About the book (from wikipedia):

James Bruce (1730 – 1794) was a Scottish traveller and travel writer who spent more than a dozen years in North Africa and Ethiopia, where he traced the origins of the Blue Nile.

A multi-volume account by the Scottish traveller James Bruce of his journeys in the Horn of Africa, which includes an eye-witness account of Ethiopian history and culture, as well as a description of that country and the neighboring kingdom of Sennar and the Ottoman province of Habesh.

Bruce and his sensational stories were received with incredulity upon his return to London in 1774 after more than a dozen years of travel in North Africa and Abyssinia (Ethiopia) where he traced the Blue Nile.

His Travels was issued in 1790, after he retired to his home at Kinnaird, at the urging of his friend Daines Barrington. It was published in five octavo volumes, lavishly illustrated, but was ridiculed by scholars and other travellers as being exaggerated nonsense. An example of the criticism his account received would be the comments of Henry Salt, who after visiting Ethiopia and interviewing a number of inhabitants who knew him, wrote:

The most material points (besides those noticed in a former part of this work) which affect Mr. Bruce’s veracity, are those, of his never having received any district or command; his not having been engaged in the battles of Serbraxos – the overthrow of his pretensions to an almost intuitive knowledge of the languages of the country – his mis-statements respecting Guanguol, Amha Yasous, and the living feast, and the unpardonable concealment of the fact, that [the artist Luigi] Balugani attended him on his journey to the sources of the Nile.

However, the substantial accuracy of his Abyssinian travels was later confirmed by explorers who included William George Browne and E.D. Clarke, and it is considered that he made a real addition to the geographical knowledge of his day.