Venetian-style galley, ca. 1571. A mechanism under the deck permits both banks of oars to row in tandem when a key is inserted into the stern and rotated.

(Sorry for the low-quality pictures, I'll get some better ones up soon.)

I drew on the following resources for this model:

Akira Sasano's model of a Venetian galley:
http://www001.upp.so-net.ne.jp/a-sasano/english/e-galley.htm