This book by Tymstra (agriculture and forestry, Government of Alberta) combines an analysis of the largest complex of wild land fires recorded in North America with a compelling narrative of the human response.  Like other fire-dependent ecosystems, the boreal forests of northern Canada and Alaska require fire for regeneration.  Some of the largest fires on Earth occur in these boreal forests yet get little public attention.  In 1950, a combination of conditions and human actions (campfires, fires to clear vegetation for agriculture) led to the Chinchaga firestorm in Alberta.  It spread smoke to the east coast of North America from Florida to Newfoundland, creating a phenomenon that caused the sun and moon to appear blue in color.  The analysis presents data in tables, charts, graphs, and maps, illustrating the causes and effects of the firestorm.  The narrative presents the human dimension of firefighting, the frustration of inappropriate policy and a distant bureaucracy, and the innovative (often in defiance of policy) tactics in responding to wild land fire.  This work is an amazing scientific contribution to fire science, ecology, public policy, human geography, and Canadian history.  It is a great story for general readers as well. Summing Up: Highly recommended. All readership levels.