Galeazzi, Domenico Gusmano
Galeazzi, Domenico Gusmano
Galeazzi, Domenico Gusmano
(b. Bologna, Italy, 4 August 1686; d. Bologna, 30 July 1775)
Galeazzi (sometimes wrongly called Galeati), of whose background little is known, attended the Jesuit College in Bologna and studied medicine with the physician Matteo Bazzani, who is supposed to have discovered the coloring of bones in animals fed with madder root. He learned anatomy in the atmosphere created by Antonio Maria Valsalva, who in 1705 was named professor of anatomy at Bologna.
Galeazzi was graduated Doctor of Philosophy and Medicine in 1709 and took up science under the influence of Giacomo Bartolomeo Beccari, then professor of physics at Bologna. He was immediately appointed substitute lecturer in experimental physics; in 1734, when Beccari transferred to the chair of chemistry, Galeazzi succeeded him as professor of physics. His first published work in physics dealt with the construction of mercury thermometers.
In 1714 Galeazzi visited Paris, where he met Jacques Cassini, Louis Lémery, Malebranche, Réaumur, and other men of science and attended meetings of the Académie Royale des Sciences. During those meetings he became interested in the debate between Claude Geoffroy and Lémery concerning the significance of microscopic iron particles in living organisms: Geoffroy contended that these particles were produced by the organism, while Lémery asserted that they had been assimilated. On his return to Bologna, Galeazzi conducted experiments and demonstrated through chemical analysis that the iron particles were assimilated by the organism. He then made a systematic study to discover the connection between the iron in living organisms and iron salts in the soil. Later, in 1746, Galeazzi first ascertained the presence of iron in the human blood; his pupil Vincenzo Menghini detected whole hematic iron in erythrocytes.
In 1716 Galeazzi was appointed professor of philosophy at Bologna, a post he held for forty years. In 1719 he made geological observations in the Emilian Apennines. Later, in entomology, he discovered the endophagous generation of the fly and the oviparous generation of a cochineal, Pulvinaria vitis (L.). Galeazzi also had a successful medical practice and wrote on the use of Peruvian bark (cinchona), on jaundice, and on gallstones and kidney stones. He is remembered today primarily for his anatomical research.
Galeazzi began his anatomical work in 1711, when he observed corpora lutea in different stages of regression in pregnant women; but his most important anatomical discoveries were in the gastrointestinal system. He defined the positions of the three layers of muscle fibers in the stomach and described the peculiar arrangement of the superficial layer of longitudinal muscle fibers. He described two layers of muscle fibers in the small intestine: the interior circular and the external longitudinal; in the colon he considered only the circular layer important, because the external layer of longitudinal fibers forms only three longitudinal bands.
In the mucous coat of the intestines Galeazzi described the glands now called Lieberkühn’s glands. Johann Nathanael Lieberkühn described them in 1745; Galeazzi made his observations in 1725 and published them in 1731. The existence of intestinal glands had already been claimed by Malpighi (1688), the villi of the small intestine had been described by Gaspare Aselli, and Thomas Bartholin had studied the villi in connection with the chyliferous vessels. In Galeazzi’s time the question was whether the villi were hollow siphons, spongy perforated papillae, or unperforated papillae. Galeazzi clarified the structure of the villus: it can be long and cylindrical or short and squat, but he denied the existence of any free lymphatic opening on its surface.
Galeazzi discovered many minute pores not on the villi but between them, distributed over the entire intestinal surface. He concluded that a special sievelike membrane exists on the interior surface of the intestines and that each of these numerous pores is an opening of a glandular structure in the intestinal wall. Galeazzi also wrote that these glandular structures discharge a secretion into the intestinal cavity.
In 1756 Galeazzi retired from teaching philosophy; although he was a distinguished anatomist, Galeazzi never held the chair of anatomy. He died at the age of eighty-eight and was buried in the Church of the Confraternity of St. Philip Neri in Bologna.
I. Original Works. Galeazzi’s writings include “De muliebrium ovariorum vesiculis,” in Commentarii de Bononiensi Scientiarum et Artium Instituto atque Academia, 1 , pt. 2 (1731), 127–130; “De calculis in cystifellea repertis,” ibid., 354–358; “De cribriformi intestinorum tunica,” ibid. 359–370; “De ferreis particulis quae in corporibus reperiuntur,” ibid.,2, pt. 2 (1746), 20–38; “De thermometris Amontonianis conficiendis,” ibid., 201–209; “De carnea ventriculi et intestinorum tunica,” ibid., 238–243; “De insecto quodam in vite reperto,” ibid., 279–284; “De moscho,” ibid., 3 (1755), 177–193; “De morbis duobus,” ibid., 4 (1757), 26–43; “De renum morbis,” ibid., 5 (1757), 139–150, 249–260; “De cortice peruviano,” ibid., 216; and “De sudore quodam atque urina colore nigerrimo infectis,” ibid., 6 (1783), 1–12.
II. Secondrary Liteature. On Galeazzi or his work, see A. Corti, “L’anatomico bolognese Domenico Gusmano Galeazzi e la sua esauriente descrizione delle ghiandole intestinali che molti dicono di Lieberkühn,” in Archivio italiano di anatomia e di embriologia, 19 (1922), 407–434; and “Note storiche e biografiche su Bologna e il suo Studio,” in Rivista di storia delle scienze mediche e naturali, 40 (1949), 19–51; J. N. Lieberkühn, Dissertatio anatomicophysiologica de fabrica et actione villorum intestinorum tenuium hominis (Leiden, 1745); M. Malpighi, “De structura glandularum conglobatarum,” a letter to the Royal Society (1688), in Marcelli Malpighii opera posthuma (London, 1697), pp. 152–165; M. Medici, Compendio storico della scuola anatomica di Bologna dal Rinascimento a tutto il secolo XVIII (Bologna, 1857), 256–272; and V. Menghini, “De ferrearum particularum sede in sanguine,” in Commentarii de bononiensi scientiarum et artium instituto atque academia, 2 , pt. 2 (1746), 244–266.