At one point, while Father (Charles Chaplin) is stuck in the tar, he has lost his hat. He's still without a hat when the second policeman gets stuck in the tar, but after Chaplin steps out of his shoe and climbs over the two policemen, his hat has returned to the top of his head.
(at around 2 mins) As Father (Charles Chaplin) struggles with the cantankerous car, a pedestrian comes into view on the far sidewalk in the background. Either realizing a film is being shot or waved off by the crew, he turns around and walks away, but he pauses to look back over his shoulder just before he walks out of sight.