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Article

glass  

Frederick Norman Pryce and Michael Vickers

Glass (ὕαλος (also 'rock crystal'), vitrum). The art of producing a vitreous surface on stone, powdered quartz (faience), or clay was known in pre-dynastic Egypt and passed to Crete during the second millennium bce. Glazed objects are common on Greek sites of the Archaic period, some of them Egyptian imports, others probably made locally. In Hellenistic and Roman times Egypt and Asia Minor were centres of fabrication of glazed wares, which often imitated bronze.Objects composed entirely of glass paste begin to appear in Egypt about 1500 bce, when two allied processes seem to have been in use: modelling molten glass about a core of sand, and pressing it into an open mould. The chief Mycenaean glass is dark blue imitating lapis lazuli, used for beads, inlays, and architectural ornaments. In the 6th cent. small vases made by the sand-core process became known in Greece; they have opaque blue, brown, or white bodies and a marbled effect was produced on their surface by means of a comb or spike. In the Hellenistic period mould-made bowls come into fashion; these were produced mainly in Egypt. Here the tradition of opaque polychrome glass was continued into Roman times with millefiori bowls, in which marbled and other polychrome patterns were formed by fusing glass canes of various colours and pressing them into moulds.

Article

H.E.M. Cool

Glass came of age during the Roman period. Within the ancient world it had been used from the mid-second millennium bce onwards, but only for jewellery and luxury items like small perfume bottles. This started to change in the late 2nd century bce, when the Hellenistic industries started to produce simple glass drinking vessels. In the early Imperial period there was an explosion in the vessel forms available, in part made possible by the discovery of how to blow glass. The new types included both the luxurious, such as exquisite cameo vessels, and the utilitarian, such as disposable packaging for cosmetics. A similar expansion was seen in its role in buildings, where glass went from luxurious interior decoration to structurally important window glass. References in literary works and depictions in wall paintings at the time attest to the considerable attention this new phenomenon attracted in the early to mid-1st century ce. Vessels, windows and other items spread widely throughout the empire and beyond, and to all levels of society. Over the next 400 years, how the material was used changed with time and place as the various regional industries responded to the needs and preferences of their communities. This was a major high-temperature industry which would have made considerable demands on resources such as fuel, but there are still many things that are unknown about it. Where, for example, was the glass itself made? Waste from secondary workshops producing vessels is regularly encountered, but evidence for the primary production is extremely rare. This has led to considerable debate, with competing models being proposed. Glass is not a material where scientific techniques such as those used to provenance pottery have proved very helpful. The composition of Roman glass is extremely uniform throughout the empire, and again there has been much debate about why this might be. Of late, some useful advances have started to be made in approaching these questions, and this may eventually disentangle what was going on. The study of Roman glass provides a unique window into the past. Through it the impact of new technologies and materials can be seen, as well as the choices people made about what was useful in their lives—all against the background of some of the most beautiful and skilful vessels ever made.

Article

Helen King

Gynaecology existed in the ancient world as a medical specialism, but its separate identity was not always permitted by wider medical theories. The significant question was this: do women have diseases peculiar to their sex, or are they subject to the same conditions as men, only requiring a separate branch of medicine to the extent that they have different organs to be affected? In other words, is gynaecology necessary?The majority of the surviving gynaecological treatises come from the Hippocratic corpus (see hippocrates (2)) and probably date to the late 5th and early 4th cents. bce. These treatises include three volumes of Gynaecia (Mul.), usually translated as ‘Diseases of Women’, but which can also mean women's sexual organs, *menstruation, or therapies for women's diseases. In contrast to the rest of the Hippocratic corpus, these texts include long lists of remedies using plant and animal ingredients. The third volume concerns the treatment of barren women. A separate short treatise discusses the medical problems of unmarried girls at puberty (Virg.

Article

heart  

Julius Rocca

The heart (καρδία, κῆρ) was one of the most discussed bodily parts in antiquity. This is due, not so much to any assertion that it was the centre of the vascular system, but that it was widely regarded it as the seat of cognition and governor of movement and sensation. From the Hellenistic era onwards, these supposed attributes were set against the counter claim that the brain mediated these functions. This debate remained unsettled, despite Galen’s efforts, and the heart’s association with emotional states persists to this day.Babylonian medicine possessed terms for the irregularity of the pulse, which served as labels for the heart. Egyptian medicine named the heart (ib, haty), and a vessel system (metu), which transported fluids of the body (including blood and air), as well as pathological and waste products. The connection between the heart beat and the peripheral pulse seems to have been recognised. The Iliad provides vivid examples of fatal wounds to the heart.

Article

Hegetor  

Heinrich von Staden

A physician of the ‘school’ of *Herophilus. The criticisms of Hegetor by *Ap.(8) of Citium (c.90–15 bce?) provide a terminus ante quem. Hegetor shared other Herophileans' keen interest in pulse theory, as Galen (8. 955 Kühn) and Marcellinus (On Pulses, ch. 3) confirm, but among later Herophileans he stands virtually alone in sharing Herophilus' emphasis on the importance of *anatomy. There is, however, no explicit evidence that Hegetor followed Herophilus' example of conducting systematic human dissection. In a fragment from his treatise On Causes (Περὶ αἰτιῶν), preserved by Ap. of Citium, Hegetor criticizes the Empiricists' use of analogy; he suggests that an exact knowledge of the anatomy of the thigh and of its attachment to the socket of the hip-joint, rather than analogies provided by the successful surgical treatment of other kinds of joints, would lead to a clear distinction between treatable and incurable cases of dislocated thigh bones.

Article

William David Ross and V. Nutton

Heliodorus (3), a popular surgeon of the time of *Juvenal (who lived c. 60–140 ce; cf. Juv. 6. 373), probably from Egypt. He belonged to the Pneumatic school (see pneumatists).

(1) Χειρουργούμενα (‘On Surgery’; principal work, chiefly known from Oribasius and in fragments preserved in late Latin translations);

(2) ? Περὶ ἀρθρων πραγματεία or Ἐπιμήχανος (‘Treatise on Joints’);

(3) Περὶ ὀλισθημάτων πραγματεία (‘On Dislocation’);

(4) Περὶ ἐπιδέσμων (‘On Bandages’);

(5) Περὶ μέτρων καὶ σταθμῶν (‘On Weights and Measures’);

(6) Epistula phlebotomiae (‘On Blood-letting’; Lat. trans.).

See surgery.

Article

Heraclides (4) of *Tarentum (fl. 85–65 BCE), a pupil of *Mantias and a renegade Herophilean (see herophilus), became one of the more influential, versatile, and theoretically nuanced physicians of the Empiricist school. He advocated experience as the foundation of medicine but freely accommodated causal explanation (e.g. correlating divergent causes of the same disorder with different treatments). His large treatise on external and internal therapy was used extensively by *Galen and Caelius Aurelianus, his dietetic Symposium by *Athenaeus(1) of Naucratis, his pharmacological works (including Theriaca) by Galen and Galen's sources (see pharmacology), and his extensive Hippocratic exegeses (including his influential polemics against Bacchius) by *Erotian and Galen; see hippocrates(2). Heraclides' pulse theory is known through Galen. About 90 fragments and testimonia survive.

Article

Herodotus (2), pupil of *Agathinus and adherent of the Pneumatic school of medicine (see pneumatists), wrote, in the Flavian period (70–96 ce), Physician and On remedies (lost); an extant Diagnosis of severe and chronic illnesses has been attributed to him on no secure grounds.

Article

Heron of *Alexandria (1), (fl. 62 ce) mathematician and inventor, was known as ὁ μηχανικός. The following works are associated with his name. (1) Metrica, three books, on the measurement of surfaces and bodies, and their division in a given ratio. (2) Definitions (Ὅροι), defining geometrical terms and concepts. (3) Geometrica, (4) Stereometrica, and (5) On Measures (Περὶ μέτρων), all works on mensuration. (6) Pneumatica, on the construction of devices worked by compressed air, steam, and water. (7) On Automata-making (Περὶ αὐτοματοποϊκῆς), mostly on the construction of θαύματα (‘wonder-working’ devices). (8) Mechanica, three books (extant only in Arabic, but excerpted by *Pappus book 8), on how to move weights with the least effort, containing (book 1) the foundations of *statics and dynamics, (book 2) the five simple machines, (book 3) the building of lifting-machines and presses. (9) Dioptra, on the construction and use of a sighting-instrument for measurement at a distance (with additions describing other instruments, e.g. a hodometer). (10) Catoptrica (extant only in Latin translation), on the theory and construction of plane and curved mirrors (see catoptrics).

Article

Herophilus of *Chalcedon (c. 330–260 bce), Alexandrian physician, pupil of *Praxagoras of Cos. He and *Erasistratus were the only ancient scientists to perform systematic scientific dissections of human cadavers. If the controversial but unequivocal evidence of several ancient authors is to be trusted, Herophilus also performed systematic vivisectory experiments on convicted criminals—experiments made possible, according to A. *Cornelius Celsus, only by royal intervention (see vivisection). Herophilus' numerous anatomical achievements included the discovery of the nerves. He distinguished between sensory and ‘voluntary’ (motor) nerves, described the paths of at least seven pairs of cranial nerves, and recognized the unique characteristics of the optic nerve. The first to observe and name the calamus scriptorius (a cavity in the floor of the fourth cerebral ventricle), he called it κάλαμος (‘reed pen’) because it resembles the carved out groove of a writing pen. His dissection of the eye yielded the distinction between cornea, retina, iris, and chorioid coat.

Article

Hicetas of *Syracuse (5th cent. bce), Pythagorean (see pythagoras(1)). Two inconsistent views are attributed to him: that the earth rotates on its axis while the rest of the heavenly bodies are motionless; and the theory associated with *Philolaus that the earth rotates about a central fire. See geocentricity.

Article

G. J. Toomer and Alexander Jones

Born at *Nicaea (1) in Bithynia, he spent much of his life in Rhodes; his recorded observations range from 147 to 127. His only extant work, the Commentary on theΦαινόμεναof Eudoxus and Aratus, in three books, contains criticisms of the descriptions and placings of the *constellations and stars by those two (see aratus(1); eudoxus(1)), and a list of simultaneous risings and settings. Valuable information on Hipparchus' own star coordinates has been extracted from it. Most of our knowledge of Hipparchus' other astronomical work comes from *Ptolemy(4)'s Almagest (see index under ‘Hipparchus’ in Toomer's trans.).Hipparchus transformed Greek astronomy from a theoretical to a practical science, by applying to the geometrical models (notably the eccentric/epicyclic hypothesis) that had been developed by his predecessors (see astronomy) numerical parameters derived from observations, thus making possible the prediction of celestial positions for any given time. In order to do this he also founded *trigonometry, by computing the first trigonometric function, a chord table.

Article

Geometer on curves called quadratrices (tetragōnizousai) for constructing the rectification of the circle and circular arcs (equivalent to the circle quadrature). The curve, earlier applied to this end by *Nicomedes(5) (late 3rd cent. bce), is also applicable for trisecting any angle, as may have been discovered by Dinostratus (mid-4th cent. bce).

Article

Hippocrates (2) of *Cos, probably a contemporary of Socrates (469–399 bce), was the most famous physician of antiquity and one of the least known. The important early corpus of medical writings bears his name (see medicine, § 4), but many scholars insist that he cannot be confidently connected with any individual treatise, let alone with any specific doctrines. He remains for many a ‘name without a work’, in the words of Wilamowitz; and even in antiquity the nature of his personal contributions to medicine were the subject of speculation.All kinds of anecdotes and medical doctrines have been connected at different times to the name of Hippocrates. One influential ancient biographical tradition, represented by a Life of Hippocrates (attributed to *Soranus of Ephesus and probably a source for several much later commentators including the Byzantine scholar Johannes *Tzetzes), maintains that he was taught medicine by his father and by the gymnastic trainer Herodicus of Selymbria (see dietetics), and that he sat at the feet of the sophist *Gorgias(1) of Leontini, the eponym of *Plato (1)'s dialogue.

Article

In geometry he was first to show that the cube duplication is equivalent to finding two mean proportionals between lines in the given ratio. He also constructed rectilinear figures equal to three forms of ‘lunules’ (mēniskoi), figures bounded by two circular arcs, alone or in combination with a circle (a problem related to the quadrature of the circle). A long fragment from *Eudemus on these quadratures is reported by Simplicius (in Phys. 1. 2, ed. Diels, 60–9). According to Proclus, Hippocrates was first to compile an ‘Elements’ of geometry, which would appear to have anticipated substantial parts of *Euclid's books 1, 3, and 6. In *astronomy, Hippocrates was known for a theory of comets, reported by Aristotle (Mete. 1. 6).

Article

honey  

Robert Sallares

Honey (μέλι; mel), the chief sweetener known to the ancients, who understood apiculture (Arist.Hist. an. 623b5–627b22; Verg. G. bk. 4) and appreciated the different honey-producing qualities of flowers and localities. Thyme honey from *Hymettus in Attica was very famous, both for its pale colour and sweet flavour; Corsican, harsh and bitter; Pontic, poisonous and inducing madness (Dioscorides, Materia medica 2. 101–3). Honey was used in cooking, confectionery, and as a preservative. It was used in medicines, e.g. for coughs, ulcers, and intestinal parasites (Theophr. Hist. pl. 9. 11. 3, 18. 8). It had a very important role in religion, cult, and mythology. Its religious associations derive from the idea that it was a ros caelestis (‘heavenly dew’), which fell on to flowers from the upper air for bees to gather (Arist.Hist. an. 553b29–30). According to poets it dripped from trees in the *golden age (Ov.

Article

humours  

J. T. Vallance

The words strictly suggest some kind of fluid substance and can be used of the sap in plants, but they are most commonly found in medical contexts. The explanation of disease—and even human behaviour—in terms of the interactions and relative proportions of fluids in the body is a very ancient one. In some Hippocratic treatises (see hippocrates(2)) the more general term ὑγρά (‘moistures’) is used as an alternative. At this level of generality there is little to distinguish many different pathological theories, but in practice there was little agreement as to which fluids counted as humours, and which were the most important. Many different kinds of humoral theory were in circulation. Most influential were those which related the qualities of the humours to qualities which had been associated with the Empedoclean *elements, where earth, water, *fire, and air were sometimes analysed in terms of hot, cold, wet, dry. This in turn enabled a correlation to be made with the four seasons. *Galen gives the four humours of the Hippocratic treatise On the Nature of Man—blood, phlegm, yellow bile, and black bile—a special status which they continued to enjoy.

Article

Wilbur R. Knorr

Hydrostatics, a special field of *statics, within the geometric theory of *mechanics, deals with the properties of weights in fluid media, and in particular with the conditions for stability of floating bodies. The basic principles and their application are from *Archimedes in the two books On Floating Bodies (Περὶ ὀχουμένων). Archimedes here demonstrates that a floating body displaces a volume of fluid equal to its own weight (book 1, prop. 5) and proves the stability of floating spherical segments (props. 8–9) and the conditions of density and shape entailing the stability of floating paraboloidal segments (book 2). The analogue for bodies denser than the medium, that is, that their weight when immersed in the fluid is reduced by an amount equal to the weight of the displaced fluid (book 1, prop. 7), can be extended into a procedure for determining specific weights, as in the hydrostatic balance attributed to Archimedes in the *Carmen de ponderibus.

Article

Hypatia  

G. J. Toomer

Woman learned in mathematics, astronomy, and philosophy (d. 415 ce). Daughter of the mathematician *Theon(4) of *Alexandria (1), she revised the third book of his Commentary on the Almagest. Commentaries by her on *Diophantus and *Apollonius(2) are lost. Influential in Alexandria as a teacher of Neoplatonist philosophy, she was torn to pieces by a mob of Christians at the instigation of their bishop (later Saint) Cyril (but see cyril of alexandria).

Article

J. T. Vallance

The English transliteration of the Greek word ὑπόθεσις can conceal something of the variety of senses this term has in ancient contexts. Etymologically it suggests ‘the basis upon which something else is grounded’. In Greek the term may be applied to the summary of the plot of a play (see hypothesis, literary), a political or legal proposal, a topic to be discussed, a proposition to be proved, an unprovable assumption which is the basis for deduction, an acceptable supposition which its author may or may not choose to prove, or a fully fledged model or system of explanation which permits further work. *Ptolemy(4) can describe his model of the wandering heavenly bodies, for example, as his ‘hypotheses’ of the planets. Strict logical senses of the term can be traced back at least to *Plato(1) and *Aristotle; Aristotle defines a hypothesis as a thesis which assumes either part of a contradiction as a basis for further deduction (An.