The stranger came early in February, one wintry day, through a biting wind and a driving snow, the last snowfall of the year, over the down, walking from Bramblehurst railway station, and...
According to OALD, down (n) means very fine soft feathers of a bird or fine soft hair; which I don't think is true in this context.
The excerpt is from the beginning of the novel, "The Invisible Man" by "H.G. Wells".
I'm learning English as a second language, and this book is a part of my school syllabus and has countless other similar phrases. Any suggestions would be helpful.