It's genuinely rare these days to come across a so-called "medical miracle." Yet back in the early 1900s, the case of Adam Rainer's strange and miraculous growth stunned physicians. Rainer is the only person in recorded history to have been both legally a dwarf and a giant. Rainer was born in Graz, Austria, in 1899. He was a normal, healthy child by all accounts. Despite being born to parents of normal height, by the time that World War I broke out, Rainer stood at just 4 feet, 6 inches. Recruiters told him he was too short and weak to join...