Strong coffee, whiskey, or other potent drink (1890s+)
Already twenty barrels of embalming fluid have been consumed, aggregating 800 gallons.
In those specimens injected with embalming fluid, the body cavities were injected with formalin.
The embalming fluid contains some of the elements not found in our world, but this is not the total secret.
All specimens were kept in containers filled with embalming fluid.
Hair often lengthens after the death of a person, if no embalming fluid has been injected.
Four men lift the corpse on a rude table, and there it is thoroughly washed and an embalming fluid injected in the arm.