substituting for these prayer, and preserved every thing that came spontaneously from God, as dreams, visions, and prophetic inspirations. Perhaps the feelings that lay at the heart of the faith in the ancient divination helped unconsciously to prepare the human mind for the Christian belief in providence, in the efficacy of prayer, and in a special revelation of God to man. respected by the ancient Romans, and is still practised by the Malays and Polynesians. Somewhat similar to it is scapulomancy, the method of divining by the cracks and lines made in a shoulderblade placed in the fire. Palmistry, or cheiromancy, has still its thousands of votaries and its own literature, and is warmly defended by those who fail to see how childish is the sham symbolism, and how Many of the most ancient forms of artificial entirely arbitrary are all the analogies on which it divination have survived to our own day, even in is based. Other methods of divining again may the heart of our vaunted modern civilisation. The depend on the more or less conscious action of the sense of the efficacy of these methods undoubtedly agent. Such is the planchette, by means of which depends on the association of ideas in supposed answers in writing are given; but the most famous analogies, and in symbolism. The Samoan rain- form in this kind is the divining-rod, with its supdoctors wet a stone when they want rain, and dry posed power of indicating a hidden spring of water, it at the fire when they want dry weather; and a vein of ore, or a buried treasure (rhabdomancy). sorcerers all the world over bring harm upon their For these, see AUTOMATIC WRITING, PLANCHETTE, victim by wishing it strongly, or by prophesying and DIVINING - ROD. Of the same nature are that it will happen, as well as by symbolically the ancient coscinomancy, with a hanging sieve and representing it in some simple act, as by torturing shears, and the ordeal of the key, both highly useful a wax-model or the like. There is an elemental where a culprit was apt to betray himself by his confusion between the subjective and the objective fears. Other of the thousand forms of divination connection which the primitive mind is unable to are bibliomancy, by opening at random the Old distinguish. It cannot resist the conviction that or New Testament, or such popular books as the association in thought involves similar connection works of Homer or Virgil; crystallomancy, by lookin reality. The analogies are not consciously ing into a crystal or beryl to see the future reprearbitrary, but admit fairly of ratiocination if we sented directly in pictures, or symbolically by can get into the proper mental attitude to commence figures capable of being interpreted; geomancy, by the chain. Rousseau's conviction of his salvation the observation of points or lines on the earth, or or damnation from his hitting or missing a tree on paper; pyromancy, by the behaviour of fire; with a stone is based upon a mental process natural and botanomancy, from the chance combinations enough to the primitive mind. Added to this is made by the wind upon leaves of trees on which the belief in the direct agency of supernatural words and questions had been written. Of profound powers which influence the casting of lots or the significance also are the barking of dogs, the fall to tossing of a coin, now a mere mechanical appeal to the right or left hand of stones or sticks flung blind chance, but once a solemn attempt to educe upwards, the behaviour of a ring hung over a cup at the divine will. Early grave ideas of supernatural the approach of particular persons, the spots on the interference with games of chance linger long in folk-finger-nails, the physiognomy of the persons met lore, and we still turn our chair to change our luck by chance at critical periods, the blowing off the at dice or cards, and attach absurd importance to seeds of the dandelion, or the pulling off the petals certain numbers for lottery-tickets. The Mora of the daisy with certain time-honoured formulas vian Brethren even chose their wives by sortilege repeated the while. Countless omens are derived or casting lots with prayer, just as the Hebrew by means of hemp sown at midsummer, by nuts patriarchs did at grave or doubtful junctures three burned before a fire, from certain appearances of thousand years ago. The ancient Greek kottabos, green ivy leaves, willow-wands, and the like; while by which fortune in love was discovered by the those who are observant of the proper rites may particular splash made by wine thrown out of a ward off ill-luck, and force the future to their concup into a metal basin; the astragali, or knuckle- venience, with the sign of the cross, and the use bones of the Romans, used for divination and as of the horseshoe, silver, or the holly. The future dice; the Polynesian divination by spinning the is often foretold also by apparitions, and these are niu or coconut to see if a sick person will recover; not infrequently, as in the classical case of the witch and the playing-cards by means of which Gypsies of Endor, capable of being called forth for the purstill read fortunes at English fairs (cartomancy), pose of prophesying by powerful sorcerers. are enough to show the great variety in range of methods of divining. Many of these have been gravely formulated and systematised into pseudosciences. Thus astrology was not only one of the most serious studies of the ancient Chaldæans, but was still more than respectable in the time of New ton; augury by the sight and cries of birds alone gave employment to a whole college of officials in ancient Rome; and the ordeal by fire or battle had the most solemn sanction of the medieval Christian church. Many of the notions lingering in folklore about the hearing of certain birds on the right or the left hand, or the meaning attached to first meeting certain animals or people and the like, may be understood by symbolism; but many more are now at least completely inexplicable and hopelessly confusing. Dreams to animistic thinkers are directly due to spiritual intercourse, and their symbolical interpretation (oneiromancy), either as taken directly or by the equally valid method of contraries, has been practised from the days of Joseph until now, and has given rise to a rich crop of folklore superstitions everywhere. Divination by the appearance of entrails, or haruspication, was much | Divination is founded on faith, but has often also been helped by fraud. It is a sincere although fallacious philosophy, and finds its strongest support in the fancied proofs of its truth that strike the minds of a primitive people, who forget or overlook the misses in their eagerness to verify the hits. The persistent tendency to believe what one wishes to believe, and the inherent human craving for mysteries and wonders, account for any belief. "The human understanding,' says Bacon, when any proposition has been once laid down (either from general admission and belief, or from the pleasure it affords), forces everything else to add fresh support and confirmation; and although most cogent and abundant instances may exist to the contrary, yet either does not observe or despises them, or gets rid of and rejects them by some distinction, with violent and injurious prejudice, rather than sacrifice the authority of its first conclusions.' See the articles APPARITION, ASTROLOGY, AUGURIES, ORACLES, ORDEAL, MAGIC, MYSTICISM, PALMISTRY, and CHARMS, DEMONOLOGY, DIVINING-ROD, DREAM, OMENS, SORTES VIRGILIANE; also Bouché-Leclerq's Histoire de la Divination dans l'Antiquité (4 vols. 1879-82); Halliday's Greek Divination (1913). 1620 Lord Bacon in his Novum Organum describes the crude method in vogue in his day, in which no means of replenishing the air were employed. Towards the close of the 17th century, many attempts were made, and much capital sunk in submarine exploration, but the primitive nature of the apparatus employed rendered the various enterprises undertaken abortive. Dr Halley's divingbell, about 1720, was a wooden chamber of about 60 feet internal capacity, open at the bottom, where it was loaded with lead, to keep it perpenset in the upper part, to admit light. Casks filled with air, and loaded with lead, were let down with the bung-hole downwards; and from these a supply of air was drawn by means of a hose. John Lethbridge, about the same time, constructed a conical bell, into which he forced compressed air by means of bellows, enabling him to remain over half an hour beneath the surface. In 1754 Dr Richard Pococke saw a diving-bell used at the Needles to raise what they could of the wreck of a man-of-war. They are let down in a machine made of leather, strengthened at the knees and shoulders, and, if I mistake not, on the head, with brass. There are two leathern tubes to it--one for the air to go down and to speak by, the other to pump out the air. They stay down five minutes' (Travels through England, Camden Soc. 1889). In 1779 Smeaton employed an oblong box supplied with air by means of a pump on the surface, for repairing the bridge at Hexham, in Northumberland. Divine Right, a term applied to describe the source of the power claimed for the monarch, by the royalist party, in the great controversies between the monarchical and parliamentary or commonwealth parties in England in the 17th century. The monarch was held to be the immediate representative of the Deity, to whom alone he was responsible for all his actions—a principle which relieved him from all human responsibility, and gave him an absolute claim to the obedience of his subjects. Two of the confessions of Henry VIII.'s reign-the Institution and Necessary Doctrine-dicular in its descent. Strong pieces of glass were both insist on the duty of passive obedience as a corollary of the fifth commandment; and Cranmer so altered the coronation oath at the accession of Edward VI., as to make the king's hereditary right wholly independent of election or the will of the people. But the doctrine became full fledged only after the quiet transfer of the crown from the Tudor to the Stewart dynasty showed that the hereditary principle was firmly established; and James I. constantly harped on the necessity of this great principle. The chief writers on the side of divine right were Salmasius and Sir Robert Filmer; on the other, Milton, Algernon Sidney, and Har rington. The controversy died a natural death after the accession of the Hanoverian dynasty. The miraculous power claimed by English sovereigns of curing the 'king's evil' (see SCROFULA) by the royal touch, was a consequence of their divine right. See J. N. Figgis, Divine Right (2d ed. 1914). Diving. The treasures of the deep' have at all times been the subject of much visionary exaggeration, and the accounts of the exploits of divers equally extravagant. Thus, it is sometimes affirmed that the pearl-divers of the East acquire by practice the power of remaining under water from 15 to 20 minutes, or even two hours. It need scarcely be said that these accounts are absurd, no such endurance being possible. The more skilful divers may remain under water for 2 or even 3 minutes; and 4 minutes 29 seconds is claimed to have been attained in a glass tank (see PEARL). Most divers suffer severely from the continual efforts in holding the breath; bloodshot eyes and spitting of blood are common among them. It is noteworthy that if one about to dive breathes hard for a short time, he is then able to hold his breath much longer under water (see SWIMMING). The rude mode of diving is now but little used except for pearl and sponge fishing. Even for these purposes the diving apparatus is now largely used, the diver thus collecting, it is computed, as much as twenty naked divers under the old primitive regime, and being able to remain from two to four hours under water. In the Mediterranean sponge-fisheries, hundreds of sets of diving apparatus have long been in use, and the dress has been introduced into the fisheries at the Bahamas, Bermuda, Australia, &c. The form of diving-bell now in use was first constructed by Smeaton for work at Ramsgate, in 1788. It was of cast-iron, and weighed 50 cwt., its height 4 feet, length the same, and width 3 feet. It sunk by its own weight, and was lighted by stout pieces of bull's-eye glass, firmly cemented in brass rings near the top. The next improvement of importance was that due to Rennie, who designed in 1813, for the works of Ramsgate Harbour, a diving-bell of cast-iron, 6 feet high, 4 feet 6 inches wide, and 6 feet long. Six bull'seyes of glass in the top admitted light. Air was admitted through the top by a valve, and was supplied by an air-pump through a 23-inch hose. The interior of the bell was fitted with seats, chains for attaching stones, &c., and a rail for carrying tools. The bell, which weighed about 5 tons, was suspended by stout chains to a crab fixed to a truck travelling on an overhead gantry, and was successfully employed in various undertakings carried out by its designer. Access is gained to some large diving-bells by means of a wrought-iron shaft and Air-lock (q.v.), whereby the necessity of raising the bell is obviated. This apparatus has been both efficient and economical in working. The air-chambers of the caissons used for founding the piers of bridges are nothing more than huge DIVING-BELL.-For all such purposes as sub- diving bells, only they remain in position when aqueous works upon the foundations of piers, sunk to the requisite depth, and are filled up solid bridges, &c., or the exploration and raising of with masonry (see CAISSON). At the St Louis sunken vessels, the efforts of the unaided diver Bridge across the Mississippi the maximum depth would be almost valueless, and, accordingly, vari- attained was 110 feet, and the greatest pressure ous contrivances for supplying air to the diver 51 lb., a pressure which proved fatal in a few have been made. Roger Bacon (1240) is said, on instances to the workmen. The air-chambers of most doubtful authority, to have invented a the caissons of the Forth Bridge were 70 feet in machine for working under water. Taisnier's diameter, and 7 feet high. The work of excavadescription of the cacabus aquaticus, or aquatic tion was carried on by electric light, and presented kettle, used by two Greeks in Spain, at Toledo in a singularly novel and weird spectacle. 1538, in the presence of the Emperor Charles V. maximum pressure was about 33 lb. per sq. inch and a multitude of spectators, is one of the earabove the atmosphere. The altered conditions of liest reliable accounts of a diving-bell. From his existence under a pressure of three atmospheres description, this must have been similar in prin- presents many points of interest. The voice ciple and construction to the modern diving sounds unnatural, and as if proceeding from bell, but of clumsy dimensions, and wanting in another person; whistling is impossible. Efferefficient means of renewing the supply of air. Invescing drinks open flat, the pressure outside being The equal to that accumulated in them. A feeling of lassitude is generally experienced on return to ordinary atmospheric conditions. The passage through the air-lock on entering, and the gradual admission of pressure, is at times, and more especially to novices, accompanied by severe pains in the ears; but with due care, and the observance of the prescribed simple expedients, these pass away. Under increased air-pressure the blood dissolves a considerable quantity of atmospheric nitrogen, which in the diving-bell remains dissolved just as does the gas in aerated waters. When the pressure is released it is liberated in bubbles in the bloodvessels, and produces the symptoms of 'caisson-disease.' The principle of the diving-bell will be easily understood by floating a piece of lighted candle or a wax match on a cork, and then covering it with an inverted tumbler, and pressing it downwards; the candle will descend below the level of the surrounding water, and continue burning for a short time, although the tumbler be entirely immersed. The reason is obvious enough: the air in the tumbler having no vent remains in it, and prevents the water from occupying its place, so that the cork and candle, though apparently under water, are still floating, and surrounded by the air in the tumbler; the candle continues burning until the oxygen of the air is exhausted, and then it goes out, as would the life of a man under similar circumstances. If vessels full of air, like the barrels of Dr Halley, were submerged, and their contents poured into the tumbler, the light might be maintained; but this could be better done if a tube passed through the tumbler, and air were pumped from above through the tube into the tumbler. The modern diving-bell, which is made of casta iron like Smeaton's, is supplied with air in this manner. It must be remembered that air is compressible, and diminishes in bulk in proportion to the pressure, so that at a depth of about 33 feet in b water, it would occupy half the space it filled at the surface; if the inverted tumbler were carried to this depth, it would be halffilled with water. A considerable quantity of air has therefore to be pumped into the diving-bell, merely to keep it full as it descends; the air thus compressed exerts a corresponding pressure, and would rush up with great force if the tube were open and free. This is prevented by a valve opening downwards only. When the diving-bell has reached its full depth, the pumping is continued to supply air for respiration; and the redundant air overflows, or rather Diving-bell: a, section showing inside; b, top. underflows, by the open mouth, and ascends to the surface in great bubbles. The diving-bell is provided with a platform or seat for the workmen, and suspended from a suitable crane or beams projecting from a barge or pier; men above are stationed to work the pumps, and attend to the signals of the bellman. These signals can be made by striking the sides of the iron diving-bell with a hammer, and as sound is freely communicated through water, they are easily heard above. One blow signifies more air; two blows, 'stand fast;' three, heave up;' four, lower down;' five, 'to eastward;' six, 'to westward; &c. These, of course, may be modified as agreed upon. Messages may also be sent up written on a label attached to a cord. The telephone is now used. DIVING-DRESS.-In Schott's Technica Curiosa, published in 1664, is described a lorica aquatica, or aquatic armour, which consisted of a leathern dress and a helmet to protect the diver from the water. In 1721 Halley describes a contrivance of his own of nearly the same kind; its object was to enable the diver to go out from the bell and walk about. He was to be provided with a waterproof dress, and a small diving-bell, with glass front, as a helmet over his head, which was to be supplied with air by means of a tube from the diving-bell. Kleingert, of Breslau, in 1798 devised a diving-dress, consisting of strong tin-plate armour of cylindrical form encasing the diver's head and body; the lower portion of his person being clad in stout leathern costume. A pipe conveyed air to the diver, whilst a second pipe returned the air when vitiated to the surface. This apparatus was available only for depths up to 20 feet. The open helmet diving-dress was invented in 1829 by Augustus Siebe, and marked considerable advance on previous attempts. This dress consisted of a copper helmet with breastplate attached, a canvas jacket being fastened to the latter. The lower part of the jacket was left open (hence the name), and the air escaped by this outlet, hence the water was only a few inches below the diver's mouth, and he had to maintain a vertical position. Leather boots loaded with lead were also worn. In 1839 Siebe obviated the dangers attendant on the open dress by perfecting his close dress—a waterproof costume covering the whole body, save the head and hands, of strong tanned twill and rubber, with vulcanised rubber collars and cuffs. The helmet is made of tinned copper with three circular glasses in front; sometimes guards are added to protect them. The front eye-piece is made to unscrew and enable the diver to receive or give instructions without removing the helmet. One or more outlet valves are placed at the back or side of the helmet to allow the vitiated air to escape. These valves only open outwards by work ing against a spiral spring, so that no water can enter. The inlet valve is at the back of the helmet, and the air on entry is directed by three channels running along the top of the helmet to points above the eyepieces, enabling the diver always to inhale fresh air, whilst condensation on the glasses is avoided. The helmet is fixed to the breast plate below by a segmental screw-bayonet joint, securing attachment by one-eighth of a turn. In some dresses the escape valve is regulated at will by the diver, and enables him to vary the pressure, and even to float himself by closing the valve and inflating his dress, but except in the hands of a skilled man this may prove a source of danger. The junction between the waterproof dress and the breastplate is made watertight by means of studs, brass plates, and wing-nuts. The diver carries back and front weights, each about 40 lb. The boots, made of stout leather with leaden soles, weigh about 16 lb. each. The helmet weighs about 40 lb. A life or signal line enables the diver to communicate with those above; or the diver may speak to his attendant, or to other divers, by a telephone fitted to his helmet. The air-pipe is made of vulcanised india-rubber with galvanised iron wire imbedded. Diving-dress. the British Admiralty, two officers have done practical work in safety at 210 feet. Three United States divers have remained 5 to 27 minutes at the bottom at 275 feet. Slight men of muscular build, with good circulation, sound hearts, steady nerves, and temperate habits, make the best divers. The British Admiralty and Royal Engineers train a large staff of divers, as do other navies. Divining-rod, often called the Virgula Divina, the Baculus Divinatorius, the Caduceus or wand of Mercury, the Rod of Aaron, is a forked branch, usually of hazel, and sometimes of iron, or even of brass and copper, by means of which minerals and water are said to be discovered beneath the surface of the earth. The rod, when suspended by the two prongs, sometimes between the balls of the thumbs, indicates by a decided inclination the spot under which the concealed mine or spring is situated. It has often been used also to discover the authors of a crime, as by the famous Jacques Aymar in a case of murder and robbery at Lyons in 1692. Many men, even of scientific knowledge, have been believers in the occult power ascribed to this magic wand. Agricola, Sperlingius, and Kirchmayer all believed in its supernatural influence. Bayle, under the word Abaris, in his Dictionary, gives some ingenious arguments both for and against the divining rod. It seems to be still believed in, not only by Cornish miners, but by some English civic officials, men of science, and other responsible persons, even in the 20th century. Most scientific authorities regard this alleged power of the divining-rod as due to a more or less unconscious delusion, the phenomena merely being the effect of a strong impression on the mind acting through nerves and muscles. See Chevreul's De la Baguette divinatoire (1854), Lang's Custom and Myth (1884), and the testing experiments near Vincennes in March 1913, and at Guildford in April 1913. But see also Barrett in Proc. Soc. Psychical Research (1897, 1900). Divisibility is that property in virtue of which the whole may be broken up into parts. This process of division may be conceived to be carried on indefinitely so far as space is concerned. But the question of infinite divisibility as applied to matter at once raises the further question of the Atom (q.v.), and the Electron (q.v.). See also MATTER. A thickly gilt silver rod has been drawn out into a fine wire still covered with a continuous coating of gold the thickness of which must have been about gooth of an inch. A small particle of common salt placed in a flame will colour it for some hours; and one grain of musk can scent, by its slow evaporation, the air of a room for years. Divisibility, in the Theory of Numbers, is that property of any number whereby it may be divided by another without remainder. To find the condition of divisibility of one number, N, by another, D. Let N = b + b + b2 22 + ·· +bm-1 pm-1+bmm, where bo, by, &c. are coefficients, and r is the radix of the notational scale (see NOTATION). Introducing D and -D along with In the diving dress invented by Fleuss, and patented by him in 1880, the diver is independent of supplies of air from above. A strong copper cylinder fastened to the back of the diver carries a supply of compressed oxygen, regulated at will by a jamb screw-valve. The carbonic acid exhaled by the diver is absorbed by caustic soda in a receptacle fixed above the copper cylinder, whilst the nitrogen is breathed over and over again. In this dress, which weighs about 26 lb., and can be adjusted in a few seconds, a man may remain below the surface", this may be written: N = b. + b1 (D + r - D) for several hours without harm. In clear water and at moderate depths no light is required, but where illumination is necessary, an improved oil-lamp, invented by Siebe, supplied with air by a small force-pump, has been employed. Both arc and incandescent electric lights are now used for this purpose with most satisfactory results. Communication is made by means of the telephone, a slate, or ordinary signal line. Siebe states the greatest depth to which a man had ever descended to be 204 feet, equivalent to a pressure of 88 lb. per sq. inch; but by means of later methods used by + b (D+- D)2 + ... + bm (D + r – D)m. Expanding the terms on the right-hand side of this that will be an integer if D b. + b, (r-D+ ... + bm (r-D)m be divisible by D. For example, if r = 10 (i.e. if the number be given in the denary or ordinary scale), and D equation, it will appear N 9, and therefore r -D = 1, any number will be divisible by 9 if the sum of its coefficients be, by, &c. be so-i.e. if the sum of its digits be divisible by 9. Further rules found in this manner are fully given in Mackay's Arithmetical Exercises. * Exclusive of gun-carriages and bicycles. Of the latter there are 275, and 9 motor-cycles. The infantry 'guns' are machine-guns. Tent supply is not provided for in the normal establishment. Ammunition is provided by a series of reserves for infantry companies on pack-cobs, for batteries in 6-horse wagons, for battalions in 2-horse carts, for infantry and artillery brigades in 4-horse and 6-horse wagons, for the whole division in a horsed ammunition column, which is kept filled by an ammunition park of motor-lorries working from the advanced base. Three days' rations for men, and two days' forage for horses, are carried, chiefly by the supply train (horsed), which is kept filled by a motor supply column. In large foreign armies, Japan excepted, two divisions, similar to, but weaker than, the British, constitute an Army Corps (q.v.). A cavalry division is composed of a number of Brigades (q.v.), with horse-artillery batteries, squadron of engineers, ambulances, and a signal squadron. Naval Division.-For convenience of command and manoeuvring a fleet is divided into two, three, or more divisions, and each division into two subdivisions. Each division is commanded by a flag-officer. Division of Labour is based on the principle that industry can be best carried on when each man has a special work to do. Constant practice in doing the same thing leads to a perfection which could not otherwise be attained. The classical illustration of it in the history of political economy is that of pin-making as given by Adam Smith One man draws out the wire, another straights it, a third cuts it, a fourth points it, a fifth grinds it at the top for receiving the head; to make the head requires two or three distinct operations; to put it on is a peculiar business; to whiten the pin is another; it is even a trade by itself to put them into a paper; and the important business of making a pin is in this manner divided into above eighteen distinct operations, which in some manufactories are all performed by distinct hands.' In this way ten men could anake about 48,000 pins in a day, whereas, if they worked separately and independently, they certainly could not each of them have made twenty, perhaps not one pin in a day. Adam Smith offers the following reasons why the division of labour secures greater efficiency: First, the increase of dexterity in every particular workman; secondly, the saving of the time which is commonly lost in passing from one species of work to another; and lastly, the invention of a great number of machines which facilitate and abridge labour, and enable one man to do the work of many.' Economists believe, however, that Smith has laid too. great stress on both the second and third of the above reasons. Though the name of Adam Smith has been so closely associated with the principle of the division of labour, the importance of it had been recognised before, notably by Plato in his Republic, and by Adam Ferguson in his History of Civil Society. And it is hardly necessary to say that the inven tion of labour-saving machinery has rendered the example of the principle which he drew from pinmaking almost entirely obsolete as an illustration of the existing methods of industry. (A good example of division of labour is given under ČUT. LERY: an ordinary three-bladed pocket-knife goes through more than a hundred processes. See also NEEDLES.) Pins, which were made in thousands. through the co-operation of human hands, are now turned out in millions by the aid of machinery. In modern industry very little is due to the direct operation of the human hand; almost everything is done by a machine. The development of steam and electricity as the motive powers, both of production and exchange, has along with the parallel development of machinery completely revolutionised the conditions of industry, necessitating a division of labour on a far wider basis than that contemplated by Adam Smith. At the present day it is not a mere question of personal adaptation, but of local, national, and international fitness and specialisation for carrying on different forms of industry. Differences of climate and of other natural conditions, as well as differences of industrial development, impose upon nations a most comprehensive division of labour. This division of labour, it must be obvious, has as its necessary complement an elaborate combination or organisation of labour. In every large industrial undertaking, whether it be a factory, railway company, or any other, the highest efficiency can be attained only when, every man having his proper work to do, each man's work effectually contributes. towards the general result. It is only through the wise selection of the fittest persons for each class of work, and their special adaptation to it, that such an organisation can be maintained. Thus the division of labour is only a factor in the wider problem of the organisation of labour, necessary to the success of every great industrial undertaking. See LABOUR. But while the division of labour is necessary towards an efficient industry, economists recognise that it has many disadvantages. It is attended with a monotony of occupation, which is not favourable to the development of the general intelligence and capacity of the workmen. Each man can perform his own narrow function, and beyond that his skill does not go. The monotony itself is most painful, especially under the long hours of work which prevail in so many countries. But the worst feature of all is that through the changes which so frequently occur in the industrial world, owing to the introduction of new machinery and other causes, the class of work to which the men have been trained may be entirely superseded. The most striking instances of this in the history of English industry was hand-loom weaving, rendered obsolete by the introduction of the power-loom. Workmen thus trained and specialised have a great difficulty in finding, and in adapting themselves to, any other form of occupation. Division of Labour, a conception borrowed from Economics and introduced into Biology by Milne-Edwards, to describe the difference of function exhibited by the individual members of an |