NEW ZEALAND DEFENCES: HIGH-ANGLE FIRE (MEMORANDUM RESPECTING, BY MAJOR-GENERAL STEWARD).

Appendix to the Journals of the House of Representatives, 1889 Session I, H-35

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1889. NEW ZEALAND.

NEW ZEALAND DEFENCES: HIGH-ANGLE FIRE (MEMORANDUM RESPECTING, BY MAJOR-GENERAL STEWARD).

Presented to both Houses of the General Assembly by Command of His Excellency.

This class of fire is obtaining much attention at present. Against vessels with protective decks it is clearly the only fire likely to be effective at long ranges. Even in the case of ordinary cruisers, unprovided with horizontal steel plating, a plunging fire is feared ; for if plugged Palliser shells are fired, one may pass through the decks and out at the bottom. By means of horizontal fire with high-velocity guns ranges of 4,000 to 5,000 yards can be commanded from shore when ships have to be dealt with ; but the vessels intending to shell a town or port would carry on operations beyond this range —say at 6,000 to 7,000 yards—and it is absolutely necessary that there should be some gun-fire on shore capable of reaching vessels thus occupied, and preventing their taking up suitable positions for shelling—in other words, capable of keeping these vessels on the move, for while on the move neither the range can be accurately ascertained by bearing nor can accurate fire be delivered—at least, from the deck-guns of an ordinary cruiser operating at very long ranges. At Wellington the town, though hidden from view, is open to long-range fire from vessels in deep water lying near Lyell and Island Bays, south-west of the town. The neck of land 250 ft. high which intervenes presents no obstacles to fire, for the fire can be directed by compass. . Besides, it does not appear impossible that what has happened at Sydney—viz., the creeping of the town over the high ground and towards the shore—may happen at Wellington. Such an extension is not the provision of an important butt, such as the business quarter of the town would be in the eyes of the enemy, and its destruction would not produce the same effect as a conflagration set up in the business quarter and on the quay-sides by the enemy's shells ;:;: but it would be one of the items in the bill of damages which an enemy would endeavour to make as extensive and heavy as possible, with a view of squeezing the town authorities. At Dunedin the town itself is also liable to a similar mode of attack; and from waters close to the defended port of Lyttelton the Town of Christchurch can be reached at long range, and no magnetic bearings would be required for its attack, as the incidence of the shells could be observed from the main-tops. Two high-angle-fire guns, on mountings admitting of 35° elevation, would amply suffice for each place; even one should bo provided if funds for the supply of two be not at first forthcoming. These guns would be supplementary to the present defences, and would fill a gap at present unoccupied. The number of guns of this class proposed might appear to some to be inadequate. The condition of their employment, however, is that they shall be well-manned, wellfound, and provided with a perfect system of range-finding. Thus equipped, the two would do all that is wanted, and afford better results than a much larger number of guns less carefully managed. An ill-directed fire of a plunging character, when delivered at Very long ranges, creates no alarm, and would entirely fail in its object. Becent trials in the Isle of Wight with a relined and polygrooved 9in. 12-ton gun gave excellent results. With 2501b. studless projectile (2581b. with gas-check) and 501b. charge of P. powder, practice at 9,500 yards range was carried on at a drifting target (speed about 4 knots), angle of 12|-° elevation. The target was hit three times, and all the shots fell close. Banges and direction were given from an elevated observatory 300 yards distant from gun. The mounting, to my mind, was not calculated to improve the shooting, as the sharp downward recoil and rebound inseparable from the class of mounting used (sloping platform) has a prejudicial effect on the accuracy of the fire. With such fire from a shore the bombardment of a town from cruisers would be impossible. To provide guns suitable for this class of fire, also mountings, at little cost, is the problem to be dealt with. The Imperial Government contemplates utilising their 9in., 10in., and llin. M.L. guns for this purpose, so it would be of no use begging for any of these. They are wanted to be of a good size and throwing heavy projectiles, as the vessels they may have to cope with" may carry deck-plating varying betwjsen l£in. and 4in. in thickness. In colonial waters such hostile vessels will be scarce, and the adapted commercial vessel is more likely to be the class of vessel that an enemy would employ; and therefore a colony may safely provide lighter ordnance for high-angle fire than the Mother-country would venture to do. The Bin. gun, if provided with modern rifling, so as to take studless projectiles, with gas-checks, may be considered sufficient for the purpose.

* Picric-acid-filled shells do fivo times as much damage as a powder-filled shell can.

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To obtain this class of gun it is necessary to procure 7in. -7-ton M.L. guns, and bore them to Bin. calibre, introducing polygroove rifling in place of the old broad grooves, which are suited only for studded shot, and which produce such highly inaccurate fire. "With the old single-plate mountings strengthened and adapted for high-angle fire, and properly installed, these Sin. polygrooved guns will be all that can be desired for the purpose under consideration. It happens that several old 7-ton 7in. M.L. guns and mountings, and old equipments, are beingreturned to store (Woolwich), and could, I think, be obtained at the cost of old iron, it is even possible that the Secretary of State for War might make a present of some of them were he moved to do so. The cost would be approximately as follows : — 7in. 7-ton gun fIVI.L.) ..'. ... ... ... ... ... 70 Carriage and platform, single-plate ... ... ... ... 50 Boring and rifling of gun ... ... ... ... ... ... 50 Transport of gun... ... ... ... ... ... ... 10 Proof of mounting ... ... ... ... ... ... 20 Alteration of carriage anil platform to afford high-angle tire ... ... 700 Projectiles ... ... ... ... ... ... ... 300 Accessories at reduced price ... ... ... ... ... 50 Installation in colony ... • ... ... ... ... ... 600 1,850 The question of the provision of high-angle lire for the three ports named above will have to be faced some day, and there is now an opportunity of getting the guns at a moderate cost. The course I would recommend is—(1) That the gift of the guns should be applied for, and, if not the gift, their purchase at a low figure should be arranged, the Imperial Government storing them and their mountings until the colony requires them ; (2) that one gun and platform, with carriage, shall be altered in the first instance, and be sent out to the colony with a complete equipment, and there tried—the remaining five guns and mountings to be taken in hand when funds are available, and dealt with singly or all together according to circumstances. E. Habding Steward, 20th October, 1888. M.-General. {Approximate Coal of Paper. —Preparation, nil; printing (1,200 copies), 19a. 6d. i.

By Authority: Gkoboe Didsbury, Government Printer, Wellington.—lBB9