These photographs show different views of the two items my great uncle John Marshall acquired from the German trenches during the First World War.

The first is a gas bell which was rung to warn German troops of a gas attack from the British trenches. The gas both sides used was chlorine.  Chlorine is a most deadly gas, heavier than air which would sink to the lowest level and so sought out the troops in the trenches.  There was a chance of survival if you heard the bell ringing the warning and put your gas mask on, but many were killed in gas attacks.

The second item is a surveyor’s level.  I’m a surveying engineer myself so I was especially interested to acquire this when my great uncle died.  It’s about 160 years old and is beautifully crafted from brass.  Surveying was an essential part of trench warfare because you needed to map the area accurately, not just how far away the enemy might be but how the pattern and depth of the trench system.  This knowledge meant you could fire your shells with more deadly effect.