Putti forging and sharpening arrowheads on a millstone, after Francesco Albani

Albani's painting was in the Palazzo Santacroce (now Pasolini) when Fragonard and Saint-Non were in Rome at various times between 1759 and 1761. The painting was one of four oval canvases representing the four seasons that Albani executed around 1640. Fragonard's drawing shows a detail of two putti turning a millstone to sharpen a bow in the composition of Winter which included references to fire, with Venus, Cupid and Vulcan at a forge (for the paintings see C.R. Puglisi, A study of the Bolognese-Roman painter Francesco Albani, PhD. diss., New York University, 1983, pp. 313-15).
There is a counterproof of this drawing in the Biblioteca Universitaria, Warsaw.