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John Bruce MacCallum

John Bruce MacCallum (1876-1906) was an American researcher at Johns Hopkins Medical School.


April 21, 1906. The British Medical Journal 955

John Bruce MacCallum, B.A., M.D.,

Associate Professor of Physiology in the University of California.

There will be widespread regret in scientific circles in the United States and Canada at the death of this talented young investigator, which took place suddenly at Berkely, California. Dr. MacCallum was the second son of the Medical Superintendent of the Asylum for the Insane, London, Ontario, formerly of Dunnville, and brother of Dr. W. G. MacCallum, Professor Welch’s associate in the Pathological Laboratory of the Johns Hopkins Hospital. After completing his scientific studies at the Toronto University, young MacCallum entered the Johns Hopkins Medical School, from which he graduated in 1900. While still an undergraduate, he began researches with Professor Mall, and made an exhaustive study of the arrangement of the muscle fibres of the heart, worked out from the embryological standpoint.

  • 1 Johns Hopkins Reports, vol. ix.

Then followed a very careful investigation on the microscopic structure of the heart fibres, particularly with reference to fragmentation. Appointed an Assistant in the Anatomical Laboratory, he devoted much time to histology and embryology, and published an elaborate paper on the development of the intestines.

At Leipzig, where he had gone to study, a tuberculous pleurisy interrupted his work; but after six months’ rest, he rallied and appeared quite well. Thinking that the Pacific coast would be better for his health, he accepted a position with Professor Jacques Loeb at the University of California. For eighteen months he was able to teach, and to follow out and to publish a most interesting series of investigations on the action of saline purgatives and on the influence of calcium and barium salts on the activity of the kidneys. In the winter of 1904-5 the tuberculous pleurisy again became active and the lung was attacked. He improved in Muskoka during the - gummer, and felt well enough to return to California in the autumn. The progressive sclerosis of the lung had, however, been followed by changes in the heart, and the end came in an attack of acute dilatation.

Dr. MacCallum had in rare degree the genius for investigation and for stimulating research in others. He was a true disciple of Ludwig, whose attitude towards problems in anatomy and physiology he had inherited from his teacher, Mall. Widely read in literature, with a sane outlook on all the problems of life, he had the mental and moral equipment necessary for a great teacher, and this intensifies the tragedy of his untimely death.

Short Years, the Life and Letters of John Bruce MacCallum

The Canadian Medical Association Journal Mar. 1938

Short Years, the Life and Letters of John Bruce MacCallum, M.D., 1876-1906. A. Malloch. 343 pp., $3.50. Normandie House, Chicago, 1938.

Damn the tubercle bacillus! Osler wrote of the subject of this fine memoir that he was ‘‘one of the most brilliant young men it has ever been my lot to teach. .. Alas! he succumbed suddenly, to the irreparable loss of science in America, He had a mind of singular acuteness, a clear judgment, and he had caught from Mall some measure of that investigating spirit that has made the anatomical school of John Hopkins University so famous. When the news reached me of his death, one morning as I sat at breakfast, I broke down in an irresistible paroxysm of regret and had to leave the table’’—one of the few occasions when Osler’s 2quanimitas failed him.

Son of the versatile Dr. G. A. MacCallum, of Dunnville and London, Ont., J. B., like his elder brother, W. G., the pathologist, was one of the large group of distinguished research workers, pupils of Ramsay Wright, which the University of Toronto contributed to Johns Hopkins in the ’90’s. During his short years at Baltimore and in California, under Loeb, where he bravely fought a losing fight against tuberculosis, he did pioneer work of permanent value on the embryology and histology of the heart muscle and the intestines, and on the action of calcium and the salines. His letters give an introspective picture of his student days, his work, his summers in Muskoka, his travels—to Germany, Jamaica, Denver (where he practised briefly) and California, and in addition they have a literary, romantic, and psychological interest. He was also an artist, musician, story-writer, and poet; and the few poems included make one wish that room had been found for more. The ‘‘Spirit of Death’’, when he conjured it, answered only too promptly:

Oh come, be swift and take me while I stand, My work still strong beneath a steady hand, A life that ne’er grew old!

As might be expected of the distinguished Canadian librarian of the New York Academy of Medicine, Dr. Malloch has skilfully handled his abundant material. It is that best kind of work, a labour of love, for MacCallum was a hero to him in his boyhood. The book is finely printed.


The National Library of Medicine Dr. John Bruce MacCallum


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