""The Journal of a Tour into the Territory Northwest of the Allegheny Mountains, Made in the Spring of the Year 1803"" is a book written by Thaddeus Mason Harris. The book is a detailed account of Harris' journey through the Northwest Territory in the United States in the early 19th century. Harris was a minister and historian, and his journal documents his observations of the landscape, people, and culture of the region. The book is divided into...