When an exhibition of some original manuscripts of Dylan Thomas opens later this spring at Houghton Library, the Welsh poet will take his place beside Harvard's first charter and Edwin Booth's last cigar. Within the walls of the red-brick, air-tight, thief-proof building are not only one of the world's best known collections of rare books, but also University documents and historical curios.

To enter the building crowded between Lamont and Widener Libraries, one must first get past the watchful, wary doorman. Some special displays are behind locked show cases, but most books are in the reading room, which the person at the circulation desk can open only by a special switch. If the building seems more like a bank vault than a library, it is because it was planned to preserve perfectly every inch of every book in the collection. Constantly clicking machines check the temperature and humidity, and ultra-violet devices, microscopes, and micro-film viewers aid scholars in doing research.

Many of the library's oldest manuscripts date from before 1500, while others include first editions of Thomas Wolfe, Herman Melville, and Henry Wadsworth Longfellow. Houghton's theatre collection is one of its most unusual attractions--even holding the answer to "whether Macbeth should be played in quilts." A rare series of seventeenth century American almanacs, precursors to Poor Richard, are especially valuable and amusing. Among the wise saying are the following: 'All men like money; some their wives," and "He that marries for love has good nights but sorry days." The world's largest series of books and manuscripts by John Kcats occupies a special room and is the Library's most famous another collection.

Harvard's rare books and manuscripts have not always been in air-conditioned, dust-free splendor. John Harvard himself began the collection with a gift of "400 books to the Small college in new Cambridge." Stored in Harvard Hall, the books were safe until a free broke out one January night in 1764. A few books in circulation escaped the fire, but the only present-day survivor from that original library was a copy of John Downame's Christian Warefare Against the Deuill, World, and Flesh. A certain Mr. Briggs had fortunately failed to return the book on its due-date.

Gifts soon restored the library to its former size, and in 1775 when George Washinton's troops occupied the College buildings, one professor packed up the Harvard library in two days and trundled it off to Andover for safe-keeping. Gradually the library began to bulge with valuable books, and it moved from Harvard Hall to Gore Hall, located on Widener's current site, and then to the "Treasure Room" of Widener.

But it became clear that such a collection demanded a separate building, and in 1940 President Conant dug the first spadeful of earth from a hole that was to become the new rare-book library. When it was opened three months after the start of World War II, Houghton was described as "Fire-proof, earthquake-proof, and reasonably protected against the incendiary bomb." The age of nuclear weapons may have increased Houghton's vulnerability, but it has not diminished the value of a collection that has withstood three hundred years in the Yard.