When Roger Fenton drinks the full bottle of whisky in his office, from one angle it's empty and, from another, two-thirds full.
Roger's boss tells his wife he checks the speedometer every day for the mileage on the car that Roger has been using. It's the odometer, not the speedometer, that shows accumulated mileage on a car.
When Roger Fenton and John Braine are talking at a table in the bar, Slug eavesdrops from the next table, but Fenton does not seem to recognize him although they previously shared a prison cell.