The Asphyx

In Victorian England, scientist Sir Hugo Cunningham is a part of a parapsychological society that studies psychic phenomena. The society concludes that they have captured evidence of the soul escaping the body. Cunningham theorizes that some property of the energy released by the combination of phosphorus and water renders the asphyx immobile. If correct, this would mean that an individual would be immortal so long as their asphx remained imprisoned. Cunningham commissions the construction of an impenetrable vault door on his family tomb, with a complex combination lock as the only means of opening it.