From Guy Deverell (1865) by Sheridan Le Fanu - an early mention of cryonics:
“But there’s another process, my uncle, Monsieur Varbarriere, says, by slow refrigeration: you are first put to sleep, and in that state frozen; and once frozen, without having suffered death, you may be kept in a state of suspended life for twenty or thirty years, neither conscious, nor growing old; arrested precisely at the point of your existence at which the process was applied, and at the same point restored again whenever for any purpose it may be expedient to recall you to consciousness and activity.”