Jack London 
The People of the Abyss [EPUB ebook] 

A masterpiece of reportage,
The People of the Abyss is a riveting first-hand account of Jack London’s life on the streets in the East End of London in 1902.  The writer lived in homeless shelters incognito for weeks, recording his experiences of life there. The book caused a sensation when first published and brought the author of
White Fang and
The Call of the Wild high critical acclaim.