260 JOURNAL OF THE PLYMOUTH INSTITUTION. 
passable at low water, and these weak portions of the natural 
fosse required almost as much protection as the open ground of 
Mutley. Then there were detached works at Stonehouse and 
Lipson Mill, intended to guard against flank attacks; and a very 
important redoubt across the Cattewater, known as Mount Stam- 
ford. Its special object was to secure the free use of the harbour, 
and it commanded the entrance of Sutton Pool. These walls, and 
breastworks, and redoubts seem very poor affairs in days of Break- 
water Forts and Woolwich Infants; but we must judge them by 
the times in which they were erected; and the best proof that 
they suited these is that with a few additions they preserved the - 
town during a nearly four years’ Siege. When operations com- 
menced, the outworks were very defective; and so far from being 
connected that the enemy could in many places approach within the 
line without molestation. There are indications that the existing 
hedges were utilised as far as possible, and New Work was apparently 
added to the line as first drawn, to command Mill Bridge. 
The maps which accompany this paper, to a certain extent 
conjectural, are based upon the best authorities extant, and can be 
erroneous only in small matters of detail. In the main, they may 
with confidence be accepted. The map of the town is founded on 
the oldest trustworthy plans in existence, which reach up to within 
eighty years of the Siege period, checked and corrected, so far as 
the streets are concerned, by the records of building operations 
which have been handed down, and by the positions of the older 
houses yet remaining. The general outline of the walls is taken 
from a sketch map of Plymouth and its defences, which formed an 
appendage to the chief Siege tract, published in 1644, and which 
has been several times reproduced. It will be found in close fac- 
simile in my ‘‘ History of Plymouth.’’ It makes, however, no 
pretensions to strict accuracy, nor was it drawn to scale; and 
whilst accepted as indicating the general character of the circum- 
vallation, has been interpreted by the aid of such portions of the 
wall as yet remain, or the position of which is distinctly known. 
The other map presents as accurate a view as is now practicable 
of the whole system of defence in its most complete and extended 
state, which would be somewhere about the latter part of 1645. 
To this there is one exception. Mount Stamford then, as a work 
of defence, had ceased to exist, and Mount Batten had become a 
more important fortification than represented. As we have no 
