A British observer drops from the car of a kite balloon, attached to the parachute which is hanging over the side of the basket. His colleague has already jumped and is on his way to the ground. The observations balloons were tethered to the ground, but if a sudden squall were to blow up, there was the risk of the cable snapping and the balloon drifting over enemy held territory. In such circumstances, charts and instruments would be thrown out and then each observer in turn would make what was known as 'the drop out'. Hopefully they would land safely, and not behind enemy lines.