This page has been proofread, but needs to be validated.
  
OPTICS—ORACLE
141

For a discussion of the whole question, see M. Schanz, Geschichte der römischen Literatur, pt. i. p. 210 (2nd ed., 1898}; Teuffel-Schwabe, Hist. of Roman Literature (Eng. trans.), § 197; see also Cicero, Letters, ed. Tyrrell and Purser, iv. introd. p. 69.

OPTICS, the science of light, regarded as the medium of sight (Gr. ὄψις). Generally the noun is qualified by an adjective so as to delimit ate the principal groups of optical phenomena, e.g. geometrical optics, physical optics, meteorological optics, &c. Greek terminology included two adjectival forms—τὰ ὀπτικά, for all optical phenomena, including vision and the nature of light, and ἡ ὀπτική (sc. θεωρία), for the objective study of light, i.e. the nature of light itself and the theory of vision. See Light and Vision.

OPTION (Lat. optio, choice, choosing, optare, to choose), the action of choosing or thing chosen, choice or power or opportunity of making a choice. The word had a particular meaning in ecclesiastical law, where it was used of a right claimed by an archbishop to select one benefice from the diocese of a newly appointed bishop, the next presentation to which would fall to his, the archbishop’s, patronage. This right was abolished by various statutes in the early part of the 19th century. As a term in stock-exchange operations, “option” is used to express the privilege given to conclude a bargain at some future time at an agreed-upon price (see Call and Stock Exchange). The phrase “local option” has been specifically used in politics of the power given to the electorate of a particular district to choose whether licences for the sale of intoxicating liquor should be granted or not. This form of “local option” has been also and more rightly termed “local veto” (see Liquor Laws).

OPUS (Ὀποῦς), in ancient Greece, the chief city of the Opuntian Locrians; the walls of the town may still be seen on a hill about 6 m. S.E. of the modern Atalante, and about 1 m. from the channel which separates the mainland from Euboea. It is mentioned in the Homeric catalogue among the towns of the Locrians, who were led by Ajax Oileus; and there were games called Aiantea and an altar at Opus in honour of Ajax. Opus was also the birthplace of Patroclus. Pindar's Ninth Olympian Ode is mainly devoted to the glory and traditions of Opus. Its founder was Opus the son of Zeus and Protogeneia, the daughter of an Elian Opus, or, according to another version, of Deucalion and Pyrrha, and the wife of Locros. The Locrians deserted the Greek side in the Persian Wars; they were among the allies of Sparta in the Peloponnesian War. In the struggle between Philip V. of Macedon and the Romans the town went over to the latter in 197 B.C., but the Acropolis held out for Philip until his defeat at Cynoscephalae (Livy xxxii. 32). The town suffered from earthquakes, such as that which destroyed the neighbouring Atalante in 1894.

ORACH, or Mountain Spinach, known botanically as Atriplex hortensis, a tall-growing hardy annual, whose leaves, though coarsely flavoured, are used as a substitute for spinach, and to correct the acidity of sorrel. The white and the green are the most desirable varieties. The plant should be grown quickly in rich soil. It may be sown in rows 2 ft. apart, and about the same distance in the row, about March, and for succession again in June. If needful, water must be freely given, so as to maintain a rapid growth. A variety, A. hortensis var. rubra, commonly called red mountain spinach, is a hardy annual 3 to 4 ft. high with fine ornamental foliage.

ORACLE (Lat. oraculum, from orare, to pray; the corresponding Greek word is μαντεῖον or χρηστήριον), a special place where a deity is supposed to give a response, by the mouth of an inspired priest, to the inquiries of his votaries; or the actual response. The whole question of oracles—whether in the sense of the response or the sacred place—is bound up with that of magic, divination and omens, to the articles on which the reader is referred. They are commonly found in the earlier stages of religious culture among different nations. But it is as an ancient Greek institution that they are most interesting historically.

A characteristic feature of Greek religion which distinguishes it from many other systems of advanced cult was the wide prevalence of a ritual of divination and the prominence of certain oracular centres which were supposed to give voice to the will of Providence. An account of the oracles of Greece is concerned with the historical question about their growth, influence and career. But it is convenient to consider first the anthropologic question, as to the methods of divination practised in ancient Greece, their significance and the original ideas that inspired them. Only the slightest theoretical construction is possible here; and the true psychologic explanation of the mantic facts is of very recent discovery. In the Greek world these were of great variety, but nearly all the methods of divination found there can be traced among other communities, primitive and advanced, ancient and modern. The most obvious and useful classification of them is that of which Plato[1] was the author, who distinguishes between (a) the “sane” form of divination and (b) the ecstatic, enthusiastic or “insane” form. The first method appears to be cool and scientific, the diviner (μάντις) interpreting certain signs according to fixed principles of interpretation. The second is worked by the prophet, shaman or Pythoness, who is possessed and overpowered by the deity, and in temporary frenzy utters mystic speech under divine suggestion. To these we may add a third form (c), divination by communion with the spiritual world in dreams or through intercourse with the departed spirit: this resembles class (a) in that it does not necessarily involve ecstasy, and class (b) in that it assumes immediate rapport with some spiritual power.

It will be convenient first to give typical examples of these various processes of discovering the divine will, and then to sketch the history of Delphi, the leading centre of divination. We may subdivide the methods that fall under class (a), those that conform to the “omen”-system, according as they deal with the phenomena of the animate or the inanimate world; although this distinction would not be relevant in the period of primitive animistic thought. The Homeric poems attest that auguries from the flight and actions of birds were commonly observed in the earliest Hellenic period as they occasionally were in the later, but we have little evidence that this method was ever organized as it was at Rome into a regular system of state-divination, still less of state-craft. We can only quote the passage in the Antigone where Sophocles describes the method of Teiresias, who keeps an aviary where he studies and interprets the flight and the cries of the birds; it is probable that the poet was aware of some such practice actually in vogue. But the usual examples of Greek augury do not suggest deliberate and systematic observation; for instance, the phenomenon in the Iliad of the eagle seizing the snake and dropping it, or, in the Agamemnon of Aeschylus, of the eagles swooping on the pregnant hare. Other animals besides birds could furnish omens; we have an interesting story of the omen derived from the contest between a wolf and a bull which decided the question of the sovereignty of Argos when Danaus arrived and claimed the kingdom;[2] and the private superstitious man might be encouraged or depressed by any ominous sign derived from any part of the animal world. But it is very rare to find such omens habitually consulted in any public system of divination sanctioned by the state. We hear of a shrine of Apollo at Sura in Lycia,[3] where omens were taken from the movements of the sacred fish that were kept there in a tank; and again of a grove consecrated to this god in Epirus, where tame serpents were kept and fed by a priestess, who could predict a good or bad harvest according as they ate heartily or came willingly to her or not.[4]

But the method of animal divination that was most in vogue was the inspection of the inward parts of the victim offered upon the altar, and the interpretation of certain marks found there according to a conventional code. Sophocles in the passage referred to above gives us a glimpse of the prophet's procedure. A conspicuous example of an oracle organized on this principle was that of Zeus at Olympia, where soothsayers of the family of the Iamidai prophesied partly by the inspection of entrails,

  1. Phaedrus, p. 244.
  2. Serv. Verg. Aen. iv. 377; Paus. ii. 19. 3.
  3. Steph. Byz. s.v. Σοῦρα. Plut. De sollert. anim. p. 976 c. Ael. Nat. anim. xii. 1.
  4. Ael. Nat. anim. xi. 2.