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Baillou, Guillaume De

Baillou, Guillaume De

also known as Baillon and Ballonius

(b. Paris, France, ca. 1538; d. Paris, 1616)


Baillou was the son of a mathematician and noted architect. He became a physician in 1570 and dean of the Faculty of Medicine in 1580. He had a reputationn for dialectics and was known as “the bane of the bachelors,” but he also was the most erudite and well-read doctor of his time—famous for his eloquence, the clarity of his courses, and his writings, almost all of which were published posthumously. Baillou fought against the tradition of Arab medicine and revived the Hippocratic tradition of clinical observation, human understanding, and macrocosmic concepts of illnesses and their treatment. consequently, he thought that solar eclipses and the position of the stars were important in medical practice, and restored a little of the astrology completely eliminated by Jean Fernel—whose pupil he never was, despite claims to the contrary.

During the many epidemics in Paris between 1570 and 1579, Baillou developed the idea of the ephemerides, which influenced the work of Thomas Sydenham. He was thus the first occidental epidemiologist since Hippocrates. He left excellent descriptions of the plague (and possibly of typhoid fever); of measles, which he distinguished from variola; and of diphtheria, whose choking false membranes he identified. Baillou is also credited with the first mention of adhesive pericarditis complicated by edema, and of whoooping cough (tussis quinta). The latter is uncertain, however, for whooping cough seems to have been diagnosed in the khulasat-ul Tajjarib (1501) of Baja’-ul-Douleh, an Iranian doctor.

Baillou brought rheumatism into nosology, and in this connection he gave a learned presentation of Fernel’s, Lepois’s, and Felix Platter’s rather vague conceptions of the overflow of phlegm and aqueous humors. Fernel thought the distillatio was a superfluous humor running down from the head into the declivitous parts of the human organism and was the sole cause of chronic arthritis and crural neuralgia. He had located these ailments, two hundred years before Domenico Cotugno, in the sciatic notch, which was the seat of the diffusion of pain. Baillou attributed to rheumatism all pain in the external habitus corporis, that is, all areas situated between the skin and the internal parts of the body. The habitus corporis therefore included cellular tissues, muscles, tendons, aponeuroses, bones, and joints. He went on to describe a rheumatic diathesis (not necessarily articular) with painful localizations in the limbs. This was in the form of gout, sciatica, and arthritis or morbus articularis (rheumatic fever or subacute or chronic rheumatism). To this infinitely variable disease Baillou related all pains of the external body, from scurvy, smallpox, and lead poisoning to those thought to be caused by wind, worms, and other obscure agents.


I. Original Works. Baillou’s writings are Comparatio medici cum chirurgo and castigandum quorumdam chirurgicorum audaciam (Paris, 1577); Consiliorum medicinalium libri duo (Paris, 1635-1639), also published separately (Vol. II only) by Jacques Thèvart (Paris, 1640); Definitionum medicinalium liber (Paris, 1639); De convulsionibus libellus (Paris, 1640); Epidemiorum et ephemeridum libri duo(Paris, 1640), also in Ralph Mayor, Classic Descriptions of Disease (Lawrence, Kans., 1932), pp. 94-96, 159-160, and translated into French by Prosper Yvaren as Epidèmies et èphèmèrides (Paris, 1858), Liber de rhumatismo et pleuritide dorsali (Paris, 1642), trans. by Barnard in British Journal of Rheumatism, 2 (1940), 141-162; Commentarius ad libellum Theophrarsti de Vertigine. De virginum et mulierum morbis liber (Paris, 1643); Opuscula medica de arthritide, de calculo et urinarum hypostasi (Paris, 1643), Adversaria medicinalia (Paris, 1644), Opera omnia medica, 4 vols. (Paris, 1685), also Tronchin, ed., 4 vols (Geneva, 1762).

II. Secondary Literature. Works on Baillou are A. Chèreau, “Baillou,” in Dictionnaire encyclopèdique des sciences mèdicales, VIII (Paris, 1878); A. Delpeuch, Histoire des maladies—La goutte et le rhumatisme (Paris, 1900); Charles Fiessinger, La thèrapeutique des vieux maîtres (Paris, 1897), pp. 110-115; E. W. Goodhall, “A French Epidemiologist of the Sixteenth Century,” in Annals of Medical History, 7 (1935), 409-427, and “De Baillou Clinician and Epidemiologist,” in Journal of the American Medical Association, 195 (1966), 957; and Philippe Very, “II y a 350 ans mourait Guillaume de Baillou,” in Scalpel, 119 (1966), 677-678.

Pierre Huard

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