Wooden River Boat Propellers Can A Wooden Boat [galleon, Caravel] Go Up A River?

Can a wooden Boat [galleon, caravel] go up a river? - wooden river boat propellers

Is a wooden boat of the 1500s and up a river? My history teacher said that Africa was explored by Europeans in the 1800s, to have as their wooden boats and wooden boats can not go because a river, the current yield.
That is why they invented the steam engine.
As the boats are going down-river to London, and Seville, and in other European ports to vessels, but not the same in Africa?

Thus, these vessels can up a river?

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http://etc.usf.edu/clipart/25200/25235/g ...
http://img.nytstore.com/IMAGES/NSAPCP2_L ...

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