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Armstrong's protected barbette mechanical loading system for South Australia.

In 1997 I had the pleasure of reconstructing the carriage and platform for one of the two existing 10 inch 20 ton RML (Rifled Muzzleloading) Armstrong guns at Fort Glanville, South Australia (SA). (1) In 2001 the mechanical loading system was reconstructed and rendered operational. (excepting the hydraulic washing out apparatus). At the time of writing 2002, the elevating mechanism is being reconstructed. Before describing some of the points of interest with the reconstruction of the mechanical loading system itself, the following is a brief history and description of the system as was designed for South Australia in 1878.

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Historical context

War scares: South Australia's immediate reason for purchasing modern coastal guns in February 1878 was the fear of attack by Russian cruisers during the Russo-Turkish War of 1877-78. This fear arose because Britain was at that time by diplomacy, attempting to prevent Russian expansion towards India. This situation prevailed for many months, during which time the Australian colonies sought up to date advice on their defences.

Defence advisers: The British Colonial Office was requested in December 1876 to seek the services of the renowned Col Sir W F D Jervois RE (Royal Engineers). His services were secured, and after some months delay he reported upon the defences of Queensland, New South Wales, Victoria, South Australia in Oct 1877 and finally Tasmania. The man who initially assisted Jervois and who subsequently the nuts and bolts of many Australian forts and batteries was Lt Col Peter Scratchley RE. Another RE officer of great assistance to South Australia was Lt Col E Harding Steward, whose role in England was to advise upon all matters of land defence.

South Australian Defence Scheme: Jervois' defence scheme for South Australia recognised that the only probable form of attack would be by an unexpected arrival of a small squadron or a single cruiser, with the object of capturing merchant ships in coastal waters, seizing coal, or threatening to bombard South Australian ports for contribution and the destruction of commerce. (2) The landing of enemy troops was seriously expected by the populace and although never a realistic scenario, gave cause to many decades of volunteer rifle and field artillery preparations, before fading away until the next war scare. The main target in South Australia was Port Adelaide, six miles from the inland capital of Adelaide. Because of Adelaide's long straight coastline, the primary choice of Jervois for coastal defence was a seagoing armoured cruiser of greater power than the perceived threat. In addition he proposed two batteries (since known as Forts Glanville and Largs), to essentially defend Port Adelaide, which town was within easy reach of the guns of cruisers in the offing. Within weeks South Australia's Agent General in London was made aware of various designs for ships in contemplation, including Armstrong gunboats for China, and although the matter was pursued with some vigour, it was dropped because of both the waning of the scare and the reluctance of the South Australia government to afford the expense of such a purchase, especially as an addition to forts, at that time. (3)

Indent for ordnance

In Feb 1878 the South Australian government telegraphed the Agent General to expedite an order on the War Office for ordnance, among which were two 10 inch 18 ton RML guns, carriages, platforms and "C" pivot racers. (4) At this time South Australia's newly commissioned Governor (Jervois) was enroute to England for private reasons. In late May 1878 he visited Stewart Rendel at the London office of Sir W G Armstrong & Co. (5) Jervois was shown a model of a system of loading guns in an open barbette battery, but under cover of the parapet (to avoid the annoyance of shrapnel!) He was impressed and immediately telegraphed the Chief Secretary in South Australia, strongly recommending that the new Armstrong system should be purchased, and that instead of the Woolwich "service" gun, a new more powerful (3.5 calibres longer) piece of the same 10 inch calibre should be adopted. The South Australian Commandant (Lt Col M F Downes RA), the South Australia Government and the British War Office made no objections to this new untried system; it appears Jervois' professional opinion thwarted all doubts. Jervois subsequently obtained the services of Col Steward RE to oversee the technical details of the order, and arrived back in South Australia in August 1878 to take up his governorship.

Stewart Rendel, the salesman, contacted his brother George W Rendel, Civil Engineer at Elswick, Newcastle upon Tyne, and apprised him of the impending contract for South Australia. George was apparently quick to take advantage of South Australia's urgent need for ordnance, for on the 7 June 1878 he filed for Patent (No. 2282). The order for the contract was given on 3 July and completion given as four months from that date.

In mid-November 1878 Steward advised Jervois of his dealing with Armstrongs. (6) Steward had requested that the parapet be raised by 6 inches to 7 feet so as to give more overhead cover to the men at the gun. Although Rendel's provisional patent only provided for protection against direct fire, Steward requested that the gunners at the loading apparatus be further protected by overhead (bombproof) cover, viz: wrought iron plates and concrete. (7) To effect this the floor of the loading gallery was lowered 3 feet. He also requested a change in the design of the loading system, from a trolley with rack and pinion driven rammer, the provisional patent (Sheet 1 on p.26), to a trough moved by a counterpoise lever (or 'seesaw') and adopted for filling by hand, the approved patent dated 15 November 1878 (Sheet 2 on p.26). As to who actually conceived of these changes I am unable to discern, but if it was not Steward, then Rendel (who was pro-hydraulics) may have had other designs at hand for contemplation during the early stages of the contract. Rendel was quite an inventive man, and it is noted that although the Patent mentions a chain driven rammer (not meaning a chain-rammer), wire rope was used instead as the driving medium. It is presumed that much of this detail was worked out on the shop floor as testing or experimentation progressed by Elswick Ordnance Company (EOC) employees, and all at colonial rather than Imperial risk and expense.

Another later version of the mechanical loading system (sheet 3 of Patent No. 2282, on p.28) was adopted at Fort Lytton (QLD), Outer Middle Head (NSW), Bluff Battery (TAS), Batteries Naam and El Baroud, Tangier (Morocco) and Puckpool Battery (UK). The author is unaware of any other existing emplacements.

Steward visited EOC on two occasions. Upon the second occasion one of the guns had been mounted in the open at the factory behind a dummy parapet and loading gallery. This event appears in the miraculously surviving photograph on the opposite page. Steward reported that the system worked remarkably well. After sorting out the details of the hydraulic jet washing-out apparatus and satisfying himself with final details, one of the guns was sent to Shoeburyness for range and accuracy trials, ie, graduation of the sights in degrees.

The two protected barbette systems were shipped to South Australia at the end of June 1879 and arrived at Port Adelaide in late September. The 20 ton guns were offloaded by crane onto flat top railway carriages and taken by special railway spur line to a point outside of the fort, then winched up a wooden ramp and mounted by the contractor John Robb. The loading systems and both guns were first tried on 2 October 1880.

Description of the Mechanical Loading System

The following is an extract, but has been modified by the author to refer to Fort Glanville in the present tense so as to project the Armstrong sales-pitch of 1882.

Memorandum by Sir W G Armstrong & Co "Protected Barbette" system of mounting and working coast guns. (8)
 Before entering upon a description of the arrangement and advantages
 of the "protected barbette" system, it may be well to state that
 though this system is applicable to either muzzle or breech-loading
 guns, its advantages are more fully developed in the use of the
 former, and the preference is given to them, for the following
 reasons:


1. It is now conceded that there are no inherent advantages in breech-loading guns which cannot be obtained with muzzle-loaders; but that if two guns have the same proportions of bore and rifling, and fire the same charges, the same ballistic results can be obtained whether the gun be loaded at the muzzle or at the breech. The choice between the two systems depends therefore upon the relative convenience in working, and adaptability to situation and circumstances.

2. The advantages of simplicity of construction, absence of small details, and non-liability to derangement by exposure or rough usage, are greatly in favour of the muzzleloader.

3. On board a ship, where constant supervision is available, and cleaning of the guns forms part of the daily routine, and where on account of the limited space, muzzleloading with guns of the present length presents serious difficulties and great exposure of the men, breech-loading guns are employed with great advantage.

4. In a coast battery, where the guns are left exposed to the weather, often for long periods without any supervision or attention, it becomes imperative to adopt the simplest possible construction, to avoid all loose pieces and details which require to be kept in a store; and in fact, to have a gun that will remain for years in good condition simply by excluding the air from the bore, and be serviceable after a few minutes' cleaning whenever required.

5. Choosing then the muzzleloader for coast service the objects kept in view in designing the "protected barbette" system have been the following:

(a) To obtain for the men working the gun the greatest possible protection.

(b) To reduce the number of men required to a minimum.

(c) To provide the most effective and economical arrangement of emplacement.

The "protected barbette" earthwork has been designed to fulfil, as far as possible, all the conditions laid down above.

Description of the apparatus: The interior of the emplacement is rectangular, lined on three sides with brick walling to support the earthwork. The front wall has a height at its lowest point of 7 feet (2.1 metres), while the height gradually rises in the return walls of the traverses (merlons) on both sides. In the traverse between the guns is a bombproof arched gallery in which the mechanical loading apparatus is fixed, and in which the men loading the gun are protected. The 400 lb (182 kg) projectiles are brought up to the loading trough (or cradle) by a special lever trolley, while the cartridge cases are brought up by a bearer, both charges reaching the trough by a pathway around the outside of the traverse. (9) The front end of the gun platform rests upon a strong pivot (B pivot) fixed close to the front wall of the emplacement, and at about the middle of its breadth. The gun is loaded when run out, in which position the centre of gravity of the gun and carriage is almost directly over the pivot, so that the whole mass is in the most advantageous position for being traversed, which is done with traversing gears, and is so arranged as to give a rapid movement when changing the gun from one position to another, or a slower motion when laying the gun. (10) For loading, the gun is traversed until its axis is parallel with the face of the parapet, and the muzzle pointed towards the loading gallery. The men performing these tasks are below the parapet and sheltered by the mass of the gun and mounting. The muzzle is then depressed about 13 degrees until it rests upon a wooden muzzle rest, in which position the axis of the gun is in a line coincident with a wooden rammer. The rammer (approx 8 metres long) slides in a long wooden sheath (hollow beam) fixed in the gallery, its lower end is embedded in the parapet wall. A flexible wire rope passes several times around a 30" (760 mm) diameter dram and thence over a two-grooved guide pulley (both attached to a pair passes several times around a 30" (760 mm) diameter dram and thence over a two-grooved guide pulley (both attached to a pair of wooden posts firmly attached to the floor and ceiling) The ends of the wire rope then pass over metal rollers, front and rear, on the underside of the sheath and are securely attached to the ends of the rammer. By turning the drum in one direction the rammer is drawn forward out of the sheath, and by turning the drum in the reverse direction the rammer is withdrawn. Also pivoted to and straddling the aforementioned posts is a counterpoise lever or "seesaw". Pivoted between the front end of the seesaw is a cradle which receives the cartridge and projectile. Iron counterweights are bolted to the other end to assist in balancing the seesaw (when charged) on its pivot. Attached below the rear end of the cradle is an iron counterweight to ensure the cradle resists turning about its pivot during raising and lowering of the charge. The seesaw is raised by a chain-winch connected by a chain over a pulley to a bar below the ceiling, and to which bar two chains extend over two pulleys down to the counterweights of the seesaw. Before the apparatus can be operated a double sliding door is opened, and handles are attached to the rammer and seesaw drive gear shafts.

Loading operation: The front end of the seesaw (nearest the muzzle of the gun) is lowered to the ground and kept there by a pawl (catch) on the chain winch. The lid of the cradle is then raised, and a cartridge, stored inside a zinc cylinder (cartridge case) is brought up from the cartridge lift by two men on a wooden bearer and slugged out of its case into the cradle nearest the gun. The battering (full) charge is 46" (1170 mm) long, and contains 130 lbs (59 kg) of [p.sup.2] gunpowder; the service (reduced) charge is 35" (890 mm) long and contains 100 lbs (45.5 kg) of [P.sup.2]. The lid is then closed. A 400 lb. projectile is then collected from the top of the shell lift, automatic gas-check (dual purpose driving band) attached, fuzed if a shell (common or shrapnel), hooked up to a special lever trolley by selvagee (sling), run around the outside cast iron tramway to the cradle, fuze set, and projectile laid in the cradle by tilting the long lever handle of the trolley. It is necessary during this action to align the lugs on the gas-check with the rifling guide grooves in the cradle so as to ensure the projectile in ramming is in alignment with the rifling of the gun. The sling is then removed, projectile chocked (so as to prevent it sliding to the rear during raising), and if common shell or shrapnel, the fuze safety pin/s withdrawn. The catch is then released and the seesaw, supplemented by the action of one man at each end of the seesaw, raises the front end of the cradle up the muzzle rest & guide post to the muzzle of the gun. Just before the cradle reaches its uppermost point the hooks at the front of the cradle come into contact with similar hooks on the post. This action, as the seesaw continues to rise, causes the cradle to rotate about its axis, and as the cradle moves to a position where the longitudinal axis of the cradle is in alignment with the axes of the gun and rammer, the cradle also in effect moves away (60 mm) from the muzzle of the gun. (This allowed the excess water from the hydraulic jet washing-out apparatus to escape without running through the cradle.) The motion of the seesaw is arrested by its lower end coming to rest upon the gallery floor. The drum carrying the wire rope is now revolved and the rammer is drawn forward, pushing the charge before it into the gun. A continuous motion is maintained so as to cause the motion to be arrested by the lugs on the gas-check being forced into the ends of the rifling grooves where they die out just before reaching the 12" (305 mm) diameter chamber of the gun. This prevents the projectile from moving once the rammer is withdrawn. (11) As soon as the charge is home the rammer is rapidly withdrawn, the cradle lowered to receive another charge, while the gun is elevated till it clears the edge of the parapet, traversed round into any required position (135 degrees maximum traverse) and laid in the ordinary way, ie, with open metallic sights. As soon as the gun is fired it is trained round to the muzzle rest, depressed to lay upon it, and a jet of water sprayed up the bore from the hydraulic jet apparatus. (This was a vertical cylinder filled with water, above which was a moveable heavy weight (accumulator) mounted upon a brass piston. Upon opening the stop-cock the weight forced the water out of the cylinder via a hose and nozzle up to the breech face and chamber of the gun.) This dispenses with the need for the normal damp sponge to douse any live embers. (12) The gun is then reloaded. (The rate of fire was roughly one round every three minutes).

In the event of any damage to or derangement of the apparatus, which from its protected situation and simple construction is not likely to occur, the cartridge and projectile may be lifted to the muzzle of the gun when depressed into the loading position by a davit freed to the front of the platform, and passed home into the gun by an ordinary hand rammer in the usual way, the men performing this operation being almost as perfectly protected (standing upon a banquette in front of the mounting, and on both sides when using "bell" ropes to pull the rammer) as they are while working the mechanical loading system.

Performance in South Australia

On 8 April 1880 the Director of Artillery in England sought a report from the South Australian commandant as to whether the system was satisfactory. This request was not responded to until the system had been first tried in South Australia on 2 and 16 October 1880 when several rounds were fired at 3,500 and 2,500 yards (3200 & 2286 metres). (13) Col Downes replied that the system had worked satisfactorily and made the following observations (in brief):

1. That there was a tendency for the gas check to override and tear the silk bag of the cartridge. He solved this by loading the cartridge separately. (14)

2. From oblique fire there is not nearly the same amount of protection, especially if shrapnel is used.

3. In order that the loading and working of the gun should be satisfactory, the pivot and drum upon which the gun revolves as also the loading trough through which the rammer works, must be placed with mathematical accuracy. Any incorrectness in first mounting, subsidence of the foundations, construction of the masonry, &c would be fatal to the working of the guns until some correction were applied. (Apparently one of the pivots had already slightly subsided with corrective action being necessary). Again, as regards the loading trough, this must be placed so that the rammer working therein is in exact prolongation of the axis of gun when depressed to the loading position.

Downes found that at one stage the rammer was out of alignment, but was able to remedy it. He pointed out the absolute necessity of the most perfect alignment of all parts so as to avoid a failure of the system during action. Downes included in his report a description of the mechanical loading drill

Some of the points which are worth highlighting from the drill are as follows:

1. Most of the Armstrong Protected Barbette batteries comprised two guns, a left-handed and a right-handed mounting. This was because both guns pointed into a central loading gallery located between them, which for the greater protection of the two detachments had the elevating and compressor gear mounted on the rear side of the mountings when they were in their loading positions.

2. Each gun detachment consisted of 14 gunners (26 when both guns were operated together), 5 of whom were underground in the shell and cartridge stores and two more constantly in the loading gallery.

3/. Most of the gunners had several functions and positions to attend to, rather than being at fixed stations. (Not to be confused with changing Numbers)

4/. Since the axis of the gun was more than 8 feet above the gun floor the radial firing vent was located at 45 degrees to the vertical, ie, in a position where it was more easily served than if on top of the gun. (15)

In December 1881 Col Downes made another report upon the system. (16) This was in response to enquiries by officers of the Royal Artillery in England. He reported little change to his previous report other than that when both charge and projectile were rammed together the greater strain on the wire rope tended to cause it to get onto the cogs of the wheel and damage the rope. (17) No further changes of any consequence were made to the loading system after this date. Artillery practice continued with the guns until March 1893 when the mechanical loading system was taken out of service. (18)

Adoption by Her Majesty's service: The Armstrong Protected Barbette system occurred during a time of crisis. The British War Office saw merit in the novel system, but as they were committed to reliable service systems, they chose to wait and see how the Armstrong system fared. They did however in November 1880 conduct some undercover loading experiments with a 12.5" 38 ton gun mounted en-barbette at Cliff End Battery, Isle of Wight with some success. (19) Later, and it might be supposed after they had time to paw over Col. Downes's reports, another experiment was tried at Shoeburyness with a 10.4" 25 ton RML, (20) but using the Armstrong system. The Ordnance Select Committee reaffirmed the advantages of the system, but in light of developments in ordnance and gunnery, they noted that the gun and part of the carriage were exposed during traverse from firing to loading positions during the time of loading, and during traverse back to the firing position, an interval of nearly three minutes. The time occupied by these operations would, they said, render the following of a passing enemy difficult and uncertain,. The nature of the emplacement was not suitable for an arc of fire of more than 140 degrees. The mounting , which was practically front pivot, necessitated a large and open emplacement of 35 feet (10.6 m) frontage, which was much exposed to projectiles having a falling trajectory. (21) They then proposed a central pivot carriage with a smaller emplacement, . but an Armstrong of this form was already operational at the Bluff Battery, Bellerive, Hobart, Tasmania. Other authorities were unhappy with the fact that every time the gun was loaded you had in effect a loaded gun pointing into the magazine. Again, this was not new.

The War Office had something even larger underway; Armstrong 17.72" (2000 pounder) 100 ton guns (1878) with full hydraulic operation and two rammer systems, the latter to avoid delays in traversing. These systems were not mounted until 1883 nor fully operational until 1886. Unlike the mechanical systems, the detachment for this hydraulic system was wholly protected from both direct and plunging fare, except for the very short length of time it took a gunner to reload the axial vent firing tube!

During the construction of South Australia's system an event occurred which gave the South Australia government second thoughts as to its purchase. This was the report of a fatal loading accident aboard HMS Thunderer, an ironclad mounting an Armstrong hydraulic loading system for two 12 inch RML guns in her fore turret. Steward advised South Australia not to worry. An inquiry and duplicated trial of the other gun later reported that the first gun had been accidentally double-loaded, the simple remedy for South Australia being the marking of the rammer to indicate when each projectile had been loaded to its correct depth in the gun.

Reconstruction

In January 2000 I was invited by the Fort Glanville Historical Association to take up the challenge of creating the mechanical loading system for the mounted 10" 20 ton Armstrong gun at Fort Glanville. Funds at the disposal of the Association had come about through an application for a Centenary of Federation Grant. The amount was a guesstimate, which as things turned out was not far off the mark, thanks to a lot of voluntary labour.

Having carried out a considerable amount of research on the system since 1969, I agreed. My work initially consisted of putting all of my notes and drawings together, followed by a detailed survey of the site. This took several months and many site visits to check and double check the geometry of the emplacement and loading gallery. Some things of note about the site were:--
 The main supporting posts for the rammer system still existed
 complete with plummer-block hole locations. All other timber and
 fittings had been scrapped.

 The rammer sheath where it penetrated the wall for 3 metres had been
 almost entirely removed by the action of termites. This was a blind
 hole and would have posed a major problem to clean out. The holes
 for the other posts and muzzle rest were located and excavated
 (termites again having prepared the site in advance). This meant an
 invasion of the heritage fabric of the fort was avoided.

 The ceiling mounted chain pulley brackets and one pulley still
 existed, fortunately with only minor termite damage to one of their
 wooden supports. To have fixed the problem either the supporting
 beam would have to have been replaced by cutting through three feet
 of lime concrete from above, or by the addition of an intrusive
 steel truss in the arched gallery.


The three pairs of posts in the loading gallery were all in fact leaning 1.5 degrees from the vertical, which did not pose a great problem, but it was then found that the muzzle rest post holes were inclined in the opposite direction. This required cutting the guide posts to lines inscribed by a pencil attached to a template of the cradle running up the posts. It also necessitated the adding of lugs to the cradle hooks to stop them jumping sideways off the guide post hooks as the cradle moved the odd 2 inches (60 mm) away from the posts. No original details of this problem were found, except to say that the hooks shown in the Elswick photograph were not, by the evidence of later photos, the type used.

Since there had been some uncertainty about the actual height of the gun platform originally purchased as opposed to the replica, the site survey resulted in a loading angle of 12.5 degrees (instead of the 13 degrees as planned, or the angle found in the rammer hole in the wall, viz: 12 degrees!) Minor but painstaking adjustments had to be made when it came time to test the motion of the cradle to effect a full alignment of gun, cradle and rammer. One of these minor adjustments allowed for the short dive the gascheck (and projectile) made as it jumped the gap between the end of cradle and muzzle of the gun.

The timber sizes were not of today's standards, moreover suitable timber was generally unavailable and after long delays the major components were made from laminated oregon, up to 8 metres long. The cradle was made from laminated ex-woolstore karri (Australian hardwood) floor joists. As shipwrights were unobtainable for making the cradle, recourse was made to computer aided machining. In hindsight I could have saved a thousand dollars if I had cut the 7 feet x 10 inch (2130 mm x 254 mm) diameter groove by hand with gouges!

Another problem was the actual design of the rammer, was it metal-lined or hollow? I opted for a laminated oregon rammer with a rope groove in its underside and 2 mm clearance. During testing the wire rope drive, having performed perfectly without slippage, suddenly became harder and harder to operate. To my surprise I found that sawdust was being formed by the friction of the rammer against its sheath and was galling up into hard lumps. In effect these lumps were being drawn along by the rammer and gouging long grooves (approx 1.5 mm deep) into the softer shim laminates glued to the sides of the rammer. This was subsequently remedied by thinning down the rammer in situ, it not being timely to withdraw the sheath from the wall for this adjustment. The idea of coating the rammer with a lubricant of any sort was rejected because of the possibility of wind-blown sand sticking to it and thus making matters worse. This problem is being monitored. The interpreter gunners sweep off any gunpowder fouling and sand which falls upon the top of the rammer as it moves outside of its sheath.

The method used to allow for any changes in the height of the cradle axis was to attach an adjustable oregon spacer/buffer to the bottom of the seesaw counterweights.

Following the excavation of the muzzle-rest post holes it was found that water was seeping in beneath the gunblock and filling the almost metre deep holes to a depth of 35 cm. The remedy was to coat the feet of the new posts with fibre-glass.

All steel parts were hot-dip galvanised, cast iron was carefully painted and other parts were of stainless steel (the wire rope for example) and non-ferrous metals.

The gears and pinions of both winches were computer-cut from mild steel to cut costs, with negligible visible detriment to the form of cast gears.

While the staked end of the wire rope is now possibly inaccessible within the bottom of the fort wall, the outer end, after getting rid of any slack, was fitted to a multi-screw clamp behind the rammer head. This was designed to allow for any future adjustment of slack even though the amount of friction of four effective coils of wire rope around the large smooth drum would in any case negate this during rotation.

The rammer head of hardwood laminates was attached to the end of the rammer stave (125 mm x 75 mm in cross section) by a long spring-loaded bolt, designed to cushion any blow to the head when stopped by the sheath. The basine bristled rammer head is withdrawn undercover when not in use.

The two pairs of missing system support posts were all made in halves, fitted into their respective holes in floor and ceiling and joined with some finesse where they straddled the rammer sheath.

To give effect to the demonstration of the apparatus and instead of dummy loading the gun with "service" drill cartridge and shell, I used a hollow pine cartridge (a solid karri cartridge was just too heavy for the interpreters to lift, even though it was lighter than the real thing) and common shell of karri fitted with dummy copper gas check and dummy fuze. During the loading drill the cartridge was linked to the shell, and which in turn was linked to the rammer head. This system of removable steel linkages thus enables the shell and cartridge to be rammed and withdrawn together, thus avoiding the problems of "losing" the components in the chamber by other methods on visitor open days.

The crank handle for the chain winch was copied from those found in the well at the Bluff Battery, Hobart.

Initially it was thought that the stop on the racer fixed the point of traverse for loading, but during testing it was found that this was not so (by 25 mm), this function evidently being obviated by signal between the traversing number and gun captain at the muzzle rest. Traversing and elevating were done by volunteers during reconstruction because the mechanisms did not yet exist.

One of my scaling and proportioning tasks ended up being spot-on, viz: the lever-trolley. Apart from carting projectiles, its special function was to deliver projectiles over the edge of the cradle and lay them in it. For this to succeed the height of the trolley lifting arm and length of selvagee were critical so as not to foul the edge of the cradle. The system is demonstrated on open days at the fort.

I am forever grateful to my assistant on this job who passed away after all the major work had been completed, he unfortunately missed out on seeing the system work.

(1) Journal of the Ordnance Society (UK) Vol. 10-1998.

(2) SAPP (SA Parliamentary Paper) 240/1877.

(3) When in England, Jervois was anxious to purchase an ironclad destined for Argentina, but was unsuccessful.

(4) "C" pivot offers to a Central pivot gun emplacement where the mounting could turn a full 360 degrees.

(5) Rendel Papers 31/5884, Tyne & Wear County Library, Newcastle upon Tyne, UK; and SASR:GRG (SA State Records: Government Record Group) 24/6/1878/1794.

(6) Letter of 18 November 1878 enclosed in Spec. 36/78: Alterations to Semaphore Battery SRSA: GRS 1800.

(7) The 100 ton Armstrong Protected Barbettes in Gibraltar and Malta took gunner safety to even greater heights by the use of hydraulic power. Whereas at Fort Glanville the gunners were exposed to vertical fire during traversing, elevating, compressing, washing, sighting and firing, only the latter was exposed for any length of time at the 100 tonners. These guns were also made in 1878 but were not operational until the mid-1880's!. Rendel had in fact advocated hydraulic systems for loading guns since the early 1870's.

(8) Appendix A to "Australian Defences and New Guinea"--Compiled from the Scratchley Papers, C. Kinloch Cooke, Macmillan, London 1887)

(9) It was not possible to pass through the gallery because of the high steps between the ammunition lifts and trough.

(10) Armstrong protected barbette platforms had two large unflanged trucks (wheels) to run on the racer for the purpose of easier and faster traversing.

(11) The gun being already "up", it consequently avoided suffering any unwarranted shock of hitting the buffers (as in the normal method of loading where the gun was loaded in the "back" position, and thus cause the projectile to be dislodged forward with possible catastrophic results.

(12) The rammer head was fitted with a piasaba brush to prevent gunpowder residue from building up in the rifling grooves.

(13) SASR:GRG 55/1/1880/AG8021, and Report No. 12 of the Special Committee on the Working of Heavy Guns 1881:-PRO (UK) SUPP. 6/530).

(14) This slowed the loading cycle a little, but could have been avoided by using a tighter cartridge, or shorter becket. For reasons unknown the practice of using split charges does not appear to have been adopted, especially considering the weight of the full charge!

(15) The protected barbette guns installed by the Australian colonies of Queensland, Tasmania, New South Wales, and the 100 tonners, all adopted axial vents.

(16) SASR: GRG45/3/1881/TO737 and GRG55/1/1881/AG9481.

(17) The author has been unable to reproduce this problem and can only surmise that the wire rope may have become permanently stretched and not repaired or replaced. Of continuing annoyance was that owing to some further subsidence of the pivot (the gunblock and fort were built on sandhills) one of the guns (the gun since restored with corrective tilted and eccentric pivot collar) now required four men to traverse it.]

(18) The South Australian Register (Newspaper) 31 March 893.

(19) PRO SUPP. 6/530.

(20) This may have been the gun eventually mounted at the Puckpool Battery, Isle of Wight, the unaltered emplacement still existing

(21) The theoretical was apparently still to the fore in the minds of these experts rather than what was reality at that time and for many years to come!
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Author:Garie, Frank
Publication:Sabretache
Geographic Code:8AUST
Date:Jun 1, 2003
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Chesterton.
Lift or grab: identical machines purchased by different operators demonstrate both sides of the grapple versus magnet debate.
Welder Wabi sells safety lift: known for their wear-resistant castings, Wabi Iron & Steel Corp. is selling the world's first steel-guided elevator...
COMING-OF-AGE SAGA REVEALS FROSTY RELATIONS IN AUSTRALIA.

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