Leopold (friedrich Hermann) Hartmann ( 1839 - 1897 ) was a German painter. Leopold (friedrich Hermann) Hartmann s works have been put up for auction numerous times, with realized prices surpassing estimated prices, varying from 482.55 USD for A spaniel on a cloth in 2004 to 2557.54 USD for Deux cardinaux jouant aux échecs in 2015 , based on the size and medium of the artwork.