Their enamel covering is confined to the apex, and soon wears away.
There is a splendid museum of medieval and Renaissance antiquities in the Bargello, the ancient palace of the Podesta, itself one of the finest buildings in the city; among its many treasures are works of Donatello, Ghiberti, Verrochio and other sculptors, and large collections of ivory, enamel and bronze ware.
Ao-Kutani, so called because of a green (ao) enamel of great brilliancy and beauty which was largely used in its decoration, and Kirtani with painted and enamelled pate varying from hard porcelain to pottery.
Enamel-ware is also manufactured.
Ear-rings (Evwrta, X¦o13ta, Exckt'7pES) of gold, silver, or bronze plated with gold, and frequently ornamented with pearls, precious stones, or enamel, were worn attached to the lobes of the ear.
Enamel and gilding were freely used, in imitation no doubt of the muchadmired vessels brought from Damascus.
It is Venetian in character, of a brownish tint, with two white enamel rings round the body.
In nearly all the other Pleistocene forms these teeth were subcylindrical in shape, with the summit of the crown (except sometimes in the first pair) forming a cup-like depression; enamel being in all cases absent.
There are three pairs of cheek-teeth which are rooted, and show folds of enamel on the crown.
It projects horizontally forwards from the head in the form of a cylindrical or slightly tapering, pointed tusk, composed of ivory, with a central cavity reaching almost to the apex, without enamel, and with the surface marked by spiral grooves and ridges, running in a sinistral direction.
The abbey church of St Pierre, dating chiefly from the 1 3 th century, contains, besides some fine stained glass, twelve representations of the apostles in enamel, executed about 1 547 by Leonard Limosin.
Sibircum of the Siberian Pleistocene, in which the premolars were reduced to while front-teeth were probably wanting, and the cheek teeth developed tall crowns, without roots, but with cement in the valleys, and the enamel of the central parts curiously crimped.
The white line of enamel, which is seen in some thermometers behind the bore, is introduced before the mass of glass is pulled out.
A flattened cake of viscous glass-enamel is welded on to one side of the mass of glass after it has been hollowed by blowing.
The mass, with the enamel attached, is dipped into the crucible and covered with a layer of transparent glass; the whole mass is then pulled out into tube.
In the later part of the 17th century some glass decorated with enamel was made at Delhi.
Cavies in general, the more typical representatives of the Caviidae, are rodents with hooflike nails, four front and three hind toes, imperfect collar-bones, and the cheek-teeth divided by folds of enamel into transverse plates.
In many cases we find large portions of the surface completely covered with green or yellow enamel overlying black diapers or scroll patterns.
Cloisonn Enamel.Cloisonn enamel is essentially of modern development in Japan.
Persistent roots and a partial enamel covering, those of the upper jaw not having the usual downward direction, but curving outwards, upwards and finally inwards, while those of the lower jaw are directed upwards and outwards with a gentle backward curve, their hinder edges working and wearing against the front edges of the upper pair.
In the wild boar (Sus scrofa) the upper or hinder surface of the lower tusk, which has no enamel, inclines obliquely outwards and is broader than the outer surface.
The lower canines are much more slender, but follow the same curve; except on the posterior surface, their crowns are covered with enamel; both pairs of canines are large in the two sexes.
The third or last molar tooth of both jaws is of great size, and presents a structure at first sight unlike that of any other mammal, being composed of numerous (22-25) parallel cylinders or columns, each with pulp-cavity, dentine and enamel-covering, and packed together with cement.
Upper incisors and the presence of distinct enamel-loops on the outer side of the lower molars.
Never more than one pair of premolars, and the original ridges of all the cheekteeth have become obscured and complicated by the development of secondary enamel-folds.
Mastodons have fewer ridges on their molar teeth than elephants; the ridges are also less elevated, wider apart, with a thicker enamel covering, and scarcely any cement filling the space between them.
When the summits of these are worn by mastication their surfaces present circles of dentine surrounded by a border of enamel, and as attrition proceeds different patterns are produced by the union of the bases of the cusps, a trefoil form being characteristic of some species.
Here was what seems to have been the basement of a very large hall or " Megaron," approached directly from the central court, and near this were found further reliefs, fresco representations of scenes of the bull-ring with female as well as male toreadors, and remains of a magnificent gaming-board of gold-plated ivory with intarsia work of crystal plaques set on silver plates and blue enamel (cyanus).
It is composed of figures of Christ, angels, prophets and saints, in Byzantine enamel run into gold plates.
To the north of Venice, was a great source of revenue to the republic. Glass drinking cups and ornamental vessels, some decorated with enamel painting, and "silvered" mirrors were produced in great quantities from the 14th century downwards, and exported.
When present in sufficient quantity the five last-named give enamel-white beads; lead oxide in excess gives a yellowish bead.
If the section of the finished tube is to be a triangle, with the enamel and bore at the base, the molten mass is pressed into a V-shaped mould before it is pulled out.
So few examples of glass vessels of this period which have been painted in enamel have come down to us that it has been questioned whether that art was then practised; but several specimens have been described which can leave no doubt on the point; decisive examples are afforded by two cups found at Vaspelev, in Denmark, engravings of which are published in the Annaler for Nordisk Oldkyndeghed for 1861, p. 305.
This is decorated with circles of rosettes of blue, green and red enamel, each surrounded by lines of gold; within the circles are little figures evidently suggested by antique originals, and precisely like similar figures found on carved ivory boxes of Byzantine origin dating from the II th or 12th century.
Cloisonn Enamel.Cloisonn enamel is essentially of modern development in Japan.
Many excellent examples of cloisonn enamel have been produced by each branch of this school.
It is apparent that a vitrified enamel may be made to perform, in part at any rate, the function of a porcelain glaze.
But to spread and fix the enamel so that neither at the rim nor in the interior shall there be any break of continuity, or any indication that the base is copper, not porcelain, demands quite exceptional skill.
Dentaries; some of the vertebrae in the lower region of the neck have strongly developed hypapophyses (not provided with a cap of enamel, as has often been asserted), which are directed forwards and pierce the oesophagus.
Besides these variations in the number of ridges or plates of which each tooth is composed, the thickness of the enamel varies so much as to have given rise to a distinction between a " thick-plated " and a " thin-plated " variety - the latter being most prevalent among specimens from the Arctic regions.
FLUORINE (symbol F, atomic weight iv), a chemical element of the halogen group. It is never found in the uncombined condition, but in combination with calcium as fluor-spar CaF2 it is widely distributed; it is also found in cryolite Na3A1F6, in fluor-apatite, CaF 2.3Ca 3 P 2 O 8, and in minute traces in seawater, in some mineral springs, and as a constituent of the enamel of the teeth.
In this group the enamel extends partially to the back of the incisors, but in all the rest it is restricted to the front surface, so that, by the more rapid wearing-away of the softer structures behind, a chisel-shaped edge is maintained.
In the latter there is only one pair of incisor teeth in the upper jaw, in which the enamel is confined to the front surface.
The second section, Castoroidea, of the present group includes only the family Castoridae, represented by the beavers, which are large aquatic rodents characterized by their massive skulls, devoid of post-orbital processes, with the angle of the lower jaw rounded, the molars rootless or semi-rooted, with re-entering enamel-folds, and one pair of premolars above and below.
Enamel-folds; the stomach has a large glandular mass situated to, the right of the oesophageal orifice; the anal and urino-genital.
The dentition includes one pair of premolars above and below, and rooted or rootless molars with but few enamel folds.
The Anomaluridae are characterized by having rooted cheek-teeth with shallow transverse enamel-folds, the two halves of the lower jaw movably articulated in front, very small post-orbital processes to the skull, and the presence of two rows of scales on the under surface of the base of the tail (figs.
In general habits and appearance these animals recall large jerboas, from which group they are, however, distinguished by the four pairs of rooted cheek-teeth, the premolars being as large as the molars, and the latter having one outer and one inner enamel-fold.
Glis) of Europe, with a doubly vaned, bushy tail, simple stomach, and large molars with well-marked enamel-folds; the second, Muscardinus, with M.
Avellanarius, the common dormouse, distinguished by the cylindrical bushy tail, and thickened glandular walls of the cardiac extremity of the oesophagus; thirdly, Eliomys, containing several species, with tufted and doubly vaned tails, simple stomachs and smaller molar teeth, having concave crowns and faintly marked enamel-folds; and lastly, the African Graphiurus, represented by several species, with short cylindrical tails ending in a pencil of hairs, and very small molars almost without trace of enamel-folds.
- The mole-rats (Spalacidae) bring us to the mouselike section, or Myoidea, in which there are no premolars and the molars may be occasionally reduced to z; these teeth being either rooted or rootless, with either cusps or enamel-folds, and the first generally larger than the second.
The Spalacidae are burrowing types, allied apparently to the ancestral Jaculidae, and characterized by the second and third molars being equal in size, the presence of enamel-folds in all these teeth, and the superiority in size of the claws of the second, third and fourth front toes over the other two.
In the typical Australian and Papuan Hydromys, locally known as water-rats, the molars originally have transverse ridges, the enamel folds between which form cutting edges whose sharpness depends upon the degree to which the teeth have been worn, while the large hind feet are webbed.
The upper lip is cleft, the jugal lacks an inferior angle, the fore part of the skull is short and broad; the cheek-teeth are partially rooted, with external and internal enamel-folds, the soles of the feet are smooth, there are six pairs of teats, the clavicles are imperfect and the tail is not prehensile.
Gilding and enamel decoration are applied to vessels when cold, and fixed by heat.
The last contains valuable specimens of the industrial art of the middle ages and of the Renaissance period in gold, silver, bronze, glass, enamel, ivory, iron and wood.
But the character of the old red differs essentially from that of the modern manufacture the former being a soft, subdued color, more like a bloom than an enamel; the latter a glossy and comparatively crude pigment.
2) differ from the corresponding organs of allied species in great breadth of the crown as compared with the length, the narrowness and crowding or close approximation of the ridges, the thinness of the enamel, and its straightness, parallelism and absence of " crimping," as seen on the worn surface or in a horizontal section of the tooth.
From the specimens with thick enamel plates the transition to the other species mentioned above, including E.