It has been a little difficult tracking down detail of the company. There was a brick manufacturer based in Wortley, Yorkshire. This company was establised by William Ingham in 1825 with his sons, Robert, Henry and Frederic joining him later. The firm extracted coal, ironstone and fireclay from its property at Wortley. The fireclay site alone covered 7 acres and employed 400-500 people. The company manufactured fireclay products that included 'firebricks, blast and other furnace lumps'. After 1889 they formed part of Leeds Fireclay Co Ltd.
At some point glazed art pottery was produced and the impressed number on this example would suggest a sizeable range. This example has a nicely thrown ribbed form with shiny veined turquoise glaze. Impressed marks on the underside "WORTLEY" together with a number 206. I have made an assumption that this brick maker is the same Wortley as this pot.
For more information on Wortley bricks, try; http://www.penmorfa.com/bricks/england8.html