Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Why is John Harrison such a lesser-known scientist?

I never heard of John Harrison, or really thought of how difficlt it must have been to accurately calculate longitude until I read this book. But there is more to the story of longitude than mathematics and engineering. The human story of longitude is brought to life in Sobel's Longitude.Sobel does a very good job of explaining the intracies of the longitude problem, and relates the personal trials and frustrations of Harrison with a penchant for his personal fortitude and courage in the face of frustration and humiliation. I found her writing of the story to be truly inspiring.The book without a doubt is a "personal interest" story, with only a minimum of explaination of how the timepieces actually functioned and the challenges their developement involved. To others, this evidentially detracted from the book - I disagree.