He first gained employment as a shepherd for George Macleay and in 1838 he joined Charles Bonney in the first cattle drive from the Goulburn River to Adelaide.

In South Australia he successfully managed several large sheep properties and conducted exploration of the area.

In 1869 he explored the Stevenson River to Eringa and Mount Humphries; he named the mountains after his children, Sarah, Rebecca, Alexander and John.

In 1870 his then employer Thomas Elder recommended Ross' service to Charles Todd, the colony's superintendent of telegraphs and government astronomer.

Todd employed Ross to lead exploration of the route for the Australian Overland Telegraph Line.