The firearm “Flying Fire Crow” created in the Ming Dynasty is made in this way: bind the thin bamboo strips with tissue paper and paste it into the shape of a crow, which is filled with powder and propelled by four rockets. The “crow” is very powerful upon explosion and can burn raging fire strong enough to burn the enemy’s camp on land or boats on water. It’s the world’s earliest parallel rocket with multiple powder flasks, which is similar in the operational principle of today’s large strap-on carrier rockets.