The old Lie: Dulce et Decorum est

This morning I popped into Aberdeen University's Kings Museum to see Elements, their new exhibition, which explores the elements that make up our world using objects form the University's scientific collections. I was particularly struck by this gruesome gas mask from the First World War, which represents the element chlorine.
The first use of poisonous gas was by the Germans at Langemarck in the Ypres Salient in Flanders where there were large concentrations of French, British and Canadian troops. On the 11th April 1915, the Germans opened the valves on 6,000 gas cylinders releasing 160 tons of chlorine into a light breeze. The gas cloud flooded the trenches of the unsuspecting French Colonials and Territorials. In desperate panic they broke and fled to the rear causing a four-mile gap in the line. This violent evasive exercise, and their running along with the drift of the cloud, greatly exacerbated the effect of the gas. Whilst those who cowered, or collapsed, into the bottom of the trenches were engulfed with increasing concentrations of the gas as it settled.
Fearful of further gas attacks, the British rapidly developed the 'Hypo Helmet' a wool flannel hood entirely soaked in sodium hyposulphite to neutralize chlorine. The hood with a mica window fitted over the head to the shoulders. By May 1915, it was being distributed to the British Expeditionary Force at a rate of 1,000 per Division.
Cautious of further poisons that the Germans might deploy, such as phosgene and hydrogen cyanide, scientists sought out other solutions that could be used to impregnate the Hypo Helmet against these gases. The outcome was the cotton fabric 'P Helmet', impregnated with sodium phenate as well as sodium hyposulphite , and effective against chlorine, phosgene and hydrogen cyanide. It had two 'goggle type' glass eyepieces and a one-way breathing tube held in the mouth for expelling the used carbon-dioxide rich air. By November 1915, every British soldier in the BEF had a personal 'P Helmet'.

The full horror of a gas attack is well described by Wilfred Owen in Dulce et Decorum Est.

DULCE ET DECORUM EST

Bent double, like old beggars under sacks,
Knock-kneed, coughing like hags, we cursed through sludge,
Till on the haunting flares we turned our backs
And towards our distant rest began to trudge.
Men marched asleep. Many had lost their boots
But limped on, blood-shod. All went lame; all blind;
Drunk with fatigue; deaf even to the hoots
Of tired, outstripped Five-Nines that dropped behind.
Gas! Gas! Quick, boys! - An ecstasy of fumbling,
Fitting the clumsy helmets just in time;
But someone still was yelling out and stumbling,
And flound'ring 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.
In all my dreams, before my helpless sight,
He plunges at me, guttering, choking, drowning.
If in some smothering dreams you too could pace
Behind the wagon that we flung him in,
And watch the white eyes writhing in his face,
His hanging face, like a devil's sick of sin;
If you could hear, at every jolt, the blood
Come gargling from the froth-corrupted lungs,
Obscene as cancer, bitter as the cud
Of vile, incurable sores on innocent tongues,
My friend, you would not tell with such high zest
To children ardent for some desperate glory,
The old Lie; Dulce et Decorum est
Pro patria mori.

Wilfred Owen
8 October 1917 - March, 1918