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but of different qualities, is seen in the third class cruiser Topaze and the scout Sentinel. The following table shows the main features of these vessels :

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In the latter case it is seen that the ship has only a slight armament of 12-pounder and smaller guns, with only 150 tons of coal at the designed draught. The machinery is 17,000 I.H.P. for the 25 knots desired. Thus the ship is only able to carry herself and her machinery with a comparatively small load, in order to reach the high speed of 25 knots. In the former case the ship is able to carry an armament of 4-in. guns, with a large amount of coal, but this increase of load carried can only be obtained by having the lower speed of 21 knots. It is seen that an increase of speed from 213 to 25 knots, or an increase of 15 per cent., means an increase of nearly 75 per cent. on the power.

CHAPTER XXIV.

NOTES1 ON THE LOSS OF H.M.S. “VICTORIA” (June 22, 1893).

CIRCUMSTANCES leading up to the collision:

The fleet was proceeding in two lines, the Victoria leading the starboard column, the Camperdown leading the port column. The ships were proceeding at a speed of 8.8 knots, the two lines being 1200 yards apart. At the time of the signal to turn, the helm of Victoria went "hard-a-starboard" 35° (corresponding to a tactical diameter of 600 yards). The helm of Camperdown was put at 28° (corresponding to a tactical diameter of 800 yards). When the ships had turned through eight points, it was recognized that collision was inevitable, and the port engines of Victoria and the starboard engines of Camperdown were reversed, but this had little effect, as the collision took place one minute later. The speed of the ships at the time of the collision was from 5 to 6 knots.

The Camperdown struck the Victoria nearly at right angles, about 65 ft. abaft the stem. The blow was just before important transverse bulkheads (Fig. 208). Both the ships turning rapidly at the time of the collision caused the sterns to swing together, and this considerably widened the breach in the side of the Victoria. This, together with the hole caused by the original blow, destroyed the connections of the bulkheads above-mentioned with the side of the ship. The value of these bulkheads was thus completely destroyed, and the compartments on either side were thrown open to the sea.

For the first minute after the collision the two vessels were locked, and during this time the Victoria heeled slightly to starboard and settled a little by the bow. After the Camperdown had cleared, the Victoria continued to settle by the bow and to increase her heel to starboard. These movements proceeded gradually for

See also end of Chapter VI. regarding the question of watertight doors.

about ten minutes, when a sudden lurch to starboard took place. The ship turned bottom up and finally sank by the head.

It will be desirable to briefly describe the main features of the Victoria in so far as they bear on this question. The ship was built to carry two 111-ton guns in a turret forward, and

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the great weight of this armament and the armour necessitated a somewhat low freeboard forward, viz. about 11 ft. Abaft the turret was a battery with fronts inclined abaft the beam, as shown, to give a large arc of training to the heavy guns. These fronts had armour doors in them, and the sides of the battery

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had ports for the 6-in. guns. With these doors and ports closed, the freeboard near midships was about 18 ft., with them open the freeboard was about 12 ft.

At the time of the collision a number of watertight doors forward were open, the turret ports and scuttle on upper deck

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were open, and the doors in the front of the battery and the gunports in battery side were also open.

For convenience it will be desirable to consider separately the two movements which actually proceeded simultaneously (Fig. 209), viz.

1. Depression of the bow.

2. Heel to the wounded (starboard) side.

1. Depression of the bow.-About four minutes after the collision the bow had sunk enough to bring the stem-head under water The forward part of the deck then became submerged, allowing water to pass down the scuttle on the upper deck and then down the turret ports, the water level reaching to the sill of the door in the battery front starboard, and the bottom of the foremost. gun-port. At this moment the stem-head was depressed about 23 ft. from its normal position.

2. Heel to starboard.—Accompanying this depression by the bow, a gradual heel to starboard took place, until a heel of about 20° was reached. At this time the door in the battery front and the foremost 6-in. gun-port were just awash.

Both the above movements were accelerated by the motion ahead of the Victoria, the ship being made to steam slowly towards the land with the helm hard-a-starboard.

At this time, at the heel of 20°, a sudden lurch to starboard took place, and the vessel capsized and went down head first.

Calculations have been made, using for data the observed conditions, to investigate the cause of the sudden lurch that was observed; the suddenness of this lurch was without doubt the cause of the great loss of life.

The loss of buoyancy caused by the opening up of the compartments forward, which were inevitably flooded by the collision, and those flooded subsequently through open doors and hatchways, caused a change of trim of 29 ft., or 23 ft. depression forward and 6 ft. lift of the stern. Taking the ship in this condition, but supposing the turret ports, battery doors, and gun-ports closed, the vessel would have a positive metacentric height of ft. In Fig. 208 the shape of the intact waterplane is shown by I, and the shape of the waterplane area under the above condition is shown. by II. In Chapter XVI. it is seen that the distance between the centre of buoyancy and the transverse metacentre is directly proportional to the transverse moment of inertia of the waterplane at Under the conditions

which the ship is floating (BM = √).

assumed above, the waterplane area would have a transverse moment of inertia of 3,888,000, giving such a position of the transverse metacentre that a metacentric height of 8 ft. was retained. The ship under this assumed condition was in a condition of stable equilibrium.

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