Captain America: First Avenger shows the superhero waking up after being frozen in Arctic ice for 70 years. This iconic moment feels like a modern sci-fi marvel, but it actually has roots stretching back to the 19th century. The idea of suspending life through freezing and then reviving it is not new. It appears in early science fiction, including a short story from 1845 called Hilda Silfverling by Lydia Maria Child. This story explores the concept of cryptopreservation long