This and a second graphite and watercolor sketchbook drawing of cats today, by American painter C. Bertram Hartman (1882–1960), which I purchased from an artist/dealer in Cambridge, MA. This one with no year to the date (late 1940s I believe) but is stamped B. Hartman, R. Castellane Gallery. (The Richard Castellane gallery acquired the Estate Collection of Hartmann around 1960, from the former Rabin & Krueger Gallery Newark, New Jersey. ) I think it is a wonderful, very full of life drawing, for me all about gesture and specifically the exposure of the underbelly of the cat. (Perhaps this is the mother cat pictured in the other drawing?) With the application of the watercolor making it something of an abstract color field painting at the same time! 

Hartman studied at the Art Institute of Chicago, the Academy of Fine Arts Munich, and in Paris, then remained, with his wife Augusta ("Gusta"), based in New York City, where they was especially close to Gaston Lachaise and his wife Isabel Nagle Lachaise. In 1933/1934 Hartman was represented by two works in the first ever Whitney Biennial, with works held in the collections of the Whitney,  the Metropolitan Museum of Art, and the Brooklyn Museum, among other museum collections. He also produced numerous murals as part of the Federal Art Project of the Works Progress Administration.

9 1/2" x 7 5/8". Very good condition, graphite and watercolor strong, minimal toning. Rough right edge from spiral binding, could be trimmed.