Rowland worked in India and helped confirm how plague is spread by rats carrying fleas, and later joined the Royal Army Medical Corps in the First World War as a bacteriologist in France, where he worked on septic wounds, typhoid carriers and gas gangrene, and set up No.

[4] Rowland's career began in medical journalism while he was still a medical student when, in 1896, as Hart's intern, the year following the discovery of X-rays,[6] the BMJ appointed Rowland as "Special Commissioner" to produce a report on the clinical use of X-rays titled "Report on the Application of the New Photography in Medicine and Surgery.

[3][6] In the preface to the first issue, written in April 1896, he wrote that "the object of this publication is to put on record in permanent form some sort of the most striking applications of the new photography to the needs of medicine and surgery".

[6] He coined the term "skiagraphy" to describe the making of X-ray pictures and wrote some of the early works on radiology.

[3][4] In 1905, the Lister sent him to India to investigate and confirm the theory that plague is spread by rats carrying fleas.

[4][8] In 1915 he rose to the rank of Major and worked with the 26th General Hospital Royal Army Medical Corps.