Here's how they work:

* Short, closely spaced lines: Indicate a steep slope.

* Long, widely spaced lines: Indicate a gentle slope.

* The direction of the lines: Shows the direction of the slope.

* Thicker lines: May represent a steeper slope or a cliff.

Think of hachures as a series of lines showing the "downhill" direction on the terrain. The closer they are together, the faster you'd be going downhill!