What kind of poet turns cats into doggerel -- The sort that cavort on the National's stage? You might think Rod McKuen or hacks pseudonymical, But it's old T. S. Eliot, the Nobel-winning sage!

STRANGE AS IT SEEMS, the libretto for "Cats," Broadway's furry phantasmagoria of paws, maws and claws, comes from none other than that all-hallowed author of "The Waste Land," "Murder in the Cathedral" and "The Love Song of J. Alfred Prufrock," Thomas Stearns Eliot (1888-1965). The man who during his lifetime, as biographer Russell Kirk puts it, "had come to possess more cultural authority than anyone else could claim."

The Eliot oeuvre is not conspicuous for its whimsy. His principal genius lay in baring modern man's benumbed and hollow horror at life without spiritual meaning--and then in limning the painful ecstasy of the soul's awakening. It is demanding reading: His best-known work, "The Waste Land," is so cryptically allusive that the bard felt obliged to append footnotes (thus guaranteeing lifetime employment to legions of scholars).

Yet in his mid-forties, the St. Louis-born poet who became a classicist, royalist, Catholic and British subject, suddenly began composing cat poems redolent of the nonsense verse of Lewis Carroll and Edward Lear. The result, published in 1939, was "Old Possum's Book of Practical Cats"--15 short feline profiles on the Aesopian-fabular model, with each puss representing a different, um, category: Cats are much like you and me And other people whom we find Possessed of various types of mind.

Hence Mungojerrie and Rumpelteazer ("tightrope walkers and acrobats"), Macavity the Mystery Cat ("he's called the Hidden Paw--/ For he's a master criminal who can defy the law"), Jennyanydots (who "sits and sits and sits"), Rum Tum Tugger (maddeningly finicky), Old Deuteronomy (the village ancient), Mr. Mistoffelees, "the Original Conjuring Cat," and Bustopher Jones, "the Cat About Town." If the monikers are outlandish, well, Eliot wrote that each cat has three names: one for daily use, one uniquely its own (as above) and finally one "the cat himself knows and will never confess": When you notice a cat in profound meditation, The reason, I tell you, is always the same: His mind is engaged in a rapt contemplation Of the thought, of the thought, of the thought of his name; His ineffable effable Effanineffable Deep and inscrutable singular name.

Eliot's widow dates the kitty canon from a 1931 letter he wrote to his godson. In it, Eliot ironically praised his cat Jellylorum for its practicality ("its one idea is to be useful") and festooned the text with his own illustrations. By 1938 he had compiled more than a dozen such portraits and decided on the peculiar title. "It was Ezra Pound, you know, who dubbed me 'Old Possum,' " Eliot once explained to his friend William Levy, "and it seemed right to use it in the title of a collection of verse so different from anything I had published before."

But so in keeping with his character. "Children liked him," writes Kirk, "so did cats." Eliot warmly reciprocated. "The great thing about cats," he said, "is that they possess two qualities to an extreme degree--dignity and comicality." Oddly enough, so did he.

For all the pandemic gloom of his early work, Eliot was famous as a good-humored wit and lifelong addict to light verse. At Harvard he wrote a pedantic-salacious mock-epic on the imaginary "King Bolo and His Big Black Queen" ("whose bum was as big as a soup tureen"), later penned a number of scurrilous ballads ("excellent bits of scholarly ribaldry," said his friend, painter Wyndham Lewis) and planned a comic poem about a pig called Mr. Pugstyles after a Dickens character. And in the years before "Possum," despite his sadness when his first wife, Vivienne, was hospitalized for incurable neurosis, Eliot met regularly with a group that discussed Sherlock Holmes stories and ground out reams of forgettable humorous verse, which the members had privately printed and distributed.

He had even conceived a companion volume of dog ditties, the inspiration for which, Eliot's widow (his second wife, Valerie) remembers, came when a chauffeur was describing his own dog--a prole-blooded mutt--to the poet. "He is not," said the driver, "what you would call a consequential dog." Eliot found the notion so funny that he determined to write a book of 'Consequential Dogs' to accompany the 'Practical Cats,' but never completed the project.

Eliot was scarcely the first writer to put the cat out in print. Since the first yowling dawn of felinity (when the first rude sandal was hurled through a cave window), poets have found in cats' aloof, disdainful grace and unremitting selfishness an apt emblem for their craft. But "Old Possum's Book" is still selling, a children's favorite both here and abroad, where it has been translated into numerous languages.

Eliot acknowledged only one writer who had perhaps bested him on the subject: Christopher "Kit" Smart, the 18th-century couplet-bender who had the unfortunate habit of demanding that passers-by kneel down with him to pray in the street. For this pious quirk, among others, Smart was sent to the madhouse. Thus equipped with ample leisure, he composed his enormous poem, "Jubilate Agno," containing the immortal section dedicated to "my Cat Jeoffry/ For he is the servant of the Living God, duly and daily serving him . . . / For he will not do destruction if he is well-fed, neither will he spit without provocation." That mighty ode, Eliot once remarked, "is to all other poems about cats what 'The Iliad' is to all other poems on war."

Persons planning on seeing the stage show would be well advised to read Eliot's slim volume in advance. There may be difficulty in hearing the occasional jumble of high-snoot syntax ("At prestidigitation/ And at legerdemain/ He'll defy examination/ And deceive you again"), and some of the poems refer to unfamiliar locales and events. "Bustopher Jones," for example, is full of London restaurant names and exotic chows: "For a similar reason, when game is in season/ He is found, not at Fox's, but Blimp's; / But he's frequently see at the gay Stage and Screen/ Which is famous for winkles and shrimps."

Don't expect a transport of artistic rapture. One kindly critic has cited the poems' "great metrical brilliance"; but most would agree with Eliot scholar Burton Raffel's verdict: "pleasant, inoffensive and unremarkable."

And if after reading them, you find that all your reservations aren't at the box office, you're in good company. Even Old Possum himself was skeptical. The poems were recorded in England during his lifetime, read by Robert Donat with music by Alan Rawsthorne. On first hearing them, Eliot was pleased: "I like the idea that they are read against the musical background and not themselves set to music," he told Levy, "but I am not at all sure yet what I think of it, and, of course, I should have to hear them all."