Born at Bahia, in Brazil, on March 4th, 1863; he was the second son of Emilie Kanthack, at one time British Consul at Pará, Brazil. As a child he was somewhat weakly, and his sole recreation was swimming, but, coming with his family to England in 1881, he became an athlete and in time an excellent football player. His family had arrived in Europe as long ago as 1869, and he was at school in Germany from 1871-1881, first at Hamburg and then at gymnasiums at Wandsbeck, Lüneburg, and Güterslok. In 1881 he went for a few months to the Liverpool College. Up to his fifteenth year he seems not to have been a brilliant schoolboy, but he then began to develop mentally and, on finishing his school studies, to show the intellectual mastery of subjects which so signally characterized him during his short life. He became a student of University College, Liverpool, in 1882, and, matriculating at the University of London, passed the successive examinations with honours. He came to London and entered St Bartholomew's Hospital in 1887, and in 1889 worked under Virchow, Koch, and Krause in Berlin, adding to his reputation as an able and indefatigable student a character for accurate observation and original thought in the field of research. Virchow would not allow him to neglect his clinical work, although he devoted himself more particularly to bacteriology and pathology. He made many friends among the professors, chief of whom was Virchow, as well as among fellow-workers. Returning from Berlin in 1890, he served as Obstetric Resident under Matthews Duncan at St Bartholomew's Hospital. While holding this position he, together with Beaven Rake and Buckmaster, was appointed by the Royal Colleges of Physicians and Surgeons and the Executive Committee of the National Leprosy Fund to inquire into and report on the extent to which leprosy prevailed in India - its pathology and treatment - and to suggest measures for dealing with leprous subjects. The report was on many points of a negative character. The most important conclusions were that: (1) There were some grounds for believing that a gradual decrease in the number of lepers was taking place; (2) Direct contagion was at the most a very small factor in causing the spread of leprosy; and (3) Compulsory segregation of lepers was not advisable. A special committee appointed to consider the report refused, with some exceptions, to accept these conclusions, which were directly opposed to many of the alarmist reports current in England when the National Leprosy Fund was started. The Commissioners' conclusions, however, were endorsed by the medical members of the Executive Conunittee, and were in accordance with the views held by the Indian Government. Kanthack, on his return from India in 1891, matriculated at Cambridge as a Fellow Commoner of St John's College, and was at the same time appointed John Lucas Walker Student in Pathology. He resumed his researches and wrote on immunity, his most important paper on this subject, written in conjunction with W B Hardy, being published in the *Proceedings of the Royal Society* (1893, lii, 267): "On the Characters and Behaviour of the Wandering (Migratory) Cells of the Frog, especially in Relation to Micro-organisms." Coming at a time when the wholly phagocytic theory of Metchnikoff was beginning to be questioned, and the supporters of the humoral theory were in their turn beginning to claim more than their share, it demonstrated the impossibility of making either theory explain all the facts, and pointed out that neither theory, even if proved, would bring us any nearer the true understanding of immunity. Another paper published by him at Cambridge dealt with mycetoma, and following Vandyke Carter, proved the disease to be parasitic in nature, the parasite being closely allied to, if not identical with, actinomyces. He left Cambridge in 1892, and began to practise as a physician in Liverpool. He was appointed Medical Tutor and Registrar at the Royal Infirmary as well as Senior Demonstrator of Bacteriology, a post specially created for him, and Medical Tutor at University College, Liverpool. He suffered from a severe attack of typhoid fever in 1894, but in spite of this he won the Jacksonian Prize in 1895, his essay being entitled, "The Aetiology of Tetanus and the Value of the Serum Treatment". The MS, illustrated with photographs, etc, is in the Library and bears the motto:- "What are these So withered and so wild in their attire: That look not like the inhabitants o' the earth And yet are on't?" - Macbeth, Act I, Sc 3. A microphotograph of the bacilli is pasted immediately underneath the motto. He soon returned to St Bartholomew's as Director of the Pathological Department in the school and hospital, and here he remained till he was appointed Professor of Pathology at the University of Cambridge in 1897. At the same time he was Lecturer at St Bartholomew's on Pathology and Bacteriology, and Curator of the Museum. Clinical material, hitherto examined in the wards, now came to his department, and in the course of a year amounted to many hundreds of specimens. He read short and often very valuable papers at the meetings of the Pathological Society, which he attended regularly. He acted as Deputy to Professor Roy, of Cambridge, during the illness of the latter in 1896, travelling to and from St Bartholomew's and the University. In the spring of 1897 he went to reside in Cambridge and was given an honorary MA and elected a Fellow of King's. He succeeded Roy in the autumn as Professor of Pathology. During the autumn of 1898 the report of his research on the tsetse fly, conducted by him in conjunction with Messrs Durham and Blandford, was published while he was suffering in his last illness. This report cleared the ground for further investigation of what was then known as tsetse-fly disease, although no method of prevention or cure was yet propounded. His last work, published in conjunction with Dr Sladen, reported on tuberculous milk. Kanthack was very popular, and for solid reasons. Although his teaching attracted every class of men, it was doubtless his love of field sports that brought him in the first instance into touch with many of his most devoted pupils. His influence on younger men was remarkable, and he seemed able to get work that was creditable to both master and pupil out of the most unpromising material. He kept up a very large scientific correspondence, chiefly on pathology, and his correspondents were in all parts of the globe. He died at Cambridge of malignant disease on December 21st, 1898. A sum of money was collected after his death which was devoted to establish 'The Kanthack Memorial Library' in the Pathological Institute of St Bartholomew's Hospital. He married in 1895 Lucie, daughter of F Henstock, of Liverpool, who survived him. Kanthack was fortunate in the opportunity of his life. He began his career as a pioneer in bacteriology and was permitted to take a wide outlook over a new science. His social qualities attracted many pupils, and enabled him to found a school in London and to carry on in Cambridge the work begun by Roy. He was both interesting and informative as a lecturer; with a soft and lisping speech, he had the artistic power to illustrate his words with excellent sketches on the blackboard. In his teaching he was somewhat dogmatic, but never so much as to prevent his pupils from thinking for themselves; indeed, his dogmatism appears to have had for its object the awakening of a desire for discussion in those to whom he was addressing himself. He soon marked any flaw in experiment or argument, and was always ready to set his pupils to work on subjects which required further elucidation, or the gathering of facts and information on the problems which he was himself investigating. Modest and unassuming in manner, his knowledge often routed the more aggressive type of student with repartee which though delivered quietly and good-humouredly was none the less deadly. He was thoroughly versed in contemporary pathological literature and was well read in general literature outside his profession. With a fine memory, he was rarely at a loss for an apt quotation or illustration. There is a good portrait from a photograph in the *St Bartholomew's Hospital Journal* (1899, vi, 51). Publications:- A bibliography compiled by Charles R Hewitt is to be found in the *St Bart's Hosp Jour*, 1899, vi, 51.