C463 Wind as a Thrust

"Great Chieftain, you mean we can use the wind to row?" The craftsmen were very interested in Wu Ya's suggestion.

"Yes, you guys can look at this..." Wu Ya drew a point on the ground to indicate the boat. Then he drew two lines to indicate the river bank and the boat was in the river. Then, he mentioned something about the balance of the three forces.

The principle was very simple