First edition of Rudbeck’s famous paper in which he announced his revolutionary discovery of the lymphatic vessels – a World classic in the literature of anatomy and physiology. It is of the most extraordinary rarity, especially considering its scientific significance. – ”We know of no copies in either North American or English institutional libraries; we understand that only three copies are known in Rudbeck’s native Sweden, and only one in Denmark, home of Rudbeck’s great rival Bartholin. This is a truly incredible census report for a medical book of such importance; we find it hard to recall any other instance of such rarity in a medical book of the first rank” (Jeremy Norman, Catalogue 17/448, with a preface to the catalogue, An Absolute Rarissimum, dealing with Rudbeck’s Nova exercitatio anatomica). In the fall of 1650, when he was 19 years old, Rudbeck reported on previously unknown vessels (lymphatic vessels) that carried a colourless fluid from the liver. At the same time, and independently of Pecquet, he discovered the thoracic duct, through which the lacteal vessels discharge chyle into the veins. He performed a number of systematic dissections and vivisections on dogs, calves, sheep, and cats, and was able in the following year, 1651, to elucidate the structure of this system and to demonstrate its connections with lymph glands. In April, 1652, Rudbeck demonstrated his anatomical discoveries, using a dog as his subject, before Queen Christina and her court at Uppsala. It might thus be considered that he had communicated them at this time, although he postponed publication. Instead, he published and defended an academic dissertation, De Circulatione sanguinis, under professor Olaus Stenius, said to have been Uppsala’s first Cartesian. Not until the summer of 1653 did he publish his work on the lymphatic vessels, a clear and convincing description of the newly discovered vessels and their course and valves, the upper glands, and the nature of the lymphatic fluid. Rudbeck later stated that he had used almost 400 animals in his numerous experiments. Collation: Pp (48), with 2 engraved plates by Rudbeck engraved by Magnus Celsius numbered Tab. I and Tab. II. Binding: Disbound. Printed on rather poor paper. Title-page soiled. References: Garrison-Morton 1098; Bibliotheca Rudbeckiana 664; Lindroth 'Harvey, Descartes, and Young Olaus Rudbeck’ in Journ. Hist. Med. Harvey Issue, XII, 2 (1957), pp 202-19; DSB, XI, 586-88; Facsimile edition (Uppsala, 1930); Hofsten 'Upptäckten av bröstgången och lymfkärlssystemet’ in Lychnos 1939, 262-88; English translation with a biographical note by Göran Liljestrand in Bull. Hist. Med. XI, 3 (1942), 304-39; Norman Library 1855; Hagelin, Rare and Important Books in the Library of the Karolinska Institute, pp 90-93; Jeremy Norman Catalogue 17, preface and item 448. Waller 8283.