Preliminary Report on Gowganda Mining Division, District of Nipissing, Ontario is an authoritative early 20th-century geological survey authored by W. G. Miller, published by the Ontario Bureau of Mines. This comprehensive report provides an in-depth examination of the Gowganda Mining Division, located in the District of Nipissing, Ontario, during a period of burgeoning mining activity. The book meticulously documents the region's geological formations, mineral resources, and mining prospects, with a particular focus on the discovery and development of silver and cobalt deposits that spurred a mining rush in the area. The report is structured to guide both professional geologists and mining investors, offering detailed descriptions of the local topography, rock types, and structural geology. It includes observations on the distribution and characteristics of ore bodies, the nature of the host rocks, and the processes that led to mineralization. The author provides valuable insights into the methods of exploration and extraction employed at the time, as well as assessments of the economic potential of various mining claims and properties. Richly illustrated with maps, diagrams, and photographs, the book captures the landscape and mining operations of early 1900s Northern Ontario. It also discusses the challenges faced by prospectors and mining companies, such as transportation, infrastructure, and environmental conditions. The report serves as both a scientific document and a historical record, reflecting the optimism and ambition of Ontario's mining frontier. Preliminary Report on Gowganda Mining Division, District of Nipissing, Ontario remains a significant resource for historians, geologists, and anyone interested in the development of Canada's mining industry, offering a window into the exploration and exploitation of one of Ontario's most promising mineral districts at the dawn of the 20th century.