Operation of "Catch Me Who" was hindered by the soft ground that the track was laid on. Trial runs began around 24 July 1808, but almost immediately the ground under the track sank, causing the iron rails to break as the 8-ton locomotive passed over them. Trevithick had the track taken up and timber baulks laid under it to provide a more stable footing. By 28 July, almost all the track had been relaid and the train ran again soon afterwards.