Using inflated animal skins as floating devices is rather old and widespread tech. Floats: A Study in Primitive Water-Transport: https://www.jstor.org/stable/

Using inflated animal skins as floating devices is rather old and widespread tech. Floats: A Study in Primitive Water-Transport: https://www.jstor.org/stable/2844455 https://www.jstor.org/stable/2844455 Animal Skin Floats : https://www.iro.umontreal.ca/~vaucher/History/Prehistoric_Craft/Float.html https://www.iro.umontreal.ca/~vaucher/History/Prehistoric_Cr... Roman military pontoons made from inflated animal skins: https://www.researchgate.net/publication/291033772_Roman_military_pontoons_sustained_on_inflated_animal_skins https://www.researchgate.net/publication/291033772_Roman_mil... Sheepskin rafts are known in China since the Han Dynasty (206 B.C.-220 A.D.) The Assyrians did use inflated animal skin for their rafts. https://www.researchgate.net/publication/323672056_The_Reflection_of_Mesopotamia_Water_Transportation_to_Figurative_Arts https://www.researchgate.net/publication/323672056_The_Refle... By the way, the tech may save your life: https://www.artofmanliness.com/articles/how-to-turn-your-pants-into-a-flotation-device/ https://www.artofmanliness.com/articles/how-to-turn-your-pan...