254 JOURNAL OF THE PLYMOUTH INSTITUTION. 
“The rich and powerful first secure a strong place for their 
- personal safety, and the keeping of their prisoners and their wealth. 
They commonly throw up a mound of earth, surrounded with a 
deep ditch, upon the inner edge of which they establish a stout 
palisade of squared timber, strongly bound together, equal for 
defence to a wall, and strengthened by turrets or towers. Upon the 
centre of the mound is placed the residence, only to be approached 
by a steep bridge across the ditch.” * 
This very clearly shows what the disposition of such a place as 
Plympton must have been before the Norman Conquest. On the 
summit of the mound was the residence of the chief and his family. 
Mons. de Caumont, the well-known French antiquary, who paid 
much attention to this class of fortress, sayst that sometimes they 
were constructed in wood, and sometimes in stone. The importance . 
of the place did not determine the material of which it was built. 
Castles belonging to powerful men, situated in localities where 
materials were difficult to procure, or to transport, had only walls 
of earth and wood, while others of much less consideration had 
masonry walls, where stone was abundant, and the skill to use it 
available. 
The mound, where artificial (for a natural eminence often deter- 
mined the position of a castle), was always of a regular shape, that 
of a truncated cone. 
The residence upon the mound was approached from below by a 
bridge of timber, which spanned the ditch, and reaching perhaps 
to the top, perhaps only half-way up, was supported by wooden 
props and struts, in the ditch and against the sides of the mound. 
The Bayeux tapestry clearly shows us what kind of a building 
the Norman found in England, and indeed also what kind of 
building his immediate ancestors had made use of in their own 
country. We have the representation on the tapestry of the fortress 
of the city of Rennes, and of the taking of Dinan by the army of 
William in 1065. These towns are represented as simply keeps, 
seated upon their mounds. At Dinan we have not only the siege, 
but the resulting capitulation. The besieged are depicted defending 
their ramparts; the warriors, at the head of the wooden bridge 
thrown across the ditch, prepare to fling their javelins at the 
attacking party on horseback, who are evidently supported by the 
* See translation by Clark, “ Arch. Jour.,” vol. xxiv. p. 101. 
t Op. cit. p. 73. 
