Reinagle was also an accomplished copyist of the Dutch masters, and his reproductions of cattle-pieces and landscapes by Paul Potter, Ruisdael, Hobbema, Berchem, Wouwerman, Adriaen van de Velde, Karel Dujardin, and others have often been passed off as originals. He also made some of the drawings for Robert John Thornton's "New Illustration of the Sexual System of Linnaeus" (1799–1807), and for his "Philosophy of Botany" (1809–10) ; but his best drawings for book illustration were those of dogs for William Taplin's "Sportsman's Cabinet" (1803) which were engraved by John Scott.