'My parents didn't want to hear of life on the front'
Private Norman Demuth's parents had no idea what the war was like.
In 1916, as the Battle of the Somme raged, a soldier at home on leave found it hard to talk to his parents. To his surprise, Norman Demuth, a private in the London Regiment, discovered his mother and father had little interest in what their son's daily life on the Western Front was like.
"They didn't know, how could they?" he said in an account now held in the archives of the UK's Imperial War Museum (IWM).
"They knew that people came back on leave covered with mud and lice, but they had no idea of what kind of danger we were in. I think they felt the war was one continual sort of cavalry charge."
In fact, there hadn't been a cavalry charge, at least on the Western Front, for almost two years.
After the Battle of the Aisne had ended in stalemate in September 1914, the two sides had dug huge networks of trenches that would eventually extend for hundreds of miles across Belgium and northern France and settled into a grinding war of attrition.
Trench warfare became a feature of other fronts, including Gallipoli, Salonika and the Italian front.
Life in the trenches was a part of the wartime experience of millions of combatants, but as Demuth discovered, most people at home had little concept of what this entailed.
But while popular depictions of World War I like 'Blackadder Goes Forth' give the impression that soldiers lived full-time in the trenches, in fact most troops were rotated in and out on a regular basis.
The British army, for example, used a rotation system, which meant the average 'Tommy' spent around 15pc of his time in the front-line trenches, another 40pc in support and reserve trenches further back and the remaining 45pc out of the trenches behind the lines, receiving training or medical care or resting.
The support areas were linked to the front line by service trenches, and dug-outs built into the side of trench walls provided a measure of shelter and somewhere to sleep.
Trenches were constructed in zig-zag routes rather than a straight line, so that if an enemy soldier jumped down into one during an attack he couldn't aim a gun along the trench and kill every man in it.
But however sophisticated the trench network, a stint in the trenches – essentially holes in the ground dug more than 2.3 metres deep so soldiers could walk in them without having to stoop – was a grim prospect. The trenches were infested with lice and fleas.
Lice caused "trench fever", the symptoms of which included headaches, high temperatures and muscle pains.
The unsanitary conditions and bodies lying around after an attack attracted rats in their droves. In his autobiography 'Goodbye to All That', the writer and Great War veteran Robert Graves describes a new officer sleeping on a camp bed in a dug-out waking to find "two rats on his blanket tussling for the possession of a severed hand".
When it rained, the trenches often rapidly filled with water and everything turned to mud.
Trench floors were lined with wooden "duckboards" and hand-powered pumps were introduced to pump out the water, but neither measure was totally effective.
Standing around in the cold and wet caused the fungal infection "trench foot", which made it hard for the afflicted soldier to stand and could lead to gangrene if not treated.
It affected some 30,000 British troops in 1915, but an order for soldiers to change their socks three times a day and foot inspections by officers had largely solved the problem by the following year.
Between attacks, life in the trenches was a mixture of boring routine with moments of danger or terror.
At "stand to" before dawn, soldiers would fire their weapons at the enemy in a daily ritual known as the "morning hate".
The rest of the day was taken up with trench maintenance, chores and a chance to catch some sleep or write home. There was another "stand to" at dusk before parties were sent on perilous sorties into no man's land under the cover of darkness.
Initially, British troops in the trenches had to make do with cold rations, though hot meals were provided from late 1915.
This often meant warming canned "bully beef" over a tiny stove, but the food was at least filling and usually plentiful – soldiers regularly complained of being "bunged up" – though the menu was repetitive.
But if you were unlucky enough to be on duty in a front-line trench during one of the major offensives, this routine could be shattered by the order to "go over the top" and attack the enemy across no man's land, a foolhardy strategy that often resulted in massive casualties.
For example, nearly 20,000 British troops were killed, including Irish soldiers from the 36th (Ulster) Division and the Royal Dublin Fusiliers, on July 1, 1916, the first day of the Battle of the Somme.
In another account in the IWM archive, German medical officer Stefan Westmann described an Allied bombardment on the Somme that lasted seven days: "Soldiers in the bunkers became hysterical – they wanted to run out... even the rats became hysterical and came into our flimsy shelters to seek refuge from this terrific artillery fire."
Yet the troop rotation system and the trenches' clever design and other safety measures meant that in the British army, almost 90pc of the men who served in the trenches survived.
But when soldiers like Private Demuth went on leave or came home after the armistice, they found that civilians had little or no idea of "the strain of sitting in a trench and waiting for something to drop on one's head".
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