Question: What collection of whimsical poems by T. S. Eliot featured the poem Gus: The Theatre Cat?

Context paragraphs:
Burnt Norton: Burnt Norton is the first poem of T. S. Eliot's "Four Quartets".  He created it while working on his play "Murder in the Cathedral" and it was first published in his "Collected Poems 1909–1935" (1936).  The poem's title refers to a Cotswolds manor house Eliot visited.  The manor's garden served as an important image within the poem.  Structurally, the poem is based on Eliot's "The Waste Land" with passages of the poem related to those excised from "Murder in the Cathedral".

Gus: The Theatre Cat: "Gus: The Theatre Cat" is a poem by T. S. Eliot included in Old Possum's Book of Practical Cats.  Known as "The Theatre Cat" due to his career as an actor, Gus is an old and frail, yet revered, cat, who "suffers from palsy, which makes his paws shake."  His coat is described as "shabby" and he is "no longer a terror to mice or to rats."

Old Possum's Book of Practical Cats: Old Possum's Book of Practical Cats (1939) is a collection of whimsical poems by T. S. Eliot about feline psychology and sociology, published by Faber and Faber.  It is the basis for the musical "Cats".

Whispers of Immortality: "Whispers of Immortality" is a poem by T. S. Eliot.  Written sometime between 1915 and 1918, the poem was published originally in the September issue of the "Little Review" and first collected in June 1919 in a volume entitled "Poems" published by Leonard and Virginia Woolf's Hogarth Press.  It is one of the quatrain poems, a mode that Eliot had adapted from the mid-19th-century French poet Theophile Gautier.  The title is a fainter parody of William Wordsworth's title of the poem, "".

Pat Hall: Beryl Patricia Hall, née Woodhouse (13 June 1917–26 August 2010) (cited in ornithological literature as B.P. Hall and in self-published works as Pat Hall), was a British ornithologist, associated with the Natural History Museum.  She is best known for her work on African birds.  She also wrote a book of whimsical poems with Derek Goodwin called the "Bird Room Ballads" (1969).

A Witness Tree: A Witness Tree is a collection of poems by Robert Frost, first published in 1942.  The collection was awarded the Pulitzer Prize for Poetry in 1943.  Most of the poems in this volume are short lyrics.This collection was published after several unfortunate tragedies had occurred in Frost's personal life i.e.his daughter Marjorie's death in1934, his wife's death in 1938,his son Carol committed suicide in 1940. Despite these losses, Frost continued to work on his poetry and eventually fell in love with his secretary Kay Marrison ,who became the primary inspiration of the love poems in this collection.  This collection is the last of Frost's books that demonstrates the seamless lyric quality of his earlier poems.  The most popular poem of this volume is "The Gift Outright ",a patriotic poem that was recited at the presidential inauguration of John F. Kennedy in 1961.

Four Quartets: Four Quartets is a set of four poems written by T. S. Eliot that were published individually over a six-year period.  The first poem, "Burnt Norton", was written and published with a collection of his early works following the production of Eliot's play "Murder in the Cathedral".  After a few years, Eliot composed the other three poems, "East Coker", "The Dry Salvages", and "Little Gidding", which were written during World War II and the air-raids on Great Britain.  The poems were not collected until Eliot's New York publisher printed them together in 1943.  They were first published as a series in Great Britain in 1941 to 1942 towards the end of Eliot's poetic career.

A Song for Simeon: A Song for Simeon is a 37-line poem written in 1928 by American-English poet T. S. Eliot (1888–1965).  It is one of five poems that Eliot contributed to the "Ariel poems" series of 38 pamphlets by several authors published by Faber and Gwyer.  "A Song for Simeon" was the sixteenth in the series and included an illustration by avant garde artist Edward McKnight Kauffer.  The poems, including "A Song for Simeon", were later published in both the 1936 and 1963 editions of Eliot's collected poems.

The Hollow Men: "The Hollow Men" (1925) is a poem by T. S. Eliot.  Its themes are, like many of Eliot's poems, overlapping and fragmentary, but it is recognized to be concerned most with post-World War I Europe under the Treaty of Versailles (which Eliot despised: compare "Gerontion"), the difficulty of hope and religious conversion, and, as some critics argue, Eliot's own failed marriage (Vivienne Haigh-Wood Eliot might have been having an affair with Bertrand Russell).  The poem is divided into five parts and consists of 98 lines of which the last four are "probably the most quoted lines of any 20th-century poet writing in English".

Journey of the Magi: Journey of the Magi is a 43-line poem written in 1927 by T. S. Eliot (1888–1965).  It is one of five poems that Eliot contributed for a series of 38 pamphlets by several authors collectively titled "Ariel poems" and released by British publishing house Faber and Gwyer (later, Faber and Faber).  Published in August 1927, "Journey of the Magi" was the eighth in the series and was accompanied by illustrations drawn by American-born avant garde artist Edward McKnight Kauffer (1890–1954).  The poems, including "Journey of the Magi", were later published in both editions of Eliot's collected poems in 1936 and 1963.

Supporting paragraphs: Gus: The Theatre Cat Old Possum's Book of Practical Cats
Answer: Old Possum's Book of Practical Cats