Death has removed from our midst Colonel Anderson McKendrick, a well-loved personality in Edinburgh. This is a character not apparent in the simple record of his titles but is a precious and lasting possession of his many friends and acquaintances. Son of the Professor of Physiology in Glasgow, he would have wished in earlier days to have followed in the footsteps of his father in an Indian sphere, but his service became otherwise directed. These directions, so far as they can be summed up shortly, were to the study of malaria, rabies, and immunity, which were excellent introduction to later work on mathematical epidemiology. The medical men who have occupied themselves in attempting to bring validity into medicine by mathematical methods, and particularly by the use of the Pearsonian calculus, are still sufficiently few to justify for McKendrick the name of pioneer in this type of research. The probability of an event may be studied mathematically and, in the absence of direct, non-permissible experiment, becomes a most important means of transforming medicine from an art into a science. There are those in our profession who scoff at this approach, but the answer given by McKendrick himself to the eminent scientific physician Sir James Mackenzie serves to refute such criticism. "Your magnification of 'experience,' sir," he said, "is itself testimony to a well-ordered, though subconscious, statistical arrangement of your data." The old man accepted the explanation; indeed he had probably always accepted it, for he had established a statistical record department in his own Institute. The opposition to a statistical approach to medical experience and to the establishment of significance of results seems based on the disappointment which has come to many an enthusiast who consulted what became known elsewhere than in Edinburgh as the "wet blanket department." McKendrick's kindliness would never allow the chill to be a shock, for he always tried to provide a stimulus to greater perfection.
In his student days McKendrick made contact in his father's house with men like Lord Kelvin, Sir James Dewar, and Sir William Ramsay. A remark of Lord Kelvin's which he was fond of quoting was, if memory can be relied on, that many "Laws of Nature" seemed to him to be simply "mnemonics." Whether it was in these early days that he received his bent towards mathematics is hard to say. It certainly was not in Jena, where he studied mainly embryology, physiology, and anatomy under Biedermann, Fürbringer, and Braus. In Germany he lived with the Zeiss family. Perhaps he may have received an early impetus towards mathematical study from Sir Ronald Ross when he accompanied him to report upon anti-malarial operations in Sierra Leone. At an early stage in his career his reading took this turn when, as civil surgeon of the Nadia district of Bengal, he lived with the engineer building an important bridge over the Ganges river. At all events he arrived on appointment to the Pasteur Institute of India, Kasauli, with a well-perused copy of Perry's Calculus for Engineers. The next two years saw this type of study continued, with resort to the textbooks of Mellor on Higher Mathematics and Chwolson's Traité de Physik.
His leave years were occupied still on these unusual subjects: physical chemistry in Glasgow under Soddy in 1907, and mathematics in 1913 under Professor MacDonald, Aberdeen, who wrote: "The importance of adequate mathematical equipment in certain fields of medical research is now recognised, and McKendrick is by training and experience eminently qualified to carry out or superintend the carrying out of such researches."
McKendrick became a Fellow of the Royal Society of Edinburgh in 1912, but it was not till after his appointment in 1920 to be Superintendent of the Royal College of Physicians' Laboratory that his connection with the Society became more official and active. Among his early papers were one (1909) to the Royal Society, London, on the "Chemical Dynamics of Scrum Reactions," and another (1916) to the Indian Journal of Medical Research on "Applications of the Kinetic Theory of Gases to Vital Phenomena." These two papers give some indication of his mode of approach to the problems of immunology and epidemiology.
Those who hold such posts as McKendrick did in Edinburgh come as a rule to serve on committees. Some of these were promoted by the Royal College of Physicians. A committee meeting which he attended regularly for a time was that of the Scottish Board of Research in Veterinary Science, where his advice on modes of investigation, into epizootics instead of epidemics, was of much value to his colleagues. McKendrick's influence over his staff was benevolent and fraternal as well as scientifically directive. His retirement, necessitated for health reasons, was unwillingly accepted. He was a clear thinker in policy and a good administrator. In the short period of retirement allowed to him he remained actively concerned for the interests of those who surrounded him in a Speyside village. Truly he was a friend of man.
He died on May 30, 1943.