FOOTNOTES:

[1] The census is taken every ten years, save in these three

provinces, where it is taken every five. Their population in 1906

was:--Manitoba, 360,000; Saskatchewan, 257,000; Alberta, 184,000.

[2] The areas assigned to Prince Edward Island, Nova Scotia, New

Brunswick and British Columbia are exclusive of the territorial seas,

that to Quebec is exclusive of the Gulf of St Lawrence (though

including the islands lying within it), and that to Ontario is

exclusive of the Canadian portion of the Great Lakes. About 500,000

sq. m. belong to the Arctic region and 125,755 sq. m. are water.

[3] In Canada a city must have over 10,000 inhabitants, a town over

2000.

[4] The date of foundation is given in brackets.

CANAL (from Lat. _canalis_, "channel" and "kennel" being doublets of the

word), an artificial water course used for the drainage of low lands,

for irrigation (q.v.), or more especially for the purpose of navigation

by boats, barges or ships. Probably the first canals were made for

irrigation, but in very early times they came also to be used for

navigation, as in Assyria and Egypt. The Romans constructed various

works of the kind, and Charlemagne projected a system of waterways

connecting the Main and the Rhine with the Danube, while in China the

Grand Canal, joining the Pei-ho and Yang-tse-Kiang and constructed in

the 13th century, formed an important artery of commerce, serving also

for irrigation. But although it appears from Marco Polo that inclines

were used on the Grand Canal, these early waterways suffered in general

from the defect that no method being known of conveniently transferring

boats from one level to another they were only practicable between

points that lay on nearly the same level; and inland navigation could

not become generally useful and applicable until this defect had been

remedied by the employment of locks. Great doubts exist as to the

person, and even the nation, that first introduced locks. Some writers

attribute their invention to the Dutch, holding that nearly a century

earlier than in Italy locks were used in Holland where canals are very

numerous, owing to the favourable physical conditions. On the other

hand, the contrivance has been claimed for engineers of the Italian

school, and it is said that two brothers Domenico of Viterbo constructed

a lock-chamber enclosed by a pair of gates in 1481, and that in 1487

Leonardo da Vinci completed six locks uniting the canals of Milan. Be

that as it may, however, the introduction of locks in the 14th or 15th

century gave a new character to inland navigation and laid the basis of

its successful extension.

The Languedoc Canal (Canal du Midi) may be regarded as the pioneer of

the canals of modern Europe. Joining the Bay of Biscay and the

Mediterranean it is 148 m. long and rises 620 ft. above sea-level with

119 locks, its depth being about 6-1/2 ft. It was designed by Baron Paul

Riquet de Bonrepos (1604-1680) and was finished in 1681. With it and the

still earlier Briare canal (1605-1642) France began that policy of canal

construction which has provided her with over 3000 m. of canals, in

addition to over 4600 m. of navigable rivers. In Russia Peter the Great

undertook the construction of a system of canals about the beginning of

the 18th century, and in Sweden a canal with locks, connecting

Eskilstuna with Lake Malar, was finished in 1606. In England the oldest

artificial canal is the Foss Dyke, a relic of the Roman occupation. It

extends from Lincoln to the river Trent near Torksey (11 m.), and formed

a continuation of the Caer Dyke, also of Roman origin but now filled up,

which ran from Lincoln to Peterborough (40 m.). Camden in his

_Britannia_ says that the Foss Dyke was deepened and to some extent

rendered navigable in 1121. Little, however, was done in making canals

in Great Britain until the middle of the 18th century, though before

that date some progress had been made in rendering some of the larger

rivers navigable. In 1759 the duke of Bridgewater obtained powers to

construct a canal between Manchester and his collieries at Worsley, and

this work, of which James Brindley was the engineer, and which was

opened for traffic in 1761, was followed by a period of great activity

in canal construction, which, however, came to an end with the

introduction of railways. According to evidence given before the royal

commission on canals in 1906 the total mileage of existing canals in the

United Kingdom was 3901. In the United States the first canal was made

in 1792-1796 at South Hadley, Massachusetts, and the canal-system,

though its expansion was checked by the growth of railways, has attained

a length of 4200 m., most of the mileage being in New York, Ohio, and

Pennsylvania. The splendid inland navigation system of Canada mainly

consists of natural lakes and rivers, and the artificial waterways are

largely "lateral" canals, cut in order to enable vessels to avoid rapids

in the rivers. (See the articles on the various countries for accounts

of the canal-systems they possess.)

The canals that were made in the early days of canal-construction were

mostly of the class known as _barge_ or _boat canals_, and owing to

their limited depth and breadth were only available for vessels of small

size. But with the growth of commerce the advantage was seen of cutting

canals of such dimensions as to enable them to accommodate sea-going

ships. Such _ship-canals_, which from an engineering point of view

chiefly differ from barge-canals in the magnitude of the works they

involve, have mostly been constructed either to shorten the voyage

between two seas by cutting through an intervening isthmus, or to

convert important inland places into seaports. An early example of the

first class is afforded by the Caledonian Canal (q.v.), while among

later ones may be mentioned the Suez Canal (q.v.), the Kaiser Wilhelm,

Nord-Ostsee or Kiel Canal, connecting Brunsbuttel at the mouth of the

Elbe with Kiel (q.v.) on the Baltic, and the various canals that have

been proposed across the isthmus that joins North and South America (see

PANAMA CANAL). Examples of the second class are the Manchester Ship

Canal and the canal that runs from Zeebrugge on the North Sea to Bruges

(q.v.).

_Construction._--In laying out a line of canal the engineer is more

restricted than in forming the route of a road or a railway. Since water

runs downhill, gradients are inadmissible, and the canal must either be

made on one uniform level or must be adapted to the general rise or fall

of the country through which it passes by being constructed in a series

of level reaches at varying heights above a chosen datum line, each

closed by a lock or some equivalent device to enable vessels to be

transferred from one to another. To avoid unduly heavy earthwork, the

reaches must closely follow the bases of hills and the windings of

valleys, but from time to time it will become necessary to cross a

sudden depression by the aid of an embankment or aqueduct, while a piece

of rising ground or a hill may involve a cutting or a tunnel. Brindley

took the Bridgewater canal over the Irwell at Barton by means of an

aqueduct of three stone arches, the centre one having a span of 63 ft.,

and T. Telford arranged that the Ellesmere canal should cross the Dee

valley at Pont-y-Cysyllte partly by embankment and partly by aqueduct.

The embankment was continued till it was 75 ft. above the ground, when

it was succeeded by an aqueduct, 1000 ft. long and 127 ft. above the

river, consisting of a cast iron trough supported on iron arches with

stone piers. Occasionally when a navigable stream has to be crossed, a

swing viaduct is necessary to allow shipping to pass. The first was that

built by Sir E. Leader Williams to replace Brindley's aqueduct at

Barton, which was only high enough to give room for barges (see

MANCHESTER SHIP CANAL). One of the earliest canal tunnels was made in

1766-1777 by Brindley at Harecastle on the Trent and Mersey canal; it is

2880 yds. long, 12 ft. high and 9 ft. wide, and has no tow-path, the

boats being propelled by men lying on their backs and pushing with their

feet against the tunnel walls ("leggers"). A second tunnel, parallel to

this but 16 ft. high and 14 ft. wide, with a tow-path, was finished by

Telford in 1827. Standedge tunnel, on the Huddersfield canal, is over 3

m. long, and is also worked by leggers.

Dimensions.

The dimensions of a canal, apart from considerations of water-supply,

are regulated by the size of the vessels which are to be used on it.

According to J.M. Rankine, the depth of water and sectional area of

waterway should be such as not to cause any material increase of the

resistance to the motion of the boats beyond what would be encountered

in open water, and he gives the following rules as fulfilling these

conditions:--

Least breadth of bottom = 2 X greatest breadth of boat.

Least depth of water = 1-1/2 ft. + greatest draught of boat.

Least area of waterway = 6 X greatest midship section of boat.

The ordinary inland canal is commonly from 25 to 30 ft. wide at the

bottom, which is flat, and from 40 to 50 ft. at the water level, with a

depth of 4 or 5 ft., the angle of slope of the sides varying with the

nature of the soil. To retain the water in porous ground, and especially

on embankments, a strong watertight lining of puddle or tempered clay

must be provided on the bed and sides of the channel. Puddle is made of

clay which has been finely chopped up with narrow spades, water being

supplied until it is in a semi-plastic state. It is used in thin layers,

each of which is worked so as to be firmly united with the lower

stratum. The full thickness varies from 2 to 3 ft. To prevent the

erosion of the sides at the water-line by the wash from the boats, it

may be necessary to pitch them with stones or face them with brushwood.

In some of the old canals the slopes have been cut away and vertical

walls built to retain the towing-paths, with the result of adding

materially to the sectional area of the waterway.

Water supply.

A canal cannot be properly worked without a supply of water calculated

to last over the driest season of the year. If there be no natural lake

available in the district for storage and supply, or if the engineer

cannot draw upon some stream of sufficient size, he must form artificial

reservoirs in suitable situations, and the conditions which must be

attended to in selecting the positions of these and in constructing them

are the same as those for drinking-water supply, except that the purity

of the water is not a matter of moment. They must be situated at such an

elevation that the water from them may flow to the summit-level of the

canal, and if the expense of pumping is to be avoided, they must command

a sufficient catchment area to supply the loss of water from the canal

by evaporation from the surface, percolation through the bed, and

lockage. If the supply be inadequate, the draught of the boats plying on

the canal may have to be reduced in a dry season, and the consequent

decrease in the size of their cargoes will both lessen the carrying

capacity of the canal and increase the working expenses in relation to

the tonnage handled. Again, since the consumption of water in lockage

increases both with the size of the locks and the frequency with which

they are used, the difficulty of finding a sufficient water supply may

put a limit to the density of traffic possible on a canal or may

prohibit its locks from being enlarged so as to accommodate boats of the

size necessary for the economical handling of the traffic under modern

conditions. It may be pointed out that the up consumes more water than

the down traffic. An ascending boat on entering a lock displaces a

volume of water equal to its submerged capacity. The water so displaced

flows into the lower reach of the canal, and as the boat passes through

the lock is replaced by water flowing from the upper reach. A descending

boat in the same way displaces a volume of water equal to its submerged

capacity, but in this case the water flows back into the higher reach

where it is retained when the gates are closed.

Waste-weirs and stop-gates.

An essential adjunct to a canal is a sufficient number of waste-weirs to

discharge surplus water accumulating during floods, which, if not

provided with an exit, may overflow the tow-path, and cause a breach in

the banks, stoppage of the traffic, and damage to adjoining lands. The

number and positions of these waste-weirs must depend on the nature of

the country through which the canal passes. Wherever the canal crosses a

stream a waste-weir should be formed in the aqueduct; but independently

of this the engineer must consider at what points large influxes of

water may be apprehended, and must at such places form not only

waste-weirs of sufficient size to carry off the surplus, but also

artificial courses for its discharge into the nearest streams. These

waste-weirs are placed at the top water-level of the canal, so that when

a flood occurs the water flows over them and thus relieves the banks.

Stop-gates are necessary at short intervals of a few miles for the

purpose of dividing the canal into isolated reaches, so that in the

event of a breach the gates may be shut, and the discharge of water

confined to the small reach intercepted between two of them, instead of

extending throughout the whole line of canal. In broad canals these

stop-gates may be formed like the gates of locks, two pairs of gates

being made to shut in opposite directions. In small works they may be

made of thick planks slipped into grooves formed at the narrow points of

the canal under road bridges, or at contractions made at intermediate

points to receive them. Self-acting stop-gates have been tried, but have

not proved trustworthy. When repairs have to be made stop-gates allow of

the water being run off by "off-lets" from a short reach, and afterwards

restored with but little interruption of the traffic. These off-lets are

pipes placed at the level of the bottom of the canal and provided with

valves which can be opened when required. They are generally formed at

aqueducts or bridges crossing rivers, where the contents of the canal

between the stop-gates can be run off into the stream.

Locks.

Locks are chambers, constructed of wood, brickwork, masonry or concrete,

and provided with gates at each end, by the aid of which vessels are

transferred from one reach of the canal to another. To enable a boat to

ascend, the upper gates and the sluices which command the flow of water

from the upper reach are closed. The sluices at the lower end of the

lock are then opened, and when the level of the water in the lock has

fallen to that of the lower reach, the boat passes in to the lock. The

lower gates and sluices being then closed, the upper sluices are opened,

and when the water rising in the lock has floated the boat up the level

of the upper reach the upper gates are opened and it passes out. For a

descending boat the procedure is reversed. The sluices by which the lock

is filled or emptied are carried through the walls in large locks, or

consist of openings in the gates in small ones. The gates are generally

of oak, fitting into recesses of the walls when open, and closing

against sills in the lock bottom when shut. In small narrow locks

single gates only are necessary; in large locks pairs of gates are

required, fitting together at the head or "mitre-post" when closed. The

vertical timber at the end of the gate is known as the "heel-post," and

at its foot is a casting that admits an iron pivot which is fixed in the

lock bottom, and on which the gate turns. Iron straps round the head of

the heel-post are let into the lock-coping to support the gate. The

gates are opened and closed by balance beams projecting over the lock

side, by gearing or in cases where they are very large and heavy by the

direct action of a hydraulic ram. In order to economize water canal

locks are made only a few inches wider than the vessels they have to

accommodate. The English canal boat is about 70 or 75 ft. long and 7 or

8 ft. in beam; canal barges are the same length but 14 or 15 ft. in

width, so that locks which will hold one of them will admit two of the

narrower canal boats side by side. In general canal locks are just long

enough to accommodate the longest vessels using the navigation. In some

cases, however, provision is made for admitting a train of barges; such

long locks have sometimes intermediate gates by which the effective

length is reduced when a single vessel is passing. The lift of canal

locks, that is, the difference between the level of adjoining reaches,

is in general about 8 or 10 ft., but sometimes is as little as 1-1/2 ft.

On the Canal du Centre (Belgium) there are locks with a lift of 17 ft.,

and on the St Denis canal near La Villette basins in Paris there is one

with a lift of 32-1/2 ft. In cases where a considerable difference of

level has to be surmounted the locks are placed close together in a

series or "flight," so that the lower gates of one serve also as the

upper gates of the next below. To save water, expecially where the lift

is considerable, side ponds are sometimes employed; they are reservoirs

into which a portion of the water in a lock-chamber is run, instead of

being discharged into the lower reach, and is afterwards used for

partially filling the chamber again. Double locks, that is, two locks

placed side by side and communicating by a passage which can be opened

or closed at will, also tend to save water, since each serves as a side

pond to the other. The same advantage is gained with double flights of

locks, and time also is saved since vessels can pass up and down

simultaneously.

Inclines.

A still greater economy of water can be effected by the use of inclined

planes or vertical lifts in place of locks. In China rude inclines

appear to have been used at an early date, vessels being carried down a

sloping plane of stonework by the aid of a flush of water or hauled up

it by capstans. On the Bude canal (England) this plan was adopted in an

improved form, the small flat-bottomed boats employed being fitted with

wheels to facilitate their course over the inclines. Another variant,

often adopted as an adjunct to locks where many small pleasure boats

have to be dealt with, is to fit the incline itself with rollers, upon

which the boats travel. In some cases the boats are conveyed on a

wheeled trolley or cradle running on rails; this plan was adopted on the

Morris canal, built in 1825-1831, in the case of 23 inclines having

gradients of about 1 in 10, the rise of each varying from 44 to 100 ft.

Between the Ourcq canal and the Marne, near Meaux, the difference of

level is about 40 ft., and barges weighing about 70 tons are taken from

the one to the other on a wheeled cradle weighing 35 tons by a wire rope

over an incline nearly 500 yards long. But heavy barges are apt to be

strained by being supported on cradles in this way, and to avoid this

objection they are sometimes drawn up the inclines floating in a tank or

caisson filled with water and running on wheels. This arrangement was

utilized about 1840 on the Chard canal (England), and 10 years later it

was adapted at Blackhill on the Monkland canal (Scotland) to replace a

double flight of locks, in consequence of the traffic having been

interrupted by insufficiency of water. There the height to be overcome

was 96 ft. Two pairs of rails, of 7 ft. gauge, were laid down on a

gradient of 1 in 10, and on these ran two carriages having wrought iron,

water-tight caissons with lifting gates at each end, in which the barges

floated partially but not wholly supported by water. The carriages, with

the barge and water, weighed about 80 tons each, and were arranged to

counterbalance each other, one going up as the other was going down. The

power required was provided by two high pressure steam engines of 25

h.p., driving two large drums round which was coiled, in opposite

directions, the 2-inch wire rope that hauled the caissons. An incline

constructed on the Union canal at Foxton (England) to replace 10 locks

giving a total rise of 75 ft., accommodates barges of 70 tons, or two

canal boats of 33 tons. It is in some respects like the Monkland canal

incline, but the movable caissons work on four pairs of rails on an

incline of 1 in 14, broadside on, and the boats are entirely waterborne.

Steam power is employed, with an hydraulic accumulator which enables

hydraulic power to be used in keeping the caisson in position at the top

of the incline while the boats are being moved in or out, a water-tight

joint being maintained with the final portion of the canal during the

operation. The gates in the caisson and canal are also worked by

hydraulic power. The incline is capable of passing 200 canal boats in 12

hours, and the whole plant is worked by three men.

Lifts.

Vertical lifts can only be used instead of locks with advantage at

places where the difference in level occurs in a short length of canal,

since otherwise long embankments or aqueducts would be necessary to

obtain sites for their construction. An early example was built in 1809

at Tardebigge on the Worcester and Birmingham canal. It consisted of a

timber caisson, weighing 64 tons when full of water, counterpoised by

heavy weights carried on timber platforms. The lift of 12 ft. was

effected in about three minutes by two men working winches. Seven lifts,

erected on the Grand Western canal between Wellington and Tiverton about

1835, consisted of two chambers with a masonry pier between them. In

each chamber there worked a timber caisson, suspended at either end of a

chain hung over large pulleys above. As one caisson descended the other

rose, and the apparatus was worked by putting about a ton more water in

the descending caisson than in the ascending one. At Anderton a lift was

erected in 1875 to connect the Weaver navigation with the Trent and

Mersey canal, which at that point is 50 ft. higher than the river. The

lift is a double one, and can deal with barges up to 100 tons. The

change is made while the vessels are floating in 5 ft. of water

contained in a wrought iron caisson, 75 ft. long and 15-1/2 ft. wide. An

hydraulic ram 3 ft. in diameter supports each caisson, the bottom of

which is strengthened so as to transfer the weight to the side girders.

The descending caisson falls owing to being filled with 6 in. greater

depth of water than the ascending one, the weight on the rams (240 tons)

being otherwise constant, since the barge displaces its own weight of

water; an hydraulic accumulator is used to overcome the loss of weight

in the descending caisson when it begins to be immersed in the lower

level of the river. The two presses in which the rams work are connected

by a 5-in. pipe, so that the descent of one caisson effects the raising

of the other. A similar lift, completed in 1888 at Fontinettes on the

Neuffosse canal in France, can accommodate vessels of 250 tons, a total

weight of 785 tons being lifted 43 ft.; and a still larger example on

the Canal du Centre at La Louviere in Belgium has a rise of 50 ft., with

caissons that will admit vessels up to 400 tons, the total weight lifted

amounting to over 1000 tons. This lift, with three others of the same

character, overcomes the rise of 217 ft., which occurs in this canal in

the course of 4-1/3 m.

Animal power.

_Haulage._--The horse or mule walking along a tow-path and drawing or

"tracking" a boat or barge by means of a towing rope, still remains the

typical method of conducting traffic on the smaller canals; on

ship-canals vessels proceed under their own steam or are aided by tugs.

Horse traction is very slow. The maximum speed on a narrow canal is

about 3-1/2 m. an hour, and the average speed, which, of course, depends

largely on the number of locks to be passed through, very much less. It

has been calculated that in England on the average one horse hauls one

narrow canal boat about 2 m. an hour loaded or 3 m. empty, or two narrow

canal boats 1-1/2 m. loaded and 2-1/2 m. empty. Efforts have

accordingly been made not only to quicken the rate of transit, but also

to move heavier loads, thus increasing the carrying capacity of the

waterways. But at speeds exceeding about 3-1/2 m. an hour the "wash" of

the boat begins to cause erosion of the banks, and thus necessitates the

employment of special protective measures, such as building side walls

of masonry or concrete. For a canal of given depth there is a particular

speed at which a boat can be hauled with a smaller expenditure of energy

than at a higher or a lower speed, this maximum being the speed of free

propagation of the primary wave raised by the motion of the boat (see

WAVE). About 1830 when, in the absence of railways, canals could still

aspire to act as carriers of passengers, advantage was taken of this

fact on the Glasgow and Ardrossan canal, and subsequently on some

others, to run fast passenger boats, made lightly of wrought iron and

measuring 60 ft. in length by about 6 ft. in breadth. Provided with two

horses they started at a low speed behind the wave, and then on a given

signal were jerked on the top of the wave, when their speed was

maintained at 7 or 8 m. an hour, the depth of the canal being 3 or 4 ft.

This method, however, is obviously inapplicable to heavy barges, and in

their case improved conditions of transport had to be sought in other

directions.

Mechanical power.

Steam towage was first employed on the Forth and Clyde canal in 1802,

when a tug-boat fitted with steam engines by W. Symington drew two

barges for a distance of 19-1/2 m. in 6 hours in the teeth of a strong

headwind. As a result of this successful experiment it was proposed to

employ steam tugs on the Bridgewater canal; but the project fell through

owing to the death of the duke of Bridgewater, and the directors of the

Forth and Clyde canal also decided against this method because they

feared damage to the banks. Steam tugs are only practicable on

navigations on which there are either no locks or they are large enough

to admit the tug and its train of barges simultaneously; otherwise the

advantages are more than counterbalanced by the delays at locks. On the

Bridgewater canal, which has an average width of 50 ft. with a depth of

5-1/2 ft., is provided with vertical stone walls in place of sloping

banks, and has no locks for its entire length of 40 m. except at

Runcorn, where it joins the Mersey, tugs of 50 i.h.p., with a draught of

4 ft., tow four barges, each weighing 60 tons, at a rate of nearly 3 m.

an hour. On the Aire and Calder navigation, where the locks have a

minimum length of 215 ft., a large coal traffic is carried in trains of

boat-compartments on a system designed by W.H. Bartholomew. The boats

are nearly square in shape, except the leading one which has an ordinary

bow; they are coupled together by knuckle-joints fitted into hollow

stern-posts, so that they can move both laterally and vertically, and a

wire rope in tension on each side enables the train to be steered. No

boat crews are required, the crew of the steamer regulating the train.

If the number of boats does not exceed 11 they can be pushed, but beyond

that number they are towed. Each compartment carries 35 tons, and the

total weight in a train varies from 700 to 900 tons. On the arrival of a

train at Goole the boats are detached and are taken over submerged

cradles under hydraulic hoists which lift the boat with the cradle

sufficiently high to enable it to be turned over and discharge the whole

cargo at once into a shoot and thence into sea-going steamers. Another

method of utilizing steam-power, which was also first tried on the Forth

and Clyde canal by Symington in 1789, is to provide each vessel with a

separate steam engine, and many barges are now running fitted in this

way. Experiments have also been made with internal combustion engines in

place of steam engines. In some cases, chiefly on rivers having a strong

current, recourse has been had to a submerged chain passed round a drum

on a tug: this drum is rotated by steam power and thus the tug is hauled

up against the current. To obviate the inconvenience of passing several

turns of the chain round the drum in order to get sufficient grip, the

plan was introduced on the Seine and Oise in 1893 of passing the chain

round a pulley which could be magnetized at will, the necessary

adhesion being thus obtained by the magnetic attraction exercised on

the iron chain; and it was also adopted about the same time in

combination with electrical haulage on a small portion of the Bourgogne

canal, electricity being employed to drive the motor that worked the

pulley. Small locomotives running on rails along the towpath were tried

on the Shropshire Union canal, where they were abandoned on account of

practical difficulties in working, and also on certain canals in France

and Germany, where, however, the financial results were not

satisfactory. On portions of the Teltow canal, joining the Havel and the

Spree, electrical tractors run on rails along both banks, taking their

power from an overhead wire; they attain a speed of 2-1/2 m. an hour

when hauling two 600-ton barges. The electrical supply is also utilized

for working the lock gates and for various other purposes along the

route of the canal. In the Mont-de-Rilly tunnel, at the summit level of

the Aisne-Marne canal, a system of cable-traction was established in

1894, the boats being taken through by being attached to an endless

travelling wire rope supported by pulleys on the towpath.

When railways were being carried out in England some canal companies

were alarmed for their future, and sold their canals to the railway

companies, who in 1906 owned 1138 m. of canals out of a total length

in the United Kingdom of 3901 m. As some of these canals are links in

the chain of internal water communication complaints have frequently

arisen on the question of through traffic and tolls. The great

improvements carried out in America and on the continent of Europe by

state aid enable manufacturers to get the raw material they use and

goods they export to and from their ports at much cheaper rates than

those charged on British canals. The association of chambers of

commerce and other bodies having taken up the matter, a royal

commission was appointed in 1906 to report on the canals and

water-ways of the kingdom, with a view to considering how they could

be more profitably used for national purposes. Its Report was

published in December 1909.

AUTHORITIES.--L.F. Vernon-Harcourt, _Rivers and Canals_ (2nd ed.,

1896); Chapman, _Canal Navigation_; Firisi, _On Canals_; R. Fulton,

_Canal Navigation_; Tatham, _Economy of Inland Navigation_; Valancy,

_Treatise on Inland Navigation_; D. Stevenson, _Canal and River

Engineering_; John Phillips, _History of Inland Navigation_; J.

Priestley, _History of Navigable Rivers, Canals, &c. in Great Britain_

(1831); T. Telford, _Life_ (1838); John Smeaton, _Reports_ (1837);

_Reports of the International Congresses on Interior Navigation_;

_Report and Evidence of the Royal Commission on Canals_ (_Great

Britain_), 1906-9. (E. L. W.)

CANAL DOVER, a city of Tuscarawas county, Ohio, U.S.A., on the

Tuscarawas river, about 70 m. S. by E. of Cleveland. Pop. (1890) 3470;

(1900) 5422 (930 foreign-born); (1910) 6621. It is served by the

Baltimore & Ohio and the Pennsylvania railways, and by the Ohio canal,

and is connected with Cleveland by an inter-urban electric line. It lies

on a plateau about 880 ft. above sea-level and commands pleasant views

of diversified scenery. Coal and iron ore abound in the vicinity, and

the city manufactures iron, steel, tin plate, electrical and telephone

supplies, shovels, boilers, leather, flour, brick and tile, salt,

furniture and several kinds of vehicles. The municipality owns and

operates its water-works. Canal Dover was laid out as a town in 1807,

and was incorporated as a village in 1842, but its charter was soon

allowed to lapse and was not revived until 1867. Canal Dover became a

city under the Ohio municipal code of 1903.

CANALE (or CANALETTO), ANTONIO (1697-1768), Venetian painter, born on

the 18th of October 1697, was educated under his father Bernard, a

scene-painter of Venice, and for some time followed his father's line of

art. In 1719 he went to Rome, where he employed himself chiefly in

delineating ancient ruins, and particularly studied effects of light and

shade, in which he became an adept. He was the first painter who made

practical use of the camera lucida. On returning home he devoted his

powers to views in his native city, which he painted with a clear and

firm touch and the most facile mastery of colour in a deep tone,

introducing groups of figures with much effect. In his latter days he

resided some time in England. His pictures, in their particular range,

still remain unrivalled for their magnificent perspective. The National

Gallery, London, has five pictures by him, notably the "View on the

Grand Canal, Venice," and the "Regatta on the Grand Canal." He died on

the 20th of August 1768. Bellotto (commonly named Bernardo), who is also

sometimes called CANALETTO (1724-1780), was his nephew and pupil, and

painted with deceptive resemblance to the style of the more celebrated

master.

CANALIS (also "canal" and "channel"; from the Latin), in architecture,

the sinking between the fillets of the volute of the Ionic capital: in

the earliest examples, though sunk below the fillets, it is slightly

convex in section.

CANANDAIGUA, a village and the county-seat of Ontario county, New York,

U.S.A., 30 m. S.E. of Rochester. Pop. (1890) 5868; (1900) 6151; (1910)

7217. It is served by the New York Central and Hudson River, and the

Northern Central (Pennsylvania system) railways, and is connected with

Rochester by an inter-urban electric line. Among the manufactures are

pressed bricks, tile, beer, ploughs, flour, agate and tin-ware. The

village, picturesquely situated at the north end of Canandaigua Lake, a

beautiful sheet of water about 15 m. long with a breadth varying from a

mile to a mile and a half, is a summer resort. It has a county court

house; the Canandaigua hospital of physicians and surgeons; the

Frederick Ferris Thompson memorial hospital, with a bacteriological

laboratory supported by the county; the Clark Manor House (a county home

for the aged), given by Mrs Frederick Ferris Thompson in memory of her

mother and of her father, Myron Holley Clark (1806-1892), president of

the village of Canandaigua in 1850-1851 and governor of New York in

1855-1857; the Ontario Orphan Asylum; Canandaigua Academy; Granger Place

school for girls; Brigham Hall (a private sanatorium for nervous and

mental diseases); Young Men's Christian Association building (1905); and

two libraries, the Wood (public) library and the Union School library,

founded in 1795. There is a public playground in the village with free

instruction by a physical director; and a swimming school, endowed by

Mrs F.F. Thompson, gives free lessons in swimming. The village owns its

water-supply system. A village of the Seneca Indians, near the present

Canandaigua, bearing the same name, which means "a settlement was

formerly there" (not, as Lewis Morgan thought, "chosen spot"), was

destroyed by Gen. John Sullivan in 1779. There are boulder memorials of

Sullivan's expedition and of the treaty signed here on the 11th of

November 1794 by Timothy Pickering, on behalf of the United States with

the Six Nations--a treaty never ratified by the Senate. Canandaigua was

settled in 1789 and was first incorporated in 1812.

CANARD (the Fr. for "duck"), a sensational or extravagant story, a hoax

or false report, especially one circulated by newspapers. This use of

the word in France dates from the 17th century, and is supposed by

Littre to have originated in the old expression, "_vendre un canard a

moitie_" (to half-sell a duck); as it is impossible to "half-sell a

duck," the phrase came to signify to take in, or to cheat.

CANARY (_Serinus canarius_), a well-known species of passerine bird,

belonging to the family _Fringillidae_ or finches (see FINCH). It is a

native of the Canary Islands and Madeira, where it occurs abundantly in

the wild state, and is of a greyish-brown colour, slightly varied with

brighter hues, although never attaining the beautiful plumage of the

domestic bird. It was first domesticated in Italy during the 16th

century, and soon spread over Europe, where it is now the most common of

cage-birds. During the years of its domestication, the canary has been

the subject of careful artificial selection, the result being the

production of a bird differing widely in the colour of its plumage, and

in a few of its varieties even in size and form, from the original wild

species. The prevailing colour of the most admired varieties of the

canary is yellow, approaching in some cases to orange, and in others to

white; while the most robust birds are those which, in the dusky green

of the upper surface of their plumage, show a distinct approach to the

wild forms. The least prized are those in which the plumage is

irregularly spotted and speckled. In one of the most esteemed varieties,

the wing and tail feathers are at first black--a peculiarity, however,

which disappears after the first moulting. Size and form have also been

modified by domestication, the wild canary being not more than 5-1/2 in.

in length, while a well-known Belgian variety usually measures 8 in.

There are also hooped or bowed canaries, feather-footed forms and

top-knots, the latter having a distinct crest on the head; but the

offspring of two such top-knotted canaries, instead of showing an

increased development of crest, as might be expected, are apt to be bald

on the crown. Most of the varieties, however, of which no fewer than

twenty-seven were recognized by French breeders so early as the

beginning of the 18th century, differ merely in the colour and the

markings of the plumage. Hybrids are also common, the canary breeding

freely with the siskin, goldfinch, citril, greenfinch and linnet. The

hybrids thus produced are almost invariably sterile. It is the female

canary which is almost invariably employed in crossing, as it is

difficult to get the females of the allied species to sit on the

artificial nest used by breeders. In a state of nature canaries pair,

but under domestication the male bird has been rendered polygamous,

being often put with four or five females; still he is said to show a

distinct preference for the female with which he was first mated. It is

from the others, however, that the best birds are usually obtained. The

canary is very prolific, producing eggs, not exceeding six in number,

three or four times a year; and in a state of nature it is said to breed

still oftener. The work of building the nest, and of incubation, falls

chiefly on the female, while the duty of feeding the young rests mainly

with the cock bird. The natural song of the canary is loud and clear;

and in their native groves the males, especially during the pairing

season, pour forth their song with such ardour as sometimes to burst the

delicate vessels of the throat. The males appear to compete with each

other in the brilliancy of their melody, in order to attract the

females, which, according to the German naturalist Johann Matthaus

Bechstein (1757-1822) always select the best singers for their mates.

The canary readily imitates the notes of other birds, and in Germany and

especially Tirol, where the breeding of canaries gives employment to a

large number of people, they are usually placed for this purpose beside

the nightingale. (A. N.)

CANARY ISLANDS (_Canarias_), a Spanish archipelago in the Atlantic

Ocean; about 60 m. W. of the African coast, between 27 deg. 40' and 29

deg. 30' N., and between 13 deg. 20' and 18 deg. 10' W. Pop. (1900)

358,564; area 2807 sq. m. The Canary Islands resemble a roughly-drawn

semicircle, with its convex side facing south-wards, and with the island

of Hierro detached on the south-west. More precisely, they may be

considered as two groups, one of which, including Teneriffe, Grand

Canary, Palma, Hierro and Gomera, consists of mountain peaks, isolated

and rising directly from an ocean of great depth; while the other,

comprising Lanzarote, Fuerteventura and six uninhabited islets, is based

on a single submarine plateau, of far less depth. Teneriffe and Gomera,

the only members of the principal group which have a common base, may be

regarded as the twin peaks of one great volcanic mass. Ever since the

researches of Leopold von Buch the Canary Islands have been classical

ground to the student of volcanic action. Buch considered them to be

representative of his "craters of elevation." In common with the other

West African islands they are of volcanic origin. The lavas consist

chiefly of trachytes and basalts.

[Illustration: CANARY ISLANDS MAP]

_Climate_.--From April to October a north or north-east wind blows upon

the islands, beginning about 10 A.M. and continuing until 5 or 6 P.M. In

summer this wind produces a dense stratum of sea-cloud (_cumuloni_), 500

ft. thick, whose lower surface is about 2500 ft. above the sea at

Teneriffe. This does not reach up to the mountains, which have on every

side a stratum of their own, about 1000 ft. thick, the lower surface

being about 3500 ft. above the level of the sea. Between these two

distinct strata there is a gap, through which persons on a vessel near

the island may obtain a glimpse of the peak. The sea-cloud conceals from

view the other islands, except those whose mountains pierce through it.

On the south-west coasts there is no regular sea or land breeze. In

winter they are occasionally visited by a hot south-east wind from

Africa, which is called the _Levante_, and produces various disagreeable

consequences on the exposed parts of the person, besides injuring the

vegetation, especially on the higher grounds. Locusts have sometimes

been brought by this wind. In 1812 it is said that locusts covered some

fields in Fuerteventura to the depth of 4 ft. Hurricanes, accompanied by

waterspouts, sometimes cause much devastation; but, on the whole, the

islands are singularly free from such visitations. The climate generally

is mild, dry and healthy. On the lower grounds the temperature is

equable, the daily range seldom exceeding 6 deg. Fahr. At Santa Cruz the

mean for the year is about 71 deg. The rainy season occurs at the same

period as in southern Europe. The dry season is at the time of the

trade-winds, which extend a few degrees farther north than this

latitude.

_Fauna_.--The indigenous mammals of the Canary Islands are very few in

number. The dog, swine, goat and sheep were alone found upon the island

by the Spanish conquerors: The race of large dogs which is supposed to

have given a name to the islands has been long extinct. A single

skeleton has been found, which is deposited in one of the museums at

Paris. The ferret, rabbit, cat, rat, mouse and two kinds of bat have

become naturalized. The ornithology is more interesting, on account at

once of the birds native to the islands, and the stragglers from the

African coast, which are chiefly brought over in winter, when the wind

has blown for some time from the east. Among the indigenous birds are

some birds of prey, as the African vulture, the falcon, the buzzard, the

sparrow-hawk and the kite. There are also two species of owl, three

species of sea-mew, the stockdove, quail, raven, magpie, chaffinch,

goldfinch, blackcap, canary, titmouse, blackbird, house-swallow, &c. As

to the insects, mention may be made of a species of gnat or mosquito

which is sometimes troublesome, especially to strangers. The list of

reptiles is limited to three varieties of lizard and one species of

frog. The only fresh-water fish is the eel. Marine fishes are not

numerous, the reason perhaps being that the steepness of the coast does

not allow seaweed to grow in sufficient quantity to support the lower

forms of marine animal life. Whales and seals are occasionally seen. The

cuttle-fish is abundant, and is sought for as an article of food.

_Flora_.--The position of mountainous islands like the Canaries, in the

subtropical division of the temperate zone, is highly favourable to the

development, within a small space, of plants characteristic of both warm

and cold climates. Von Buch refers to five regions of vegetation in

Teneriffe:--(1) From the sea to the height of 1300 ft. This he styles

the African region. The climate in the hottest parts is similar to that

of Egypt. Here grow, among the introduced plants, the coffee tree, the

date-palm, the sugar-cane, the banana, the orange tree, the American

agave and two species of cactus; and among indigenous plants, the dragon

tree on the north-west of Teneriffe. A leafless and fantastic euphorbia,

_E. canariensis_, and a shrubby composite plant, _Cacalia kleinia_, give

a character to the landscape about Santa Cruz. (2) Between 1300 ft. and

2800 ft. This is the region of south European vegetation, the climate

answering to that of southern France and central Italy. Here nourish

vines and cereals. (3) The region of indigenous trees, including

various species of laurel, an _Ardisia, Ilex, Rhamnus, Olea, Myrica_,

and other trees found wild also at Madeira. The clouds rest on this

region during the day, and by their humidity support a vegetation

amongst the trees, partly of shrubs, and partly of ferns. It extends to

the height of 4000 ft. (4) The region of the beautiful _Pinus

canariensis_, extending to the height of 6400 ft.; here the broad-leaved

trees have ceased to grow, but arborescent heaths are found throughout

its whole extent, and specimens of _Juniperus oxycedrus_ may be met

with. (5) The region of Retama (_Cytisus nubigenus_), a species of

white-flowering and sweet-scented broom, which is found as high as

11,000 ft. At the upper edge of this region a lilac-coloured violet

clings to the soil, and above there is nothing but a little lichen. The

number of wild flowering plants may be estimated at 900, upwards of 270

of which are peculiar to the Canaries. The forms of vegetation must in

the main be considered North African. The character of the vegetation in

Lanzarote and Fuerteventura, islands composed of extensive plains and

low hills, with few springs, is different from that of the other

islands, which are more elevated and have many springs. The wood is less

abundant, and the vegetation less luxuriant.

_Inhabitants_.--The Guanches (q.v.), who occupied the Canaries at the

time of the Spanish invasion, no longer exist as a separate race, for

the majority were exterminated, and the remainder intermarried with

their conquerors. The present inhabitants are slightly darker than the

people of Spain, but in other respects are scarcely distinguishable from

them. The men are of middle height, well-made and strong; the women are

not striking in respect of beauty, but they have good eyes and hair.

Spanish is the only language in use. The birth-rate is uniformly high

and the death-rate low; and, despite the emigration of many families to

South America and the United States, the census of 1900 showed that the

population had increased by over 75,000 since 1877. The excess of

females over males, which in 1900 amounted to upwards of 22,000, is

partly explained by the fact that few women emigrate. Fully 80% of the

inhabitants could neither read nor write in 1900; but education

progresses more rapidly than in many other Spanish provinces. Good

schools are numerous, and the return of emigrants and their children who

have been educated in the United States, tends to raise the standard of

civilization. The sustenance of the poorer classes is chiefly composed

of fish, potatoes and _gofio_, which is merely Indian corn or wheat

roasted, ground and kneaded with water or milk. The land is, in great

part, strictly entailed.

_Government_.--The archipelago forms one Spanish province, of which the

capital is Santa Cruz de Tenerife, the residence of the civil governor,

who has under his command one of the two districts into which the

archipelago is divided, this first district comprising Teneriffe, Palma,

Gomera and Hierro. The other district includes Grand Canary, Lanzarote,

Fuerteventura, and has at its head a sub-governor, residing in Las

Palmas, on Grand Canary, who is independent of the governor except in

regard to elections and municipal administration. The chief finance

office is at Santa Cruz de Tenerife. The court of appeal, created in

1526, is in Las Palmas. The captain-general and second commandant of the

archipelago reside in Santa Cruz de Tenerife, and there is a

brigadier-governor of Grand Canary, residing in Las Palmas, besides

eight inferior military commandants. The province furnishes no men for

the Spanish peninsular army, but its annual conscription provides men

for the local territorial militia, composed of regiments of infantry,

squadrons of mounted rifles and companies of garrison artillery--about

5000 men all told. The archipelago is divided into two naval districts,

commanded by royal navy captains. Roman Catholicism is the official

religion, and ecclesiastical law is the same as in other Spanish

provinces. The convents have been suppressed, and in many cases

converted to secular uses. Laguna and Las Palmas are episcopal sees, in

the archbishopric of Seville.

_Industry and Commerce._--Owing to the richness of the volcanic soil,

agriculture in the Canaries is usually very profitable. Land varies in

value according to the amount of water available, but as a rule commands

an extraordinarily high price. In the _Terrenos de secano_, or

non-irrigable districts, the average price of an acre ranges from L7 to

L17; in the _Terrenes de riego_, or irrigable land, it ranges from L100

to L250. Until 1853 wine was the staple product, and although even the

finest brand (known as _Vidonia_) never equalled the best Madeira

vintages, it was largely consumed abroad, especially in England. The

annual value of the wine exported often exceeded L500,000. In 1853,

however, the grape disease attacked the vineyards; and thenceforward the

production of cochineal, which had been introduced in 1825, took the

place of viticulture so completely that, twenty years later, the exports

of cochineal were worth L556,000. France and England were the chief

purchasers. This industry declined in the later years of the 19th

century, and was supplanted by the cultivation of sugar-cane, and

afterwards of bananas, tomatoes, potatoes and onions. Bananas are the

most important crop. Other fruits grown in smaller quantities include

oranges, figs, dates, pineapples, guavas, custard-apples and prickly

pears. Tobacco-planting is encouraged by the Spanish government, and the

sugar trade is maintained, despite severe competition. The grain harvest

does not supply the needs of the islanders. Pigs and sheep of a small,

coarse-woolled breed, are numerous; and large herds of goats wander in

an almost wild state over the higher hills. Fishing is a very important

industry, employing over 10,000 hands. The fleet of about 2200 boats

operates along some 600 m. of the African coast, between Cape Cantin and

the Arguin Bank. Shipbuilding is carried on at Las Palmas; and the minor

industries include the manufacture of cloth, drawn-linen (_calado_)

work, silk, baskets, hats, &c. A group of Indian merchants, who employ

coolie labour, produce silken, jute and cotton goods, Oriental

embroideries, wrought silver, brass-ware, porcelain, carved sandal-wood,

&c. The United Kingdom heads the import trade in coal, textiles,

hardware, iron, soap, candles and colonial products. Timber comes

chiefly from North America and Scandinavia, alcohol from Cuba and the

United States, wheat and flour from various British possessions, maize

from Morocco and Argentina. Large quantities of miscellaneous imports

are sent by Germany, Spain, France and Italy. Bananas, tomatoes,

potatoes, sugar and wine are exported. The total value of the foreign

trade fluctuates very greatly, and the difficulty of forming an estimate

is enhanced in many years by the absence of official statistics; but

imports and exports together probably amount in a normal year to about

L1,000,000. The chief ports are Las Palmas and Santa Cruz, which

annually accommodate about 7000 vessels of over 8,000,000 tons. In 1854

all the ports of the Canaries were practically declared free; but on the

1st of November 1904 a royal order prohibited foreign vessels from

trading between one island and another. This decree deprived the

outlying islands of their usual means of communication, and, in answer

to a protest by the inhabitants, its operation was postponed.

_History_.--There is ground for supposing that the Phoenicians were not

ignorant of the Canaries. The Romans learned of their existence through

Juba, king of Mauretania, whose account of an expedition to the islands,

made about 40 B.C., was preserved by the elder Pliny. He mentions

"Canaria, so called from the multitude of dogs of great size," and

"Nivaria, taking its name from perpetual snow, and covered with clouds,"

doubtless Teneriffe. Canaria was said to abound in palms and pine trees.

Both Plutarch and Ptolemy speak of the Fortunate Islands, but from their

description it is not clear whether the Canaries or one of the other

island groups in the western Atlantic are meant; see ISLES OF THE BLEST.

In the 12th century the Canaries were visited by Arab navigators, and in

1334 they were rediscovered by a French vessel driven among them by a

gale. A Portuguese expedition, undertaken about the same time, failed to

find the archipelago, and want of means frustrated the project of

conquest entertained by a grandson of Alphonso X. of Castile, named Juan

de la Cerda, who had obtained a grant of the islands and had been

crowned king of them at Avignon, by Pope Clement VI. Two or possibly

more Spanish expeditions followed, and a monastic mission was

established, but at the close of the 14th century the Guanches remained

unconquered and unconverted. In 1402, however, Gadifer de la Salle and

Jean de Bethencourt (q.v.) sailed with two vessels from Rochelle, and

landed early in July on Lanzarote. The relations between these two

leaders, and their respective shares in the work of conquest and

exploration, have been the subject of much controversy. Between 1402 and

1404 La Salle conquered Lanzarote and part of Fuerteventura, besides

exploring other islands; Bethencourt meanwhile sailed to Cadiz for

reinforcements. He returned in 1404 with the title of king, which he had

secured from Henry III. of Castile. La Salle, thus placed in a position

of inferiority, left the islands and appealed unsuccessfully for redress

at the court of Castile. In 1405 Bethencourt visited Normandy, and

returned with fresh colonists who conquered Hierro. In December 1406 he

left the Canaries, entrusting their government to his nephew Maciot de

Bethencourt, and reserving for himself a share in any profits obtained,

and the royal title. Eight years of misrule followed before Queen

Catherine of Castile intervened. Maciot thereupon sold his office to her

envoy, Pedro Barba de Campos; sailed to Lisbon and resold it to Prince

Henry the Navigator; and a few years afterwards resold it once more to

Enrique de Guzman, count of Niebla. Jean de Bethencourt, who died in

1422, bequeathed the islands to his brother Reynaud; Guzman sold them to

another Spaniard named Paraza, who was forced to re-sell to Ferdinand

and Isabella of Castile in 1476; and Prince Henry twice endeavoured to

enforce his own claims. Meanwhile the Guanches remained unconquered

throughout the greater part of the archipelago. In 1479 the sovereignty

of Ferdinand and Isabella over the Canaries was established by the

treaty of Alcacova, between Portugal and Castile. After much bloodshed,

and with reinforcements from the mother country, the Spaniards, under

Pedro de Vera, became masters of Grand Canary in 1483. Palma was

conquered in 1491, and Teneriffe in 1495, by Alonzo de Lugo. The

archipelago was included for administrative purposes in the

captaincy-general of Andalusia until 1833, when it was made a separate

province. In 1902 a movement in favour of local autonomy was repressed

by Spanish troops.

BIBLIOGRAPHY.--For a general description of the islands, see _Les Iles

Canaries_, by J. Pitard and L. Proust (Paris, 1909); _Madeira and the

Canary Islands_, by A. Samler Brown, a guide for travellers and

invalids, with coloured maps and plates (London, 1901); _A Guide to

the Canary Islands_, by J.H.T. Ellerbeck (London, 1892); _The Canary

Islands as a Winter Resort_, by J. Whitford (London, 1890, with maps

and illustrations); _De la Tierra Canaria_, by L. and A. Millares

Cubas (Madrid, 1894); and _Physikalische Beschreibung der kanarischen

Inseln_, by L. von Buch (Berlin, 1825). Besides the interesting folio

atlas of von Buch (Paris, 1836), good modern maps have been published

by E. Stanford (London, 1891, 12-1/2 English m. to 1 in.), and M.

Perez y Rodriquez (Madrid, 1896-1898, 4 sheets). See also _Histoire

naturelle des iles Canaries_, by P. Barker-Webb and S. Berthelot

(Paris, 1835-1849); and "Les Iles Canaries et les parages de peche

canariens," by Dr. A. Taquin, in the _B.S.R. Beige G. 26_ (1902), and

27 (1903); and, for history and antiquities, the _Historia general de

las islas Canarias_, by A. Millares Cubas, in 10 vols. (Las Palmas,

1893-1895),and _Historia de la Inquisicion en las islas Canarias_, by

the same author (Las Palmas, 1874); _Antiquites canariennes_, by S.

Berthelot (Paris, 1879).

CANCALE, a fishing port of north-western France in the department of

Ille-et-Vilaine on the Bay of Cancale, 9 m. E.N.E. of St Malo by road.

Pop. (1906) town 3827, commune 7061. It exports oysters, which are found

in its bay in large numbers and of excellent quality, and equips a fleet

for the Newfoundland cod-fisheries. The harbour is protected by the

rocks known as the Rochers de Cancale. In 1758 an English army under the

duke of Marlborough landed here for the purpose of attacking St Malo and

pillaged the town. It was again bombarded by the English in 1779.

CANCEL (from the Lat. _cancelli_, a plural diminutive of _cancer_, a

grating or lattice, from which are also derived "chancel" and

"chancellor"), a word meaning to cross out, from the crossed latticed

lines drawn across a legal document to annul it, hence to delete or

destroy.

CANCELLI (plural of Lat. _cancellus_, dim. of _cancer_, a crossing bar),

in architecture, the term given to barriers which correspond to the

modern balustrade or railing, especially the screen dividing the body of

a church from the part occupied by the ministers; hence "chancel"

(q.v.). By the Romans _cancelli_ were similarly employed to divide off

portions of the courts of law (cf. the English "bar").

CANCER, LUIS (d. 1549), Spanish missionary to Central America, was born

at Barbastro near Saragossa. After working for some time in Dominica and

Haiti, he crossed to the mainland, where he had great success in

pacifying the Indians whom more violent methods had failed to subdue. He

upheld the cause of the natives at an ecclesiastical assembly held in

Mexico in 1546, and three years later, on the 26th of June, met his

death at their hands on the west coast of Florida.

CANCER ("THE CRAB"), in astronomy, the fourth sign of the zodiac,

denoted by the symbol [Crab symbol]. Its name may be possibly derived

from the fact that when the sun arrives at this part of the ecliptic it

apparently retraces its path, resembling in some manner the sidelong

motion of a crab. It is also a constellation, mentioned by Eudoxus (4th

century B.C.) and Aratus (3rd century B.C.); Ptolemy catalogued 13 stars

in it, Tycho Brahe 15 and Hevelius 29. Its most interesting objects are:

a large loose cluster of stars, known as _Praesepe_ or the Beehive,

visible as a nebulous patch to the naked eye, and [zeta] _Cancri_, a

remarkable multiple star, composed of two stars, of magnitudes 5 and

5.7, revolving about each other in 60 years, and a third star of

magnitude 5.5 which revolves about these two in an opposite direction in

a period of 17-1/2 years; from irregularities in the motion of this star,

it is supposed to be a satellite of an invisible body which itself

revolves about the two stars previously mentioned, in a period of 600 to

700 years.

CANCER, or CARCINOMA (from Lat. _cancer_, Gr. _[Greek: karkiuoma]_, an

eating ulcer), the name given to a class of morbid growths or tumours

which occur in man, and also in most or all vertebrate animals. The term

"malignant disease" is commonly used as synonymous with "cancer." For

the general pathology, &c., of tumours see TUMOUR.

Cancer exists in various forms, which, although differing from each

other in many points, have yet certain common characters to which they

owe their special significance.

1. In structure such growths are composed of nucleated cells and free

nuclei together with a milky fluid called cancer juice, all contained

within a more or less dense fibrous stroma or framework.

2. They have no well-defined limits, and they involve all textures in

their vicinity, while they also tend to spread by the lymphatics and

veins, and to cause similar growths in distant parts or organs called

"secondary cancerous growths."

3. They are undergoing constant increase, and their progress is usually

rapid.

4. Pain is a frequent symptom. When present it is generally of a severe

and agonizing character, and together with the local effects of the

disease and the resulting condition of ill health or "cachexia," hastens

the fatal termination to which all cancerous growths tend.

5. When such growths are removed by the surgeon they are apt to return

either at the same or at some other part.

The chief varieties of cancer are _Scirrhus_ or hard cancer,

_Encephaloid_ or soft cancer and _Epithelial cancer_.

Scirrhus is remarkable for its hardness, which is due to the large

amount of its fibrous, and relatively small proportion of its cell

elements. It is of comparatively slow growth, but it tends to spread and

to ulcerate. Its most common seat by far is the female breast, though it

sometimes affects internal organs.

Encephaloid is in structure the reverse of the last, its softness

depending on the preponderance of its cell over its fibrous elements.

Its appearance and consistence resemble brain substance (hence its

name), and it is of such rapid growth as to have given rise to its being

occasionally termed _acute cancer_. Its most frequent seats are

internal organs or the limbs. Ulceration and haemorrhage are common

accompaniments of this form of cancer.

Epithelial cancer is largely composed of cells resembling the natural

epithelium of the body. It occurs most frequently in those parts

provided with epithelium, such as the skin and mucous membranes, or

where those adjoin, as in the lips. This form of cancer does not spread

so rapidly nor produce secondary growths in other organs to the same

extent as the two other varieties, but it tends equally with them to

involve the neighbouring lymphatic glands, and to recur after removal.

Cancer affects all parts of the body, but is much more frequent in some

tissues than in others. According to recent statistics prepared by the

registrar-general for England and Wales (sixty-seventh annual report)

the most frequent seats are, in numerical order, as

follows:--_males_--stomach, liver, rectum, intestines, aesophagus,

tongue; _females_--uterus, breast, stomach, liver, intestines, rectum.

Other statistics give similar, though not identical results. It may be

said, broadly, that the most frequent seats are the female sexual organs

and after them the digestive tract in both sexes. In children, in whom

cancer is rare, the most frequent seats appear to be--under five, the

kidneys and supra-renal bodies; five to ten, the brain; ten to twenty,

the arm and leg bones.

Cancer tends to advance steadily to a fatal termination, but its

duration varies in different cases according to the part affected and

according to the variety of the disease. Soft cancer affecting important

organs of the body often proves fatal in a few months, while, on the

other hand, cases of hard or epithelial cancer may sometimes last for

several years; but no precise limit can be assigned for any form of the

disease. In some rare instances growths exhibiting all the signs of

cancer may exist for a great length of time without making any progress,

and may even dwindle and disappear altogether. This is called

"spontaneous cure."

Cancer research.

Cancer has been the subject of observation from time immemorial, and of

the most elaborate investigation by innumerable workers in recent years;

but the problems of its origin and character have hitherto baffled

inquiry. Modern scientific study of them may be said to have begun with

J. Muller's microscopic work in the structure of cancerous tissue early

in the 19th century. A great impetus to this line of investigation was

given by the cellular theory of R. Virchow and the pathological

researches of Sir J. Paget, and general attention was directed to the

microscopic examination of the cells of which cancer is composed. This

led to a classification, on which much reliance was once placed, of

different kinds of cancer, based on the character of the cells, and

particularly to a distinction between _carcinoma_, in which the cells

are of the epithelial type, and _sarcoma_, in which they are of the

connective tissue type. The distinction, though still maintained, has

proved barren; it never had any real significance, either clinical or

pathological, and the tendency in recent research is to ignore it. The

increased knowledge gained in numerous other branches of biological

science has also been brought to bear on the problem of cancer and has

led to a number of theories; and at the same time the apparently

increasing prevalence of the disease recorded by the vital statistics of

many countries has drawn more and more public attention to it. Two

results have followed. One is the establishment of special endowed

institutions devoted to cancer research; the other is the publication

and discussion of innumerable theories and proposed methods of

treatment. Popular interest has been constantly fanned by the

announcement of some pretended discovery or cure, in which the public is

invited to place its trust. Such announcements have no scientific value

whatever. In the rare cases in which they are not pure quackery, they

are always premature and based on inadequate data.

Organized cancer research stands on a different footing. It may be

regarded as the revival at the end of the 19th century of what was

unsuccessfully attempted at the beginning. As early as 1792, at the

suggestion of Mr. John Howard, surgeon, a ward was opened at the

Middlesex hospital in London for the special benefit of persons

suffering from cancer. It was fitted up and endowed anonymously by Mr.

Samuel Whitbread, M.P. for Bedford, and according to the terms of the

benefaction at least six patients were to be continually maintained in

it until relieved by art or released by death. The purpose was both

philanthropic and scientific, as Mr. Howard explained in bringing

forward the suggestion. Two principal objects, he said, presented

themselves to his mind, "namely, the relief of persons suffering under

this disease and the investigation of a complaint which, although

extremely common, is both with regard to its natural history and cure

but imperfectly known." This benefaction was the origin of one of the

most complete institutions for the scientific study of cancer that

exists to-day.

In 1804 a Society for Investigating the Nature of Cancer was formed by a

number of medical men in London, Edinburgh and other towns at the

instigation of John Hunter. The aim was collective investigation, and an

attempt was made to carry it out by issuing forms of inquiry; but the

imperfect means of communication then existing caused the scheme to be

abandoned in a short time. Subsequent attempts at collective

investigation also failed until recently. About 1900 a movement, which

had been for some time gathering force, began to take visible shape

simultaneously in different countries. The cancer ward at the Middlesex

hospital had then developed into a cancer wing, and to it were added

special laboratories for the investigation of cancer, which were opened

on the 1st of March 1900. In this establishment the fully equipped means

of clinical and laboratory research were united under one roof and

manned by a staff of investigators under the direction of Dr W.S.

Lazarus Barlow. In the same year the _Deutsche Comite fur

Krebsforschung_ was organized in Berlin, receiving an annual subsidy of

5000 marks (L250) from the imperial exchequer. This body devoted its

energies to making a census of cancer patients in Germany on a definite

date. A special ward for cancer was also set apart at the Charite

hospital in Berlin, with a state endowment of 53,000 marks (L2560) per

annum, and a laboratory for cancer research was attached to the first

medical clinique under Professor Ernst von Leyden at the same hospital.

A third institution in Germany is a special cancer department at the

Royal Prussian Institute for Experimental Therapeutics at

Frankfort-on-Main, which has been supported, like the Imperial Cancer

Research Fund in England, by private contributions on a generous scale.

The fund just mentioned was initiated in October 1901, and its

operations took definite shape a year later, when Dr. E.F. Bashford was

appointed general superintendent of research. The patron of the

foundation was King Edward VII., and the president was the prince of

Wales. It had in 1908 a capital endowment of about L120,000, subscribed

by private munificence and producing an income of about L7000 a year.

The central laboratory is situated in the examination building of the

Royal Colleges of Physicians and Surgeons in London, and the work is

conducted under the superintendence of an executive committee formed by

representatives of those bodies. In the United States a cancer

laboratory, which had been established in Buffalo in 1899 under Dr

Roswell Park, was formally placed under the control of New York state in

June 1901, and is supported by an annual grant of $15,000 (L3000). There

are other provisions in the United States connected with Harvard and

Cornell universities. At the former the "Caroline Brewer Croft Fund for

Cancer Research" started special investigations in the surgical

department of the Harvard Medical School in 1900 or the previous year,

and in connexion with the Cornell University Medical School there is a

small endowment called the "Huntingdon Cancer Research Fund." There

appear to be institutions of a similar character in other countries, in

addition to innumerable investigators at universities and other ordinary

seats of scientific research.

Some attempt has been made to co-ordinate the work thus carried on in

different countries. An international cancer congress was held at

Heidelberg and Frankfort in 1906, and a proposal was put forward by

German representatives that a permanent international conference on

cancer should be established, with headquarters in Berlin. The committee

of the Imperial Cancer Research Fund did not fall in with the proposal,

being of opinion that more was to be gained in the existing stage of

knowledge by individual intercourse and exchange of material between

actual laboratory workers.

Theories of cancer.

In spite of the immense concentration of effort indicated by the

simultaneous establishment of so many centres of endowed research, and

in spite of the light thrown upon the problem from many sides by modern

biological science, our knowledge of the origin of cancer is still in

such a tentative state that a detailed account of the theories put

forward is not called for; it will suffice to indicate their general

drift. The actual pathological process of cancer is extremely simple.

Certain cells, which are apparently of a normal character and have

previously performed normal functions, begin to grow and multiply in an

abnormal way in some part of the body. They continue this process so

persistently that they first invade and then destroy the surrounding

tissues; nothing can withstand their march. They are moreover carried to

other parts of the body, where they establish themselves and grow in the

same way. Their activity is carried on with relentless determination,

though at a varying pace, until the patient dies, unless they are bodily

removed. Hence the word "malignant." The problem is--what are these

cells, or why do they behave in this way? The principal answers put

forward may be summarized:--(1) they are epithelial cells which grow

without ceasing because the connective tissue has lost the capacity to

hold their proliferative powers in check (H. Freund, following K.

Thiersch and W. Waldeyer); (2) they are embryonic cells accidentally

shut off (J.F. Cohnheim); (3) they are epithelial cells with a latent

power of unlimited proliferation which becomes active on their being

dislocated from the normal association (M.W.H. Ribbert and Borrmann);

(4) they are stimulated to unlimited growth by the presence of a

parasite (Plimmer, Sanfelice, Roncali and others); (5) they are

fragments of reproductive tissue (G.T. Beatson); (6) they are cells

which have lost their differentiated character and assumed elementary

properties (von Hausemann, O. Hertwig). The very number and variety of

hypotheses show that none is established. Most of them attempt to

explain the growth but not the origin of the disease. The hypothesis of

a parasitic origin, suggested by recent discoveries in relation to other

diseases, has attracted much attention; but the observed phenomena of

cancerous growths are not in keeping with those of all known parasitic

diseases, and the theory is now somewhat discredited. A more recent

theory that cancer is due to failure of the normal secretions of the

pancreas has not met with much acceptance.

Some generalizations bearing on the problem have been drawn from the

work done in the laboratories of the Imperial Cancer Research Fund. They

may be summarily stated thus. Cancer has been shown to be an identical

process in all vertebrates (including fishes), and to develop at a time

which conforms in a striking manner to the limits imposed by the long or

short compass of life in different animals. Cancerous tissue can be

artificially propagated in the short-lived mouse by actual transference

to another individual, but only to one of the same species. Cancerous

tissue thus propagated presents all the characteristic features of the

malignant growth of sporadic tumours; it infiltrates and produces

extensive secondary growths. Under suitable experimental conditions the

aggregate growth of a cancer is undefined, of enormous and, so far as we

can judge, of limitless amount. This extraordinary growth is due to the

continued proliferation of cancerous cells when transplanted. The

processes by which growing cancer cells are transferred to a new

individual are easily distinguishable and fundamentally different from

all known processes of infection. The artificial propagation of cancer

causes no specific symptoms of illness in the animal in which it

proceeds. Under artificial propagation cancer maintains all the

characters of the original tumours of the primary hosts. _Carcinoma_ and

_sarcoma_ agree in possessing all the pathological and cellular

features of malignant new growths.

Statistics of cancer.

Simultaneously with the active pursuit of laboratory research much

statistical work has been devoted to establishing the broad facts of the

prevalence and incidence of cancer on a firm basis. The point of most

general interest is the apparently steady increase of the disease in all

countries possessing fairly trustworthy records. It will be sufficient

to give the figures for England and Wales as an example.

ANNUAL DEATH-RATES FROM CANCER TO A MILLION LIVING. _England and

Wales._

+----------+----------+----------+----------+----------+----------+----------+

|1871-1875.|1876-1880.|1881-1885.|1886-1890.|1891-1895.|1896-1900.|1901-1904.|

+----------+----------+----------+----------+----------+----------+----------+

| 445 | 493 | 547 | 631 | 711 | 800 | 861 |

+----------+----------+----------+----------+----------+----------+----------+

In forty years the recorded rate had risen from 403 to 861. The question

how far these and similar statistics represent a real increase cannot be

satisfactorily resolved, because it is impossible to ascertain how much

of the apparent increase is due to more accurate diagnosis and improved

registration. Some of it is certainly due to those causes, so that the

recorded figures cannot be taken to represent the facts as they stand.

At the same time it is certain that some increase has taken place in

consequence of the increased average length of life; a larger proportion

of persons now reach the ages at which cancer is most frequent. Increase

due to this fact, though it is a real increase, does not indicate that

the cause of cancer is more rife or more potent; it only means that the

condition of the population in regard to age is more favourable to its

activity. On the whole it seems probable that, when allowance has been

made for this factor and for errors due to improved registration, a real

increase due to other causes has taken place, though it is not so great

as the recorded statistics would indicate.

The long-established conclusions concerning the incidence of the disease

in regard to age and sex have been confirmed and rendered more precise

by modern statistics. Cancer is a disease of old age; the incidence at

the ages of sixty-five to seventy-five is ten times greater than at the

ages thirty-five to forty-five. This fact is the source of frequent

fallacies when different countries or districts and different periods

are compared with each other, unless account is taken of the differences

in age and constitution. With regard to sex females are far more liable

than males; the respective death-rates per million living for England

and Wales in 1904 were--males 740; females 1006. But the two rates show

a tendency to approximate; the increase shown over a series of years has

been considerably more rapid among males than among females. One result

of more careful examination of statistics has been to discredit, though

perhaps somewhat hastily, certain observations regarding the prevalence

of cancer in special districts and special houses. On the other hand the

fuller statistics now available concerning the relative frequency of

cancer in the several organs and parts of the body, of which some

account is given above, go to confirm the old observation that cancer

commonly begins at the seat of some local irritation. By far the most

frequent seats of disease are the uterus and breast in women and the

digestive tract in both sexes, and these are all particularly subject to

such irritation. With regard to the influence of heredity the trend of

modern research is to minimize or deny its importance in cancer, as in

phthisis, and to explain family histories by other considerations. At

most heredity is only thought to confer a predisposition.

Treatment.

The only "cure" for cancer remains removal by operation; but improved

methods of diagnosis enable this to be done in many cases at an earlier

stage of the disease than formerly; and modern methods of surgery permit

not only of operation in parts of the body formerly inaccessible, but

also more complete removal of the affected tissues. Numerous forms of

treatment by modern therapeutic means, both internal and external, have

been advocated and tried; but they are all of an experimental nature and

have failed to meet with general acceptance. One of the most recent is

treatment by trypsin, a pancreatic ferment. This has been suggested by

Dr John Beard of Edinburgh in conformity with the theory, mentioned

above, that failure of the pancreatic secretions is the cause of cancer.

It has been claimed that the drug exercises a favourable influence in

conjunction with operation and even without it. The experience of

different observers with regard to results is contradictory; but

clinical investigations conducted at Middlesex hospital in a number of

cases of undoubted cancer in strict accordance with Dr Beard's

directions, and summarized by Dr Walter Ball and Dr Fairfield Thomas in

the _Sixth Report from the Cancer Research Laboratories_ (_Archives of

Middlesex Hospital_, vol. ix.) in May 1907, resulted in the conclusion

"that the course of cancer, considered both as a disease and as a morbid

process, is unaltered by the administration of trypsin and amylopsin."

The same conclusion has been reached after similar trials at the cancer

hospital. Another experimental method of treatment which has attracted

much attention is application of the X-rays. The results vary in a

capricious and inexplicable manner; in some cases marked benefit has

followed, in others the disease has been as markedly aggravated. Until

more is known both of cancer and of X-rays, their use must be considered

not only experimental but risky. (A. Sl.)

CANCRIN, FRANZ LUDWIG VON (1738-1812), German mineralogist and

metallurgist, was born on the 21st of February 1738, at Breitenbach,

Hesse-Darmstadt. In 1764 he entered the service of the landgrave of

Hesse-Darmstadt at Hanau, becoming professor of mathematics at the

military academy, head of the civil engineering department of the state,

director of the theatre and (1774) of the mint. A work on the copper

mines of Hesse (1767) earned him a European reputation, and in 1783 he

accepted from Catherine II. of Russia the directorship of the famous

Staraya salt-works, living thenceforth in Russia. In 1798 he became a

councillor of state at St Petersburg. He published many works on

mineralogy and metallurgy, of which the most important, the _Grundzuge

der Berg- und Salzwerkskunde_ (13 vols., Frankfort, 1773-1791), has been

translated into several languages. His son, Count Georg von Cancrin, or

Kankrin (1774-1845), was the eminent Russian minister of finance.

CANDELABRUM (from Lat. _candela_, a taper or candle), the stand on which

ancient lamps were placed. The most ancient example is the bronze

candelabrum made by Callimachus for the Erechtheum at Athens, to carry

the lamp sacred to Minerva. In this case it is probable the lamp was

suspended, as in the example from Pompeii, now in the Naples museum;

this consisted of a stalk or reed, the upper part moulded with

projecting feature to carry the lamps, and a base resting on three

lions' or griffins' feet; sometimes there was a disk at the top to carry

a lamp, and sometimes there was a hollow cup, in which resinous woods

were burnt. The origin of the term suggests that on the top of the disk

was a spike to carry a wax or tallow candle (_candela_ or _funalia_).

Besides these bronze candelabra, of which there are many varieties in

museums, the Romans used more ponderous supports in stone or marble, of

which many examples were found in the Thermae. These consisted of a

base, often triangular, and of similar design to the small sacrificial

altars, and a shaft either richly moulded or carved with the acanthus

plant and crowned with a large cup or basin. There is a fine example of

the latter in the Vatican. The Roman examples seem to have served as

models for many of the candelabra in the churches in Italy. The word

"candelabrum" is also now used to describe many different forms of

lighting with multiple points, and is often applied to hanging lights as

well as to those which rise from a stand.

CANDIA, formerly the capital and still the most populous city of Crete

(q.v.), to which it has given its name. It is situated on the northern

shore somewhat nearer the eastern than the western end of the island, in

35 deg. 20' N. lat. and 25 deg. 9' E. long. It is still surrounded by its

extensive Venetian fortifications; but they have fallen into disrepair,

and a good part of the town is in a dilapidated condition, mainly from

the effects of earthquakes. The principal buildings are the Venetian

loggia (barbarously mutilated by the new regime), the Konak (now

Prefecture), the mosques, which are fourteen in number, the new

cathedral, the two Greek churches, the Armenian church, the Capuchine

monastery, the bazaars and the baths. There are also some beautiful

Venetian fountains. The town is the seat of a Greek archbishop. A highly

interesting museum has been formed here containing the antiquities found

during the recent excavations. The chief trade is in oil and soap, both

of which are of excellent quality. The coasting trade, which is of

considerable importance, is mainly carried on in Turkish vessels. The

manufacture of leather for home consumption is an extensive industry and

wine of good quality is produced in the neighbourhood. The harbour,

which had grown almost inaccessible, was deepened by Mustapha Pasha

between 1820 and 1840. It is formed for the most part by the ancient

moles, and was never deep enough to admit the larger vessels even of the

Venetians, which were accustomed to anchor in the port of the

neighbouring island of Standia. A short distance from St George's Gate

there was a small village exclusively inhabited by lepers, who numbered

about seventy families, but they have now been transported to

Spinalonga. The population of the town is estimated at from 15,000 to

18,000, about half being Mahommedan Greeks. The site of Candia, or, as

it was till lately locally known, Megalo castro (the Great Fortress),

has been supposed to correspond with that of the ancient _Heracleion_,

the seaport of Cnossus, and this appellation has now been officially

revived by its Greek inhabitants. The ruins of Cnossus are situated at

the distance of about 3 m. to the south-east at the village of

Makryteichos or Long Wall. Founded by the Saracens in the 9th century,

Candia was fortified by the Genoese in the 12th, and was greatly

extended and strengthened by the Venetians in the 13th, 14th and 15th

centuries. It was besieged by the Turks under the vizier Achmet in 1667;

and, in spite of a most heroic defence, in which the Venetians lost

30,000 in killed and wounded, it was forced to surrender in 1669. (See

also CRETE.)

CANDIDATE, one who offers himself or is selected by others for an office

or place, particularly one who puts up for election to parliament or to

any public body. The word is derived from the Latin _candidatus_, clad

in white (_candidus_). In Rome, candidates for election to the higher

magistracies appeared in the Campus Martius, the Forum and other public

places, during their canvass, in togas with the white of the natural

wool brightened by chalk.

CANDLE (Lat. _candela_, from _candere_, to glow), a cylindrical rod of

solid fatty or waxy matter, enclosing a central fibrous wick, and

designed to be burnt for giving light. The oldest materials employed for

making candles are beeswax and tallow, while among those of more recent

introduction are spermaceti, stearine and paraffin wax. Waxlights

(_cereus_, sc. _funis_) were known to the Romans. In the midlde ages wax

candles were little used, owing to their expense, except for the

ceremonies of the church and other religious purposes (see LIGHTS,

CEREMONIAL USE OF), but in the 15th century, with the cheapening of wax,

they began to find wider employment. The tallow candle, mentioned by

Apuleius as _sebaceus_, was long an article of domestic manufacture. The

tallow was melted and strained, and then lengths of cotton or flax

fibre, or rushes from which most of the external skin had been stripped,

only sufficient being left to support the pith ("rushlights"), were

dipped into it, the operation being repeated until the desired thickness

had been attained. In Paris, in the 13th century, there was a gild of

candlemakers who went from house to house to make tallow candles, the

manufacture of wax candles being in the hands of another gild. This

separation of the two branches of the trade is also exemplified by the

existence of two distinct livery companies in the city of London--the

Waxchandlers and the Tallowchandlers; the French _chandelle_ properly

means tallow candle, candles made of materials less fusible than tallow

being called _bougies_, a term said to be derived from the town of

Bougie in Algeria, either because wax was produced there or because the

Venetians imported wax candles thence into Europe. The old tallow "dips"

gave a poor light, and tallow itself is now used only to a limited

extent, except as a source of "stearine." This is the trade name for a

mixture of solid fatty acids--mainly stearic and palmitic--manufactured

not only from tallow and other animal fats, but also from such vegetable

fats as palm-oil. Paraffin wax, a mixture of solid hydrocarbons obtained

from crude North American and Rangoon petroleum, and also yielded in

large quantities by the Scotch shale oil industry, is, at least in Great

Britain, a still more important material of candle-manufacture, which

came into use about 1854. Spermaceti, a crystalline fatty substance

obtained from the sperm whale (_Physeter macrocephalus_), was introduced

as a material for candles about a century earlier. In practice the

candlemaker mostly uses mixtures of these materials. For instance, 5-10%

of stearine, which is used alone for candles that have to be burnt in

hot climates, is mixed with paraffin wax, to counteract the tendency to

bend with heat exhibited by the latter substance. Again, the brittleness

of spermaceti is corrected by the addition of beeswax, stearine,

paraffin wax or ceresin (obtained from the mineral wax ozocerite). In

some "composite" candles stearine is mixed with the hard fat ("cocoa-nut

stearine") expressed from cocoa-nut oil by hydraulic pressure; and this

cocoa-nut stearine is also used for night-lights, which are short thick

candles with a thin wick, calculated to burn from six to ten hours.

The stearine or stearic acid industry originated in the discovery made

by M.E. Chevreul about 1815, that fats are glycerides or compounds of

glycerin with fatty acids, mostly palmitic, stearic and oleic. The

object of the candlemaker is to remove this glycerin, not only because

it is a valuable product in itself, but also because it is an

objectionable constituent of a candle; the vapours of acrolein formed by

its decomposition in the flame are the cause of the unpleasant odours

produced by tallow "dips." He also removes the oleic acid, which is

liquid at ordinary temperatures, from the palmitic and stearic acids,

mixtures of which solidify at temperatures varying from about 130 deg.

to 155 deg. F., according to the percentage of each present. Several

methods are in use for the decomposition of the fats. In the autoclave

process the fat, whether tallow, palm-oil or a mixture of the two, mixed

with 25 or 30% of water and about 3% of lime, is subjected in an

autoclave to steam at a pressure of about 120 lb per square inch for

eight or ten hours, when nearly all of it is saponified. On standing the

product separates into two layers--"sweet water" containing glycerin

below, and the fatty acids with a certain amount of lime soap above. The

upper layer is then boiled and treated with enough sulphuric acid to

decompose the lime soap, the calcium sulphate formed is allowed to

subside, and the fatty acids are run off into shallow boxes to be

crystallized or "seeded" prior to the separation of the oleic acid,

which is effected by pressing the solid blocks from the boxes, first

cold and then hot, by hydraulic machinery. In another process

saponification is effected by means of concentrated sulphuric acid. The

fat is mixed with 4-6% of the acid and treated with steam in boiling

water till the hydrolysis is complete, when on standing the glycerin and

sulphuric acid sink to the bottom and the fatty acids rise to the top.

Owing to the darkness of their colour, when this process is employed,

the latter usually have to be distilled before being crystallized. The

autoclave process yields about 45% of stearine, one-third of which is

recovered from the expressed oleic acid, but with sulphuric acid

saponification the amount of stearine is higher--over 60%--and that of

oleic acid less, part of it being converted into solid material by the

action of the acid. The yield of glycerin is also less. In a combination

of the two processes the fat may first be treated by the autoclave

process, so as to obtain a full yield (about 10%) of glycerin, and the

resulting fatty acids then subjected to acid saponification, so as to

get the higher amount of stearine. At the best, however, some 30% of

oleic acid remains, and though often sought, no satisfactory method of

converting this residue into solid has been discovered. It constitutes

"red oil," and is used in soap-making and in woollen manufacture. In the

process patented by Ernst Twitchell in 1898, decomposition is effected

by boiling the fat with half its bulk of water in presence of a reagent

obtained by the action of sulphuric acid on oleic acid and an aromatic

hydrocarbon such as benzene.

The wick is a most important part of a candle, and unless it is of

proper size and texture either too much or too little fuel will be

supplied to the flame, and the candle will gutter or be otherwise

unsatisfactory. The material generally employed is cotton yarn, plaited

or "braided" by machinery, and treated or "pickled" with a solution of

boracic acid, ammonium or potassium nitrate, or other salt. The

tightness of the plaiting varies with the material used for the candle,

wicks for stearine being looser than for paraffin, but tighter than for

wax or spermaceti. The plaited wick is flat and curls over as the candle

burns, and thus the end is kept projecting into the outer part of the

flame where it is consumed, complete combustion being aided by the

pickling process it has undergone. In the old tallow dips the strands of

cotton were merely twisted together, instead of being plaited; wicks

made in this way had no determinate bias towards the outside of the

flame, and thus were not wholly consumed, the result being that there

was apt to be an accumulation of charred matter, which choked the flame

unless removed by periodical "snuffing."

Four ways of making candles may be distinguished--dipping, pouring,

drawing and moulding, the last being that most commonly employed.

_Dipping_ is essentially the same as the domestic process already

described, but the rate of production is increased by mounting a number

of wicks in a series of frames, each of which in turn is brought over

the tallow bath so that its wicks can be dipped. _Pouring_, used in the

case of wax, which cannot well be moulded because it contracts in

cooling and also has a tendency to stick to the moulds, consists in

ladling molten wax upon the wicks suspended from an iron ring. When of

the desired thickness the candles are rolled under a plate on a marble

slab. In _drawing_, used for small tapers, the wick, rolled on a drum,

is passed through the molten wax or paraffin, drawn through a circular

hole and slowly wound on a second drum; it is then passed again through

the molten material and through a somewhat larger hole, and reeled back

on the first drum, this process being repeated with larger and larger

holes until the coating is of the required thickness. In _moulding_, a

number of slightly conical moulds are fixed by the larger extremity to a

kind of trough, with their tapered ends projecting downwards and with

wicks arranged down their centres. The molten material is poured into

the trough and fills the moulds, from which the candles are withdrawn

when solidified. Modern candle-moulding machines are continuous in their

operation; long lengths of wick are coiled on bobbins, one for each

mould, and the act of removing one set of candles from their moulds

draws in a fresh set of wicks. "Self-fitting ends," which were invented

by J.L. Field in 1864, and being shaped like a truncated cone enable the

candles to be fixed in candlesticks of any diameter, are formed by means

of an attachment to the tops of the moulds; spirally twisted candles

are, as it were, unscrewed from their moulds. It is necessary to be able

to regulate the temperature of the moulds accurately, else the candles

will not come out freely and will not be of good appearance. For

stearine candles the moulds are immersed in tepid water and the cooling

must be slow, else the material will crystallize, though if it be too

slow cracking will occur. For paraffin, on the other hand, the moulds

must be rather hotter than the molten material (about 200 deg. F.), and

must be quickly cooled to prevent the candles from sticking.

A candle-power, as a unit of light in photometry, was defined by the

(London) Metropolis Gas Act of 1860 as the light given by a sperm

candle, of which six weighed 1 lb and each burned 120 grains an hour.

See W. Lant Carpenter, _Soaps and Candles_ (London, 1895); C.E. Groves

and W. Thorp, _Chemical Technology_, vol. ii. "Lighting" (London,

1895); L.L. Lamborn, _Soaps, Candles and Glycerine_ (New York, 1906);

J. Lewkowitsch, _Oils, Fats, and Waxes_ (London, 1909).

CANDLEMAS (Lat. _festum candelarum sive luminum_), the name for the

ancient church festival, celebrated annually on the 2nd of February, in

commemoration of the presentation of Christ in the Temple. In the Greek

Church it is known as [Greek: Upapante tou Kuriou] ("the meeting of the

Lord," i.e. with Simeon and Anna), in the West as the Purification of

the Blessed Virgin. It is the most ancient of all the festivals in

honour of the Virgin Mary. A description is given of its celebration at

Jerusalem in the _Peregrinatio_ of Etheria (Silvia), in the second half

of the 4th century. It was then kept on the 14th of February, forty days

after Epiphany, the celebration of the Nativity (Christmas) not having

been as yet introduced; the Armenians still keep it on this day, as "the

Coming of the Son of God into the Temple." The celebration gradually

spread to other parts of the church, being moved to the 2nd of February,

forty days after the newly established feast of Christmas. In 542 it was

established throughout the entire East Roman empire by Justinian. Its

introduction in the West is somewhat obscure. The 8th-century _Gelasian

Sacramentary_, which embodies a much older tradition, mentions it under

the title of Purification of the Blessed Virgin Mary, which has led some

to suppose that it was ordained by Pope Gelasius I. in 492[1] as a

counter-attraction to the heathen Lupercalia; but for this there is no

warrant. The procession on this day was introduced by Pope Sergius I.

(687-701). The custom of blessing the candles for the whole year on this

day, whence the name Candlemas is derived, did not come into common use

until the 11th century.

In the _Quadragesimae de Epiphania_ as described by Etheria there is, as

Monsignor Duchesne points out (_Christian Worship_, p. 272), no

indication of a special association with the Blessed Virgin; and the

distinction between the festival as celebrated in the East and West is

that in the former it is a festival of Christ, in the latter a festival

pre-eminently of the Virgin Mother.

See L. Duchesne, _Christian Worship_ (Eng. trans., London, 1904); art.

s.v. by F.G. Holweck in the _Catholic Encyclopaedia_.