 1624; and Sir Thomas Parker, 1st earl of Macclesfield, in

1725. In Scotland for some years after the Revolution the bench was not

without a suspicion of interested partiality; but since the beginning of

the 19th century, at least, there has been in all parts of the empire a

perfect reliance on its purity. The same may be said of the higher class of

ministerial officers. There is no doubt that in the period from the

Revolution to the end of Queen Anne's reign, when a speaker of the House of

Commons was expelled for bribery, and the great Marlborough could not clear

his character from pecuniary dishonesty, there was much corruption in the

highest official quarters. The level of the offence of official bribery has

gradually descended, until it has become an extremely rare thing for the

humbler officers connected with the revenue to be charged with it. It has

had a more lingering existence with those who, because their power is more

of a constitutional than an official character, have been deemed less

responsible to the public. During Walpole's administration there is no

doubt that members of parliament were paid in cash for votes; and the

memorable saying, that every man has his price, has been preserved as a

characteristic indication of his method of government. One of the forms in

which administrative corruption is most difficult of eradication is the

appointment to office. It is sometimes maintained that the purity which

characterizes the administration of justice is here unattainable, because

in giving a judgment there is but one form in which it can be justly given,

but when an office has to be filled many people may be equally fitted for

it, and personal motives must influence a choice. It very rarely happens,

however, that direct bribery is supposed to influence such appointments. It

does not appear that bribery was conspicuous in England until, in the early

part of the 18th century, constituencies had thrown off the feudal

dependence which lingered among them; and, indeed, it is often said, that

bribery is essentially the defect of a free people, since it is the sale of

that which is taken from others without payment.

In English law bribery of a privy councillor or a juryman (see EMBRACERY)

is punishable as a misdemeanour, as is the taking of a bribe by any

judicial or ministerial officer. The buying and selling of public offices

is also regarded at common law as a form of bribery. By the Customs

Consolidation Act 1876, any officer in the customs service is liable to

instant dismissal and a penalty of £500 for taking a bribe, and any person

offering or promising a bribe or reward to an officer to neglect his duty

or conceal or connive at any act by which the customs may be evaded shall

forfeit the sum of £200. Under the Inland Revenue Regulations Act 1890, the

bribery of commissioners, collectors, officers or other persons employed in

relation to the Inland Revenue involves a fine of £500. The Merchant

Shipping Act 1894, ss. 112 and 398, makes provision for certain offences in

the nature of bribery. Bribery is, by the Extradition Act 1906, [v.04

p.0517] an extraditable offence. Administrative corruption was dealt with

in the Public Bodies' Corrupt Practices Act 1889. The public bodies

concerned are county councils, town or borough councils, boards,

commissioners, select vestries and other bodies having local government,

public health or poor law powers, and having for those purposes to

administer rates raised under public general acts. The giving or receiving,

promising, offering, soliciting or agreeing to receive any gift, fee, loan

or advantage by any person as an inducement for any act or forbearance by a

member, officer or servant of a public body in regard to the affairs of

that body is made a misdemeanour in England and Ireland and a crime and

offence in Scotland. Prosecution under the act requires the consent of the

attorney or solicitor-general in England or Ireland and of the lord

advocate in Scotland. Conviction renders liable to imprisonment with or

without hard labour for a term not exceeding two years, and to a fine not

exceeding £500, in addition to or in lieu of imprisonment. The offender may

also be ordered to pay to the public body concerned any bribe received by

him; he may be adjudged incapable for seven years of holding public office,

_i.e._ the position of member, officer or servant of a public body; and if

already an officer or servant, besides forfeiting his place, he is liable

at the discretion of the court to forfeit his right to compensation or

pension. On a second conviction he may be adjudged forever incapable of

holding public office, and for seven years incapable of being registered or

of voting as a parliamentary elector, or as an elector of members of a

public body. An offence under the act may be prosecuted and punished under

any other act applicable thereto, or at common law; but no person is to be

punished twice for the same offence. Bribery at political elections was at

common law punishable by indictment or information, but numerous statutes

have been passed dealing with it as a "corrupt practice." In this sense,

the word is elastic in meaning and may embrace any method of corruptly

influencing another for the purpose of securing his vote (see CORRUPT

PRACTICES). Bribery at elections of fellows, scholars, officers and other

persons in colleges, cathedral and collegiate churches, hospitals and other

societies was prohibited in 1588-1589 by statute (31 Eliz. c. 6). If a

member receives any money, fee, reward or other profit for giving his vote

in favour of any candidate, he forfeits his own place; if for any such

consideration he resigns to make room for a candidate, he forfeits double

the amount of the bribe, and the candidate by or on whose behalf a bribe is

given or promised is incapable of being elected on that occasion. The act

is to be read at every election of fellows, &c., under a penalty of £40 in

case of default. By the same act any person for corrupt consideration

presenting, instituting or inducting to an ecclesiastical benefice or

dignity forfeits two years' value of the benefice or dignity; the corrupt

presentation is void, and the right to present lapses for that turn to the

crown, and the corrupt presentee is disabled from thereafter holding the

same benefice or dignity; a corrupt institution or induction is void, and

the patron may present. For a corrupt resignation or exchange of a benefice

the giver and taker of a bribe forfeit each double the amount of the bribe.

Any person corruptly procuring the ordaining of ministers or granting of

licenses to preach forfeits £40, and the person so ordained forfeits £10

and for seven years is incapacitated from holding any ecclesiastical

benefice or promotion.

In the United States the offence of bribery is very severely dealt with. In

many states, bribery or the attempt to bribe is made a felony, and is

punishable with varying terms of imprisonment, in some jurisdictions it may

be with a period not exceeding ten years. The offence of bribery at

elections is dealt with on much the same lines as in England, voiding the

election and disqualifying the offender from holding any office.

Bribery may also take the form of a secret commission (_q.v._), a profit

made by an agent, in the course of his employment, without the knowledge of

his principal.

BRIC À BRAC (a French word, formed by a kind of onomatopoeia, meaning a

heterogeneous collection of odds and ends; cf. _de bric et de broc_,

corresponding to our "by hook or by crook"; or by reduplication from

_brack_, refuse), objects of "virtu," a collection of old furniture, china,

plate and curiosities.

BRICK (derived according to some etymologists from the Teutonic _bricke_, a

disk or plate; but more authoritatively, through the French _brique_,

originally a "broken piece," applied especially to bread, and so to clay,

from the Teutonic _brikan_, to break), a kind of artificial stone generally

made of burnt clay, and largely used as a building material.

_History_.--The art of making bricks dates from very early times, and was

practised by all the civilized nations of antiquity. The earliest burnt

bricks known are those found on the sites of the ancient cities of

Babylonia, and it seems probable that the method of making strong and

durable bricks, by burning blocks of dried clay, was discovered in this

corner of Asia. We know at least that well-burnt bricks were made by the

Babylonians more than 6000 years ago, and that they were extensively used

in the time of Sargon of Akkad (c. 3800 B.C.). The site of the ancient city

of Babylon is still marked by huge mounds of bricks, the ruins of its great

walls, towers and palaces, although it has been the custom for centuries to

carry away from these heaps the bricks required for the building of the

modern towns in the surrounding country. The Babylonians and Assyrians

attained to a high degree of proficiency in brickmaking, notably in the

manufacture of bricks having a coating of coloured glaze or enamel, which

they largely used for wall decoration. The Chinese claim great antiquity

for their clay industries, but it is not improbable that the knowledge of

brickmaking travelled eastwards from Babylonia across the whole of Asia. It

is believed that the art of making glazed bricks, so highly developed

afterwards by the Chinese, found its way across Asia from the west, through

Persia and northern India, to China. The great wall of China was

constructed partly of brick, both burnt and unburnt; but this was built at

a comparatively late period (c. 210 B.C.), and there is nothing to show

that the Chinese had any knowledge of burnt bricks when the art flourished

in Babylonia.

Brickmaking formed the chief occupation of the Israelites during their

bondage in Egypt, but in this case the bricks were probably sun-dried only,

and not burnt. These bricks were made of a mixture of clay and chopped

straw or reeds, worked into a stiff paste with water. The clay was the

river mud from the banks of the Nile, and as this had not sufficient

cohesion in itself, the chopped straw (or reeds) was added as a binding

material. The addition of such substances increases the plasticity of wet

clay, especially if the mixture is allowed to stand for some days before

use; so that the action of the chopped straw was twofold; a fact possibly

known to the Egyptians. These sun-dried bricks, or "adobes," are still

made, as of old, on the banks of the Nile by the following method:--A

shallow pit or bed is prepared, into which are thrown the mud, chopped

straw and water in suitable proportions, and the whole mass is tramped on

until it is thoroughly mixed and of the proper consistence. This mixture is

removed in lumps and shaped into bricks, in moulds or by hand, the bricks

being simply sun-dried.

Pliny mentions that three kinds of bricks were made by the Greeks, but

there is no indication that they were used to any great extent, and

probably the walls of Athens on the side towards Mount Hymettus were the

most important brick-structures in ancient Greece. The Romans became

masters of the brickmaker's art, though they probably acquired much of

their knowledge in the East, during their occupation of Egypt and Greece.

In any case they revived and extended the manufacture of bricks about the

beginning of the Christian era; exercising great care in the selection and

preparation of their clay, and introducing the method of burning bricks in

kilns. They carried their knowledge and their methods throughout western

Europe, and there is abundant evidence that they made bricks extensively in

Germany and in Britain.

Although brickmaking was thus introduced into Britain nearly 2000 years

ago, the art seems to have been lost when the Romans withdrew from the

country, and it is doubtful whether any burnt bricks were made in England

from that time until the 13th century. Such bricks as were used during this

long [v.04 p.0518] period were generally taken from the remains of Roman

buildings, as at Colchester and St Albans Abbey. One of the earliest

existing brick buildings, erected after the revival of brickmaking in

England, is Little Wenham Hall, in Suffolk, built about A.D. 1210; but it

was not until the 15th century that bricks came into general use again, and

then only for important edifices. During the reign of Henry VIII.

brickmaking was brought to great perfection, probably by workmen brought

from Flanders, and the older portions of St James's Palace and Hampton

Court Palace remain to testify to the skill then attained. In the 16th

century bricks were increasingly used, but down to the Great Fire of

London, in 1666, the smaller buildings, shops and dwelling-houses, were

constructed of timber framework filled in with lath and plaster. In the

rebuilding of London after the fire, bricks were largely used, and from the

end of the 17th century to the present day they have been almost

exclusively used in all ordinary buildings throughout the country, except

in those districts where building stone is plentiful and good brick-clay is

not readily procurable. The bricks made in England before 1625 were of many

sizes, there being no recognized standard; but in that year the sizes were

regulated by statute, and the present standard size was adopted, viz. 9 x

4½ x 3 in. In 1784 a tax was levied on bricks, which was not repealed until

1850. The tax averaged about 4s. 7d. per thousand on ordinary bricks, and

special bricks were still more heavily taxed.

The first brick buildings in America were erected on Manhattan Island in

the year 1633 by a governor of the Dutch West India Company. These bricks

were made in Holland, where the industry had long reached great excellence;

and for many years bricks were imported into America from Holland and from

England. In America burnt bricks were first made at New Haven about 1650,

and the manufacture slowly spread through the New England states; but for

many years the home-made article was inferior to that imported from Europe.

The Dutch and the Germans were the great brickmakers of Europe during the

middle ages, although the Italians, from the 14th to the 15th century,

revived and developed the art of decorative brick-work or terra-cotta, and

discovered the method of applying coloured enamels to these materials.

Under the Della Robbias, in the 15th century, some of the finest work of

this class that the world has seen was executed, but it can scarcely be

included under brickwork.

_Brick Clays_.--All clays are the result of the denudation and

decomposition of felspathic and siliceous rocks, and consist of the fine

insoluble particles which have been carried in suspension in water and

deposited in geologic basins according to their specific gravity and degree

of fineness (see CLAY). These deposits have been formed in all geologic

epochs from the "Recent" to the "Cambrian," and they vary in hardness from

the soft and plastic "alluvial" clays to the hard and rock-like shales and

slates of the older formations. The alluvial and drift clays (which were

alone used for brickmaking until modern times) are found near the surface,

are readily worked and require little preparation, whereas the older

sedimentary deposits are often difficult to work and necessitate the use of

heavy machinery. These older shales, or rocky clays, may be brought into

plastic condition by long weathering (_i.e._ by exposure to rain, frost and

sun) or by crushing and grinding in water, and they then resemble ordinary

alluvial clays in every respect.

The clays or earths from which burnt bricks are made may be divided into

two principal types, according to chemical composition: (1) Clays or shales

containing only a small percentage of carbonate of lime and consisting

chiefly of hydrated aluminium silicates (the "true clay substance") with

more or less sand, undecomposed grains of felspar, and oxide or carbonate

of iron; these clays usually burn to a buff, salmon or red colour; (2)

Clays containing a considerable percentage of carbonate of lime in addition

to the substances above mentioned. These latter clay deposits are known as

"marls,"[1] and may contain as much as 40% of chalk. They burn to a

sulphur-yellow colour which is quite distinctive.

Brick clays of class (1) are very widely distributed, and have a more

extensive geological range than the marls, which are found in connexion

with chalk or limestone formations only. These ordinary brick clays vary

considerably in composition, and many clays, as they are found in nature,

are unsuitable for brickmaking without the addition of some other kind of

clay or sand. The strongest brick clays, _i.e._ those possessing the

greatest plasticity and tensile strength, are usually those which contain

the highest percentage of the hydrated aluminium silicates, although the

exact relation of plasticity to chemical composition has not yet been

determined. This statement cannot be applied indiscriminately to all clays,

but may be taken as fairly applicable to clays of one general type (see

CLAY). All clays contain more or less free silica in the form of sand, and

usually a small percentage of undecomposed felspar. The most important

ingredient, after the clay-substance and the sand, is oxide of iron; for

the colour, and, to a less extent, the hardness and durability of the burnt

bricks depend on its presence. The amount of oxide of iron in these clays

varies from about 2 to 10%, and the colour of the bricks varies accordingly

from light buff to chocolate; although the colour developed by a given

percentage of oxide of iron is influenced by the other substances present

and also by the method of firing. A clay containing from 5 to 8% of oxide

of iron will, under ordinary conditions of firing, produce a red brick; but

if the clay contains 3 to 4% of alkalis, or the brick is fired too hard,

the colour will be darker and more purple. The actions of the alkalis and

of increased temperature are probably closely related, for in either case

the clay is brought nearer to its fusion point, and ferruginous clays

generally become darker in colour as they approach to fusion. Alumina acts

in the opposite direction, an excess of this compound tending to make the

colour lighter and brighter. It is impossible to give a typical composition

for such clays, as the percentages of the different constituents vary

through such wide ranges. The clay substance may vary from 15 to 80%, the

free silica or sand from 5 to 80%, the oxide of iron from 1 to 10%, the

carbonates of lime and magnesia together, from 1 to 5%, and the alkalis

from 1 to 4%. Organic matter is always present, and other impurities which

frequently occur are the sulphates of lime and magnesia, the chlorides and

nitrates of soda and potash, and iron-pyrites. The presence of organic

matter gives the wet clay a greater plasticity, probably because it forms a

kind of mucilage which adds a certain viscosity and adhesiveness to the

natural plasticity of the clay. In some of the coal-measure shales the

amount of organic matter is very considerable, and may render the clay

useless for brickmaking. The other impurities, all of which, except the

pyrites, are soluble in water, are undesirable, as they give rise to

"scum," which produces patchy colour and pitted faces on the bricks. The

commonest soluble impurity is calcium sulphate, which produces a whitish

scum on the face of the brick in drying, and as the scum becomes

permanently fixed in burning, such bricks are of little use except for

common work. This question of "scumming" is very important to the maker of

high-class facing and moulded bricks, and where a clay containing calcium

sulphate must be used, a certain percentage of barium carbonate is nowadays

added to the wet clay. By this means the calcium sulphate is converted into

calcium carbonate which is insoluble in water, so that it remains

distributed throughout the mass of the brick instead of being deposited on

the surface. The presence of magnesium salts is also very objectionable, as

these generally remain in the burnt brick as magnesium sulphate, which

gives rise to an efflorescence of fine white crystals after the bricks are

built into position. Clays which are strong or plastic are known as "fat"

clays, and they always contain a high percentage of true "clay substance,"

and, consequently, a low percentage of sand. Such clays take up a

considerable amount of water in "tempering"; they dry slowly, shrink

greatly, and so become liable to lose their shape and develop cracks in

drying and firing. "Fat" clays are greatly improved by the addition of

coarse sharp sand, [v.04 p.0519] which reduces the time of drying and the

shrinkage, and makes the brick more rigid during the firing. Coarse sand,

unlike clay-substance, is practically unaffected during the drying and

firing, and is a desirable if not a necessary ingredient of all brick

clays. The best brick-clays feel gritty between the fingers; they should,

of course, be free from pebbles, sufficiently plastic to be moulded into

shape and strong enough when dry to be safely handled. All clays are

greatly improved by being turned over and exposed to the weather, or by

standing for some months in a wet condition. This "weathering" and "ageing"

of clay is particularly important where bricks are made from tempered clay,

_i.e._ clay in the wet or plastic state; where bricks are made from shale,

in the semi-plastic condition, weathering is still of importance.

The lime clays or "marls" of class (2), which contain essentially a high

percentage of chalk or limestone, are not so widely distributed as the

ordinary brick-clays, and in England the natural deposits of these clays

have been largely exhausted. A very fine chalk-clay, or "malm" as it was

locally called, was formerly obtained from the alluvium in the vicinity of

London; but the available supply of this has been used up, and at the

present time an artificial "malm" is prepared by mixing an ordinary

brick-clay with ground chalk. For the best London facing-bricks the clay

and chalk are mixed in water. The chalk is ground on grinding-pans, and the

clay is mixed with water and worked about until the mixture has the

consistence of cream. The mixture of these "pulps" is run through a grating

or coarse sieve on to a drying-kiln or "bed," where it is allowed to stand

until stiff enough to walk on. A layer of fine ashes is then spread over

the clay, and the mass is turned over and mixed by spade, and tempered by

the addition of water. In other districts, where clays containing limestone

are used, the marl is mixed with water on a wash-pan and the resulting

creamy fluid passed through coarse sieves on to a drying-bed. If necessary,

coarse sand is added to the clay in the wash-pan, and such addition is

often advisable because the washed clays are generally very fine in grain.

Another method of treating these marls, when they are in the plastic

condition, is to squeeze them by machinery through iron gratings, which

arrest and remove the pebbles. In other cases the marl is passed through a

grinding-mill having a solid bottom and heavy iron rollers, by which means

the limestone pebbles are crushed sufficiently and mixed through the whole

mass. The removal of limestone pebbles from the clay is of great

importance, as during the firing they would be converted into quicklime,

which has a tendency to shatter the brick on exposure to the weather. As

before stated, these marls (which usually contain from 15 to 30% of calcium

carbonate) burn to a yellow colour which is quite distinctive, although in

some cases, where the percentage of limestone is very high, over 40%, the

colour is grey or a very pale buff. The action of lime in bleaching the

ferric oxide and producing a yellow instead of a red brick, has not been

thoroughly investigated, but it seems probable that some compound is

produced, between the lime and the oxide of iron, or between these two

oxides and the free silica, entirely different from that produced by oxide

of iron in the absence of lime. Such marls require a harder fire than the

ordinary brick-clays in order to bring about the reaction between the lime

and the other ingredients. Magnesia may replace lime to some extent in such

marls, but the firing temperature must be higher when magnesia is present.

Marls usually contract very little, if at all, in the burning, and

generally produce a strong, square brick of fine texture and good colour.

When under-fired, marl bricks are very liable to disintegrate under the

action of the weather, and great care must be exercised in burning them at

a sufficiently high temperature.

_Brickmaking_.--Bricks made of tempered clay may be made by hand or by

machine, and the machines may be worked by hand or by mechanical power.

Bricks made of semi-plastic clay (_i.e._ ground clay or shale sufficiently

damp to adhere under pressure) are generally machine-made throughout. The

method of making bricks by hand is the same, with slight variation, the

world over. The tempered clay is pressed by hand into a wooden or metal

mould or four-sided case (without top or bottom) which is of the desired

shape and size, allowance being made for the shrinkage of the brick in

drying and firing. The moulder stands at the bench or table, dips the mould

in water, or water and then sand, to prevent the clay from sticking, takes

a rudely shaped piece of clay from an assistant, and dashes this into the

mould which rests on the moulding bench. He then presses the clay into the

corners of the mould with his fingers, scrapes off any surplus clay and

levels the top by means of a strip of wood called a "strike," and then

turns the brick out of the mould on to a board, to be carried away by

another assistant to the drying-ground. The mould may be placed on a

special piece of wood, called the stock-board, provided with an elevated

tongue of wood in the centre, which produces the hollow or "frog" in the

bottom of the brick.

Machine-made bricks may be divided into two kinds, plastic and

semi-plastic, although the same type of machine is often used for both

kinds.

The machine-made plastic bricks are made of tempered clay, but generally

the tempering and working of the clay are effected by the use of machinery,

especially when the harder clays and shales are used. The machines used in

the preparation of such clays are grinding-mills and pug-mills. The

grinding-mills are either a series of rollers with graduated spaces

between, through which the clay or shale is passed, or are of the ordinary

"mortar pan" type, having a solid or perforated iron bottom on which the

clay or shale is crushed by heavy rollers. Shales are sometimes passed

through a grinding-mill before they are exposed to the action of the

weather, as the disintegration of the hard lumps of shale greatly

accelerates the "weathering." In the case of ordinary brick-clay, in the

plastic condition, grinding-mills are only used when pebbles more than a

quarter of an inch in diameter are present, as otherwise the clay may be

passed directly through the pug-mill, a process which may be repeated if

necessary. The pug-mill consists of a box or trough having a feed hole at

one end and a delivery hole or nose at the other end, and provided with a

central shaft which carries knives and cutters so arranged that when the

shaft revolves they cut and knead the clay, and at the same time force it

towards and through the delivery nose. The cross section of this nose of

the pug-mill is approximately the same as that of the required brick (9 in.

× 4½ in. plus contraction, for ordinary bricks), so that the pug delivers a

solid or continuous mass of clay from which bricks may be made by merely

making a series of square cuts at the proper distances apart. In practice,

the clay is pushed from the pug along a smooth iron plate, which is

provided with a wire cutting frame having a number of tightly stretched

wires placed at certain distances apart, arranged so that they can be

brought down upon, and through, the clay, and so many bricks cut off at

intervals. The frame is sometimes in the form of a skeleton cylinder, the

wires being arranged radially (or the wires may be replaced by metal

disks); but in all cases bricks thus made are known as "wire-cuts." In

order to obtain a better-shaped and more compact brick, these wire-cuts may

be placed under a brick press and there squeezed into iron moulds under

great pressure. These two processes are now generally performed by one

machine, consisting of pug-mill and brick press combined. The pug delivers

the clay, downwards, into the mould; the proper amount of clay is cut off;

and the mould is made to travel into position under the ram of the press,

which squeezes the clay into a solid mass.

There are many forms of brick press, a few for hand power, but the most

adapted for belt-driving; although in recent years hydraulic presses have

come more and more into use, especially in Germany and America. The

essential parts of a brick press are: (1) a box or frame in which the clay

is moulded; (2) a plunger or die carried on the end of a ram, which gives

the necessary pressure; (3) an arrangement for pushing the pressed brick

out of the moulding box. Such presses are generally made of iron

throughout, although other metals are used, occasionally, for the moulds

and dies. The greatest variations found in brick presses are in the means

adopted for actuating the ram; and many ingenious mechanical devices have

been applied to this end, each claiming some particular advantage over its

predecessors. In many recent presses, especially where semi-plastic clay is

used, the brick is pressed simultaneously from top and bottom, a second

ram, working upwards from beneath, giving the additional pressure.

Although the best bricks are still pressed from tempered or plastic clay,

there has recently been a great development in the manufacture of

semi-plastic or dust-made bricks, especially in those districts where

shales are used for brickmaking. These semi-plastic bricks are stamped out

of ground shale that has been sufficiently moistened with water to enable

it to bind together. The hard-clay, or shale, is crushed under heavy

rollers in an iron grinding-pan having a perforated bottom through which

the crushed clay passes, when sufficiently fine, into a small compartment

underneath. This clay powder is then delivered, by an elevator, into a

sieve or screen, which retains the coarser particles for regrinding. Sets

of rollers may also be used for crushing shales that are only moderately

hard, the ground material being sifted as before. The material, as fed

[v.04 p.0520] into the mould of the press, is a coarse, damp powder which

becomes adhesive under pressure, producing a so-called "semi-plastic"

brick. The presses used are similar to those employed for plastic clay, but

they are generally more strongly and heavily built, and are capable of

applying a greater pressure.

The semi-plastic method has many advantages where shales are used, although

the bricks are not as strong nor as perfect as the best "plastic" bricks.

The method, however, enables the brickmaker to make use of certain kinds of

clay-rock, or shale, that would be impracticable for plastic bricks; and

the weathering, tempering and "ageing" may be largely or entirely dispensed

with. The plant required is heavier and more costly, but the brickyard

becomes more compact, and the processes are simpler than with the "plastic"

method.

The drying of bricks, which was formerly done in the open, is now, in most

cases, conducted in a special shed heated by flues along which the heated

gases from the kilns pass on their way to the chimney. It is important that

the atmosphere of the drying-shed should be fairly dry, to which end

suitable means of ventilation must be arranged (by fans or otherwise). If

the atmosphere is too moist the surface of the brick remains damp for a

considerable time, and the moisture from the interior passes to the surface

as water, carrying with it the soluble salts, which are deposited on the

surface as the water slowly evaporates. This deposit produces the "scum"

already referred to. When the drying is done in a dry atmosphere the

surface quickly dries and hardens, and the moisture from the interior

passes to the surface as vapour, the soluble salts being left distributed

through the whole mass, and consequently no "scum" is produced. Plastic

bricks take much longer to dry than semi-plastic; they shrink more and have

a greater tendency to warp or twist.

The burning or firing of bricks is the most important factor in their

production; for their strength and durability depend very largely on the

character and degree of the firing to which they have been subjected. The

action of the heat brings about certain chemical decompositions and

re-combinations which entirely alter the physical character of the dry

clay. It is important, therefore, that the firing should be carefully

conducted and that it should be under proper control. For ordinary bricks

the firing atmosphere should be oxidizing, and the finishing temperature

should be adjusted to the nature of the clay, the object being to produce a

hard strong brick, of good shape, that will not be too porous and will

withstand the action of frost. The finishing temperature ranges from 900°

C. to 1250° C., the usual temperature being about 1050° C. for ordinary

bricks. As before mentioned, lime-clays require a higher firing temperature

(usually about 1150° C. to 1200° C.) in order to bring the lime into

chemical combination with the other substances present.

It is evident that the best method of firing bricks is to place them in

permanent kilns, but although such kilns were used by the Romans some 2000

years ago, the older method of firing in "clamps" is still employed in the

smaller brickfields, in every country where bricks are made. These clamps

are formed by arranging the unfired bricks in a series of rows or walls,

placed fairly closely together, so as to form a rectangular stack. A

certain number of channels, or firemouths, are formed in the bottom of the

clamp; and fine coal is spread in horizontal layers between the bricks

during the building up of the stack. Fires are kindled in the fire-mouths,

and the clamp is allowed to go on burning until the fuel is consumed

throughout. The clamp is then allowed to cool, after which it is taken

down, and the bricks sorted; those that are under-fired being built up

again in the next clamp for refiring. Sometimes the clamp takes the form of

a temporary kiln, the outside being built of burnt bricks which are

plastered over with clay, and the fire-mouths being larger and more

carefully formed. There are many other local modifications in the manner of

building up the clamps, all with the object of producing a large percentage

of well-fired bricks. Clamp-firing is slow, and also uneconomical, because

irregular and not sufficiently under control; and it is now only employed

where bricks are made on a small scale.

Brick-kilns are of many forms, but they can all be grouped under two main

types--Intermittent kilns and Continuous kilns. The intermittent kiln is

usually circular in plan, being in the form of a vertical cylinder with a

domed top. It consists of a single firing-chamber in which the unfired

bricks are placed, and in the walls of which are contrived a number of

fire-mouths where wood or coal is burned. In the older forms known as

_up-draught_ kilns, the products of combustion pass from the fire-mouth,

through flues, into the bottom of the firing-chamber, and thence directly

upwards and out at the top. The modern plan is to introduce the products of

combustion near the top, or crown, of the kiln, and to draw them downwards

through holes in the bottom which lead to flues connected with an

independent chimney. These _down-draught_ kilns have short chimneys or

"bags" built round the inside wall in connexion with the fire-mouths, which

conduct the flames to the upper part of the firing-chamber, where they are

reverberated and passed down through the bricks in obedience to the pull of

the chimney. The "bags" may be joined together, forming an inner circular

wall entirely round the firing-chamber, except at the doorway; and a number

of kilns may be built in a row or group having their bottom flues connected

with the same tall chimney. Down-draught kilns usually give a more regular

fire and a higher percentage of well-fired bricks; and they are more

economical in fuel consumption than up-draught kilns, while the hot gases,

as they pass from the kiln, may be utilized for drying purposes, being

conducted through flues under the floor of the drying-shed, on their way to

the chimney. The method of using one tall chimney to work a group of

down-draught kilns naturally led to the invention of the "continuous" kiln,

which is really made up of a number of separate kilns or firing-chambers,

built in series and connected up to the main flue of the chimney in such a

manner that the products of combustion from one kiln may be made to pass

through a number of other kilns before entering the flue. The earliest form

of continuous kiln was invented by Friedrich Hoffman, and all kilns of this

type are built on the Hoffman principle, although there are a great number

of modifications of the original Hoffman construction. The great principle

of "continuous" firing is the utilization of the waste heat from one kiln

or section of a kiln in heating up another kiln or section, direct firing

being applied only to finish the burning. In practice a number of kilns or

firing-chambers, usually rectangular in plan, are built side by side in two

parallel lines, which are connected at the ends by other kilns so as to

make a complete circuit. The original form of the complete series was

elliptical in plan, but the tendency in recent years has been to flatten

the sides of the ellipse and bring them together, thus giving two parallel

rows joined at the ends by a chamber or passage at right angles. Coal or

gas is burnt in the chamber or section that is being fired-up, the air

necessary for the combustion being heated on its passage through the kilns

that are cooling down, and the products of combustion, before entering the

chimney flue, are drawn through a number of other kilns or chambers

containing unfired bricks, which are thus gradually heated up by the

otherwise waste-heat from the sections being fired. Continuous kilns

produce a more evenly fired product than the intermittent kilns usually do,

and, of course, at much less cost for fuel. Gas firing is now being

extensively applied to continuous kilns, natural gas in some instances

being used in the United States of America; and the methods of construction

and of firing are carried out with greater care and intelligence, the prime

objects being economy of fuel and perfect control of firing. Pyrometers are

coming into use for the control of the firing temperature, with the result

that a constant and trustworthy product is turned put. The introduction of

machinery greatly helped the brickmaking industry in opening up new sources

of supply of raw material in the shales and hardened clays of the

sedimentary deposits of the older geologic formations, and, with the

extended use of continuous firing plants, it has led to the establishment

of large concerns where everything is co-ordinated for the production of

enormous quantities of bricks at a minimum cost. In the United Kingdom, and

still more in Germany and the United States of America, great improvements

have been made in machinery, firing-plant and organization, so that the

whole manufacture is now being conducted on more scientific lines, to the

great advantage of the industry.

_Blue Brick_ is a very strong vitreous brick of dark, slaty-blue colour,

used in engineering works where great strength or impermeability is

desirable. These bricks are made of clay containing front 7 to 10% of oxide

of iron, and their manufacture is carried out in the ordinary way until the

later stages of the firing process, when they are subjected to the strongly

reducing action of a smoky atmosphere, which is produced by throwing small

bituminous coal upon the fire-mouths and damping down the admission of air.

The smoke thus produced reduces the red ferric oxide to blue-green ferrous

oxide, or to metallic iron, which combines with the silica present to form

a fusible ferrous silicate. This fusible "slag" partly combines with the

other silicates present, and partly fills up the pores, and so produces a

vitreous impermeable layer varying in thickness according to the duration

and character of the smoking, the finishing temperature of the kiln and the

texture of the brick. Particles of carbon penetrate the surface during the

early stages of the smoking, and a small quantity of carbon probably enters

into combination, tending to produce a harder surface and darker colour.

_Floating Bricks_ were first mentioned by Strabo, the Greek geographer, and

afterwards by Pliny as being made at Pitane in the Troad. The secret of

their manufacture was lost for many centuries, but was rediscovered in 1791

by Fabroni, an Italian, who made them from the fossil meal (diatomaceous

earth) found in Tuscany. These bricks are very light, fairly strong, and

being poor conductors of heat, have been employed for the construction of

powder-magazines on board ship, &c.

_Mortar Bricks_ belong to the class of unburnt bricks, and are, strictly

speaking, blocks of artificial stone made in brick moulds. These bricks

have been made for many years by moulding a mixture of sand and slaked lime

and allowing the blocks thus made to harden in the air. This hardening is

brought about partly by evaporation of the water, but chiefly by the

conversion of the calcium hydrate, or slaked lime, into calcium carbonate

by the action of the carbonic acid in the atmosphere. A small proportion of

the lime enters into combination with the silica and water present to form

hydrated calcium silicate, and probably a little hydrated basic carbonate

of lime is also formed, both of which substances are in the nature of

cement. This process of natural hardening by exposure to the air was a very

long one, occupying from six to eighteen months, and many improvements were

introduced during the latter half of the 19th century to improve the

strength of the bricks and to hasten the hardening. [v.04 p.0521] Mixtures

of sand, lime and cement (and of certain ground blast-furnace slags and

lime) were introduced; the moulding was done under hydraulic presses and

the bricks afterwards treated with carbon dioxide under pressure, with or

without the application of mild heat. Some of these mixtures and methods

are still in use, but a new type of mortar brick has come into use during

recent years which has practically superseded the old mortar brick.

_Sand-lime Bricks_.--In the early 'eighties of the 19th century, Dr

Michaelis of Berlin patented a new process for hardening blocks made of a

mixture of sand and lime by treating them with high-pressure steam for a

few hours, and the so-called _sand-lime_ bricks are now made on a very

extensive scale in many countries. There are many differences of detail in

the manufacture, but the general method is in all cases the same. Dry sand

is intimately mixed with about one-tenth of its weight of powdered slaked

lime, the mixture is then slightly moistened with water and afterwards

moulded into bricks under powerful presses, capable of exerting a pressure

of about 60 tons per sq. in. After removal from the press the bricks are

immediately placed in huge steel cylinders usually 60 to 80 ft. long and

about 7 ft. in diameter, and are there subjected to the action of

high-pressure steam (120 lb to 150 lb per sq. in.) for from ten to fifteen

hours. The proportion of slaked lime to sand varies according to the nature

of the lime and the purity and character of the sand, one of lime to ten of

sand being a fair average. The following is an analysis of a typical German

sand-lime brick: silica (SiO_2), 84%; lime (CaO), 7%; alumina and oxide of

iron, 2%; water, magnesia and alkalis, 7%. Under the action of the

high-pressure steam the lime attacks the particles of sand, and a chemical

compound of water, lime and silica is produced which forms a strong bond

between the larger particles of sand. This bond of hydrated calcium

silicate is evidently different from, and of better type than, the filling

of calcium carbonate produced in the mortar-brick, and the sand-lime brick

is consequently much stronger than the ordinary mortar-brick, however the

latter may be made. The sand-lime brick is simple in manufacture, and with

reasonable care is of constant quality. It is usually of a light-grey

colour, but may be stained by the addition of suitable colouring oxides or

pigments unaffected by lime and the conditions of manufacture.

_Strength of Brick._--The following figures indicate the crushing load for

bricks of various types in tons per sq. in.:--

Common hand-made from 0.4 to 0.9

" machine-made " 0.9 " 1.2

London stock " 0.7 " 1.3

Staffordshire blue " 2.8 " 3.3

Sand-lime " 2.9 " 3.4

FIG. 6.--BURTON-UNION SYSTEM OF CLEANSING. (MESSRS. ALLSOPP'S BREWERY.)