Couple with low speed and the unknown of the night, sailing at that time is vert dangerous.
A Prehistoric Log Boat is the most simple, and worst, ship in the game.
A Prehistoric Log Boat travels at a uniform speed, a very slow one.
The only reason one should use this boat is to travel to another island with enough resources to create another kind of ship.
To create said boat, simply craft 2 Medium Wood into a Building.
Then place in water.