The Adventures of Sherlock Holmes1984

Sherlock Holmes:
You have come by train, I see, this morning.

Helen Stoner:
You know me, then?

Sherlock Holmes:
No, but I observe the second half of a return ticket in the palm of your left glove. You started early, but you had a drive in a dog-cart, along heavy roads, before you reached the station. There is no mystery, my dear lady: the left arm of your jacket is spattered with mud in no less than seven places, the marks are fresh. There is no vehicle save a dog-cart which throws up mud in that particular way, and then only when you sit on the left-hand side of the driver.

Helen Stoner:
You are perfectly correct.