William Callcott Knell ( 1830 - 1876 ) was a British painter. William Callcott Knell s works have been put up for auction numerous times, with realized prices surpassing estimated prices, varying from 442.91 USD for St. Omer, Strasbourg in 2004 to 33600 USD for Warships approaching the anchorage in 2007 , based on the size and medium of the artwork.