During 1920, a plague broke out between a shared jurisdiction of China and Russia. The Chinese Imperial Court brought in a young doctor named Lien-teh Wu that determined that the plague was not spread by fleas but through the air. He expanded upon the surgery masks he'd seen in the West,...

• Codex is closer to modern books. The pages were made from folded leaves or parchments (animal skins) and bound together on one side, one after another. The earliest surviving codex dates back to the 4th century and is the greek biblical manuscript known as Codex Sinaiticus....