That poisonous cloud that drifted across no man's land at Epe in April 1915 saw the birth of chemical warfare.

What's the story of gas in the trenches of the Great War and what can we find of it on the battlefields today?

If you stop the average person, of it on the battlefields today.

If you stop the average person in the street and ask them to name one weapon, one aspect of the Great War

that they were most familiar with that defined that war for them,

it would probably be poison gas.

Gas really came to stand for the nightmare of the war in the trenches.

Landscapes smashed to oblivion by shellfire,

the sun glinting on vicious, cruel barboire and thick poisonous clouds drenching that battlefield,

consuming the men within it. This is the nightmare of the First World War, a nightmare depicted in the writing, the literature and the poetry of the

Great War. Wilfred Owen, that everlasting voice for better or worse of the Great War,

himself had seen what gas attacks were like, how they would affect the troops that served alongside him in the second Manchester Regiment.

And in his poem, perhaps one of his most famous poems, Dulce de Coromest, this stanza really comes to stand, I think, for what most people perceive gas in the First World War to be like.

Gas!

Gas! Quick boys! An ecstasy of fumbling, fitting the clumsy helmets just in time.

But someone still was yelling out and stumbling and floundering like a man in fire or lime.

Dim through the misty panes and thick green light,

as under a green sea I saw him drowning.

And as the verses of that poem moves on,

he talks about white eyes writhing in the soldier's face.

His face like a devil's sick of sin and froth corrupted lungs.

And I'm sure that many generations of people studying the war poets, whether for history

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