The Felix tickets were the Willebrew system (think that's the right spelling). The machine guillotined a section out of the ticket which showed all possible fare values, and the highest visible value remaining was the fare paid. Audit consisted of retrieving all the cuttings from the conductors' machines, laboriously totting up each fare and comparing the total with the takings. OK perhaps for a smallish operator, but not much fun for a bigger operator. If I remember correctly Skills used the same system on their Nottingham-Shelford-East Bridgford route operated jointly with Trent. Talking of