Nicholas Carter 
Great Diamond Syndicate, Or, The Hardest Crew On Record [EPUB ebook] 

Excerpt: ""Your uncle murdered! It seems incredible!" Nick Carter leaned back in his chair and looked at his visitor, dismay showing in his face. "It is too true, old friend, Uncle Alvin was murdered in his bed last night, and diamonds to the value of half a million dollars stolen from the house." The speaker, Charley Maynard, was greatly excited. He was a young man who had arrived at legal age only a few months before. Almost from boyhood he had been a friend of the man of whom he now sought sympathy and advice. "Half a million in diamonds!" echoed the detective. "I was not aware that Alvin Maynard possessed diamonds to that value.""