My parents are asking me to help them find out some information on the value of an antique they have. The man I linked in this article was the first person to travel around the world via commercial means. He took videos of his travels, including the diamond mines in Africa, and also wrote a book about it. This is in the 1920's and 30's. They have those original reels and a signed copy of the book. They also own his house. Any help would be greatly appreciated! How much would something like this be worth, and how would you go about selling it?