How to Invent Everything: A Survival Guide for the Stranded Time Traveler

by Ryan North

Immediately after slaughtering the animals, lay the skins flat and cover the fleshy side in salt or sand, which will dry them out and delay decomposition. In a few days the hides will become hard and almost crispy, and they can then be transported to your tanning area. Once there, you’ll soak the hides: this cleans off dirt and gore and softens them up again. Scour the skins to remove any remaining flesh, then soak them in urine—this loosens the hair, which can then be scraped off. You’ll make the poop slurry we advertised earlier by mixing poo and water,* and then soak your skins in that: enzymes in the poop will cause the skins to ferment, softening them and making them more flexible. You can help this process by standing in your poop slurry and kneading the skins with your feet—just keep telling yourself you’re crushing grapes—but be sure to wash up with soap and water afterward, or better yet use nonhuman power (like a waterwheel) to knead the skins for you. After all this, two things will have happened: your animal skins will be soft, flexible, and ready for tanning, and nobody will want to get anywhere near you. To tan these skins, you’ll need to collect some appropriately named “tannins,” which come from trees containing the equally appropriately named “tannic acid.” The bark from oak, chestnut, hemlock, and mangrove trees is high in tannin, as is the wood of cedar trees, redwood trees, and more. Tannins are brown, so if you’re using wood instead of bark, look for r...