Bourne Archive: 12th century Ship
http://boar.org.uk/ghiwxs7C12Ship.htm Latest edit 12 Mar 2011.
Text, page and picture ©R.J.PENHEY 2007.
A Twelfth Century View of a Ship. (ca. 1150-60)
Note the rows of nails along the lands of the strakes of planking. They mark this ship as being clinker built, though the artist has not fully grasped the details. Note particularly, the rudder on the centre-line of the vessel. It had replaced the earlier steering oar, used until this time. This is among the earliest representations of such a rudder in a north-European ship so the ships in which Hereward travelled will have been of the earlier sort.
It is interesting to see that the animal head carving has been transferred from the head of the sternpost to the head of the rudder stock. Some such arrangement was necessary in order simply to permit the use of a tiller. The artist was sufficiently at ease with the new technology to have noticed that.
According to the several views of ships in the Bayeux Tapestry, steering with an oar on the starboard quarter of the ship was clearly still current practice in the 1060s (Grape). In the picture below, of the earlier ship, the man in the forward end is taking soundings with a pole, as the vessel approaches a beach.