In 1890, City of Halifax staff, probably from the Board of Health, marked the location of cases of diphtheria in colour on this plan. The 1891 Report of the City Medical Officer, Dr. Thomas Trenaman, indicated that there were 192 deaths from diphtheria in 1890—the leading cause of death that year. Infectious diseases have always been a serious public health issue; the City of Halifax operated an Infectious Diseases Hospital in the North End, beside Rockhead, the City Prison.
The City of Halifax created similar maps locating typhoid cases during the outbreak of 1913–1914.
The base map on which staff marked the locations of diphtheria, is a print from a wood-cut done by xylographer C.H. Flowerelling. Before establishing its own mapping service (now HRM’s Geographic Information Systems and Services) the city government used published maps for its mapping needs. Note that the lines of radius indicate distance from the Post Office (P.O.).
This map is one of over 12,000 plans filed with the City Engineer's Office. The Municipal Archives is refining a database of these plans so that it will eventually be searchable by the public. Even now the public can search and view these plans at the Archives.