The solution eventually came to them. On 22 September 1915 Wilson and Tritton sent the now famous telegram to the Admiralty that said:
New arrival by Tritton out of pressed plate. STOP. Light in weight but very strong. STOP. All doing well Thank you. STOP. Proud parents.
Tritton was an engineer and he had used first principles to work out what design of track was required. The systems that they had been experimenting with up until now (Bullock, Holt, Hornsby) were fairly complicated systems. Tritton and Wilson came up with an unsprung system of interlocking links and a basic track tensioning system that they believed would stop the tracks from sagging and prevent them being thrown when driving over rough ground.
According to David Fletcher this new design of track was probably the single most important factor in the evolution of the British tank. A set was made for the No 1 Lincoln Machine and this new improved prototype became Little Willie.