To observe activities in a meat-packing plant, he hired detectives, by this he made it easier for him to get the material and details necessary to write this book.
Californian author and social activist Upton Sinclair is credited with creating the genre of journalism known as "muckraking." His best-known book, "The Jungle," exposed the disgusting and filthy working conditions in the meatpacking industry.
Thus, To observe activities in a meat-packing plant, he hired detectives
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