Ran farther than the others.
Carried the idea farther.
The farther shore.
I went no farther that day.
An example of farther used as an adverb is in the sentence, "The pink coffee mug was placed farther away than the green one," which means that the distances away from the starting point were measured for both mugs and the green coffee mug is closer.
An example of the use of farther as an adjective is in the sentence, "The blue house is farther down the street than the brown house," which means measurements to both houses from the starting point were taken and the brown house is closer to the starting point than the blue house.