More seriously, War Office experiments on 6 November 1915 tested the ability of powerful water jets to destroy trenches and incapacitate their occupants. The trials took place in Scotland at the Kinlochleven works of the British Aluminium Company. Water at 400lb per sq in at the delivery nozzle was pumped through steel pipes and directed on to lines of German-style trench works up to 150yd away. The force of the jets lifted parapet sandbags 12ft into the air and flung them 30ft. The blast of mud and stones would have killed or disabled the defenders and jammed their light weapons. However, the operation required some 3,000 horsepower of generating capacity plus heavy turbo pumps, thousands of feet of steel piping (which would have been vulnerable to shellfire) and a large water supply. Kinlochleven was no whimsical stunt. A detailed trials report was on the Prime Minister’s desk and in the hands of the Committee of Imperial Defence within three days, but hydraulic artillery was judged impracticable and the scheme was dropped.3
By December 1914 British killed and wounded had reached 90,000, exceeding in number the strength of the seven divisions of the British Expeditionary Force (BEF). The highly professional Regular Army effectively ceased to exist at the close of its victorious defensive stand with the French at First Ypres in mid-November.
The origins of the deadlock in Belgium and northern France lay in the wreckage of the strategic plans of the French and German general staffs. Their preparations had relied on maintaining a war of rapid manoeuvre supported by the rail system. There was no expectation of or provision for protracted siege warfare, for which their armies and the BEF were untrained and, in varying degrees, ill-equipped. Germany’s Schlieffen Plan and the French counter, Plan XVII, hinged on mobility and speed of attack. When the two armies fought themselves to a standstill, both sides dug in and the Germans threw up hasty defences with whatever came to hand. Their troops stripped farms of wire, fence posts, sheet iron – anything to slow rushes of men and deflect them towards the Maxims. Thickening belts of barbed wire soon followed. The machine gun came into its own.
The few British machine guns were dispersed, two per battalion. More often than not they were under command of a subaltern who was sometimes the only officer in the unit with any knowledge of how to use them. The Germans had ensured that every Jaeger battalion and infantry regiment included a specialist machine-gun company of six guns. These groups were free to deploy to greatest tactical advantage. One such company could match the firepower of an entire infantry battalion.
Over the next three years every Allied offensive was either beaten back to its start lines by the Maxims or cost a terrible price in blood for the ground gained. For most of that period the British and French staffs remained confident that artillery could shred wire defences and smash machine guns if enough fire was put down. The assumption was tragically false, but the reality was obscured in the BEF by a prolonged shell shortage of all calibers which became acute as early as the end of October 1914. Ammunition for 18-pdr field guns was then down to an average of seven rounds per gun per day. Most of it was shrapnel for open warfare rather than the high explosive needed to destroy trenches and heavily roofed bunkers and weapons pits.
Munitions production was geared to the modest pre-war policing requirements of the Empire. Too often the guns of the BEF had little or no ammunition even to return fire. By April 1915 Britain was producing 2,500 high-explosive shells each week. French output was 50,000 per day.4 Four months later British output had improved fractionally to eight rounds per gun/day, while the army was calling for 17 rounds.
The hiatus in high-explosives supply had been foreshadowed by an incident during the last weekend of peace. Maj Gen Sir Stanley von Donop, Master General of Ordnance, was responsible for supply of the army’s gun ammunition. On that August Saturday, Prime Minister Asquith had refused von Donop’s request to buy cordite. Permission was finally given the following Monday by Lord Kitchener, the War Minister. Von Donop then discovered to his horror that Winston Churchill had just bought up all available stocks of cordite propellant for the navy – on the Saturday.5
It became chillingly clear to some divisional commanders that massed artillery alone could not prepare lanes for an infantry advance. The guns were incapable of shredding enemy wire and knocking out sufficient Maxims in the initial phase. If an advance was gained despite this, the gunners could not bring up their ordnance quickly enough across shell-torn ground to get back into range and give fire support before the enemy counter-attacked the newly taken positions. It was well understood on both sides of the Channel that Army Council policy was to avoid the production of new weapons and equipment unless previously requested by the Force Commander, Field Marshal Sir John French. Although French implicitly acknowledged the need for a new device when, at the end of December 1914, he approved the development of an experimental armed and armoured trench-crossing machine which laid its own bridge, the project was not taken seriously in France or London. GHQ continued to blame the shell shortage rather than the limitations of artillery.
The War Office did not commit itself to devising a mechanical solution to the stalemate until the summer of 1915, and then only after discovering that others had taken the initiative. That year closed with the resignation of Sir John French and his replacement by the commander of 1st Army Corps, Gen Sir Douglas Haig. There came a dawning realization among some in the Army High Command that if there was to be any chance of a breakout in 1916, the infantry were going to need the support of some kind of cross-country armoured fighting vehicle. But no such machine existed in the British or any other army.
Against this background of rising casualties, mounting public concern and military inertia, a handful of men began the battle to design and build the world’s first tanks. But what was the state of chain traction in 1914? Was the British Army involved in its development? Had it already adopted the system? And what of the other combatant armies?
Many of the answers lie in the activities of a small War Office transport research group. Its experiments in the decade before the First World War included the appraisal and development of tracklaying machines. These early trials and the personalities involved would influence the speed, direction and control of the wartime researches which finally produced the tank.
A Military Transport Committee (MTC) had been formed by the War Office in 1900 during the South African War. It coincided with growing interest in the wider possibilities of the internal combustion engine and a surge of popular enthusiasm for the automobile as it entered the new century. Lord Roberts, the Commander-in-Chief, was heavily reliant on the Road Transport Corps of the Royal Engineers to steam-haul his heavy howitzers, field guns and supply trains across the veldt. They had been joined by Lt Col Rookes Evelyn Bell Crompton, a veteran pioneer of overland steam traction. Crompton was a truly remarkable product of his age and a gifted entrepreneur who would later be in at the tank’s birth. As a Rifle Corps subaltern in India years before, Crompton’s ideas for long-distance steam haulage in place of bullocks had interested the Viceroy, Lord Mayo. With his support Crompton inaugurated a steam road-train service in 1872. It so impressed Lord Roberts that when they met again 28 years later in South Africa he appointed Crompton his Controller of Mechanical Transport. Roberts pressed the War Office hard to expand the Road Transport Corps and sent Crompton back to London in September 1900 to add urgency to his appeal.
The MTC was created in November to consider reports on steam transport in the South African War and to evaluate the respective merits of steam and motorized vehicles of all kinds for the army. Its six members included Crompton and representatives from Ordnance, Quartermaster’s, Engineers and Service Corps departments. Crompton also joined an experimental sub-committee with Maj Henry Holden, Superintendent of the Royal Gun Factory at Woolwich Arsenal, an artilleryman, engineer and motor enthusiast whose inventiveness was recognized by War Office awards totaling £14,800 by the time he retired in 1912. The two worked together developing new military vehicles until Crompton left the committee in
1905. Holden stayed on, by then a lieutenant-colonel, and subsequently he became President of the MTC. The two men later powerfully influenced the initial course of tank development, but from diametrically opposed viewpoints.
One has to remember just how new and unfamiliar the technology was. The War Office prohibited petrol engines for motor transport, fearing the fire hazard in fuel storage and movement. The first lorries purchased by the MTC in 1903 were paraffin (kerosene) oil fuelled, and the petrol embargo continued for several more years. When the committee started work, knowledge of chain traction amounted to little more than a handful of learned papers and, in Britain, some 16 patents. In the USA three patents were granted between 1886 and 1890. A few crude tracked machines had been built in England over the years, attracting negligible interest. The earliest patent for endless chain tracks issued by the London Patent Office is No. 277 dated 1691. Another dated 1770 was secured by Richard Lovell Edgeworth who registered a portable railway comprising short lengths of wooden track fitted to wheeled vehicles, apparently forming an endless chain. Nothing more was heard of it.
More ambitiously, John Heathcote, MP for Tiverton, patented a 30-ton tracked steam ploughing engine in 1832. It was first demonstrated at Red Moss Bog near Horwich, Lancashire in 1835, and Heathcote claimed it could plough 10 acres of marshland in 12 hours. A steam engine with a cable winding drum was mounted on a platform with a pair of 8ft wheels ahead and astern. The whole rather improbable assembly was encircled by a canvas belt fitted with wooden slats, and it worked for a time. The machine was abandoned in a Scottish marsh two years later but it was a true tracklayer and, literally, broke new ground in steam ploughing systems.
Numerous ideas were floated throughout the 1800s for spreading load on soft ground. Most were for attachments fitted directly to wheels, generally as flat, hinged paddles set at a tangent to the wheel which rolled over each in turn as it was presented to the road. James Boydell successfully fitted several Burrell steam traction engines with footed wheels on this principle in the mid-1800s, an observer remarking that it was a pretty sight to watch the action of the shoes, not being heel-and-toe, but sudden and flat, the whole surface of the shoe reaching the ground and again leaving it simultaneously. Boydell’s ‘Steam Horse’ road locomotive easily hauled four or five wagons totaling 50 tons, but the problem with the first machines was the need to put a horse in shafts at the front for steering. A horse unfamiliar with the machinery often refused to start precisely when the machine moved off, resulting in the surprised beast being push-started while it dug in its heels until it ended up in a sitting position. Later types replaced ‘horse power’ with a steersman positioned in front of the boiler at a ship’s wheel. Several of Boydell’s road locomotives went out to the Crimean War for haulage work.
None of these concept machines progressed much further. The MTC concluded in 1902 that steam power for transport was generally superior to horse haulage. Chain traction and the internal combustion engine were not even mentioned, but they soon saw a need for a wheeled motor tractor which would avoid the steamer’s reliance on frequent stops for refuelling and water. The War Office accordingly announced a competition with a £1,000 prize for any tractor which could haul 25 tons 40 miles non-stop. The contest was postponed until 1903 for lack of entrants. In the event only one machine materialized – a conventional-looking traction engine powered by a 70bhp oil engine submitted by Richard Hornsby & Sons of Grantham, Lincolnshire. As it trundled on another 18 miles before the permitted weight of fuel ran out, the company won a further £180. However, the MTC was not an executive department. It had no engineering resources and operated on a shoestring budget. It relied heavily on the goodwill and sales expectations of commercial vehicle builders whose efforts were almost exclusively concerned with civil markets.
Hornsby’s Managing Director David Roberts, a superb design engineer, had been working on a chaintrack system which he patented in July 1904. Construction of a prototype followed. His No. 1 tracked machine was shown informally to MTC members the following summer. It was officially demonstrated at Grantham on 13 February 1906 and sparked a long-running gun haulage debate on the respective merits of crawlers vs horse teams. Roberts had mounted his system on an 1896 Hornsby steam tractor converted to a single-cylinder 20bhp paraffin engine. The 16-ton testbed was seriously underpowered and, rather disconcertingly, its steel frame flexed so much while climbing a marsh bank that the engine bearings went out of alignment and stalled the machine. A laborious process with jacks and planks followed to level the frame before restarting. The crawler then easily crossed trenches up to 4ft wide and hauled a 10-ton load over soft sand, neither task being achieved by a competing wheeled 70bhp steam tractor which only attempted three of the ten obstacles on a very testing course, despite its greater power. The committee was impressed.
… this tractor demonstrated to the Committee its peculiar powers to move over ground that would bring any tractor fitted with ordinary wheels to a standstill… The Committee are of opinion that this vehicle, rough as it is, and unsuitable though its engine may be, is in its power of traversing ground difficult and even impossible to other engines, a marked advance upon anything that has heretofore been manufactured… It would appear to approximate to the ideal tractor for military purposes that we are looking for.6
The essence of the crawler system is its large bearing surface or footprint as compared with that of a wheel, and its consequently greater ability to spread load over soft ground. Roberts curved the lower section of his track to the equivalent of a wheel 37ft in diameter. If the tracks still sink then proportionally more of the curve comes into ground contact, further distributing load and reducing ground pressure. The big-wheel profile also reduces ground contact on firm surfaces which saves power and track wear, especially from ‘scrub’ when turning.
The demonstration machine was too light and underpowered, so for reasons of economy Roberts was asked in August 1906 to convert the old wheeled prizewinning Hornsby, which the MTC had purchased for £2,500 following the endurance competition. It was given an improved version of Roberts’ tracks before trials began at Aldershot in July 1907. The soldiers immediately christened the 70bhp No. 2 machine the ‘caterpillar’. Roberts also wanted to produce a tractor/trailer combination, all on chaintracks, which could carry rather than haul guns over badly broken ground. The MTC referred him to the Royal Artillery to whom he demonstrated the first trailer that November.
Further trials followed in 1908. The 20-ton crawler and trailer took part in the Royal Review at Aldershot that May to the profound astonishment of all present, including King Edward VII and the Prince of Wales, to whom Roberts was presented. A dummy gun was mounted on the trailer at the suggestion of Maj Donohue, an influential member of the MTC. The unsilenced, shatteringly noisy and smoking beast topped by a white-faced Army Service Corps driver clawed its way across the Rushmoor arena, its heavily shod track plates spraying clods of turf rearwards.
The thing was an instant sensation. It was almost beyond the imagination of the public and attracted wide interest at home and abroad. ‘A motor car that can walk over swamps’ was a typical caption. The Morning Leader observed prophetically: ‘Here is the germ of the land fighting unit when men will fight behind iron walls.’ That summer London’s Empire Theatre gave bioscope screenings of a Hornsby film clip which climaxed with a horse and cart traversing a reed swamp. The horse sank to its withers, whereupon, to the stupefaction of the audience, the caterpillar hove in sight and effortlessly cruised over to haul out tackle and beast. A special showing was arranged for senior British officers and the military attachés of all the embassies and legations in London. The MTC reported that,
Messrs Hornsby have now overcome the difficulties [and have] developed the chain track system commercially. The Committee are of the opinion that a light tractor built on a chain track would prove very valuable for the haulage of heavy artillery or howitzers.7
Ominously, the Royal Artillery representatives were
silent.
Lt Col Crompton had kept in touch with Holden and the committee, having resigned in 1905 to co-found and become secretary of the International Electrotechnical Commission. He now produced an improved steam-driven wheeled gun tractor in an attempt to overcome the weight problems of an earlier design which he had submitted to the committee. Light steel castings and forgings replaced much traditional cast iron, and the driving wheels were exceptionally large to spread load. The tractor underwent trials at Aldershot where it was outperformed by the Hornsby caterpillar. This experience undoubtedly influenced Crompton’s later thinking on motive power, and possibly traction, for armoured fighting vehicles.
The army took delivery of three more Hornsby tracklayers in July 1910. All were four-cylinder 50hp oil-engined machines, Nos. 35083–5. The War Office was getting rid of its steamers. Most of the heavy lorries and traction engines were sold out of the Service that year, to be replaced with internal combustion-engined vehicles.
The committee had also instructed Hornsbys to purpose-build a light tractor for gun haulage. The No. 3 machine on further improved tracks was duly handed over on 5 May 1910. Hornsby 35082 cost £1,200 plus £50 worth of spares. The 8-ton machine was driven uneventfully the 140 miles from Grantham to Aldershot. Cold starts for its 70bhp six-cylinder vertical oil engine were assisted by a petrol feed for the first ten minutes, at which point the vaporiser had been sufficiently heated by exhaust gases to allow a switch to paraffin. A less appealing alternative allowed for starts on paraffin providing a fitted blow torch was first played on the vaporiser for 30 minutes.
Trials began at once in the Long Valley at Aldershot with a 60-pdr gun and ammunition in tow. Holden attended with fellow artillerymen on the committee. The gun was hauled up 5ft banks with gradients of 1 in 3, and speed and crosscountry competitions were staged against a horsed gun. The committee concluded that the tractor’s work began where that of horses became impossible, but in short-distance haulage the machine’s top speed of 7.5mph was outpaced by a trotting horse team.
The Devil's Chariots Page 2
