This blog alleges that he wrote a book "The Man Farthest Down: A Record of Observation and Study in Europe" and that he devotes 5 chapters to child slavery, the blogpost makes several references to this book I want to verify if these claims are accurate. He used a great deal of emotive language and if this is accurate I'm curious what his overall analysis was or more about him. The claim suggests that he witnessed child slavery in Sicily and was horrified by it, and appears to have made it an element of a wider analysis and I'm curious about what his questions conclusions were.

http://www.iitaly.org/bloggers/1066/child-slavery-sicily-1910