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After the tooth has becomo sacculated, and coincident with the transformation of the odontoblast cells of the dental papilla into dentine, calcification begins in the elongated prismatic cells of the internal or enamel epithelium; their protoplasm becomes calcified,

sixth year by the dropping out of the incisors. The last to be shed are the canines, which do not fall out till the tenth or eleventh year. The shedding of the milk teeth is preceded by the absorption of the fangs. This is effected as was satisfactorily shown by J.

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FIG. 21.-Vertical section through the gum in the region of the molar teeth. P, the papilla of a milk molar; 1, the inner, 2, the middle, and 3, the outer layers of the enamel organ; ", the neck of the enamel organ; e, the superficial epithelium; ct, ct, ct, the sub-epithelial connective tissue which subsequently forms the sac of the tooth; r, the cavity of reserve occupied by epithelium, in connection with which the permanent successional tooth is formed. X 300. and they become the rods or prisms of the enamel. As the bardening takes place from the periphery to the centre of each cell, the axial portion may, as Tomes pointed out, remain soft for some time in the axis of the enamel rod. With the increase in length, and with the calcification of the cells of the enamel epithelium, the stellate gelatinous cells disappear, and the outer ends of the enamel rods come in contact with the cells of the external enamei epithelium. By some observers the external epithelium is supposed to disappear without undergoing any special differentiation, but by others it is believed to undergo conversion into Nasmyth's

membrane.

In this manner the crown of a tooth is formed, and it is lodged in a membranous sac formed by the differentiation into a fibrovascular membrane of the surrounding connective tissue. Whilst within its sac, the crown of the tooth possesses the characteristic form of the group of teeth to which it belongs. After the calcification of the enamel rods is completed, it can undergo no further change either in shape or in increase of size.

Whilst the crown of the tooth is being formed, ossification of the jaws has been going on, and the tooth, with its membranous sac, has become lodged in an alveolus or socket in the jaw, which alveolus is closed in by the gum.

In order that the crown of the tooth may come into use as a masticatory organ, it has to be elevated to the level of the gum, which is absorbed by the pressure, and the crown then erupts into the cavity of the inouth. The process of eruption is due to the development of the fang, which, as it grows in length, elevates the crown of the tooth and forces it outward. The dentine of the fang is developed from the odontoblast cells of the pulp in a manner similar to that already described for the development of the dentine of the crown. The cement or crusta petrosa is developed from the connective tissue lining the alveolus, which forms the alveolo-dental periosteum. It is therefore an ossification in membrane.

As the temporary or milk teeth precede the permanent teeth, their papillæ are naturally the first to form. The series of milk papillae are not, however, simultaneously produced. From the observations of Goodsir, it has been shown that the milk-papilla of the anterior molar in the upper jaw appears about the seventh week; then the canine papilla, the two incisor papilla, and the posterior molar papilla are sucessively formed, the last making its appear. ance about the end of the tenth week. The dental papilla in the upper jaw immediately precede the papilla of the corresponding teeth in the lower jaw.

The eruption of the milk teeth into the mouth does not begin to take place until the latter half of the first year of extra-uterine life, and is not completed until betweeen the second and third year. Though variations occur in the date of eruption of each tooth in different children, it may be stated that the incisors usually appear from the seventh to the ninth month, the anterior molars from the twelth to the sixteenth month, the canines during the seventeenth or eighteenth month, the posterior milk molars from two to wo and a half years. The milk teeth begin to be shed about the

FIG. 22-One-half the lower jaw of a lotus about the 11th or 12th week, showing the dental papilla in the order of their appearance. 1, the first milk molar: 3 the canine; 3 and 4, the two incisors; 5, the second milk molar.-From Goodsir.

FIG. 23-Posterior part of the lower jaw of a child at birth. 5, the crown and sac of the posterior milk molar; 6, the crown and sac of the first permanent molar; b, the cavity in connection with which the papilla of the second permanent molar uitimately forms. y. shows a temporary and permanent incisor from the same foetus.-From Goodsir.

Tomes, by the agency of a group of cells situated at the bottom of the sockets. As these cells occasion absorption of the tooth tissue, similar to that occurring in the bone tissue from the action of the large multi-nucleated osteo-klast cells, they may appropriately be called odonto-klasts.

The development of the permanent teeth will now be considered. In the description of the arrangement of the teeth it has been pointed out that the number of teeth in the permanent set exceeds that of the temporary set. The permanent incisors and canines come into the place of the temporary incisors and canines, and the permanent bicuspids succeed the temporary molars, but the permanent molars have no milk predecessors, and are superadded at the back of the dental series.

The development of the successional permanent teeth, which are the ten anterior teeth in each jaw, will first be examined. Prior to the period when the lips of the primitive dental groove meet, to produce the saccular stage of dentition of the several temporary teeth, an indentation, or furrow, takes place in the connective tissue adjoining the string of epithelial cells which form the neck of the enamel organ. This furrow constitutes what Goodsir termed the cavity of reserve, and it is filled up by epithelial cells continuous with the epithelium of the neck of the enamel organ. As a cavity of reserve is formed immediately behind (i.e., on the lingual side of) each milk tooth, they are ten in number in each jaw, and, except that for the anterior molar, are formed successively from before backwards.

The cavities of reserve are concerned in the production of the permanent successional teeth, and each temporary tooth is replaced by the permanent tooth formed in connection with the cavity of reserve situated immediately behind it (fig 21). The cavities of reserve become elongated, and widened, and pass above the temporary teeth in the upper jaw, and below those in the lower jaw. At the bottom of each a dental papilla forms, the apex of which indentates and becomes covered by the epithelium contained in the cavity, which forms a cap for the papilla, and constitutes the enamel organ for the permanent tooth. The cavity becomes completely closed by the growth of the surrounding connective tissue, and the embryo permanent tooth becomes sacculated. The process of calcification then goes on, in both the enamel organ and dental papilla, in a manner similar to that already described in the temporary teeth. The permanent teeth then become lodged in sockets in the jaw distinct from those of the temporary teeth. The sac of each permanent tooth remains connected with the fibrous tissue of the gum by a slender fibrous band, or gubernaculum, which passes through a hole in the jaw immediately behind the corresponding milk tooth. Before the successional permanent tooth erupts, not only should the temporary tooth be shed, but the bony partition between their respective sockets must be absorbed.

The superadded permanent teeth, or permanent molars, three in number on each side, lie behind the successional teeth. Their mode of origin is similar to that of the temporary teeth. The primitive groove, occupied by an involution of the epithelial covering of the gum, is prolonged backwards. Three dental papillas successively appear at the bottom of this groove, and the epithelium covering each papilla forms its enamel organ. Legros and Magitot, however, state that the second permanent molar arises in connection with a diverticulum (cavity of reserve) proceeding from the epithelial string of the enamel organ of the first permanent molar, and that the wisdom tooth is formed in connection with a similar diverticulum from the second permanent molar. The embryo tooth becomes sacculated, and goes through the process of calcification similar to what has been described in the other teeth

The germ of the first permanent molar appears about the sixteenth week of embryo life; that of the second permanent molar not until about the seventh month after birth; whilst that of the wisdom tooth is not formed until about the sixth year The crown of the

B

FIG. 24.-A, the lower jaw of a child between four and five years old. 5, the last milk molar, with the successional bicuspid tooth in the cavity of reserve immediately below it; 6 and 7, the first and second permanent molars in their sacs; b, the cavity in connection with which the wisdom tooth is formed. B, the

lower jaw of a child about six years old; 6 and 7, the first and second permanent molars: 8, the papilla of the wisdom tooth developed in connection

with its cavity b.-From Goodsir

first molar is the first o. the permanent teeth to erupt into the mouth, which it usually does in the sixth year. The incisors appear when the child is seven or eight; the bicuspids when it is nine or ten; the canines about twelve; the second molars about thirteen; and the wisdom teeth from seventeen to twenty five.

In his dentition man is diphyodont as regards his incisor, canine, and premolar teeth, but monophyodont in the molar series. From the description of the development of the teeth, it will have been seen that a tooth is made up of three hard tissues-enamel, dentine, and cement-and of the soft vascular and nervous pulp. These tissues are not developed from one layer only of the blastoderm. The enamel is of epiblast origin, whilst the dentine, cement, and pulp are derived from the mesoblast. A tooth in its funda. mental develoj nent, as was long ago pointed out by Goodsir, must be referred to the same class of organs as the hairs and feathers. The enamel of the tooth, like the hair, is produced by a differentiation of the involuted epithelium of the epiblast, whilst the dentine and pulp resemble the papilla of the hair, in proceeding from the mesoblast. The tooth-sac, like the hair-follicle, is also of mesoblast origin. Whether the cement, as Robin and Magitot have described, be developed by means of a special cement organ, in the interior of the tooth-sac, or be formed, as has been stated in this description, by the alveolo-dental periosteum, it is on either view derived from the mesoblast. As to the origin of Nasmyth's membrane, there is a difference of opinion; some regard it as a special cornification of the external cells of the enamel organ, in which case it would be from the epiblast; whilst others consider it to be continuous with though structurally different from, the cement-homologous, therefore, with the layer of cement, which in the horse, ruminants, and some other mammals covers the surface of the crowns of the teeth. The tissues of a tooth have not all the same importance in the structure of a tooth. The dentine is apparently always present, but the enamel, or the enamel and cement, may be absent in the teeth of some animals. For example, the tusks of the elephant and narwhal, and the teeth of the Edentata, are without enamel, and in the Rodentia enamel is present on only the anterior surface of the incisors. But though the enamel is not developed, or forms only an imperfect covering for the crowns of these teeth, yet an enamel organ is formed in the embryo jaws. In 1872 W. Turner described a structure homologous with the enamel organ in relation with each of the dental papillae in the lower jaw of a foetal narwhal; but this organ did not exhibit a differentiation into the three epithelial layers, such as occurs in those teeth in which enamel is developed. Since then C. S. Tomes has seen an enamel organ in the embryo armadillo, and has also pointed out that, in teeth generally, enamel organs exist, quite irrespective of whether enamel subsequently does or does not form.

But further, the involution of the oral epithelium, and the coincident formation of a primitive groove, take place not only where the teeth subsequently arise, but along the whole curvature of the future jaws; whilst the production of dental papilla is restricted to the spots where the teeth are formed. Hence it would seem that the inflection of the oral epithelium is not so essential to the development of a tooth as the formation of a papilla. The inflected epithelium marks only a preliminary stage, and it may or may not be transformed into tooth structure. But that which is essential to the formation of a tooth is the production of the papilla which appears at the bottom of the primitive groove. (W. T.)

DIGITALIS, or FOXGLOVE, a genus of biennial and perennial plants of the natural order Scrophulariaceae. The common or purple foxglove, D. purpurea, is common in dry hilly pastures and rocky places and by road sides in various parts of Europe; it ranges in Great Britain from

Cornwall and Kent to Orkney, but it does not occur in Shetland or in some of the eastern counties of England. It flourishes best in siliceous soils, and is not found in the Jura and Swiss Aips. The characters of the plant are as follows:-stem erect, roundish, downy, leafy below, and from 18 inches to 6 feet or more in height; leaves alternate, crenate, rugose, ovate or elliptic-oblong, and of a dull green, with the under surface downy and paler than the upper; radical leaves together with their petioles often a foot in length; root of numerous, slender, whitish fibres; flowers 1-2 inches long, pendulous, on one side of the stem, purplish crimson, and hairy and marked with eye-like spots within; segments of calyx ovate, acute, cleft to the base; corolla obtuse, with the upper lobe entire or obscurely divided; stamens four and didynamous (see vol. iv. p. 138, fig. 226); anthers yellow and bilobed; capsule bivalved, ovate, and pointed; and seeds numerous, small, oblong, pitted, and of a pale brown. As Parkinson remarks of the plant, "It flowreth seldome before July, and the seed is ripe in August;" but it may occasionally be found in blossom as late as September. In one variety, common in gardens, the flowers are white; in another their purple is of a coppery or metallic hue; and not unfrequently in cultivated plants several of the uppermost blossoms may be united together so as to form a cup-shaped compound flower, through the centre of which the upper part of the stem passes. A figure of D. purpurea will be found in vol. iv. plate xi. Many species of foxglove with variouslycoloured flowers have been introduced into Britain from the Continent. The plants may be propagated by off-sets from the roots, but are best raised from seed.

The foxglove (Ang.-Sax., foxes-clife, foxes-glofa) is known by a great variety of popular names in Britain. In the south of Scotland it is called bloody fingers; further north, dead-men's-bells; and on the eastern borders, ladies' thimbles, wild mercury, and Scotch mercury. Among its Welsh synonyms are menyg-ellyllon (elves' gloves), menyg y llwynog (fox's gloves), bysedd cochion (red fingers), and bysedd y cwn (dog's fingers). In France its designations are gants de notre dame, and doigts de la Vierge. The German name fingerhut (thimble) suggested to Fuchs, in 1542, the employment of the Latin adjective digitalis as a designation for the plant.

The leaves, gathered from wild plants when about twothirds of their flowers are expanded, deprived usually of the petiole and the thicker part of the midrib, and dried, constitute the drug digitalis or digitalis folia of the pharmacopoeia. and bitter taste; to preserve their properties they must be The prepared leaves have a faint odour kept excluded from light in stoppered bottles. They are occasionally adulterated with the leaves of Inula Conyza, Ploughman's Spikenard, which may be distinguished by their greater roughness, their less divided margins, and their odour when rubbed; also with the leaves of Symphytum officinale, Comfrey, and of Verbascum Thapsus, Great Mullein, which unlike those of the foxglove have woolly upper and under surfaces. The powder, infusion, and tincture of digitalis are employed both externally and internally; and its active principle, digitalin, may further be used for subcutaneous injection. Digitalin, according to Nativelle, is a crystallizable, neutral, inodorous, bitter substance, of the formula CH40015, insoluble in water and ether, but soluble in alcohol and chloroform. The earliest known descriptions of the foxglove are those given by Fuchs and Tragus about the middle of the 16th century, but its virtues were doubtless known to herbalists at a much remoter period. Gerarde, in his Herbal (1597), advocates the use of foxglove for a variety of complaints; and John Parkinson, in the Theatrum Botanicum, or Theater of Plants (1540), tells us that

"The Italians have an usuall proverbe with them concerning this herb, called by them Aralda, which is Aralda tutte piaghe salda: Aralda salveth all sores..... It hath been found by late experience to be availeable for the King's Evill.... also to be effectuall against the Falling Sicknesse, that divers have been cured thereby." Later, Salmon, in The New London Dispensatory, praises the remedy foxglove in no measured terms.

Digitalis was first brought prominently under the notice of the medical profession by Dr W. Withering, who, in his Account of the Foxglove (1785), gave details of upwards of 200 cases, chiefly dropsical, in which it was used. Having become acquainted with the drug in 1775 as an ingredient in a Shropshire family receipt for the cure of dropsy, he began to administer it as a diuretic, but at first in doses too large; for, "misled by reasoning from the effect of the squills, which generally acts best upon the kidneys when it excites nausea," he sought to produce the same effect by foxglove. Further experience, however, convinced him "that its diuretic effects do not at all depend upon its exciting nausea or vomiting;" and that often the urinary discharge may be checked when the dose is imprudently urged so as to occasion sickness. He moreover observed that in cases where the drug produced purging it was inefficacious unless combined with small doses of opium, so as to restrain its action on the bowels. Withering seldom found it to succeed in men of great natural strength, tense fibre, warm skin, and florid complexion, or in those with a tight and cordy pulse. He recommended digitalis in every species of dropsy, except the encysted;" and he was of opinion that it might be made subservient to the cure of diseases unconnected with dropsy, and that its power over the motion of the heart, to a degree unobserved by him in any other medicine, might be turned to good account by the physician.

The experiments of Marcet and Brunton show that the infusion of digitalis has a poisonous effect on various plants, and, even in very small quantity, kills fishes,-their auricles after death being found distended, their ventricles strongly contracted. On birds the effect of the infusion is to cause firm contraction of the left ventricle, and consequent excessive congestion of the lungs. A large turkey, according to M. Salerne (Hist. de l'Académie. 1748, p. 120, 12mo, and p. 84, 4to ed.), walked as if intoxicated, in consequence of partaking once of foxglove leaves. Another turkey, weighing 7 lb, ate during 4 days about half a handful of the leaves, after which it refused nourishment, and in a couple of weeks died, its weight being reduced to 3 lb. Handfield Jones and Fuller have proved that the infusion produces upon the hearts of frogs and mammals effects similar to those observed in birds. The usual results of small and repeated doses of digitalis are contraction of the capillaries, and augmented arterial blood-pressure, with slower and more powerful cardiac systole, and an increase in the urinary secretions; large or long-continued doses, besides causing nausea or vomiting, often accompanied by purging, occasion a slow or irregular pulse, dilatation of the capillaries, decrease in the rate of respiration, cold sweats, disordered vision, chilliness of the extremities, giddi ness, and great weakness, followed by convulsions and insensibility. Syncope is apt to occur on sudden changes of posture by patients fully under the influence of the drug. Its cumulative action, or unexpected production of alarmingly acute symptoms, may arise either from an increase in the dose, the elimination of the drug being constant, or from a check in the elimination, the dose remaining unaltered, hence the caution with which digitalis should be administered in cases where the renal functions are disturbed. The experiments of various physiologists have shown that digitalis, by stimulating the sympathetic ganglia of the heart, causes the contraction of its musculo-motor fibres, this effect being at first masked by a similar action on the pneumogastric nerves. By effecting more complete emptying of the ventricles in cases of cardiac disturbance, digitalis improves the circulation, bringing about in the lungs a more thorough oxidation of the blood. The consequent increased nutrition of the heart is promotive of hypertrophy in that organ; small doses of digitalis are therefore an assistance in hypertrophy following upon cardiac injury. In cases of dilatation of the heart, on the other hand, large doses are required. The continued use of the drug when the heart has become sufficiently hypertrophied may render ventricular action excessive. Digitalis calms excitement of the heart not by acting as a narcotic or sedative but by stimulating its nerves, and enabling it to contract without laboured effort. In feeble con.

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ditions of the circulation it acts diuretically by increasing arterial tension, but its influence as a diuretic is not constant. Its efficacy in epilepsy appears to be limited by its action on the circula tion. In enteric fever, erysipelas, and acute rheumatism, it has been employed to reduce temperature. Its use as a sedative in objected to on the ground that it cuts off the irritating blood pneumonia, delirium tremens, and some other discases has been supply only by an extreme degree of ventricular contraction. Ia arachnitis in children, in inflammation tending towards serous effusion, in dropsy, hæmorrhage, cerebral anaemia, and occasionally in angina pectoris and nervous palpitation, it is a valuable remedy. Upon the uterus digitalis acts by stimulating the ganglia in which its motor power resides (W. Howship Dickenson, in Med. Chir. Trans. vol. xxxix. Lond. 1856). In poisoning by digitalis, aconite and probably also Calabar bean may be resorted to.

A. L. J. Bayle, Bibliotheque de Therapeutique, tom. fil. pp. 1-372; Christison, A Treatise on Poisons, p. 886, 4th ed. 1855; Sir H. Holland, Medicas Notes and Reflections, chap. xxix. 3d ed., 1855; Trousseau et Pidoux. Traité de Therapeutique, vol. ii. p. 754, 1862; T. L. Brunton, On Digitalis, 1868; J. Milner Fothergill, Digitalis, its Mode of Action, and its Use, 1871; Pereira, Materia Medica, 1874; Garrod, Materia Medica, 1814; G. W. Balfour, Clinical Lectures in the Diseases of the Heart and Aorta, pp. 97 and 304, 1876. (F. II. B.)

Alpes, in France, about 70 miles north-east of Marseilles, DIGNE, the chief town of the department of Bassesin 44° 5' 32" N. lat. and 6° 14′ 6′′ E. long. It is built on a spur of the mountains jutting out into a gorge traversed by the Bléonne, which in winter is a formidable torrent, rich in orchards, which have long made the town famous in but in summer is almost dry; and the neighbourhood is France for its preserved fruits and confections. The streets Boulevard Gassendi, at the upper end of which is a public are narrow and tortuous, with the exception of the garden, with a statue of the philosopher, who was born in The cathedral the neighbouring village of Chantercier. within the town is a building of very hybrid architecture, and is of less importance than the cathedral of Notre Dame, in numbered among the historic monuments of France. The the vicinity, which dates from the 12th century, and is thermal springs are not in much repute, and the bathing establishment is in a state of decay. Digne is identified with Dinia, the capital of the Avantici and Bodiontici. It carly became an ecclesiastical see, and its bishops acquired the secular rank of barons of Lauzières. In the 16th century it suffered on four separate occasions from the Huguenot soldiery; and in modern history it is known as the place from which Napoleon issued his proclamation of March 1815. Population in 1872, 5300 in the town and 6877 in the commune.

DIJON (Divio, Dibio, or Divionense Castrum), the chief town of the department of Côte-d'Or in France, and formerly capital of the province of Burgundy, is situated at the foot of Mount Affrique, in a fertile plain, on the Burgundy canal, and at the confluence of the Ouche and Suzon, in 47° 19′ 19′′ N. lat., and 5° 2′ 5′′ E. long. The streets are broad and well built of freestone, and there are fifteen squares; an abundant supply of water is obtained from the vale of Suzon by means of a subterranean aqueduct nearly eight miles in length. Among the more noteworthy of the public edifices are the cathedral of St Bénigne, in the Gothie style of the 13th century, with a spire erected in 1742; the church of Notre Dame built in 1331-1445, containing a group in stone, the Assumption of the Virgin, by Dubois, and a statue of the Black Virgin, celebrated in the Middle Ages; the church of St Michel, of the 16th century; the general hospital, founded by Otho III. in 1206; the castle. commenced in 1478 by Louis XI., and finished in 1512 by Louis XII., once a state prison, in which the duchess of Maine, Mirabeau, the Chevalier d'Eon, and Toussaint Louverture were confined, and since then a barrack for gendarmes; and the old palace of the dukes of Burgundy, or hotel de ville, rebuilt between the end of the 17th and the end of the 18th century, in which are an art collection, the archives, a museum of natural history, a school of arts, and the salle des gardes, containing the

tombs of Philippe le Hardi and Jean sans Peur. Important | power to cut down timber, destroy buildings, &c. (voluntary structures also are the lunatic asylum, the ancient court- waste), or to let buildings fall into disrepair (permissive house, the theatre, and the hospice Saint-Anne, and numer- waste). In the eye of the law an incumbent is a tenant for ous other educational establishments. Dijon possesses a life of his benefice, and any waste, voluntary or permissive, library of 70,000 volumes and 900 manuscripts, a picture on his part must be made good by his administrators to his gallery, a collection of coins and of, 40,000 engrav- successor in office. The principles on which such dilapidaings, a jardin des plantes and herbarium, and a fine tions are to be ascertained, and the application of the money park, commenced in 1670, after the designs of Le Nôtre, payable in respect thereof, depend partly on old ecclesiastiby the Great Condé, and finished by his son. It is the cal law and partly on recent Acts of Parliament. Questions seat of a bishop, and of tribunals of primary instance and as to dilapidations usually arise in respect of the residence house and other buildings belonging to the living. Inclosures, hedges, ditches, and the like are included in things" of which the beneficed person hath the burden and charge of reparation." In a leading case (Ross v. Adcock, 37 Law Journal, C.P. 290) it was said that the court was acquainted with no precedent or decision extending the liability of the executors of a deceased incumbent to any species of waste beyond dilapidation of the houso, chancel, or other buildings or fences of the benefice. And it has been held that the mere mismanagement or miscultivation of the ecclesiastical lands will not give rise to an action for dilapidations. To place the law relating to dilapidations on a more satisfactory footing, the Act 34 and 35 Vict. c. 43 was passed. The buildings to which the Act applies are defined to be such houses of residence, chancels, walls, fences, and other buildings and things as the incumbent of the benefice is by law and custom bound to maintain in repair. In each diocese a surveyor is to be appointed by the archdeacons and rural deans subject to the approval of the bishop; and such surveyor shall by the direction of the bishop examine the buildings on the following occasions--viz, 1, when the benefice is sequestrated; 2, when it is vacant; 3, at the request of the incumbent or on complaint by the archdeacon, rural dean, or patron. The surveyor is to specify the works required, and to give an estimate of their probable cost. In the case of a vacant benefice, the new incumbent and the old incumbent or his representatives may lodge objections to the surveyor's report on any grounds of fact or law, and the bishop, after consideration, may make an order for the repairs and their cost, for which the late incumbent or his representatives are liable. The sum so stated shall be a debt due from the late incumbent or his representatives to the new incumbent, who shall pay over the money when recovered to the governors of Queen Anne's Bounty. The governors pay for the works on execution on receipt of a certificate from the surveyor; and the surveyor, when the works have been completed to his satisfaction, shall give a certificate to that effect, the effect of which, so far as regards the incumbent, will be to protect him from liability for dilapidations for the next five years. Unnecessary buildings belonging to a residence house may, by the authority of the bishop and with the consent of the patron, be removed. An amending statute (35 and 36 Vict. c. 96) relates chiefly to advances by the governors of Queen Anne's Bounty for the purposes of the Act.

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commerce, and has faculties of law, science, and literature. The ramparts that formerly surrounded the town have been replaced by broad avenues. The principal industries are the manufacture of hosiery, woollen and cotton cloth, Paris lace, leather, candles, earthenware, mustard, confections, vinegar, and chemicals; iron and type-founding, printing and binding, brewing, saltpetre-refining, and nursery-gardening. Dijon does an important trade in cereals, and is the chief emporium for Burgundy wines. The population of the commune in 1872 was 42,573; that of the town, 40,116.

Dijon was a fortified camp of the Romans, and about 274 was enlarged by Aurelian. In 731 it was taken and burnt by the Saracens. Councils were held there in 1077, 1116, and 1199 or 1200. Early in the 12th century the town was almost entirely destroyed by fire, but it was soon rebuilt. Till 1107 it was held by the counts of Dijon, and from 1179 to the death of Charles the Bold in 1477 it was the residence of the dukes of Burgundy; it then came into the possession of Louis XI., who established there the Burgundian "Parlement." In 1513 Dijon was besieged by 20,000 Swiss, with whom a humiliating treaty was concluded. On October 31, 1870, the town capitulated to General Werder; it was evacuated by the Germans on the 27th of December, and early in January 1871 became the head-quarters of the French eastern army under Bourbaki. On the 1st of the following February it was reoccupied by the Germans. Dijon is the birthplace of Bossuet, Jacques Cazotte, the elder Crébillon, Danbenton, Jouffroy, Long pierre, Bernard de la Monnoie, Guyton de Morvcan, Piron, Rameau, and Saumaise.

DILAPIDATIONS, in English law, is the name given to the waste committed by the incumbent of an ecclesiastical living. By the general law a tenant for life has no

Thus a mere

DILIGENCE, in law, is the care which a person is bound to exercise in his relations with others. The possible degrees of diligence are of course numerous, and the same degree is not required in all cases. depositary would not be held bound to the same degree of diligence as a person borrowing an article for his own use and benefit. Jurists, following the divisions of the civil law, have concurred in fixing three approximate standards of diligence-viz.,, ordinary, less than ordinary, and more than ordinary. Ordinary or common diligence is defined by Story (On Bailments) as "that degree of diligence which men in general exert in respect of their own concerns." Sir William Jones:-" This care, which every person of commou prudence and capable of governing a family takes of

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his own concerns, is a proper measure of that which would uniformly be required in performing every contract, if there were not strong reasons for exacting in some of them a greater and permitting in others a less degree of attention" (Essay on Bailments). The highest degree of diligence would be that which only very prudent persons bestow on their own concerns; the lowest, that which even careless persons bestow on their own concerns. The want of these various degrees of diligence is negligence in corresponding degrees. These approximations indicate roughly the greater or less severity with which the law will judge the performance of different classes of contracts; but English judges have been inclined to repudiate the distinction as a useless refinement of the jurists. Thus Baron Rolfe could see no difference between negligence and gross negligence; it was the same thing with the addition of a vituperative epithet. See NEGLIGENCE.

Diligence, in Scots law, is a general term for the process by which persons, lands, or effects are attached on execu tion, or in security for debt.

DILKE, SIR CHARLES WENTWORTH (1810-1869), Baronet, born in London, February 18, 1810, was the only son of Charles Wentworth Dilke, proprietor and editor of the Athenæum, and was educated at Westminster school and Trinity Hall, Cambridge. He studied law, and in 1834 took his degree of LL.B.; but he did not enter upon the practice of his profession. He assisted his father in his literary work, and afterwards gave up much of his time to several of the learned societies. He was for some years chairman of the council of the Society of Arts, and took a prominent part in the affairs of the Royal Horticultural Society. He was one of the inost zealous promoters of the Great Exhibition (1851), and a member of the executive committee. At the close of the exhibition he was honoured by foreign sovereigns, and the Queen offered him knighthood, which, however, he did not accept; he also declined a large remuneration offered by the royal commission. In 1853 Dilke was one of the English commissioners at the New York Industrial Exhibition, and prepared a report on it. He again declined to receive any money reward for his services. He was appointed one of the five royal commissioners for the Great Exhibition of 1862; and soon after the death of the Prince Consort he was created baronet by the Queen. In 1865 he entered parliament as member for Wallingford. In 1869 he was sent to Russia as representative of England at the Horticultural Exhibition held at St Petersburg. His health, however, had been for some time failing, and he died suddenly in that city, May 10, 1869. He was a fellow of the Society of Antiquaries, and a member of other learned bodies.

DILL (dnethum), a genus of umbelliferous plants having decompound leaves; umbels without involucre; yellow flowers, with calices incomplete above; and lenticular fruit, compressed from back to front, flattened at the margin, and presenting on each side three ridges. The common species, A. graveolens, is indigenous to the south of Europe, Egypt, and the Cape of Good Hope. It resembles fennel in appearance. Its root is long and fusiform; the stem is round, jointed, and about. a yard high; the leaves have fragrant folioles; and the fruits are brown, oval, and concavo-convex. The plant flowers from June till August in England. The seeds are sown, preferably as soon as ripe, either broadcast or in drills between 6 and 12 inches asunder. The young plants should be thinned when three or four weeks old, so as to be at distances of about 10 inches. A sheltered spot and dry soil are needed for the production of the seed in the climate of England. The leaves of the dill are used in soups and sauces, and, as well as the umbels. for flavouring pickles.

The seeds are employed for the preparation of dill-water and oil of dill (valued for their carminative properties), are largely consumed in the manufacture of gin, and, when ground, are eaten as a condiment in the East. See BOTANY, vol. iv. p. 123.

DILLEN (DILLENTUS], JOHANN JAKOB (1687-1747), & distinguished botanist, was born at Darmstadt. He was educated at the university of Giessen, where he received his doctor's diploma, but he early turned his attention from medicine to the study of plants. Whilst at Giessen he wrote several botanical papers for the Ephemerides Naturæ Curiosorum, and in 1719 he printed there his Catalogus Plantarum sponte circa Gissam nascentium, a little octavo volume illustrated with figures drawn and engraved by his own hand, and containing descriptions of many new genera. In the preface he discusses the classifications of Rivinus, Tournefort, Knaut, and Ray, the last of which was that adopted by him. In 1718 Dillen became acquainted in Germany with the botanist William Sherard, who invited him to come to England. Soon after his arrival there, in 1721, he took up his abode at Oxford, where Sherard resided. In 1724 he published an enlarged edition of Ray's Synopsis Stirpium Britannicarum. In accordance with the will of Sherard, who died in 1728, Dillen was appointed professor of botany at Oxford. He published in 1732, in two volumes folio, with 324 plates executed by himself, the Hortus Elthamensis, of which Linnæus wrote "Est opus botanicum quo absolutius mundus non vidit.". That naturalist spent a month with Dillen at Oxford in 1736, and afterwards dedicated to him his Critice Botanica. In 1741 appeared the Historia Muscorum of Dillen, to whom and his contemporary Micheli (1679-1731) cryptogamic botany owes its origin. He died April 2, 1747, in his sixtieth year. A print from his picture at Oxford is to be seen in Sim and König's Annals of Botany, vol. ii. His books and collection of mosses, with many drawings, were bought by his successor at Oxford, Dr Humphrey Sibthorp, and added to the Sherardian Museum.

DILLINGEN, a town of Bavaria, in the circle of Schwaben-Neuburg, on the left bank of the Danube, 24 miles north-west of Augsburg. Its principal structures are the royal palace, formerly the residence of the bishops of Augsburg, the royal gymnasium and Latin school, with a library of 75,000 volumes, five churches, two episcopal seminaries, a Capuchin monastery, a Franciscan nunnery, and a deaf and dumb asylum. The university, founded in 1549, was abolished in 1804, being converted into a lyceum. The inhabitants, who in 1875 numbered 5029, are engaged in cattle-rearing, the cultivation of corn, hops, and fruit, ship-building and the shipping trade, and the manufac ture of cloth, paper, and cutlery. Dillingen was taken by the Swedes in 1632 and 1648, by the Austrians in 1702, and on the 18th July 1800 by the French.

DIMENSIONS. In geometry a line is said to be of one dimension, a surface of two, and a solid of three dimensions. The use of the word is extended to algebraical terms, which are said to be of n dimensions with respect to any quantity when that quantity enters to the nth power.

If the term contains several variables, x, y, z, &c., and if the sum of the indices of these variables is n, the term is said to be of n dimensions with respect to the system of variables x, y, z.

If all the terms of an equation are of n dimensions with respect to the system of variables 2, 1, 2, the equation is said to be homogeneous of n dimensions with respect to that system of variables.

The equation may or may not be homogeneous with respect to another system of variables which occur in it, as p, q, r.

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