<P> The poem Macavity the Mystery Cat is the best known of Eliot's Old Possum's Book of Practical Cats, the only book Eliot wrote for a younger audience . The poem is considered particularly suitable reading for 11 - and 12 - year - olds . </P> <P> Macavity (also called the Mystery Cat, the Hidden Paw and Napoleon of Crime) is a master criminal, but in the poem he is too clever to leave any evidence of his guilt . There is a resemblance with Professor James Moriarty from the Sherlock Holmes stories by Arthur Conan Doyle . In a letter to Frank Morley, Eliot wrote, "I have done a new cat modeled on the late Professor Moriarty, but he doesn't seem very popular; too sophisticated perhaps ." Sherlock Holmes describes Moriarty as "the Napoleon of Crime" in The Adventure of the Final Problem and a "Napoleon gone wrong" in The Valley of Fear . Evidence that Macavity was based on Moriarty was first presented by HT Webster and HW Starr in 1954, and later rediscovered by Katharine Loesch . </P> <P> According to the poem, even when the Secret Service decides that Macavity was behind a loss, they can't catch him, as "he's a mile away", "...(or) engaged in doing complicated long division sums". Doyle wrote that Moriarty "is never caught" as at the moment of the crime he is probably "working out problems on a blackboard ten miles away" (The Adventure of the Final Problem). Macavity is described as being a ginger cat who is very tall and thin with sunken eyes, and "sways his head from side to side with movements like a snake". The poem also says: "His brow is deeply lined in thought, his head is highly domed; His coat is dusty from neglect, his whiskers are uncombed ." Once again, this description is a close parallel to that of Professor Moriarty: </P> <P> "His appearance was quite familiar to me . He is extremely tall and thin, his forehead domes out in a white curve, and his two eyes are deeply sunken in his head...his face protrudes forward and is forever oscillating from side to side in a curiously reptilian fashion ." (The Adventure of the Final Problem) </P>

Who wrote the poem macavity the mystery cat