Robert Porter Bringhurst ( 1855 - 1925 ) was an American painter. Robert Porter Bringhurst s works have been put up for auction numerous times, with realized prices surpassing estimated prices, varying from 40 USD for bust length figure of an Art Nouveau female in 2005 to 2500 USD for Bust of Mark Twain in 2005 , based on the size and medium of the artwork.