More fixes from the Lancaster doc review. (#453)

docs/reference/images/arrow-number.md

@@ -0,0 +1,33 @@
+# arrow Number
+
+Get the number that matches an arrow image name.
+
+```sig
+images.arrowNumber(ArrowNames.North)
+```
+
+Each arrow image name has a number for it. You can find the number for any arrow name with ``||arrow number||``.
+
+## Parameters
+
+* **arrow**: the arrow name to get an arrow number for. These are the arrow names:
+
+>* `North`
+* `NorthEast`
+* `East`
+* `SouthEast`
+* `South`
+* `SouthWest`
+* `West`
+* `NorthWest`
+
+## Example
+
+Get the arrow number for `ArrowNames.South`.
+
+```blocks
+let arrowSouthNumber = images.arrowNumber(ArrowNames.South)
+```
+## See also
+
+[arrow image](/reference/images/arrow-image)