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قراءة كتاب Popular Technology; or, Professions and Trades. Vol. 2 (of 2)

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Popular Technology; or, Professions and Trades. Vol. 2 (of 2)

Popular Technology; or, Professions and Trades. Vol. 2 (of 2)

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دار النشر: Project Gutenberg
الصفحة رقم: 5

of Paris and bronze are taken from models, statues, busts, bas-reliefs, and living persons. To do this, it is necessary to form a mould from the subject to be copied. This is done by spreading over it some soft substance, which can be readily forced into all the cavities, and which will harden by drying or cooling. Plaster of Paris is the most usual material employed for this purpose.

9. When the subject is a bas-relief, or any other one-sided figure of a similar kind, the mould can be withdrawn without injury, in a single piece; but if it is a statue, or any other figure of like form, it is necessary to divide the mould into several pieces, in order to a safe removal. These pieces again united constitute a perfect mould. While the artist is forming the mould on the face of a living person, the latter breathes through tubes inserted into the nostrils.

10. In taking casts from such a mould, the internal surface is oiled to prevent adhesion, and then plaster mixed with water is poured into it through a small orifice. The mould is afterwards turned in every direction, that the plaster may cover every part of the surface; and when a sufficiency of it has been distributed to produce the requisite strength, and the plaster has acquired the proper solidity, the several pieces are removed from the cast, which, of course, is an exact resemblance of the subject on which the mould was formed.

11. Superfluous portions of the material, produced by the seams in the mould, are removed with suitable instruments, and applications of fresh plaster are made, where necessary to repair blemishes. The cast is finished by dipping it in a varnish made of soap, white wax, and water, and afterwards rubbing it with soft linen. The polish produced in this manner, approaches that of marble.

12. The durability of plaster casts, exposed to the weather, is greatly increased by saturating them with linseed oil combined with wax or rosin. They are made to resemble bronze by the application of a soap composed of linseed oil and soda, and colored with the sulphate of copper and iron.

13. Moulds are, also, formed of a warm solution of glue, which hardens upon cooling, and such are called elastic moulds. This material is sometimes preferred on account of its more easy separation from irregular surfaces. For small and delicate impressions in bas-relief, melted sulphur is sometimes employed; also a strong solution of isinglass in proof spirits. All three of the substances last mentioned yield sharper impressions than plaster of Paris.

14. Statues designed to occupy situations in which they may be exposed to the weather and mechanical violence, are often made of bronze cast in moulds. The external portions of the mould are made on the pattern, out of plaster, brick-dust, and water. The mould is then covered on the inside with a coating of clay as thick as the bronze is intended to be, and the several pieces are afterwards put together, or closed. The internal cavity is next filled with a composition like that on the other side of the clay.

15. When this has been done, the several pieces forming the outside of the mould are separated, and the clay carefully removed. These having been again united, and the core or internal portion of the mould secured in its true position, the whole is bound with iron hoops, and thoroughly dried. The melted bronze is poured into the cavity formed by the removal of the clay, through an aperture made for the purpose. The cast is afterwards rendered smooth by mechanical means.

16. It is conjectured with much reason, that sculpture was one of the arts practised before the deluge, and that it was transmitted to posterity by the survivors of that catastrophe. The first images were probably made for the purpose of perpetuating the memory of the dead; but, in process of time, they became objects of adoration. As the Chaldeans were unquestionably the first idolators after the flood, so are they supposed to have been the first who made progress in sculpture.

17. The first notice of this art in the Mosaic writings, is found in the passage relative to the teraphim, or idols, which Rachel, the wife of Jacob, carried clandestinely from her father's house; and the first persons mentioned in the Bible, as artists, are Aholiab and Bezaleel, who formed the cherubim which covered the mercy-seat, together with some other furniture of the tabernacle, and the sculptured ornaments of the garments of the high-priest.

18. From the same authority, we learn that the nations expelled from Canaan, by the Jewish people, were not ignorant of sculpture and painting; for Moses repeatedly commands the latter to destroy the pictures and molten images which might be discovered in their progress through the land. The Israelites crossed the river Jordan about 1500 years before the commencement of our era.

19. From this time to the end of the Jewish polity, we often meet in the Scriptures with indications of the fine arts; but the splendor of Solomon's temple, clearly points out the days of that prince as the period in which they had attained their greatest perfection in Judea.

20. The Babylonians, Assyrians, and Phœnicians, became considerably skilful in sculpture, at a very early period, as we learn from early history, and some existing remains. The same remark is also applicable to the inhabitants of Hindostan. But writers have been more particular in noticing the style of design among the Egyptians, because the progress of the arts among that people is more easily traced, and because it is supposed to elucidate that of most other ancient nations.

21. The chief objects of sculpture, among the Egyptians, were pillars, and other architectural ornaments, idols, the human figure, animals, and hieroglyphics, engraved in a kind of bas-relief on public edifices, and the forms of animals. Most of the great works of this nation are supposed to have been executed during and after the reign of Sesostris, who lived in the days of Rehoboam, king of Israel, or about 1000 years before the Christian era.

22. But of all the nations of antiquity, the Greeks were the most distinguished for sculpture. They derived the first rudiments of the art from the Phœnicians, or Egyptians, although they assert that they themselves were its inventors. Its existence, in a rude state, among that people, preceded that of letters or scientific architecture.

23. Dædalus, who lived about 100 years after Moses, was the first sculptor among the Greeks, of any notoriety. The statues made before his time, were stiff, formal figures, having the arms attached to the body, and the legs united, like the mummy-shaped productions of Egyptian art. He separated the legs of his statues, and placed them, and the upper extremities, in a natural position. He also was the first sculptor who made the eyes of his statues open. On account of these improvements, the Greeks said, that his divine genius made statues walk, and see, and speak.

24. The disciples and imitators of Dædalus were called his sons, and artists, generally, Dædalides. Soon after this period, schools of design were established in the island of Ægina, at Corinth, at Sicyon, and in Etruria, in Italy: but it seems that no good representations of the human form were effected until near the time of Phidias, who was born 444 years before Christ.

25. This most distinguished of all the votaries of sculpture, flourished at or near the same time with the dramatic poets, Æschylus, Euripides, and Sophocles; the philosophers, Socrates, Plato, and Anaxagoras; and the statesmen and commanders, Pericles, Miltiades, Themistocles, Cimon, and Xenophon. This was the most refined period of Grecian history, and of all others, the most favorable in its moral and political circumstances, for the development of

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