[7] Mankowski worked as a carver for John Donnelly & Company in the 1930s, a firm that supplied architectural sculpture for a number of Washington, D.C. federal buildings.

[1] Alongside carvers William Kapp, Roger Morigi and Otto Thieleman, Mankowski executed the work of sculptor Paul Jennewein for what is now the Robert F. Kennedy Department of Justice Building.

[8] The four men also carved Jennewein's Lege Atque Ordine Omnia Fiunt architrave (limestone, 1935), over the building's entrance.

[9] Fiorello LaGuardia, mayor of New York City, opposed Germany's participation in the exposition, and publicly proposed that the German Pavilion should be a "House of Horrors" of Nazi atrocities.

[9] In reaction, LaGuardia endorsed the idea of a Freedom Pavilion, that would exhibit works by German artists and exiles opposed to the Nazi Regime.

Grover Whalen, president of the New York World's Fair Corporation, had worked hard to secure Germany's participation, and resented LaGuardia's interference.

For the Works Progress Administration art program, Mankowski created The Farmer's Letter (1939), a plaster relief panel for the post office in Chesterfield, South Carolina.

Professor Thomas H. Osgood, Chair of the Physics Department, selected a number of illustrations from the History of Science, and these were incised into the limestone panels surrounding the building's entrance.

[15] Among the vignettes: Galileo and his solar system, Isaac Newton and his experiments with gravity, Benjamin Franklin and his kite, Marconi and his wireless telegraph, and Albert Einstein and the atom.

[20] As part of the 1949-1950 restoration of the U.S. Capitol, prominent American sculptors were commissioned to create twenty-three relief busts of historic lawmakers for the House Chamber.

Mankowski carved nine of the relief busts in marble, modeled by sculptors Gaetano Cecere, Jean de Marco, and Thomas Hudson Jones.

[24] Lee Lawrie modeled three relief panels for the Senate Chamber, including Courage, depicting a man battling with a serpent.

[28] In 1950, American Export Lines commissioned twin ocean liners from Bethlehem Steel's Fore River Shipyard in Quincy, Massachusetts.

Mankowski made life size models of his replica figureheads, but the plan for enlarging them and mounting them on the bows of the liners was abandoned.

In 1961, Jennewein was commissioned to create a group portrait of the library's late founders: Dr. John Shaw Billings, Dr. Robert Fletcher and Dr.

[33] His solution was essentially a larger-than-life drawing of the trio, its lines inscribed into the gray marble of library's lobby, then gold leafed.