First edition of one of the most important books on cancer – the modern classic on tumours. The work was never completed; it has only twenty-five lectures instead of thirty mentioned in the title. The twenty-fifth lecture records one of Virchow’s mistakes, his erroneous conclusion that the origin of cancer is in the connective tissue. This theory of the connective-tissue origin of carcinoma was almost immediately refuted in a paper appearing in Virchow’s Archiv. Therefore the monograph remained unfinished, probably because doubts had arisen in Virchow’s mind regarding the origin of epithelial tumours from reserve cells in the connective tissues. Virchow’s classic work on tumours is sometimes considered even more important than his famous Cellularpathologie (1858). The engraved frontispiece plate is drawn from a photograph. Collation: Vol. I: pp. xii, 543, (1), with one engraved frontispiece plate (after a photography); vol. II: pp. x, 756; vol. III; part 1: pp. (2), 496, with one engraved plate. Together 243 wood engravings in the text. Binding: Three volumes, contemporary half calf. References: Garrison-Morton 2617; Garrison, History, Major, Classic Descriptions of Disease, 508 ff.; Risse, Günther B. in DSB, XIV, pp 39-44; Wilson J. Walter, ‘Virchow’s Contribution to the Cell Theory’ in Journal of the History of Medicine, II (1947), pp 163-178; R.J. Rather, The Genesis of Cancer (1978), pp 100-104 and 128-154; See SLS 500. Waller 10001.