Canvas respirator, 1918 (c)

Canvas respirator, 1918 (c)

Gas alarm whistle, 1918 (c).

Gas alarm whistle, 1918 (c).

Gas rattle used by Lieutenant J T Colledge, 1918 (c).

Gas rattle used by Lieutenant J T Colledge, 1918 (c).

Soldiers Advancing across no man's land in the mist

Soldiers Advancing across no man’s land in the mist

Through gas and smoke… Passchendaele Ridge, 1917.

Through gas and smoke… Passchendaele Ridge, 1917.

A soldier writing, Lievin, 1917 (c).

A soldier writing, Lievin, 1917 (c).

Notebook - Captain Siegfried Sassoon, 1917 (c). 1 of 3.

Notebook – Captain Siegfried Sassoon, 1917 (c). 1 of 3.

Tommy's smoke hat', 1915 (c).

Tommy’s smoke hat’, 1915 (c).

Gas alarm at Beaumont Hamel, December 1916.

Gas alarm at Beaumont Hamel, December 1916.

Consulting a map, 1917.

Consulting a map, 1917.

A soldier wearing a gas hood, 1917 (c).

A soldier wearing a gas hood, 1917 (c).

Corporal Joseph Egerton in gas mask, 1917 (c).

Corporal Joseph Egerton in gas mask, 1917 (c).

Under cover of gas and smoke..., 1916.

Under cover of gas and smoke…, 1916.

Gas Alarm! 1917 (c).

Gas Alarm! 1917 (c).

The latest pattern gas helmet with expiratory valve', 1915.

The latest pattern gas helmet with expiratory valve’, 1915.

French troops don their gas masks, 1915 (c).

French troops don their gas masks, 1915 (c).

Gassed British soldiers marching along a French road, 1916 (c).

Gassed British soldiers marching along a French road, 1916 (c).

'Poisonous Gas. Tear Gas-1917'.

‘Poisonous Gas. Tear Gas-1917’.

Infantry in gas hoods, 1915 (c).

Infantry in gas hoods, 1915 (c).

Effects and equipment used in gas attacks during the war