World War 1 Medical Slings 'ELLO World War 1 Medical Slings Previous: Begbie Oil Signal Lamp – The Begbie Signal Lamp came into use in the 1880’s. It has a powerful lens to focus the beam and a shutter operated by a knob on top of the lamp. The operator pointed the lamp towards the next signal station and flashed his message in the Morse code by working the shutter. Next: Horsa Airspeed Glider drawing – The Horsa Glider was designed by Airspeed and to carry a load of about three tons such as a jeep and a light artillery piece or trailer, or a platoon of twenty-eight infantrymen. The Horsa was towed by a heavy bomber or a Dakota transport plane.