Page:The New International Encyclopædia 1st ed. v. 11.djvu/77

ieal power. His resolution of the attractions of ellipsoids, enunciated in 1809^ has been known ever since as 'Ivory's theorem.' In 1814 he re- euived the Copley jledal from the Royal Society for "a new method of determining a comet's orbit;" in 1820 the royal medal for a paper on refractions, which was eulogized by Laplace for its masterly analysis; and again in 18.39 the royal medal for his "Theoiy of Astronomical Re- fractions." He was elected to honorary member- ship in the most learned societies of Great Britain and other lands.

IVORYBILL. The great Southern woodpeck- er (CaiHiiephihis principalis), now confined to the cypress swamps of the Gulf States, and near- ly extinct. It is one of the largest of the tribe, and so impressed Linne by its size (length. 20 inches) and grandeur, that he called it 'prince.'

HEAD OF IVORYBILL. Its plumage is glossy black, with the secondary and shorter primaries pure white, and a white stripe down each side of the neck and along the scapulars, meeting in the middle of the back. The long crest of the male is scarlet, but that of the female is bluish-black; the bill is ivory-yel- low, straight, and chisel-like, capable of drilling lioh's in hard wood, and reaching the deeply buried grubs upon which it mainly feeds. This fine species was formerly a resident from the Po- tomac and Ohio rivers southward, and the early ornithologists have much to say of it. Audubon says its food included grapes, and that its nest was a hole, like that of other woodpeckers, dug by the' alternate labor of both mates, always in a living tree. He remarks its graceful flight — the bird seems merely to swing itself from the top of one tree to that of another in an elegantly curved line; and describes its notes as clear, h^ud, yet very plaintive. These birds were never very numerous, since they were constantly killed by the Indians, who valued highly their heads as ornaments and as symbols of dignity and courage. The frontiersmen, with barbaric love of color, copied the custom, and adorned their shot- pouches and caps with the gaudy crests, and ignorant Southern farmers killed them and all woodpeckers under the mistaken notion that they were destroying the forest trees.

IVORY-CARVING. I'nder this head must be included sculpture in bone, in vegetable, in wal- rus or narwhal ivory, and in fossil ivory, as well as that carved in the ivory of the elephant. It is. therefore, the whole subject of delicate and minute ornamental carving, except as done in wood and in fine hard stones. Pieces of reindeer- horn, as well as bone, are found with incised carvings on them under prehistoric remains: but horn is not often cut with the sharp tool for decorative purposes; it is usually softened and molded. In Egyptian tombs there have been found statuettes, handles of weapons, boxes, and the like, very delicately sculptured; and others have been found in Nineveh, especially tablets carved with significant figures in low relief. Some of the Egyptian pieces were of a time as early as 2000 B.C.; those of Nineveh, of the tenth century B.C. The most famous use of ivory in antiquity was in connection with the chrysele- phantine (q.v.) statues, of which, however, no remains are left.

There are many carved ivories of the later Roman Imperial time; consular diptychs and other tablets for writing, with bas-reliefs at the top and on the back. The history' of sculpture during the times of degeneration from the fourth to the eighth century can best be studied by means of these small but highly finished works. Under the Byzantine emperors the diptychs were still made, and there was much use of ivory in book-covers, as in the later Middle Ages.

The earlier Middle Ages used oblong caskets, made of solid blocks of ivory on the exterior, or of bone; or. in some cases, made of wood, which was concealed by the carved plates of ivory which cover the exterior. The backs of mirrors also and mirror-cases were made of this material, and elaborately carved throughout the Jliddle Ages. Purely devotional objects, too, were made, such as shrines, tabernacles, and the like; and dip- tychs mounted with silver or silver-gilt hinges and clasps were manufactured for travelers, in which the prefen-ed scenes and incidents were represented; thus, one might be devoted to the Passion of Christ, and another to the legend of some saint. The heads of pastoral staves and crosiers are sometimes of this material and elaborately carved. The finest pieces of niedia>val work in these materials are. however, the ad- mirable statuettes, such as those of the Madonna liolding the Child, one of which, small but of exquisite workmanship, is in the South Ken- sington JIuseum: while another, perhaps the fin- est ivory carving known, is in the sacristy of the little Church of Saint Pons, at Villeneuve-les- Avignon on the Rhone. This astonishing piece is admirably adorned with delicate painting and gilding; it is of unusually great size, and belongs to the finest sculpture of the fourteenth century.

A few pieces of carved ivory and bone of Sarii- cenic or Moorish work have reached Europe; but of Asiatic art, by far the best known and the most valuable is that of China and .Japan, Japanese art seems indeed to have followed its strong predilection for minuteness in undertak- ing the artistic treatment of very small masses of these hard materials. The little netsukes are more often of ivory than of any other substance, and their almost infinite variety and their sjiiritcd character are well known. Less known are the highly wrought boxes carved with reliefs, both higii and low, and adorned with little figures in the round which serve as knobs for the cov'er, or even for the feet of the piece.

In modern Europe, beginning with the sixteenth century, portraits in relief were common; these being carved in ivory with great fineness, and sometimes delicately colored in the costume, the eyes and hair, and the accessories. The whole school of ivon'-carving is known by the name of 'Dieppe ivories.' these being generally of the eighteenth century, and most commonly portrait