924 KEPORT— 1888. 



which, on exposure to air and water, by degrees assumes its original character, only 

 showing more plainly the danger to which the structure has been subjected by this 

 continued exposure. 



The result of the great recession of the shore north of the Castle before described 

 and delineated on the accompanying plan is that the sea eddies round the buildingk 

 ■which at high water forms a kind of point or headland, and the sand is scoured out 

 from under or before the Castle walls: this great decrease in the height of the fore- 

 shore has not only induced tlie permanent loss of beach from its not re-accumulating 

 at a level so much below high water, but the sea also much sooner reaches the 

 Castle walls, renderingthedifficulty of construction of any permanent work of defence 

 greater j-ear by year. Another result of the lowering of the shore and loss of the 

 shingle barrier is that the Castle walls are much sooner reached by the tide, longer 

 subject to its influence, and that the footings are gradually more and more under- 

 mined, and the sand crust on which they rest exposed in the same degree, and that 

 the body of sand below is more saturated, and a larger amount is withdrawn by the 

 tidal recession. That the sand is highly charged with water under the Castle is shown 

 by the manner in which it pours from under it over the foreshore at low water, and 

 the manner in which it boiled up from under the footings in the trial holes that were 

 sunk for their examination, when none was to be seen coming in from the opposite 

 side. The result of this constant saturation beneath the foundations and withdrawal 

 of water therefrom in such a material as that on which they are founded is evidenced 

 by the numerous fissures in the outer main walls of the building, in the piers therein 

 and in the basement gallery walls ; still former fissures existed of considerable stand- 

 ing of which many of the modern ones are merely an extension. Similar indications 

 of settlement may also be traced in the upper embrasures, though these latter may 

 be attributable in a degree to the age of the building and causes producing vibration. 



The settlement of the main building is shown by a fissure around the small 

 window in the keep staircase turret; those in the basement walls may be traced all 

 round, and appear worse next the sea. Some are older than others, and have been 

 pointed up some time back. The more recent settlement is shown in places by the 

 breaking of the Caen ashlar stones where the bearing is unequal. The vertical settle- 

 ment is also shown by the bridge from the ramparts to tlie door into the principal 

 room of the keep having altered its form; many of these indications are, however, of 

 considerable standing : this may be remarked of the basement, especially on the land 

 side. 



There are fissures in the footings of the soutli revetment or counterscarp wall in- 

 dicative of settlement and an outward movement similar to that causing the failure 

 of the north wall. 



The natural result of the withdrawal of so large a quantity of the sea barrier 

 immediately from the base of the north moat revetment or counterscarp wall has been 

 for the last six montlis to gradually undermine it from the seaward and to carry the 

 sand away by degrees from under it by the underdraught of water from the moat on 

 the recession of the sea. The wall, which had cracked in various places, fell over in 

 tJiree detached masses, leaving two large breaches for the sea to enter by on tlie 

 11th ultimo, just as the brick wall of Battery No. 1 had previously fallen from similar 

 causes. 



If the Castle is to be maintained something must be done immediately. 



In the first place, I recommend the removal of every remaining timber of the 

 north groyne, north intermediate, and centre groynes, and of the north timber reyet- 

 ment from its present site. 



The south intermediate groyne, south groyne, and south timber revetment to be 

 retained for the present, as their removal would entirely alter the condition of the 

 shore southward. 



In reference to the above remarks and those that follow, I beg to refer to the 

 plan accompanying my report of 1856, also to the enlarged plan of the Castle and 

 adjoining frontage, showing the proposed works accompanying this report. 



I next recommend the immediate construction of a sea barrier across the moat 

 from the outer or N.E. curve of the N.E. tower to the angle in the moat, retaining 

 wall formed by the intersection of the two circular curves therein, such barrier having 

 a N.W. and S.E. direction, and including within it the moat tank or drainage cesspool. 

 It might be formed of the 'blocks of stone from the fallen north revetment wall, 

 backed with masses of concrete therefrom, and the wliole backed up with material 

 procured from the neighbourhood, the pitching of the crest and back slope laid on 

 clay puddle. 



