TOPIC:

Perhaps fired by the VSM 1-pounder pictured in David's last post?

Brass plate engraved: "Fired by the Boers into MAFEKING. May 10th 1900".
Paper label applied to base of projectile with ink inscription: "Boer Pom Pom shell fired into Mafeking during the Seige [sic] 1899 - 1900, brought back by my father Louis Edward Anderson A.L.B.A."

Surgeon-Major Louis Edward Anderson served with the Royal Army Medical Corps, receiving the QSA with clasps for Defence of Mafeking & Transvaal and the KSA with clasps for South Africa 1901 & South Africa 1902. Note in remarks column of QSA roll reads: "M.O. Protectorate Regiment".






Major General Louis Edward Anderson CB, later Deputy Director of Medical Services Southern Command India.
Born 27/3/1861 at Roden Place, Dundalk. Educated at Dundalk School and Qualified at the College of Surgeons Dublin in 1881. Too young for the army, he sailed as a Ships Doctor for six voyages, 1881-84. He served in the Soudan Expedition December 1884 (Medal with two clasps-Khedives Star).Thence to India and served in the Tochi Valley (Medal & clasp). Served in the South African War as Principal Medical Officer during the Siege of Mafeking (QSA with two clasps, including Defence of Mafeking), KSA with two clasps, MID LG 8/2/1901. Surgeon General 1912. Major General in 1919. War Medal 1914-18 for service in Ireland until 1916, thence India. CB 1913.


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Early handbook for the Vickers Sons & Maxim 1-pounder or "pompom". Published in 1893, this example predates the 1897 merger of Maxim Nordenfelt and Vickers, and the formation of Vickers Sons & Maxim. Pre-merger, the "pompom" was simply known as the "Maxim 1 1/2 Inch Automatic Gun".








VSM Vickers Sons & Maxim 1-pounder (Vickers-Maxim pompom)

Early handbook for the Vickers Sons & Maxim 1-pounder or "pompom". Published in 1893, this example predates the 1897 merger of Maxim Nordenfelt and Vickers, and the formation of Vickers Sons & Maxim. Pre-merger, the "pompom" was simply known as the "Maxim 1 1/2 Inch Automatic Gun".
















VSM Vickers Sons & Maxim 1-pounder (Vickers-Maxim pompom)

Members of the Staffordshire Regiment with their Vickers-Maxim 1-pounder. The Staffordshire Knot has been laid out in whitewashed stones on the hillside behind.

Note the belts of 25 rounds, coiled on top of their ammunition boxes, to left and right. The handbook in my last two posts shows belts of 50 rounds. I am not sure whether both lengths were available at the the time of the ABW, or whether the 50-round version had become obsolete.



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Background

The construction of an artillery piece in Kimberley that would have a range similar to the guns of the besieging force was the idea of the American engineer George Labram. The former Chief Engineer of De Beers Consolidated Mines Ltd believed that a billet of steel that had been bought for shafting could instead be bored to make a gun barrel. As the mild steel of the billet was much lower in carbon than would normally be supplied for barrel making, iron rings would have to be shrunk on to strengthen the piece.

Despite initial resistance from the military authorities, Cecil Rhodes, Chairman of De Beers, gave the order for the attempt to make the gun on Christmas Day 1899. Just 24 days later "Long Cecil" was ready for testing and ranging. On 23rd January the gun saw action for the first time when it fired the first of some 255 shells into the Boer lines.




George Labram, Chief Engineer, killed 9 Feb 1899, 2nd from right; Edward Goffe, Chief Draughtsman, far right








After the end of the siege, on 15th February 1900, Long Cecil wasn’t to be used in action again. Now an object of curiosity, in August 1901 the gun was transported to the Cape for the Royal visit of the Duke and Duchess of Cornwall and York (later King George V and Queen Mary). In the spring of 1902 it was used to carry the mortal remains of Cecil Rhodes during the funeral procession through the streets of Cape Town.

After the war, Labram’s gun was returned to Kimberley where it was incorporated into the Honoured Dead Siege Memorial, which was dedicated on 28th November 1904. There it remains to this day.






Photographed in 1981



The Models

On 28th June 1900, Edward GOFFE, A.M.I. MECH. E., Chief Draughtsman at De Beers, delivered a paper at a meeting of the Institute of Mechanical Engineers, London, titled “Notes on the Construction of ‘Long Cecil’, a 4.1-inch Rifled Breechloading Gun, in Kimberley, During the Siege, 1899 – 1900”.
The paper included a series of detailed measured drawings of "Long Cecil". These would be used by model-makers over the coming years.

During the first months of 1902, George F. Williams, General Manager at De Beers, ordered a batch of presentation scale replicas of "Long Cecil" from the American firm of Pratt & Whitney Co., Hartford, Connecticut, USA. These are believed to be the first models of the gun. An example of this 1902 edition is held in the collection of the Institute of Mechanical Engineers, London. Another was sold through AntiquarianAuctions.com on 13/07/2017, and, according to Wikipedia, a third was presented to the American Society of Mechanical Engineers. Each model was mounted in a glass case, with a silver plaque, inscribed: “EXACT REPRODUCTION OF / “LONG CECIL” / MADE AT KIMBERLEY SOUTH AFRICA, / DURING THE SIEGE, 1899-1900. / SCALE 1 TO 12. REPRODUCTION BY / PRATT & WHITNEY Co / HARTFORD, CONN.” An article in the Allentown, Pennsylvania "Morning Call" of 02/04/1902, states: "The models, complete reproductions in every detail, were made at the Pratt & Whitney Works, Hartford, Conn., by order of George F. Williams, Manager of the DeBeers mines, for presentation to her late Majesty, the Queen of England; Lord Roberts, Mrs Labram, the widow of the American designer, and others".
This was the beginning of a tradition of "Long Cecil" model-building that continues to this day.

Ten years after Edward Goffe's lecture in London, Mr POLLARD, an amateur model-maker, published photographs of a replica of the gun in The Model Engineer and Electrician (24 Mar 1910). However, his photographs were not accompanied by plans, and it wasn’t until 1st January 1914 that a full set of 1/16 scale drawings, with notes for construction, was published by Charles BAGLIN in the same journal. These drawings were based on the plans published in Goffe’s paper of 1900.

Meanwhile, during 1910, a further example had been built by William Newman in the Kimberley workshops, the scene of the construction of the original cannon. This gun was sold through Old Johannesburg Warehouse Auctioneers on 08/08/2018.

It is worth noting that the Pratt & Whitney models used single inter-spoke rivets for tyre attachment, a method that was true to the original design, whereas Baglin's drawings show two rivets between each pair of spokes. The latter (incorrect) method of construction is a distinctive feature of models made using the 1914 plans. The fact that Goffe's paper had not included drawings of the wheels probably contributed to this error. Goffe had not been involved in the design of the wheels as they had been sourced from elsewhere and were not made in the De Beers workshops.
The Pratt & Whitney models were also larger, being constructed at 1/12 scale opposed to 1/16.

The example at the top of this post was made using the 1914 set of drawings and dates from that period.
More recently Zane and Anita Palmer have picked up the mantle, and are building beautiful 1/12 scale models of "Long Cecil" in South Africa. SEE: Palmer's Armoury . These draw inspiration from Goffe's 1900 drawings and the 1914 Model Engineer article.
Kimberley Engineering Works (Pty) Ltd also made a small number of models for the 1999-2002 Centenary. These were made according to the 1914 Baglin specification.







The object in view was to make a gun of greater power than those possessed by the garrison, which were 2.5-inch R.M.L. guns (7 pounders), and were not big enough to effectively reply to the enemy’s 15 pounders, or to make any impression on his works.

A gun of about 4 inches bore, firing a shell 25 lbs to 30 lbs weight, appeared to meet the case, and to be possible of construction.

The possession of a billet of hammered mild steel (originally intended for shafting and ordered as such), 10½ inches diameter and 10 feet long, made by Messrs Sybry, Searls and Co., of the Cannon Steel Works, Sheffield, and of several bars of 6-inch by 2½-inch Low Moor iron, in the workshops of the De Beers Consolidated Mines, really suggested to the late Mr George Labram, chief engineer to the Company, the possibility of making the gun, by boring the steel bar to form the tube, to be strengthened by rings shrunk on, made of the Low Moor iron. The makers of the billet subsequently wrote that the steel, from which the inner tube was constructed, was originally intended for shafting, and was considerably lower in carbon than they would supply for the purpose of making gun barrels. Tensile tests from this steel would have resulted somewhat as follows: – 27 to 30 tons per square inch breaking strain, with 20 to 35 per cent elongation in a length of 8 inches, with 40 per cent reduction of area.

The resulting gun would evidently be of a type similar to an early “Armstrong”, heavy for the work done compared with one of a more modern type, but in this case, weight was a minor point to be considered, ease and quickness of manufacture being perhaps the leading ideas.

The first difficulty met with was the resistance of the military authorities to the attempt to make the gun, but as this was hardly a mechanical difficulty, further reference to it may be out of place. However, on Christmas Day 1899, Mr Rhodes, Chairman of the Company, gave the order to Mr Labram to make the attempt. Work was immediately started, and then the difficulty consequent on ignorance, on the part of both Mr Labram and the author [Edward Goffe], of practical gun design, was first met with. This was overcome by a search in all books available, and the scattered information so obtained brought together. The sources of information were: – The articles on Gunnery, &c., in the Encyclopaedia Britannica; the Military Treatise on Ammunition (which had previously been used in gaining information to make shells and cartridges for the 2.5-inch guns earlier in the siege); Articles on Modern Guns in “Engineering”, &c.; and from the military “Textbook on Gunnery”, brought forward by an enthusiastic volunteer officer, and which proved very serviceable. During the progress of the work in the shops, assistance was also given in many details of gun-shop practice, the form of special tools used, &c., by several of the employees there, whose previous experience in Woolwich Arsenal, the Elswick Works, and elsewhere, was willingly given to forward the work in hand.

Approximate calculations only were made, for two reasons, one that it was not considered necessary to go into very fine calculations when the two principal factors, the powder pressure and the test strengths of the materials to be used, were not known, and could only be estimated, recourse being preferably made to comparisons of the performances of similar guns. The other reason was that time was pressing – the designing, and supplying of sketches going on simultaneously with the making of the gun in the workshops.

The stock of powder in the town was of many kinds, ranging from “mealed” to compressed cylinders 1⅜ inch diameter by 2 inches long. Most of it had been kept for a long time, much of it over ten years for certain, but it did not appear to have deteriorated, still retaining a good glossy surface.

The cylinder powder (black) was evidently the most suitable for use, but there was not very much of it, so preparations were made to compress the finer powder into blocks, and so form a slower burning powder. The possibility of the compressing not being successful when the stock of cylinders was exhausted, and of having to use all kinds, had to be faced, but there proved to be sufficient cylinders to provide cartridges as long as the gun was fired.

From data available it appeared that 50,000 lbs to the square inch would be a suitable maximum pressure to allow for, that being about the maximum pressure calculated, when using a charge of 5 lbs of powder in the space which would be available for a powder chamber. But while using the slow-burning powder the shell presumably would begin to travel before that pressure was attained. Many charges of 6 lbs were used while the gun was in action, the maximum pressure due to these conditions appearing to be about 90,000 lbs per square inch, but for the same reason, probably the actual pressure reached would not much exceed that obtained from the use of the smaller charge.

A powder chamber of 4.25 inches bore it was found would just contain seven cylinders of powder, four of 1⅜ inch diameter, and three of 1⅛ inch diameter, their combined weight for 2 inches of length being just 1 lb. With this diameter of chamber, to obtain a normal air-spacing, the length required to be about 12 inches. Next the breech screw must necessarily be about 5½ inches diameter, and allowing a length of thread equal to 1¼ diameters and about 2 inches for obturator, the length of the breech block would be, say, 10½ inches. The total length of the steel billet was 10 feet ¾ inch, so deducting from this 1 foot 10½ inches, the length available for the bore was 8 feet 2¼ inches, very nearly 24 calibres in length.

Upon this basis the strength was next figured out, and the tube alone first taken. Using a formula for the strength of a thick tube subjected to 50,000 lbs per square inch internal pressure, the greatest stress in the material was found to be 70,000 lbs per square inch. This showed, as was expected, that the tube could not be used without shrunk rings.
By shrinking on two rows of rings, each 2 inches thick, a reduction of the greatest stress in the tube to about 40,000 lbs per square inch, and that in the rings to 20,000 lbs per square inch, was calculated, and that it was considered safe to allow. That there was sufficient strength was evident; but the author would like to know really what pressure was attained at any time, the only sign of strain being that the powder chamber has enlarged slightly and is now barrel shaped, the diameter of the centre being fully 1/32 inch greater than as originally made. This is apparently due to direct compression of the metal, as the outside diameter was carefully gauged when an opportunity was given by some of the rings being removed, and was found to be exactly as made.

The order to make the gun was received on the evening of Christmas Day, 1899, and at the start of work next morning the billet of steel was taken into the machine shop. A lathe of 12 inches centre with bed 14 feet long was used, the extra length of bed required for working the boring bars and rifling gear being obtained by the use of the bed of a similar lathe set in line with it, with the headstock removed. This was already in position, being used when working on lengths of shafting, &c.

Most of the men required on the work had to be temporarily withdrawn from the redoubts where they were stationed, forming part of the Town Guard. During the building of the gun and making of ammunition, the workshops were always under fire from the enemy, many shells, including 94-pounders, bursting around and passing over the buildings, none however actually doing damage; but it was very trying for a man to stay at work at a lathe or other machine, hearing shells bursting around, and not knowing whether the next would come inside or not, and all those who had that experience deserve appreciative mention for the way in which they stuck to their posts.





Fig. 2, Plate 40, shows the general construction of the gun. The steel billet was first turned all over outside, a shoulder of ⅛ inch being made to take the thrust of the trunnion ring, the largest diameter being 10.5 inches. It was turned tapering towards the muzzle, a parallel part about 9 inches long being left there to be used as a journal when boring. For boring, the breach end was held in a dog chuck with the muzzle revolving in a hard wood bearing, and first a twist drill 1½ inch diameter put right through. This was followed by a twist drill 3 inches diameter, then the end counterbored with a tool and a boring bit, Fig. 7, Plate 41, started, enlarging the hole in one cut to 3 15/16 inches diameter. The bit was plentifully supplied with water through the bar, which was one belonging to a diamond boring drill. All went through without any special difficulty, but experience showed that the boring cut was too heavy, and it would have been better to have taken two cuts for that amount.

While the turning and rough boring were being done, which occupied about a week, the rings were being forged, nine being wanted for the first row, 10¼ inches diameter inside (less shrinkage), and four wanted for the outside row, about 14¼ inches diameter. These were all made from the 6-inch by 2½-inch Low Moor iron, a length of bar being cut, bent to a circle, and the ends welded together. As these were finished they were passed on to the machine shop, where they were turned, faced, and bored to gauge.

The trunnion ring was a greater undertaking than the plain rings, and the difficulty of making a satisfactory weld in so heavy a piece of work, with the appliances at his command, was overcome by the leading blacksmith, by working it out of a length of 6-inch by 6-inch Low Moor iron, starting a small hole through the centre, and enlarging by successive heats until he had it to the required size for machining.

By the time the rings of the first row with the trunnion ring were made, the tube was ready to receive them. For shrinking, the tube was held vertically under a convenient derrick in the yard, first with breech end upwards. The ends of the bore were plugged, and a circulation of cold water arranged inside to keep the tube cool. The rings were heated on a plate over a wood fire, the bore being gauged until sufficient expansion was evident, then lifted by the derrick over the end of the tube and drooped into place, the trunnion being the first to go on, resting against the shoulder. As a precaution against possible travel endways while cooling, each ring was clamped by longitudinal bolts, and the adjoining one on which it rested kept cooled down by a stream of water from a hose pipe. The table was reversed to put on those rings in front of the trunnions, and, the whole of the first row being in place, it was returned to the lathe, and the outside of the rings turned up to form a seating for the second row over the powder chamber. The process of shrinking these was the same as for the first row, and when they were on, the barrel was again returned to the lathe for finishing.

The final boring was then begun, the tool used being a studded bit with double-ended cutter, Fig. 8, Plate 41.





Meantime, the question of rifling had been gone into, and, the increasing twist appearing more desirable and easier on the gun than the uniform twist, it was decided to make it so. To effect this the rifling attachment, as shown in Fig. 6, Plate 41, was devised, the idea being given to the author by remembering one of Sir W. Anderson’s lecture diagrams. The author has since learnt that this method is still used in gun factories. The drawing shows a channel-iron bolted to two cross channels, which are bolted to the ends of the lathe bed. On this channel-iron the developed curve of the spiral – a semi-cubical parabola – was set out by its ordinates. A planed bar to act as a forme was bent to the curve, and screwed down with countersunk screws. The hardwood blocks, forming the guides to the rack, and bearings for the rifling bar, were bolted solidly together and to the saddle of the lathe. The end of the rack (which was a stock one as used on the washing machines) is furnished with one little roller, travelling on the “forme” bar, contact being kept by a cord attached to the underside of the rack, carried over a pulley at some distance and having a weight at the end. A small guide pulley should be shown on the saddle to allow for vibration of cord with travel of saddle. The traversing of the saddle was done by the leading screw of the lathe, a small belt pulley being put on in the place of the usual “change” wheel, with a belt from the overhead drive.

A detail of the rifling head 1/10th full size, is shown, Fig. 9, Plate 41. It was formed of a solid block of steel, turned to fit the bore of the gun, into which the end of the rifling bar was tightly screwed. The tool was able to revolve slightly on its pin as a centre, being kept up to the position by the set screw and packing block, which also regulated the depth of the cut taken, while clearance on the return stroke was possible by the giving of the spring. A felt pad held by a washer was attached to the head in front of the tool, while the head drew another wad of felt behind it, to clean the bore of cuttings as made, and a supply of soapy water under pressure was forced in behind the head, the two semi-circular grooves being provided to allow the supply to get to the cutting edge. The only serious trouble experienced in the workshop processes was at this point, when it was found most difficult to get the tool to cut properly, and a lot of time was spent in trying to find the reason, three grooves only being got through between about ten o’clock one morning and late the following night. The material could not be at fault, as it had been found perfectly good, without flaws, and very clean cutting up till then, and new tools and different lubricants were tried, but with no success, until the packing block, which took the pressure of the tool, and which consisted of a small piece of iron, was noticed to be denting, when a new one of cast steel hardened was put in its place, and no further troubles were experienced, the remaining twenty-nine grooves being finished in about eight hours from then.

The rifling was started from the extreme end of the barrel at the breech, so that there was about 2 feet of length to spare, to be afterwards bored out for breech and powder chamber, so that should a false start have been made with a groove by accident, no damage would have resulted. After rifling, the bore was lapped out to take off any roughness left by the tool, and then reversed in the lathe and the powder chamber bored out, a double-ended tool similar to that shown by Fig. 8, Plate 41, being used.

The breech-block screw having meanwhile been made, the inside was cut, and the block fitted in. In cutting this thread in the barrel, the question of the ending of the cut inside had to be met, and the simplest way seemed to be to let the tool finish in a clearance hole, and to drill this hole inside: the little drilling machine, Fig. 10, Plate 41, was made, being worked by a gut band from a convenient source of power.

The breech-block and obturator are shown in detail in Figs. 3, 4 and 5, Plate 40. The De Bangé system of obturation was adopted, that appearing to be most the efficient and easily made. The obturator pad was made of rings of sheet asbestos soaked in melted tallow, and proved quite successful. The breech-block as made first and used with radial firing is shown in Fig. 3. The block was of hammered mild steel, the same material as the tube of the gun, screwed with a “V” thread of ¾ inch pitch with flattened top and bottom. The handle-bars and plate are one forging, fastened to the screw with six tap bolts. The obturator bolt with mushroom head was made of mild steel, 1½ inch diameter shouldered near the middle to 1¼ inch diameter, and held by lock nuts in a recess at the back. As thus made about 100 rounds were fired with this obturator. Figs. 4 and 5 show it as subsequently made, the reasons for which alterations will be described in due course.

It was arranged originally to have an interrupted screw, cut away in three sections, so that one-sixth of a turn of the handle-bar would release the breech-block; but consideration of the time to be saved by not cutting it, which it was thought would be at least two days, and the further consideration of strength, induced the author to urge keeping the screw intact, the actual extra time taken in unscrewing the whole way being only a few seconds.

With the interrupted screw, a safety-vent closing device was necessary, and one was made. One handle, as turned to unscrew the block, moved a plate sliding on the end of the barrel, which by means of a pin working in a diagonal slot closed the vent with a light plate, the reverse action taking place when the handle was turned to screw up the breech, so that the vent could only be open when the breech was tight. With the plain screw this was not so urgently required, and although the guard over the vent was retained for a time, it was not used. The vent hole was drilled in the gun barrel after the powder chamber was bored and the breech fitted, and was ¾ inch diameter. About an inch at the top was tapped with ½-inch gas thread, and a copper plug fitted as tightly as possible for the whole length being screwed at the end to fit the hole. This copper plug had a small hole drilled through it to fit the friction tubes used.

A relieving hole ½ inch diameter was also drilled through the underside of the barrel from just behind the obturator, to prevent any damage to the thread from the product of explosion, should the obturator ever act imperfectly. But at no time during firing was any smoke noticed coming from it. A flat place true with the axis of gun was planed on the top for standing a clinometer upon. A gun-metal casting bolted to the underside was cup-shaped to fit the end of elevating screw, which was turned to a ball. This it was found necessary to replace by a hinge joint, as the gun jumped on firing, and the elevating screw when in an inclined position tended to fall over, and the cup did not come fairly on to the ball end. The back sight, copied from that of one of the 2.5-inch R.A. guns, was provided with a fine traverse for wind allowance, &c., and was set at an angle of two degrees from the vertical (to the right) to allow for “drift” of shell, which was found on firing to be almost exactly correct. The front sight on the trunnion was first made as a bead in a small tube, but was afterwards altered to a knife edge without the tube. This completed the gun itself, ready for mounting on its carriage, as first turned out of the workshops.

Carriage. – The carriage having been made in the meantime was ready for the gun. Its general construction is well shown in the accompanying photograph, Plate 39. It was formed of four steel plates ¼ inch thick, cut to shape, riveted together in pairs, 2½ inches apart, with distance sleeves on the rivets, and with gun-metal castings also acting as distance pieces and riveted in, for trunnion and axle bearings. The two pairs of plates were bolted together with shouldered bolts, 17¼ inches apart, and with a rubbing plate at the trail end, which was also provided with an eye for hanging to limber. The elevating screw was of steel, 2¼ inches diameter, with square thread ¼-inch pitch, working in a nut pivoted between the side frames, and provided with a hand-wheel. The axle was 4½ inches diameter keyed into the side frames.

The wheels were the only part not actually made, and they were a pair belonging to a potable engine and suited the purpose admirably. They were bored out, had gun-metal bushes driven in bored to fit the axles, and brass dust-caps screwed on outside. The height of the centre of the trunnions from the ground is 5 feet. The centre of the trunnions is 5 inches behind, and the point of contact of the trail with the ground 9 feet 6 inches behind, the vertical line through the axle, and the wheels are 5 feet centre to centre.

With twenty-four days of continuous work the gun was ready, and on the 19th January 1900 it was taken out for testing and ranging, a firing platform and redoubt having been built at No. 2 Washing Machine, Kimberley Mine Floors, whence the Boer headquarters (the Intermediate Pumping Station of the Kimberley Waterworks Co.) and several of their gun positions could be commanded. The ranging was done with the assistance of the Company’s surveyors, one having a theodolite at the point of firing, while another, also with a theodolite, was stationed at a point about a mile distant, nearly at right angles to the line of fire. On firing each took observations of the spot the shell struck, and the angle of firing as shown by clinometer, time of flight, charge of powder, &c., also being observed and tabulated, the muzzle velocity was calculated, and range tables made for subsequent use, by Mr C.D. Lucas. The back sight was not graduated for range, only being used for laying the gun, the firing party preferring to use the clinometer. The enemy appeared much disturbed when the first shells burst in their headquarters, and could be seen hurrying out in all directions, not expecting that they could be reached there, and there was no reply from any gun of theirs during the ranging trial. Mr Rhodes was present the whole time and personally fired most of the shots, being very pleased with the performance of the gun, and the artillerists working it were well satisfied with its shooting qualities. The trials having been completed, the gun was returned to the workshops for one or two minor alterations, including a new front sight and altered attachment for elevating screw, as already mentioned. These having been completed, the gun was handed over to the firing party and was in action on the 23rd January.

While in action 255 shells were fired in all by it, most of them being at ranges of 5,000 and 6,000 yards, these being reached with elevations of 12° and 15° respectively, with a powder charge of 5 lbs, the shell being 29 lbs in weight. With the same charge a range of 8,010 yards was reached with an elevation of 24° 15’.




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An early example (first quarter of 1902), built by Pratt & Whitney Co., Hartford, Connecticut, USA, on display at the Institute of Mechanical Engineers, London.
"The models, complete reproductions in every detail, were made at the Pratt & Whitney Works, Hartford, Conn., by order of George F. Williams, Manager of the DeBeers mines, for presentation to her late Majesty, the Queen of England; Lord Roberts, Mrs Labram, the widow of the American designer, and others" (Allentown Morning Call, 02/04/1902).




A second Pratt & Whitney model; this example sold through AntiquarianAuctions.com on 13/07/2017 (with thanks to Paul Mills).
Note the single inter-spoke rivets for the tyre attachment, which are true to the original design. The 1914 drawings show two rivets between each pair of spokes, and this (incorrect) method of construction is a distinctive feature of the models made using the Baglin plans.



Gun made by William Newman in the Kimberley workshops in 1910 (with thanks to Old Johannesburg Warehouse Auctioneers)






One of Zane and Anita Palmer's models ( Palmer's Armoury )


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