Everybody damns the Tunneller; GHQ because he invariably has his job finished months before the rest of the Army are ready for the ‘Great Push’; Army troops because he invariably upsets all their preconceived notions as to the safety of trenches and dugouts; Divisional troops damn him because he is outside their sphere of influence; Brigade troops because he refuses to move when they do and because he knows by heart that part of the line to which they come as strangers; Brass hats because they dislike his underground habits; Regimental officers because he refuses to allow them to use his deep and snug dugouts; Subalterns because of his superior knowledge; Tommy because he is the direct cause of numerous extra fatigues and – alas that it should be so – because of his extra pay; and last and loudest, the Boche damn him because of his earnest and unceasing attempts at uplifting and converting them into surprised angels. It is also owing to his success in this noble work of the missionary that the Tunneller is highly respected by all branches of the forces.
[E Synton, 1918]
Undermining the positions of one’s enemy is one of the most ancient of martial activities. For almost 3000 years before 1914, and even after the invention of gunpowder and the inexorable development of artillery, it was a prime siege-breaking technique; indeed tunnelling is still employed across the world to the present day. The Great War, however, produced the greatest siege the world had ever seen, and its four years of stasis presented a conflict environment that perfectly favoured the skills of the military miner. By the end of May 1915 a continuous trench line, effectively an unbroken pair of fortress walls with no vulnerable flanks, stretched from the North Sea coast to the Swiss frontier. It was to grow into a huge network of defence-in-depth earthworks. With both sides equally well dug-in and deploying comparable troop numbers and armaments, neither was to prove strong enough to force a decisive breakthrough. Siege conditions demanded siege tactics: as the ground was everywhere mineable, the Western Front was a prime candidate for underground warfare.
By a curious twist of fate, military mining against British and Dominion troops began at Givenchy-lès-la Bassée, nearby the site of the new Tunnellers Memorial. On 21 December 1914 the Germans secretly dug shallow tunnels across No Man’s Land and exploded ten small but deadly mines beneath the primitive trenches of the Indian Sirhind Brigade. As the news spread up and down the line, alarm increased: how could this new and unexpected threat be countered? It couldn’t – adequately – for at that time the British had no military mining corps. Further German blows in the new year spurred the British to react with uncharacteristic alacrity.
By March 1915 the first Tunnelling Companies had been formed and were at work in Flanders. By the close of that year mine warfare was more or less continuous wherever opposing trench lines lay within mutual striking distance. It had already become a 24- hour a day, 365-day a year operation. The man shown in the photo to the right is from 172 Tunnelling Company, the first unit William Hackett joined before being relocated to 254 TC in November 1915.
By mid-1916 the British had around 25,000 trained tunnellers. Almost twice that number of ‘attached infantry’ worked permanently alongside them acting as beasts of burden, fetching and carrying the many essential elements of mining paraphernalia, pumping air and water and removing spoil – the earth produced by the digging of the tunnels.
Parts of the Western Front became labyrinths of underground workings. Those troops not directly involved in tunnelling (including attached infantry) were allowed to know little of the aims of a mining scheme simply because the gestation of such endeavours could be so long – well over a year for the Messines offensive of 7 June 1917 – and so arduous, that leakage of information might lead not only to the wastage of colossal effort and the ruination of a plan, but the loss of many lives in the most hideous of circumstances: entombment, drowning, gassing or obliteration in cramped and claustrophobic galleries beneath no man’s land. Close relationships between tunnellers and their attached infantry were formed.
The tunnelling war was a game of blindfold cat and mouse. The only way to detect one’s enemy underground was by listening. In every tunnelling company considerable numbers of specially-selected men were employed solely on this vital task. Using at first just the naked ear and subsequently sensitive technical devices, listening became a highly developed and efficient art. Installed at the end of their tiny gallery, a trained listener would take notes of the compass bearing and estimated distance of suspect sounds. Comparing the notes of several listeners allowed triangulation of a sound’s origin, and thus an indication as to the location of the enemy, the direction he was heading, and the speed at which he was working. The favoured British listening aid was the Geophone (below). Employing two sensors a listener was able to ascertain the direction of hostile activity by moving the sensors until sound levels appeared equal in both ears. A compass bearing was then taken. When gauging distance only, both earpieces were plugged into a single sensor; this was a skill only gained by experience.
By the end of 1916 the scale of mine warfare had expanded to such an extent that there were not enough listeners to man every post, and central listening stations were devised. Working electronically like a telephone exchange, the signals from up to 36 remote sensors (Tele-geophones and Seismomicrophones) could be distinguished and recorded by just two men.
Mines and Camouflets
The ultimate effect of an offensive mine, an underground explosion designed to destroy a specific surface target, and usually forming a crater, was dependent upon the quantity, type and quality of explosive used, the nature of the soil and subsoil in which it had been planted, and the depth of the charge. During 1916 one thousand five hundred mines were exploded on the British front, but many thousands of lesser defensive charges were also blown. Known as camouflets (derived from French mining terminology), these were small, controlled and localised underground blasts generally designed not to break the surface and form craters, but to destroy a strictly limited area of underground territory – and its occupants. Two basic techniques were employed. The first was to plant one’s camouflet in one’s own tunnel, a listening post, or in a small spur which was specially dug towards suspect enemy sounds. This was the preferred method in tough ground such as hard clay, or the resilient chalks of Picardy. The second method was more applicable in softer ground, especially in the sandy ridges and spurs of the Ypres (Ieper) Salient. Here, a ‘torpedo’ or ‘Cylinder’ was used. These were specially prefabricated self-contained explosive charges housed in a tube, designed specifically for this kind of warfare. Kept in a store at the rear of tunnel systems, at least one torpedo was always prepared for action, fully charged, primed with a detonator, and ready for instant use. Torpedoes were also used from shallow tunnels to destroy trenches and dugouts.
Heavier charges were also used to damage larger areas of underground territory, the purpose being to either destroy substantial sections of hostile tunnels and the occupants, or make the ground so shattered that it was difficult to work. These bigger blows often cratered the surface. The problem with this kind of attack was that one’s own tunnel systems could be equally seriously damaged. Such tactics were used only in extremis, when the hostile threat was acute. This, therefore, was defensive mining, devised and adapted to protect ones own web of tunnels from enemy action. It came to be the main occupation of tunnellers on both sides. Thus a private and secret war was gradually created beneath the battlefields. With improvements in listening and defensive practices, successful offensive attacks against surface targets became less and less frequent. Most mine warfare came to take the form of a clandestine and barbaric battle with tunneller fighting tunneller with camouflets. Hand-to-hand fighting was also not unknown.
Clay-kicking (also known as ‘working on the cross’) was a specialist method used in England for driving tunnels for sewer, road and railway works through clay-based geology. In late 1914 the technique was proposed to the army by the creator of the Tunnelling Companies, John Norton-Griffiths, a British engineering entrepreneur who at that time was employing clay-kickers on one of his company’s contracts: the refurbishment of Manchester’s main sewer. Norton-Griffiths persuaded the military that this technique – and his men – were perfect for the clays of Flanders. By February 1915, and as a result of continuing severe enemy mining action, the suggestion was at last taken up. The first batch of kickers – called “Moles’ by Norton-Griffiths – left Manchester on a Thursday; by the following Monday they were already working underground in France – at Givenchy.
In employing the power of the legs to work a specially shaped and finely sharpened spade known as a ‘grafting tool’, clay-kicking allowed a small tunnel to be driven quickly and with minimal effort. The tool was pushed rather than kicked into the working ‘face’ with the feet, each ‘spit’ of clay being then levered out by a prising movement. Progress was thus much faster than digging by hand. Most importantly, however, the technique was almost silent in its application. Digging with a pick or mattock demanded that the earth be struck, creating noise which could be heard by enemy listeners. The Germans never used clay-kicking as it was not a technique employed in civil engineering; indeed, it remained unknown to them for the entire war. German Pioniere thus continued to work with small – and noisy – mattocks. The contrast in digging techniques was a key factor in the ultimate Commonwealth dominance of the subterranean battleground in clay geology. A typical clay-kicking team consisted of a ‘kicker’, who worked at the face, a ‘bagger’, who filled sandbags with the ‘spoil’, the lumps of clay, and a ‘trammer’, who trammed the bags out of the gallery on a small, rubber-tyred trolley on rails; on the return journey this was employed to bring timber in. A clay-kicking team ‘grafted’ for six hours, the shift working on a rotational basis, with the men taking turns at each job. Such teams became close-knit units and stayed together as long as injury, sickness or fate allowed. They were also responsible for timbering the tunnel. Having cut out the rough shape with the grafting tool, a ‘push-pick’ was used to trim the clay to the perfect size to allow a timber ‘sett’ to be installed. A sett consisted of four pieces of wood : a sole for the floor, two side trees (also know as legs), and a cap. The sole went in first, the legs next, and finally the cap. Because of the need for silent working no nails or screws were used; the sole and cap timbers were sawn with small rebated ‘steps’; these located the two legs so that the geophysical pressure of the swelling clays was all that was required to hold the sett firmly in place. Progress was made one sett at a time – nine inches. To encourage drainage the tunnel was always built on a slight uphill gradient of between 1:100 and 1:50. It is likely that the five-man party of which William Hackett was a member were employing clay-kicking to drive their tunnel towards the German lines.
The standard and most simple shafts were built entirely in timber and conformed to centuries-old designs. Although adequate in firm and dry conditions, the varying geological nature of the Flanders battlefields demanded new techniques to cope with the serious problem of bad ground, particularly the layer of quicksand known as the Kemmel Sands, an integral component of the geological make up of all the ridges around Ieper. For the Germans, occupying almost all the most advantageous positions on the ridge tops, this stratum was a serious headache. Tunnelling in the dry strata above the Kemmel Sands was simple, swift and easy, but sinking a shaft through the schwimmsands, as they were known (the British called them running sands), to reach the dry and firm clay geology beneath, was found to be unfeasible: the constantly shifting ground made timber structures almost impossible both to stabilise and waterproof. The sands, which were trapped between the dry stratum above and impervious clay beneath, were also under great geophysical pressure, and often ‘fountained’ when pierced. Believing that the British faced the same insoluble engineering problem, the Pioniere made few efforts to break through the schwimmsands until the spring of 1916.
What the Germans had failed to realise was that their enemy had conquered the geology by using cylindrical steel shafts known as ‘tubbing’. Tubbing arrived in sections which were bolted together to form a watertight tube. These were sunk through the wet sands (see illustration above) to the dry clay beneath either by the gravitational action of their own weight, or by jacks. Once the steel had reached the dry clay it was again safe to continue the work in timber. The system was quick, simple, strong, stable and waterproof – and allowed the British to delve deep into the Flanders clay in many places where their enemy believed it to be impossible. Critically, the British first used steel shafts as early as May 1915 – almost a full year before the Pioniere. By the spring of 1916 when the Germans were forced to sink watertight shafts in steel (and concrete) because the British had started blowing deep mines, the subterranean war was effectively lost to them. In this ‘year of German ignorance’ the Tunnellers had been able to secretly drive many deep galleries and plant the greatest mines in the history of warfare.
Underground, tunnellers faced many a threat: entombment, obliteration, health problems brought on by the workload, working environment and poor air quality; there was even the risk of drowning. But the biggest killer was actually gas poisoning; not the designed toxic vapour variety used in cloud and shell form by troops on the surface, but carbon monoxide (CO), an invisible, odourless and tasteless substance that was naturally produced by every explosive action – even the firing of a simple rifle bullet. In mines that broke the surface, or in the case of a shell burst, carbon monoxide quickly dissipated into the atmosphere; after an underground explosion, however, it is trapped – in the geology and in the tunnels.
Carbon Mnoxide displaces oxygen in the blood. The process is cumulative, resulting in body tissues being gradually starved of oxygen and energy. Death, when it comes, is painless, gentle and insidious, but in the tunnels it was a terrifying prospect. With lowlevel concentrations men could be entirely unaware of its presence, allowing them to penetrate deep into a system before being affected. As little as 0.1 percent CO in air was dangerous, and it was found that a man at rest in an atmosphere of 0.15 percent CO would be affected after two hours, reducing to about forty minutes if working strenuously. A concentration of 0.2 percent caused loss of consciousness in around twenty-five minutes, and 0.3 percent in ten to fifteen minutes. If the gas was present in large quantities, a tunneller could be unconscious in a matter of moments – with little warning. The early symptoms were giddiness, shortness of breath and palpitations, with confusion following. There was then a loss of power in the limbs. When this stage was reached a little exertion would induce loss of consciousness.
In extensive mine systems galleries were fitted with regulator doors, effectively producing a series of airlocks. The spread of gas could therefore be isolated so rescue work was simplified and tunnellers in unaffected areas could continue to operate. For rescue purposes several forms of self-contained breathing apparatus were used. However, it was first essential to find out whether the air below ground was ‘gassy’ or not. To achieve this Tunnellers employed the traditional practice of using canaries and mice. As both creatures have a much higher metabolic rate than humans, they are therefore more quickly affected by CO gas. Mice were superceded by canaries as signallers for their curling up in a corner of the cage was not sufficiently evident; a canary, however, was prone to fall off its perch, a more obvious indication of risk. The British eventually organised a highly developed system of rescue. In mining sectors no shaft was further than 200 metres from a station. Proto-men (named after the breathing kit they employed) were highly trained, hand picked men, selected for experience and coolness under pressure. Two men were on duty at all times. Apart from the rescue gear and oxygen reviving equipment each station contained: Ten electric miners lamps, six canaries (or mice) with four mobile cages and two living cages, one saw, one hand axe, three life lines, two mine stretchers, one trench stretcher, one Primus stove, two tins of café au lait, six hot water bottles, six blankets.
When in spring 1917 the war became more mobile with the grand sequence of offensives of the Battles of Arras, Messines and Passchendaele, there was no longer a place for a tactic that depended upon total stasis for its employment. Offensive and defensive military mining largely ceased. Underground work continued unabated, however, with the Tunnellers concentrating on mined ‘deep dugouts’ for troop accommodation.
Kila mtu anamlaani Tunneler; GHQ kwa sababu yeye daima ana kazi yake kumaliza miezi kabla ya mapumziko ya Jeshi ni tayari kwa ajili ya 'Great Push'; Jeshi askari kwa sababu yeye daima upsets dhana zao zote zilizopangwa mapema kama kwa usalama wa migodi na dugouts; Vikosi vikosi kumlaani kwa sababu yeye ni moja kwa moja sababu ya uchovu wengi na - alas! - kwamba ni lazima kuwa hivyo - kwa sababu ya malipo yake ya ziada; na mwisho na loudest, damn Boche kwa sababu ya jaribio lake kubwa na unchanging ya kuondoa na kugeuza yao katika malaika. Ni kwa sababu ya mafanikio yake katika kazi hii ya kifalme ya mishonari kwamba Tunneler ni kuheshimiwa sana na matawi yote ya vikosi. [Eton Synton, 1918] Kudhoofisha nafasi za adui ni moja ya shughuli za kale zaidi za kijeshi. Kwa karibu miaka 3000 kabla ya 1914, na hata baada ya uvumbuzi wa risasi na maendeleo ya makombora, ilikuwa mbinu ya kwanza ya kuvunja kuzingirwa; kwa kweli kuchimba handaki bado hutumiwa ulimwenguni kote hadi leo. Vita Kuu ya Ulimwengu ya Kwanza ilisababisha kuzingirwa kwa dunia kwa miaka minne, na mazingira ya mapigano yalipendelea sana ustadi wa wachimbaji wa madini. Kufikia mwishoni mwa Mei 1915, mstari wa matundu uliendelea, kwa ufanisi, ni jozi ya kuta za ngome zisizo na mipaka, ambazo hazikuwa na pande zilizoathirika, zilizong'aa kutoka pwani ya Bahari ya Kaskazini hadi mpaka wa Uswisi. Ilikuwa kukua katika mtandao mkubwa wa ulinzi-katika-kuzama earthworks. Kwa kuwa pande zote mbili zilikuwa zimejificha vizuri na zilikuwa na idadi sawa ya askari na silaha, hakuna hata moja iliyokuwa na nguvu ya kutosha kulazimisha uvamizi wa kuvutia. Hali za kuzingirwa zilihitaji mbinu za kuzingirwa: kwa kuwa ardhi ilikuwa mahali popote ikiweza kuchimbwa, Sehemu ya Magharibi ilikuwa nafasi bora ya kupigana vita vya chini ya ardhi. Kwa twist ya ajabu ya hatima, uchimbaji wa kijeshi dhidi ya vikosi vya Uingereza na Dominion ulianza huko Givenchy-lès-la-Bassee, karibu na tovuti ya Tunnellers Memorial mpya. Mnamo Desemba 21, 1914, Wajerumani walichimba kwa siri mifereji ya chini ya ardhi katika eneo la No Man's Land na kulipua mabomu kumi madogo lakini yenye kuua chini ya mapango ya kikosi cha Sirhind cha India. Kadiri habari zilivyoenea, ndivyo wasiwasi ulivyoongezeka: tishio hili jipya na lisilotazamiwa lingeweza kushughulikiwaje? Haingeweza <unk> kwa usahihi <unk> kwa wakati huo Waingereza hawakuwa na jeshi la uchimbaji madini. Mashambulizi zaidi ya Ujerumani katika mwaka mpya yaliwachochea Waingereza kujibu kwa haraka isiyo ya kawaida. Kufikia Machi 1915, makampuni ya kwanza ya kuchimba handaki yalikuwa yameanzishwa na yalikuwa yakifanya kazi katika Flanders. Kufikia mwishoni mwa mwaka huo, mapigano ya mabomu ya ardhini yalikuwa yakipiganwa kwa kuendelea karibu kila mahali ambapo mipaka ya mapigano ya wapiganaji ilikuwa katika umbali wa kushambulia. Kwa sasa, kazi hiyo inafanywa kwa masaa 24 kwa siku, siku 365 kwa mwaka. "Mtu aliyeonyeshwa kwenye picha ya kulia ni kutoka kwa ""172 Tunneling Company,"" kitengo cha kwanza ambacho William Hackett alijiunga nacho kabla ya kuhamishwa kwenda 254 TC mnamo Novemba 1915."" Kufikia katikati ya mwaka wa 1916, Waingereza walikuwa na wafanyakazi 25,000 waliozoezwa kuchimba handaki. Karibu mara mbili ya idadi hiyo ya 'wanajeshi wa miguu waliohusishwa' walifanya kazi kwa kudumu pamoja nao wakitenda kama wanyama wa kubeba mzigo, wakileta na kubeba vitu vingi muhimu vya madini, kupumua hewa na maji na kuondoa nyara - ardhi iliyotokezwa na kuchimba handaki. Sehemu fulani za Mstari wa Magharibi zikawa labyrinths za kazi za chini ya ardhi. Wanajeshi ambao hawakujihusisha moja kwa moja na kuchimba handaki (ikiwa ni pamoja na wanajeshi wa miguu waliohusishwa) waliruhusiwa kujua kidogo juu ya malengo ya mpango wa uchimbaji madini kwa sababu tu ujauzito wa juhudi kama hizo unaweza kuwa mrefu sana - zaidi ya mwaka mmoja kwa mashambulizi ya Messina ya Juni 7, 1917 - na ngumu sana, kwamba kuvuja kwa habari kunaweza kusababisha sio tu kupoteza juhudi kubwa na uharibifu wa mpango, lakini hasara ya maisha mengi katika hali mbaya zaidi: kuzikwa, kuzama, kuharibiwa gesi au kuharibiwa. Uhusiano wa karibu kati ya wachimba-migodi na wanajeshi wao waliohusika ulianzishwa. Vita vya kuchimba handaki vilikuwa mchezo wa paka na panya wenye macho yaliyofungwa. Njia pekee ya kugundua adui ya mtu chini ya ardhi ilikuwa kwa kusikiliza. Katika kila kampuni ya kuchimba handaki idadi kubwa ya watu waliochaguliwa kwa pekee walitumika tu katika kazi hii muhimu. Kwa kutumia sikio la kawaida tu mwanzoni na baadaye vifaa vya kiufundi vyenye utambuzi, kusikiliza kukawa sanaa iliyoendelea sana na yenye matokeo. Msikilizaji aliyezoezwa, aliyekuwa amewekwa mwishoni mwa chumba chao kidogo, angeandika mwelekeo wa dira na umbali uliokadiriwa wa sauti zisizofaa. Kulinganisha maelezo ya wasikilizaji kadhaa kuliruhusu utatu wa asili ya sauti, na hivyo ishara ya eneo la adui, mwelekeo alikuwa akienda, na kasi ambayo alikuwa akifanya kazi. Kifaa cha kusikia kilichopendwa sana na Waingereza kilikuwa Geophone (chini). Kwa kutumia sensorer mbili msikilizaji aliweza kujua mwelekeo wa shughuli za uhasama kwa kuhamisha sensorer hadi viwango vya sauti vilipoonekana sawa katika masikio yote mawili. Kisha mwelekeo wa dira ukachukuliwa. Wakati wa kupima umbali tu, vichwa vyote viwili vilikuwa vimeunganishwa kwenye sensorer moja; hii ilikuwa ustadi uliopatikana tu kwa uzoefu. Kufikia mwishoni mwa mwaka 1916, kiwango cha mapigano ya mabomu ya ardhini kilikuwa kimepanuka sana hivi kwamba hakukuwa na wasikilizaji wa kutosha kwa kila ngome, na vituo vya kusikiliza vya kati vilitengenezwa. Kwa kutumia vifaa vya elektroniki kama vile kituo cha simu, ishara kutoka kwa sensorer 36 za mbali (Tele-geophones na Seismomicrophones) zingeweza kutambuliwa na kurekodiwa na wanaume wawili tu. "Mini ya ""mashambulizi"" ni shambulio la chini ya ardhi lililokusudiwa kuharibu lengo fulani la uso, na kwa kawaida kufanyiza shimo, na lilitegemea kiasi, aina na ubora wa mlipuko uliotumiwa, asili ya udongo na chini ya ardhi ambayo ilikuwa imepandwa, na kina cha risasi." Katika mwaka wa 1916 mabomu ya ardhini elfu moja na mia tano yalitumiwa katika mapigano ya Uingereza, lakini maelfu mengi ya mabomu madogo ya ulinzi yalitumiwa pia. Kama vile camouflets (kutokana na Kifaransa madini terminolojia), hizi walikuwa ndogo, kudhibitiwa na eneo chini ya ardhi milipuko kwa ujumla iliyoundwa si kuvunja uso na fomu craters, lakini kuharibu eneo la kikamilifu mdogo wa chini ya ardhi eneo <unk> na wakazi wake. Mbinu mbili za msingi zilitumiwa. Ya kwanza ilikuwa kupanda camouflet ya mtu katika handaki la mtu mwenyewe, kituo cha kusikiliza, au katika msukumo mdogo ambao ulichimbwa maalum kuelekea sauti za adui zinazotiliwa shaka. Njia hiyo ilipendekezwa katika ardhi ngumu kama vile udongo mgumu, au chokaa zenye nguvu za Picardy. Njia ya pili ilitumika zaidi katika ardhi laini, hasa katika vilele vya mchanga na miamba ya Ypres (Yeper) Salient. Hapa, <unk>torpedo<unk> au <unk>Cylinder<unk> ilitumiwa. Hizi zilikuwa mizigo ya kulipuka iliyojengwa kando-kando iliyowekwa ndani ya bomba, iliyoundwa hasa kwa ajili ya aina hii ya vita. Torpedo moja au zaidi ilifanywa kuwa tayari kwa ajili ya vitendo, ikiwa imejaa kabisa, ikiwa imewekwa na kifaa cha kusababisha mlipuko, na ikiwa tayari kwa matumizi ya papo hapo. Torpedo zilitumiwa pia kutoka katika mifereji midogo ili kuharibu mitaro na vibanda. Mashambulizi makubwa zaidi yalitumiwa kuharibu maeneo makubwa ya chini ya ardhi, kwa kusudi la kuharibu sehemu kubwa za vichuguu vya adui na wakazi, au kufanya ardhi iharibike sana hivi kwamba ilikuwa vigumu kufanya kazi. Mara nyingi mapigo hayo makubwa yalifanya miamba juu ya uso wa ardhi. Tatizo la aina hii ya shambulio lilikuwa kwamba mifumo ya handaki ya mtu mwenyewe ingeweza kuharibiwa vibaya vilevile. Mbinu hizo zilitumiwa tu katika hali ya mwisho, wakati tisho la adui lilipokuwa kali. Kwa hiyo, hii ilikuwa uchimbaji wa madini ya kujilinda, uliobuniwa na kurekebishwa ili kulinda mtandao wa vichuguu vya mtu mwenyewe kutokana na hatua ya adui. Ilikuwa kazi kuu ya wachimbaji wa handaki upande wote. Hivyo, hatua kwa hatua vita vya faragha na vya siri vilianzishwa chini ya maeneo ya vita. Kwa sababu ya maendeleo katika mazoezi ya kusikiliza na ya kujilinda, mashambulizi yenye mafanikio dhidi ya malengo ya juu ya ardhi yakawa ya mara chache na mara chache zaidi. Vita vya mabomu ya ardhini vilikuwa vita vya siri na vya kikatili, na watu waliofanya kazi katika migodi walipigana na watu waliofanya kazi katika migodi kwa kutumia silaha za kufunika nyuso. Mapigano ya mikono pia hayakuwa ya kawaida. Clay-kicking (pia inajulikana kama <unk> kufanya kazi juu ya msalaba <unk>) ilikuwa mbinu maalum kutumika katika Uingereza kwa ajili ya kuendesha handaki kwa ajili ya mfereji wa maji machafu, barabara na reli kazi kupitia geology msingi udongo. "Mwanzoni mwa mwaka wa 1914, mtengenezaji wa kampuni ya ""Tunnel"" John Norton Griffiths, ambaye alikuwa mjasiriamali wa Uingereza, alianzisha mradi wa ujenzi wa mfereji wa maji machafu huko Manchester." Norton-Griffiths aliwashawishi wanajeshi kwamba mbinu hii - na watu wake - walikuwa kamili kwa ajili ya udongo wa Flanders. Kufikia Februari 1915, na kama matokeo ya kuendelea na shughuli kali za madini ya adui, pendekezo hilo lilichukuliwa hatimaye. Kundi la kwanza la kickers - aitwaye "Moles" na Norton-Griffiths - kushoto Manchester juu ya Alhamisi; na Jumatatu iliyofuata walikuwa tayari kufanya kazi chini ya ardhi katika Ufaransa - katika Givenchy. Kwa kutumia nguvu za miguu ili kuendesha jembe lenye umbo la pekee na lililopigwa kwa uangalifu linalojulikana kama "chombo cha kupandikiza", kupiga-piga udongo kuliruhusu handaki dogo lichimbwe haraka na kwa jitihada ndogo. Kifaa hicho kilisukumwa badala ya kupigwa kwa miguu kwenye "uso" wa kazi, kila "mchomo" wa udongo ukitolewa kwa harakati ya kukandamiza. Hivyo, maendeleo yalikuwa ya haraka zaidi kuliko kuchimba kwa mkono. Hata hivyo, jambo la maana zaidi ni kwamba mbinu hiyo haikutumiwa. Kuchimba kwa kutumia mkuki au mkuki kulihitaji kwamba ardhi ipigwe, ikitokeza kelele ambayo ingeweza kusikilizwa na wasikilizaji wa adui. Wajerumani hawakutumia mbinu ya kupiga matope kwa sababu haikuwa mbinu iliyotumiwa katika uhandisi wa ujenzi; kwa kweli, ilibaki haijulikani kwao kwa vita vyote. Kwa hiyo, Pioniere wa Ujerumani waliendelea kufanya kazi kwa kutumia matoko madogo na yenye kelele. Tofauti katika mbinu za kuchimba ilikuwa sababu muhimu katika utawala wa mwisho wa Jumuiya ya Madola wa uwanja wa vita wa chini ya ardhi katika jiolojia ya udongo. Kikundi cha kawaida cha kupiga matope kilikuwa na <unk>kicker<unk>, ambaye alifanya kazi kwenye uso, <unk>bagger<unk>, ambaye alijaza mifuko ya mchanga na <unk>spoil<unk>, vipande vya udongo, na <unk>trammer<unk>, ambaye alisafirisha mifuko nje ya gallery kwenye troli ndogo ya mpira kwenye reli; katika safari ya kurudi hii ilitumika kuleta mbao. Kikundi cha wachimba-matope "kilichimba" kwa saa sita, zamu ikifanya kazi kwa mzunguko, wanaume wakibadilishana katika kila kazi. Timu hizo zikawa vikundi vilivyounganishwa kwa ukaribu na kukaa pamoja kwa muda mrefu kama jeraha, ugonjwa au hatima iliruhusu. Pia walikuwa na daraka la kuunganisha mbao kwenye handaki hilo. Baada ya kukata sura mbaya kwa chombo cha kupandikiza, <unk>push-pick<unk> ilitumiwa kukata udongo kwa ukubwa kamili ili kuruhusu <unk>set<unk> ya mbao kuwekwa. Seti ilijumuisha vipande vinne vya mbao: kiatu cha sakafu, miti miwili ya upande (pia inajulikana kama miguu), na kofia. Kwanza kiatu kiliingia, kisha miguu, na hatimaye kofia. Kwa sababu ya haja ya kufanya kazi kimya hakuna misumari au screws zilitumiwa; tufu na kifuniko mbao walikuwa sawed na ndogo rebated 'hatua'; hizi ziko miguu miwili hivyo kwamba shinikizo geophysical ya swelling udongo ilikuwa yote ambayo ilihitajika kushikilia kuweka imara katika mahali. Maendeleo yalifanywa moja kuweka kwa wakati <unk> inchi tisa. Ili kuchochea mifereji ya maji, kila mara handaki hilo lilijengwa kwa mwinuko mdogo wa kati ya 1:50 na 1:50 mwinuko. Inawezekana kwamba kikundi cha watu watano ambacho William Hackett alikuwa mshiriki kilikuwa kikitumia matope-kicking kuendesha handaki lao kuelekea mistari ya Ujerumani. Vituo vya kawaida na vya rahisi zaidi vilijengwa kabisa kwa mbao na vilifuata miundo ya karne nyingi zilizopita. Ingawa hali ya vita ya Flanders ilikuwa nzuri katika hali ngumu na kavu, hali tofauti ya kijiolojia ilihitaji mbinu mpya za kukabiliana na tatizo kubwa la ardhi mbaya, hasa safu ya mchanga unaoelea unaojulikana kama mchanga wa Kemmel, sehemu muhimu ya muundo wa kijiolojia wa vilima vyote karibu na Ieper. Kwa Wajerumani, waliokuwa karibu na maeneo yote yenye faida zaidi kwenye vilele vya milima, safu hiyo ilikuwa tatizo kubwa. Kufungua handaki katika matope ya juu ya mchanga wa Kimmel ilikuwa rahisi, lakini kuzama shaft kupitia mchanga wa swimm, kama walivyojulikana (Wangereza waliwaita mchanga wa kukimbia), kufikia jiolojia kavu na thabiti ya udongo chini, iligunduliwa kuwa haiwezekani: ardhi inayobadilika daima ilifanya miundo ya mbao iwe karibu haiwezekani kuimarisha na kuzuia maji. Mchanga, ambao ulikuwa umekamatwa kati ya tabaka kavu juu na udongo usioweza kupenya chini, pia ulikuwa chini ya shinikizo kubwa la kijiografia, na mara nyingi "ulitoka" wakati wa kupasuka. "Kwa kuwa Pioneer ilidhani kwamba Uingereza ilikuwa inakabiliwa na tatizo hilo, ilijitahidi sana kuvunja mchanga huo hadi mwaka wa 1916.""" Kile ambacho Wajerumani walishindwa kutambua ni kwamba adui yao alikuwa ameshinda jiolojia kwa kutumia shafts za chuma za silinda zinazojulikana kama <unk>tubbing<unk>. Tubbing ilifika katika sehemu ambazo zilikuwa zimeunganishwa pamoja ili kufanyiza bomba lisiloweza kuingizwa maji. Vitu hivyo vilitupwa ndani ya mchanga wenye unyevunyevu (tazama picha iliyo juu) na kuingia kwenye udongo ulio kavu chini ya mchanga huo, ama kwa nguvu za uvutano wa uzito wao wenyewe, ama kwa kutumia vijiti. Mara tu chuma kilipofika kwenye udongo kavu ilikuwa salama tena kuendelea na kazi katika mbao. Mfumo huo ulikuwa wa haraka, rahisi, wenye nguvu, thabiti na usiovumilika na uliwaruhusu Waingereza kuchimba ndani ya udongo wa Flanders katika maeneo mengi ambapo adui yao aliamini kuwa haiwezekani. "Mashine ya chuma ya Uingereza ilitumiwa kwa mara ya kwanza mnamo Mei 1915 - karibu mwaka mzima kabla ya ""Pioneer.""" Mnamo mwaka wa 1916, wakati Wajerumani walipowalazimika kuzama shimo la chuma (na saruji) kwa sababu Waingereza walikuwa wameanza kulipua mabomu ya ardhini, vita vya chini ya ardhi vilikuwa vimepotea. Katika "mwaka huu wa ujinga wa Ujerumani" Tunnellers walikuwa na uwezo wa siri kuendesha makumbusho mengi ya kina na kuweka mabomu makubwa zaidi katika historia ya vita. Katika chini ya ardhi, wachimbaji wa handaki walikabili hatari nyingi: kuzikwa, kuharibiwa, matatizo ya afya yaliyosababishwa na mzigo wa kazi, mazingira ya kazi na hali mbaya ya hewa; kulikuwa hata hatari ya kuzama. Lakini muuaji mkubwa zaidi alikuwa sumu ya gesi; si aina ya mvuke wa sumu iliyobuniwa kutumika katika wingu na umbo la shell na askari juu ya uso, lakini kaboni monoksidi (CO), dutu isiyoonekana, isiyo na harufu na isiyo na ladha ambayo ilitengenezwa kwa asili na kila hatua ya mlipuko - hata risasi ya bunduki rahisi. Katika migodi ambayo kuvunja uso, au katika kesi ya shell kulipuka, kaboni monoksidi haraka dissipated katika anga; baada ya mlipuko wa chini ya ardhi, hata hivyo, ni kukamatwa <unk> katika jiolojia na katika mifereji. Kaboni-monoxide huondoa oksijeni katika damu. Utaratibu huo huongezeka, na kwa sababu hiyo tishu za mwili hupoteza oksijeni na nishati hatua kwa hatua. Kifo, kinapokuja, hakina maumivu, ni laini na chenye hila, lakini katika matundu hayo kilikuwa jambo lenye kuogopesha. Kwa viwango vya chini, watu wanaweza kuwa hawajui kabisa juu ya uwepo wake, na hivyo kuweza kupenya ndani ya mfumo kabla ya kuathiriwa. Hata asilimia 0.1 ya CO katika hewa ilikuwa hatari, na iligunduliwa kwamba mtu aliyepumzika katika anga ya asilimia 0.15 ya CO angeharibiwa baada ya saa mbili, akipunguza hadi dakika 40 ikiwa anafanya kazi kwa bidii. Kiwango cha 0.2%, kilisababisha kupoteza fahamu baada ya dakika 25 na 0.3% baada ya dakika 10-15. Ikiwa gesi hiyo ilikuwapo kwa wingi, mchimba-mbinu angeweza kupoteza fahamu kwa muda mfupi - bila kuonya. Dalili za mapema zilikuwa kizunguzungu, kukosa pumzi na kupiga moyo, na kuchanganyikiwa kulifuata. Kisha akaanza kupoteza nguvu katika viungo vyake. Hatua hiyo ilipofikiwa, jitihada ndogo-ndogo zingeweza kumfanya apoteze fahamu. Katika mifumo mikubwa ya migodi, vichuguu vilitengenezwa kwa milango ya kudhibiti, kwa ufanisi kutokeza mfululizo wa airlocks. Kwa hiyo kuenea kwa gesi kulifanywa kuwa peke yake ili kazi ya uokoaji iwe rahisi na tunnellers katika maeneo yasiyoathiriwa inaweza kuendelea kufanya kazi. Kwa madhumuni ya uokoaji aina kadhaa za vifaa vya kupumua vilivyojitegemea vilitumiwa. Hata hivyo, ilikuwa muhimu kwanza kujua kama hewa chini ya ardhi ilikuwa "gasi" au la. Ili kufanya hivyo, wafanya-barabara walitumia mbinu ya kitamaduni ya kutumia ndege aina ya canary na panya. Kwa kuwa wanyama wana kiwango cha juu zaidi cha kimetaboliki kuliko wanadamu, wanaathiriwa haraka na gesi ya CO2. Panya walikuwa badala ya canaries kama signalers kwa curling yao juu katika kona ya ngome haikuwa wazi kutosha; canary, hata hivyo, alikuwa na mwelekeo wa kuanguka nje ya perch yake, dalili dhahiri zaidi ya hatari. Hatimaye Waingereza walianzisha mfumo wa kuokoa walioendelea sana. Katika sekta ya madini hakuna shaft ilikuwa zaidi ya mita 200 kutoka kituo. Wanaume wa zamani (waliopewa jina kutokana na kifaa cha kupumua walichotumia) walikuwa wanaume waliozoezwa sana, waliochaguliwa kwa mikono, waliochaguliwa kwa uzoefu na baridi chini ya shinikizo. Wanaume wawili walikuwa wakifanya kazi wakati wote. Mbali na vifaa vya kuokoa na vifaa vya kuokoa oksijeni, kila kituo kilikuwa na: taa kumi za umeme za wachimbaji, panya sita (au panya) na ngome nne za kusafiri na ngome mbili za kuishi, jembe moja, shoka moja, mistari mitatu ya maisha, magurudumu mawili ya mgodi, magurudumu moja ya mtaro, jiko moja la Primus, makopo mawili ya kahawa au maziwa, chupa sita za maji moto, na blanketi sita. Wakati wa majira ya kuchipua ya 1917, vita vilipokuwa vikipita kwa kasi zaidi, kwa sababu ya mapigano ya Arras, Messines na Passchendaele, hakukuwa na nafasi ya mbinu ya kupigana ambayo ilitegemea kusimamishwa kabisa kwa matumizi yake. Uchimbaji wa madini ya kijeshi ya kushambulia na ya kujilinda ulikoma kwa kiasi kikubwa. Hata hivyo, kazi ya chini ya ardhi iliendelea bila kupumzika, na Wafanyabiashara wa Mifereji wakazingatia "maeneo ya chini ya ardhi" yaliyochimbwa kwa ajili ya makazi ya askari.