Concepts of the Origin and Physiology of Tears: From Prehistoric Times Through the XVIII Century

Sources In Time Juan Murube, MD, PhD, editor

Concepts of the Origin and Physiology of Tears: From Prehistoric Times Through the XVIII Century Juan Murube, MD, PhD

he overflow of tears from the lacrimal basin was recognized millennia ago. It was usually due to reflex and psycho-emotional tearing, but, sometimes, to normal basal tear secretion in cases of lacrimal pathway occlusion. The first questions about the origin of tears were related to conspicuous tearing. Where are tears produced? How do they enter the eye? How do they reach the ocular surface?

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EARLY HISTORY Our prehistoric ancestors related life to the heart, which was the most clearly perceived constantly active organ of the inner body (Figure 1).1 The traditional association of the heart with life, passion, and love still persists symbolically today as the source of emotion, sentiment, and religious expression. Ancient Egypt With the evolution of intellect and culture, the origin of tears began to be elucidated in Pharaonic Egypt. The first manuscript discovered about the source of tears is the Ebers papyrus of the Pharaonic Egyptian culture, which dates to about 1550 BC.2,3 At that time, it was believed that the origin of tear was the heart. The body had a Juan Murube, MD, is Professor of Ophthalmology, University of Alcalá (Madrid, Spain).

©2011 Ethis Communications, Inc. The Ocular Surface ISSN: 1542-0124. Murube J. Concepts of the origin and physiology of tears: from prehistoric times through the XVIII century. 2011;9(4):191-196.

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Figure 1. The original drawing (A) and the Abbé Breuil reproduction (B) of a mammoth (Elephas primigenius) or elephant (Elephas antiquus) of the Paleolithic cave of Pindal in Asturian Spain, about 30,000 years ago. A heart-shaped image is in the place where the heart is situated, probably to indicate the center of its life or to show the hunter where to aim to kill. (Size = 42.5 cm x 44.5 cm.1)

system of channels or ducts, known as metu, including veins, arteries, nerves, tendons, and ducts, through which flowed water, mucus, blood, or other fluids. Via these channels, fluids were carried to their corresponding metu in their specific part of the body. Tear and any secretion from the eyes arose from the heart. Four vessels [inner and outer carotids?]* which ran inside the temples [intracranial?] transferred to the eyes all the humors they needed, including tears. Tears moved outside the eye through the pupils. Tears and cataracts represented an excess of water in the eye. The orbital cavity also was connected to the holes of the nose by two vessels (perhaps referring to the lacrimonasal duct). The Chimu culture existed be-

tween the X and XV century AD in what is now Peru. Because it had no communication with the Mesopotamian-Mediterranean-Western European cultures, its knowledge and beliefs were comparable to those of Pharaonic Egypt. The belief that tears come from inside the eye and through the pupil and cornea is illustrated in the mask shown in Figure 2.

Ancient Greece Homer (ca VIII century BC) believed, in general, that emotions and thoughts originated in the chest or in the diaphragm.4 Millennia later, the physician and poet Empedocles of Agrigentum (ca 490-430 BC) still believed that the heart was the organ of thought, ideas, and feelings.5

*Throughout, italicized terms in brackets are the author’s interpretation.

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types were air-filled.11 Greek medicine began to flourish when it began Aristotle (384-322 BC) to be based more on emretained some previous erpiric and technical experoneous concepts, still conrience than on religious sidering the heart to be the and popular superstitious primary organ of soul, where ideas. However, human sensations, intelligence, and body dissection was not common sense dwelt. He acyet practiced, and rudimencepted some new concepts, tary anatomical concepts eg, during respiration, the were maintained. The nerair entered through the vous system was unknown. mouth and nose, going What is known today as the directly to the cerebrum, vascular system was poorly then to the veins, which Figure 2. Golden mask found in Chimu tomb (X-XV century, currently interpreted, with the veins distributed the pneuma to Peru). A string of pearls representing tears comes out of each pupil. being the best known bethe eyes, nose, ear, bowels, cause of their easy perception under the heart.7 lungs, and the rest of the body. He also the skin. Physics was based on the accepted that the surfocular tears were When the cerebrum was overfour elements (water, earth, air, and heated, the mucus it contained became an efflux of the aqueous humor, which fire). Physiology was related to the four fluid and flowed downward into the worked like a purgative, draining and body humors (blood, phlegma, yellow eyes, the nose, the mouth, and the purifying the entire organism.12 Aris8 bilis, and black bilis), and circulation urinary tract. A vessel (referring totle wrote that there were two kinds of the vital air (pneuma), water, and of tears: hot and cold. Hot tears were to the optic nerve or maybe to the other fluids varied with temperature the normal tears produced when crychiasma) reached from the covering and humidity. The mixture of humors ing; cold tears were those produced in of the cerebrum into both eyes; the produced different temperaments and association with disease.13 cerebrum passed the thinnest of its diseases. Ancient Greeks did not asviscous products through these two Cassius Iatrosophista (II century sociate the function of the heart with vessels. AD), a medical writer during the clasthe blood, nor the air with the lungs. Tears were a secretion of the brain sical Greco-Roman period, wrote that The veins distributed the air, phlegm, similar to nasal phlegm—“…the fluxes the aqueous humor is the origin of the and other humors to the cavities of the coming from the cerebrum formed tears on the ocular surface. He also body and the cerebrum. secretions through the ears, eyes, and believed that tears were a purgative of Maybe it was because the eyes (orinose”—and several other phlegms the entire body, purifying and draingin of vision, tears, and expression), passed to the pharynx, to the stomach, ing off noxious substances.14 nose (inhaling and exhaling of vital to the back and the hips. Galen (ca 129-199 AD) lived about pneuma), ears (sounds ) and mouth Vision was a light that came out half a millennium after Hippocrates, in (receiver of food) were anatomically from the brain to the eyes through the II century AD. He was active and close to the brain that, little by little, hollow optic nerves, and it was proimpetuous, and considered himself vision, tears, bilis, saliva, and other jected by the eyes to the objects of the the scientific successor of Hippocrates, humors, as well as intelligence and visual field as a flash. Most translators modifying some of his concepts. Galen feelings, came to be attributed to the interpret these early writings to mean was the first to write that arteries did cerebrum. Alcmaeon of Croton (V that these hollow nerves transmit the not carry air, but blood. Nevertheless, century BC) dissected living animals vision and humors, including tears.9 he did not recognize that veins and arand deduced that mental activity teries were two different subsystems of Plato (427-347 BC) had different comes from the cerebrum, that cutting the same bloody circulation. His belief ideas, and he connected the origin of the nerve behind the eye causes the that venous and arterial systems were tears with vision.10 Tears were formed animal to lose vision, and that the eye separate persisted until Servetus and inside the eyeball. Fire inside the eye contains both fire and water.6 Harvey’s work in the XVI and XVII comprised the principle of vision. centuries. When this fire came in contact and Hippocrates of Kos (ca 460-370 Galen believed that the cerebrum mixed with the moisture inside the BC), who is considered the seed of produced fluids, some of which were eye, tears were formed. modern medicine, ushered in a new evacuated through the arteries and Praxagoras of Kos (ca 340 BC) medical epoch. He wrote that the reached their final target in the form differentiated eleven different humors cerebrum was a gland controlling the of tears and sweat.15 He accepted the in the body. He was one of the first most important human functions, physicians to differentiate between the and that pleasure, laughter, pain, grief, cerebral origin of tears, and made function of the veins and arteries, alvision, hearing, and weeping (tears) three interesting observations in his though he believed that both vascular came from the cerebrum and not from books about tear flow: the existence 192

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of lacrimal glands, the ca[ca 865-925]) considered runcula, and the palpebral much of the information lipid glands. from Greco-Roman, MidGalen noted for the first dle Eastern, and Indian time the existence of lacrimedicine, and maintained mal glands in the eye as the the previous idea that the immediate source of tears cerebrum was the origin of that poured onto the ocular copious tear flow. Rhazes surface. “In order to fadiffered from Galen, decilitate the movements, also scribing a total decussation there are two glands in each of the optic nerves at the eye, one in the lower part chiasma.20 and the other one in the The Al-andalusi Abulupper part, which outflow casis of Cordoba (Abul their humidity through visKasim [ca 936-1013]) wrote Figure 3. Modern diagram of Hunain’s sketch of the eye from 860 ible ducts, just as the glands that the tears came from the AD. (Modified from Meyerhof M: The book of the ten treatises on the of the root of the tongue cerebrum and went to the eye ascribed to Hunain. Cairo, 1928.) externalize saliva into the inner angle of the eye. They mouth.”16 came to the eye through the arteries lid margin and back again by way (he used the term sarayanat, specific Galen used the Greek term of the lower [posterior] parts of the for arteries) or veins (uruq, used for “aden-,” which is still maintained in lids [the conjunctiva]. At the point veins and arteries). When the tears the neologisms denoting “gland.” It is where the periostium began to run came from the intracranial vessels, unknown whether or not he recogback [the lid rims], there was a harder they were persistent and incurable nized the main lacrimal glands or only membrane called the tarsus. This tardespite treatment. But when tears the puncta of the lacrimal canaliculi, sus was pierced with fine holes from came through extracranial dilated which he erroneously interpreted as which the hairs of the eyelids emerged. uruq of the forehead and temple, as the source of tears. He did not speViscous fatty substances occupied in some diseases (pterygium, inner cifically reject the idea that some tears the space between the two parts of angle wounds, or caustications), they could also come from the brain, so we the periosteum, and this was where could be cured by eating purified do not know his thoughts about this. the so-called hydatids [styes?] were foods for the brain, washing the head Hyrtl maintained that, for the formed when the fatty bodies made by with aloes, cauterizing the temple and ancient Greeks, the lacrimal gland was Nature converted to oil and softened retroauricular region, performing an an enigmatic organ which Galen did the eyelid, which became abnormally arteriotomy, and/or by making three not dare to name.17 Many centuries large.16 Galen´s work survived for parallel incisions in the forehead.21 later, the British anatomist Thomas centuries and was the main source of Wharton (1656) called the dubious The Persian Avicenna (Ibn Sina medical information in the Christian gland described by Galen the “glan[980-1037]), one of the three most and Mohammedan cultures until the dula innominata of Galen.”18 important physicians of Antiquity XVIII century. (with Aristotle and Galen) wrote that About the caruncle, Galen wrote, tears originated in the cerebrum, and “at the canthus major [medial angle] MEDIEVAL ARABIC CULTURE accepted that they arrived to the eyes is a flesh-like body [soma sarkodes, The medieval Arabic culture did through one of two channels (intracracaruncula]. It is there to protect the not substantially change the ideas nial veins and extracranial veins). He two orifices from which secretion runs presented by Galen. wrote about the chiasma, but did not from the eyes into the nose [lacrimal The Syrian Hunain Ibn Ishak mention how the tears passed from the pathways]. It prevents overflowing of (809-877) was a Nestorian Christian brain to the eyes.22 the tears at the canthus and directs who translated most of Galen’s manuthe tears into the appropriate openscripts. He wrote that the lacrimal flow ings. If the flesh-like body is destroyed MEDIEVAL CHRISTIAN CULTURE came from the cerebrum, either from epiphora will result”... “these openings During the Middle Ages, no imthe interior part of the cranium when lead into the nose and either produce portant new ideas emerged about the the external veins were undilated but or drain fluid, as the necessity arises.”16 sources of tears. the person sneezed frequently, or from Bartholomaeus Anglicus.(ca Galen also observed the tarsal the exterior part of the cranium when 1203–1272) wrote that “the flow of lipid glands, which he said fused with the veins of the forehead and temples tears came involuntarily because of the eyelash pilosebaceous glands. He were dilated. Tears reached the eye external causes such as a knock, cold described the eyelids as an expanthrough the [optic] hollow nerve or hot air, smoke, dust, smell of garlic sion of the upper and lower orbital (Figure 3).19 or onion. 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passed through veins that internal causes such as cold cross the lamina cribosa or hot humors, or because between the cranium and of the great abundance of the eye. He also cited sebahumors, which could not ceous tarsal glands of the be retained by the brain.”23 lids, which, consistent with Guglielmus de Saliceto belief until recently, he did (ca 1210-1277), on denot relate with the surfocuscribing the technique of lar tear film.31,32 reclination of cataract, instructed the surgeon: “Be The French Cartesius at the side of the patient, (René Descartes, 1596this one lying in supine 1650) believed that the Figure 4. A. Portrait of Andreas Vesalius from his De humani corporis position. Have his head vapors of the brain travfabrica (1543).27 B. Drawing of the base of the cerebrum showing the between your legs, and you, eled to the eye through pairs of cranial nerves, by Andrea Vesalius (1543). surgeon, open the eye of the the optic nerves and went patient, and blow strongly to the pores of the ocular on it in order for the tears to come out.” surface, where they converted into amplified this conception, describing Then he described the puncturing of liquid. He wrote that, just as the vapor the continuous cardiovascular blood the eyeball and the reclination of the of the clouds converted into water, flow.29 cataract. The author did not explain tears came out of the eyes as vapor The Spaniard Juan Fragoso (1530whether the objective of the provoked and converted into water on the eye 1597), naturalist and surgeon, maintearing was to clean the inner eye or surface. When the shape of the pores tained most of the Galenic ideas, and for some other purpose.24 changed for any reason, such as a straw wrote that when there were abundant falling in the eyes, the pain produced Petrus Hispanus (ca 1205-1277) exhalations in the concavities of the a narrowing of the pores, and the wrote that overabundance of phlegm cerebrum because of sadness, they vapor went out more slowly and its was manifested as tears or running discharged the heaviness of this husmall elements converted into tears. eyes. Further, he noted that humors mor through the flesh and by way of With respect to tears of sadness, Desdescending into the eyes must be treatthe eyes. In the same way “as fog was cartes wrote that sadness cooled the ed with cauterization at the temples.25 transformed into drops of water, the blood and narrowed the pores of the Benvenutus Grassus (also known hard vapors converted into tears, and eye, and, at the same time, the heart as Benvenutus of Jerusalem [XIII so the people are able to relieve their pushed blood to the eyes. The reason century]) maintained the Galenic sadness when weeping.”30 why children and elderly people wept concept that tears sprouted from the The Italian anatomist Julius Casmore than younger adults was that two lacrimal puncta. He added that serius (ca 1556-1616) wrote that tears when the elderly felt love or joy, the those from the lower punctum came heart sent out large amounts of blood, from the heart when one suffered great but as the aged were cold, it was conpain, and that those from the upper verted into tears; and as children had punctum came from the cerebrum a large amount of blood, when its flow and were due to corruption or excess was slowed because of sadness, it was of humors.26 converted into tear.33 RENAISSANCE AND MODERN ERA The Danish Nicolaus Steno (Niels Steensen [1638-1686]) was a physiThe Belgian Andreas Vesalius cian, anatomist, geologist, researcher, (Andries van Wesel [1514-1564]), and member of a religious order professor of surgery at the University (Figure 5). He was the first to show of Padua, dissected human cadavers that the heart was simply a complex and tried to correlate some of Galen’s muscle, the main motor that sent the descriptions and concepts with his blood through arteries and veins. He anatomical observations (Figure 4).27 had learned that tears came from the Michael Servetus (1511-1553) in cerebrum, and they flowed through 1553 described the cardiopulmonary the vessels to the eyes. He looked for blood circulation, noting that blood the innominate lacrimal glands of flowed from the heart to the lungs, Figure 5. Portrait of Nicolaus Steno conserved in the Uffizi Gallery of Florence, Italy. Galen, and, dissecting the head of a where it mixed with air to form the arIn 1675, he emigrated to Florence, where he sheep, he discovered and described terial blood, which flowed back to the entered the priesthood and remained until in 1662 for the first time the excretory heart and was distributed to the entire he died. He is buried there. ducts that connected an orbital gland body.28 William Harvey (1578-1657) 194

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to the lacrimal basin. He related this gland with the glands cited by Galen, despite its very different location and the lack of connection with the lacrimal puncta, and wrote that this gland was the origin of tears. Steno also described the excretory duct of the salivary parotid gland, currently known with his eponym.34 He also described the excretory duct of the salivary submandibular gland, almost simultaneously with Wharton.18 The existence of a main lacrimal gland was soon accepted, and about a century later, additional glands were identified, currently known as “secondary or accessory” lacrimal glands. Wharton (1614-1673) maintained the idea that the brain was the origin of tears, but rejected the old concept that it was the fountain of mucus. He believed that the brain, when very affected by sorrow and grief, produced tears, which were expressed in the paroxisms of grief, reaching the eyes by travelling through the nerves. He rejected the Casserius concept that the lamina cribosa connected the tear veins with the eye, because the lamina cribosa connects the cerebrum with the nose, but not with the orbit. In 1662, 6 years after Wharton named the “glandula innominata of Galen,” Steno identified the true lacrimosecretory nature of the real main lacrimal gland.18,34 In 1666, the German Heinrich Meibomius (16381700) described the sebaceous tarsal glands, which had already been very superficially cited by Galen and Casserius. His accurate description led to the eponymous naming of these glands.35 That tears transpirated from inside the eye to the ocular surface was the most commonly accepted idea before lacrimal glands were confirmed to exist by Steno. The two theories about the origin of tears—from the cerebrum (Hippocrates) and/or the lacrimal glands (Galen, Steno)—were, in fact, complementary, but, little by little, the more “modern” idea of the exocrine lacrimal gland enhanced the importance of lacrimal gland secretion. However, in the last third of the XVIII century, the French Jean Janin

Figure 6. Position and blood vascular supply of the main lacrimal gland depicted in Zinn’s 1780 book.38 Upper aspect of the content of the right orbit. The lacrimal gland is between the eyeball and the lateral bone of the orbit. The lacrimal gland is covering the lateral rectus muscle, and is covered by the orbicularis muscle of the upper lid. The vascular supply is shown).

(1732-1799) wrote that the lacrimal glands produced only one third of the total lacrimal secretion, and the rest was produced through the cornea, conjunctiva, tarsus, and caruncula.36 According to Janin (1772), each eye produced about 20-25 grains (1.25 g) of tears, ie, about 2 ounces (60 g) a day. The cornea was transversed by many canals, which carried the aqueous fluid coming from the vitreous and aqueous humor; and the conjunctiva, caruncula and meibomian glands received a similar fluid from their arterioles and lymphatics. If the eye of a living animal was kept open with a speculum oculi (blepharostat) and its cornea and conjunctiva were dried, small drops would gradually appear over the corneal, conjunctival, and tarsal surfaces coming from these canals and pores. The conjunctiva also had many of its own conjunctival glands. The caruncula had excretory unctuous sebaceous secretion, and the tarsus had many glands the size of a grain of opium poppy. The meibomian glands served as dikes to contain the tears, and diminished the “acrimony” of the tear and the ocular surface.36 Janin is considered by most research-

ers to have suggested for the first time that in addition to reflex and psychoemotional tear secretion, there existed a continuous basal lacrimal secretion. Jean-François Lavoisien, a French military surgeon, maintained the idea of his time that tears were produced to maintain the homeostasis of the body. He wrote in 1793 that “the needless excremental corporal humors were those which were expelled out of the body because they were useless for its nutrition and might be dangerous if they were retained. There were twelve: urine, sweat, substances of the perspiration, sebaceous humors of the skin, trachea-artery, tears, sleep of the eye, mucus of the nose, cerumen of the ear, menstrual blood, hemorrhoidal blood, and puerperial lochia.”37 In the XVII and XVIII centuries, the macroscopic position and irrigation of the lacrimal glands were being defined (Figure 6).38 The German Johann Christian Rosenmüller (1771-1820), anatomist and surgeon, described in 1797 the anatomy of the palpebral portion of the main lacrimal gland, as anatomically independent of the orbital part. This palpebral portion is frequently termed the Rosenmüller lacrimal gland.39 The innervation of the lacrimal gland and the neural system were imprecisely understood at the end of the XVIII century. The trigeminus and the facial nerves, although described by Avicenna in the XI century22 and Fallopius in the XVI century,40 were better specified by Wrisberg,41 but their motor and sensorial functions were not elucidated until the XIX century. In the next two issues of this journal, new discoveries about the aquoserous, mucinic and lipid dacryogland in the XIX and XX centuries will be discussed.

REFERENCES 1. Breuil H. Quatre cent siècles d’art parétal [Four hundred centuries of cave art]. Montignac: Centr Étud Doc Préhist, 1952 2. Ebers papyrus. ca. 1550 BC (Quoted by Ebers,3 Hirschberg,42 Dollfus,43 and Murube44) 3. Ebers G. Papyros Ebers: Das hermetische Buch über die Arzeneimittel der alten Ägypter [Ebers papyrus: The hermetic book on medica-

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ORIGIN AND PHYSIOLOGY OF TEARS / Murube tions of the ancient Egyptian], with a glossary from the hieroglyphics to Latin by L. Stern. Leipzig, 1875. Edited by G. Ebers 4. Homer.Odysseia[Odyssey]. ca.VIII century BC 5. Empedocles of Agrigentum. Perí Physeos [On nature]. V century BC 6. Alcmaeon of Croton. Perí physikon [On Nature]. V Century BC 7. Hippocrates. Perì adénon [About the glands]. (V-IV century BC). 11, 565. 8. Hippocrates. Perì hierês nósou [On the sacred disease]. V-IV century BC, chapt 10, 17, 19, 20 9. Hippocrates. Peri sarkón [On fleshes]. V-IV century BC (Quoted by Hirschberg 42) 10. Plato. Timaeus, 68. IV century BC (Quoted by Magnus45) 11. Praxagoras of Kos (Quoted by Lyons & Petrucelli46) 12. Aristotle. Perì neotetos kai géros, kai zoes kai thanáton, kai ánapnoes [On youth and old age, life & death, and respiration]. IVth century BC Spanish translation. Madrid: Edit Gredos, 1987, pp 317-63 13. Aristotle. Problemata [Problems] Book XXXI, 22, 959b, 16), IV century BC 14. Cassius Iatrosophista. Iatrikai aporíai kai problémata physicá [Medical questions and phisical promblems]. II Century AD, Edit. in Paris 1541. (Quoted by Magnus,45, Ideler,47 and Pensier48) 15. Galen. Perí philosóphou historías [History of phylosophy]. II century AD, Vol XIX, page 338 16. Galen. Perí xreias moríon [On the usefulness of the parts of the body]. II century AD. English translation. Ithaca, New York. Cornell University Press. 1968, Vol. II, pp 78, 79, 90, 91, 463-503 17. Hyrtl J. Handbuch der topographischen Anatomie [Handbook of topigraphical anatomy]. 1847,Vol II, ed 2 18. Wharton T. Adenographia, sive glandularum totius corporis descriptio [Adenografia, or description of the glands of the entire body]. London, 1656 and Amsterdam 1659. Translated by Andrew Cunningham. Oxford. Clarendon Press, 1996 19. Hunain Ibn Ishak. Ashr maqalat fil-ain [Treatises on the structure of the eye]. Manuscript ca. 860. Translated by Meyerhof C. The book of the ten treatises on the eye ascribed to Hunain. Cairo: Government Press, 1928 20. Razhes (Al-Rhazi). Al-Hawi [The content of Medicine]. X century AD. Arabic 21. Abulcasis of Cordoba (Abul Kasim). Kitab al Tasrif [Book of Medical Practice] Manuscript nº 5007 of the Biblioteca Nacional de Madrid. Treatise II, fol. 67 and 69. Arabic 22. Avicenna (Ibn Sina). Kitab Alqanun Fi Altibb [The Canon of Medicine]. XI century. Edition in Cairo: Ed. Bulaq. 1877. Book 3. Arab ic

196

23. Bartholomaeus Anglicus. De proprietatibus rerum [On the properties of things]. Manuscript from 1240. John Trevisa’s Translation of Bartholomaeus Anglicus. De proprietatibus rerum: A Critical Text. Gen ed MC Seymour. Oxford, Clarendon Press, 1975-1988 24. Guilielmus de Saliceto. Chirurgia, 1275 [Italian] [Surgery]. (French translation  by N Prévot. Paris, Jean Petit, 1507, and by P Pifteau. Toulouse, Saint-Cyprien, 1898) 25. Petrus Hispanus. Liber de oculo [Book on the eye] Manuscript ca. 1255, in Berger AM. Die Ophthalmologie (Liber de Oculo) des Petrus Hispanus (Petrus von Lissabon). Munich, Lehmann, 1899 26. Benvenutus Crassus (alias of Jerusalem or Salerno). “De oculis,” ”Practica oculorum,” or “De probatissima arte oculorum” [The wonderful art of the eyes]. (Manuscript. XIII century. Cited by Pansier MP, Histoire de l’Óphtalmologie. In Lagrange F, et al. Encyclopédie Française d’Ophtalmologie. Vol I, pp 30-31. Paris, Doin ed, 1903 27. Vesalius A. De humani corporis fabrica [Atlas of the human body]. Basel, 1543, Biblioteca del Escorial 28. Servetus M (Michael Servet). Christianismi Restitutio [Restitution of the Christianism]. Viena del Delfinado, Balthasar Arnollet, 1553 29. Harvey W. Exercitatio anatomica de motu cordis et sanguinis in animalibus [An anatomical study on the movement of the heart and blood in animals]. 1628, translated by Leake CD. Springfield, CC Thomas, 1941 30. Fragoso J. Cirugía Universal [Universal Surgery]. Alcalá 1606, Madrid 1627: Viuda de Alonso Martín, 1627 31. Casserius, J. Pentaestheseion [All five sensorial organs].Venice, N Misserinum, 1609 32. Casserius J. Tabulae Anatomicae [Anatomical tables] Venice, E Deuchino, 1627. (Published post-mortem) 33. Descartes R. Les passions de l´âme [The passions of the soul]. Paris, Henry Le Gras, 1649. art. 128 to 133 34. Stenonis Nicolaus (Niels Steensen). Observationes Anatomicae. Section: De glandulis oculorum [Anatomical observations. On the small glands of the eyes ]. Leyden, 1662 35. Meibomius H. De vasis palpebrarum novis epistola [New chart about the vessels of the lids]. Helmstädt Germany, Henning Müller, 1666 36. Janin J. Mémoires et observations anatomiques, physiologiques et physiques sur l’œil et sur les maladies qui affectent cet organe [Anatomical, physiological and physical recollections and observations about the eye and the diseases that affect this organ]. 1772, Lyon, Libr Perisse & Paris, Didot 37. Lavoisien JF. Dictionnaire portatif de médecine,

d’anatomie, de chirurgie, de pharmacie, de chymie, d’histoire naturelle, de botanique et de physique. [Portable dictionary of medicine, anatomy, surgery, pharmacy, chemistry, natural history, botany and physics]. Paris, Libr T Barrois, 1793, p 315-6 38. Zinn JG. Descriptio anatomica oculi humani iconibus illustrata [Anatomical description of the human eye, illustrated with figures]. Goettingen, BA Vandenhoeck, 1755, 1780 39. Rosenmüller JC. Partium externarum oculi humani. Organorum lacrymalium descriptio [On the external parts of the human eye. Description of the lacrimal organs] Leipzig, 1797 40. Fallopius G. Observationes anatomicae [Anatomical observations]. Venice, MA Ulmum, 1561, and Köln, Inher, A Birckmanni, 1562 41. Wrisberg HA. Observationes anatomicae de quinto pare nervorum encephali et de nervis qui ex eodem duram matrem ingredi falso dicuntur [Anatomical observations of the trigeminus nerve and of the nerves that erroneously are said enter from the dura mater] Göttingen, JC Dieterich, 1777, 1791 Secondary sources providing additional information from references 2, 9, 10, 11 and 14. 42. Hirschberg J. Geschichte der Augenheilkunde, 1889. Translation of Blodi FC. The history of ophthalmology in antiquity. Bonn,Verlag, JP Wayenborgh, 1982, pp. 10, 15-18, and 178 note 860 43. Dollfus MA. L’ophtalmologie dans l’ancienne Egypte [Ophthalmology in Ancient Egypt]. L’Ophtalmologie des Origines à nos Jours, Annonay, Lab Faure, 1973;1:9-25 44. Murube J. History of Dakryology, in: Holly F (ed). The preocular tear film in health, disease, and contact lens wear. Lubbock (TX), Dry Eye Institute, 1986, pp 3-30 45. Magnus HF. Die Augenheilkunde der Alter [Ophthalmology in Antiquity]. Breslau, Kern 1901. Translated to English by Waugh RL, and published by JP Wayenborgh; Ostend, 1998. Vol I, pp 56-57, 123, 144, 147-148, 199, Vol. II:315-316 ,342 46. Lyons AS, Petrucelli RJ. Medicine. An illustrated history. New York, Ed Abrams Inc, 1978. Spanish translation: Historia de la Medicina. Barcelona, Ed Doyma, 1984, p 440 47. Ideler JL. Physici et Medici Graeci Minores, vol. 1. Reimer, Berlin, 1841, pp 144-67. English translation of the ancient Greek text by AA Diamandopoulos, Amsterdam, Hakkert, 1963 48. Pensier P. Histoire de l’Ophtalmologie [History of Ophthalmology], in Lagrange F, Valude E. Encyclopedie Française d’Ophtalmologie, vol 1. Paris, Doine, 1903, pp 3,11

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