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Appendix No. 4.
Sierra Leone.
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54
Inclosure 1 in No. 5.
Report on the Defences of the Port of Sierra Leone.
THE printed Confidential Memorandum on Sierra Leone, by Colonel J. H. Smith, R.E., dated War Office, 12th April, 1881,* issued by the Inspector-General of Fortifications, is taken as the basis of this Report.
EXISTING SEA DEFENCES.
2. Fort Falconbridge is a lunette-shaped masonry battery for seven smooth-bore guns on high traversing platforms and firing en barbette; three guns were on each side to flank the river and anchorage, the seventh gun at the salient brought a direct fire to the general front. The gorge is closed by a defensible wall. The parapets form the only protection from an enemy's fire, as there are no traverses, &c.
The battery appears to have been long dismantled: the pivots, racers, &c., are either unserviceable, or have disappeared.
3. The site occupied by the battery is at the salient of an open space about 150 yards square, which forms a public recreation ground. The site is almost level, but the ground rises slightly in the direction of the capital of the battery (which is perpendicular to the line of the river, and of the proposed sea defences) towards the rear.
The cliffs in front are about 30 feet high, and large falls of rock appear to have recently taken place.†
4. If a space of 20 yards be left in front there will be, available for new works, a length of about 120 yards along each of the two lines of cliff.
One or two of the houses on the beach, which abut on the west of this site, will probably interfere with the fire of the left flank of a new work; they are of slight construction, and would not cost much to remove.
The existing masonry battery is of no use, and must be removed when new works are constructed.
5. West Battery. This work contains emplacements for four guns; the left gun in an embrasure could bear on King Tom's Point, the other three guns were mounted on high traversing platforms (central pivot) for fire to the general front, the right gun being able to bear on the wharf and custom- house. There are no traverses, store or magazine.
6. The battery is on the top of a cliff, 40 feet to 45 feet high, which has given way on the right to such an extent as to leave only 12 feet of earth in front of the crest.
Immediately behind the battery is the inclosure-wall of the Colonial Hospital, an ordinary door through which forms the only communication to the work. As will be seen further on, it is proposed not to retain this work, as a battery for garrison guns, but to reserve it merely as a site for musketry.
7. King Tom's Point.--Traces only exist of an old battery near the salient. The site is about 8 feet above high-water mark, and the entire peninsula is nearly level, rising only very slightly towards the rear (S), and is thickly covered with vegetation. Space ample for any required work.
EXISTING LAND DEFENCES.
8. These consist only of the fort formed by the defensible wall which incloses the barracks at Tower Hill. Fort Thornton exists only in name, as it has been nearly entirely removed to make room for Government House.
The defensible wall of Tower Hill Fort has imperfect flank defence, and is only provided with groops of loopholes at intervals. The slopes of the hill are not completely seen from the wall.
9. Nothwithstanding these defects the work is well worth retaining, as it has a good command over, and view of, the two most probable lines of advance of an enemy who may have landed, viz., from Signal Hill or Wilberforce on the west, or from the direction of Foura Bay on the east, by the road on the low ground near the river. The fort also has a good view of the ground both to the north and south. In the latter direction it is overlooked by the high ground (1,000 or 1,100 feet) at the new rifle range at Kortright Hill and neighbourhood, but as it is proposed permanently to occupy these hills as a defence against a land attack, Tower Hill will remain as an useful central work, well situated, to prevent the success of an attempted surprise and rapid advance on the town, by either of the two lines before referred to.
10. Immediately outside the south-west angle of the fort is situated the powder magazine. This should be brought within the line of defence by defensible walls connected with those of the main work.
The Martello Tower referred to in the War Office Memorandum has been lowered, and the ground-floor converted into a tank, which gives a head to the water supply of the barracks.
There are no other works of defence in existence; it follows that with the exception of Tower Hill Fort and Barracks any scheme of defence will require to be entirely new.
PROPOSED SEA DEFENCES.
11. The peculiarities of the anchorage and settlement as regards attack by ships are (1) that any works of defence must of necessity occupy points (Aberdeen, Look-out, King Tom, Falconbridge, and Farran), which are practically in a straight line; and (2) that these works will be attacked in detail,
* No. 7.
†The heights given in this Report are approximate only.-G. P.
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