Nathaniel Portlock ( 1748 - 1817 ) was a painter. Nathaniel Portlock s works have been auctioned off multiple times, with realized prices varying according to the size and medium of the artwork, for instance of 1060.89 USD for A Voyage Round the World; but more particularly to the North-West Coast of America: Performed in 1785, 1786, 1787, and 1788, in in 2005