In the 15 years since the Harry Elkins Widener Collection of rare books became the property of Harvard University, its value has probably increased from $1,000,000 to $3,000,000, it was announced yesterday. This collection, which contains something over 3,200 volumes and manuscripts, stored in the Memorial room of the library, includes some of the most valuable books in the English language, both from a literary and from a monetary point of view.

There are in the assemblage numerous first editions and folios, among which a notable one is a first folio edition of Shakespeare, of which there is but one other copy in existence. This was bought by Mr. Widener for $20,000 not long after he graduated from Harvard, in 1907, and now has a value of at least $70,000. Although this is the price listed, it would be hard to procure one of the first folio editions even at that cost.

Another of the extremely valuable copies in the collection is the first edition of the "Martyrs" of John Foxe, entitled as follows: "Actes and monuments of these latter and perillous dayes, touching matters of the Church, wherein are comprehended and described the great persocutions and terrible troubles, that have been wrought and practised by the Romishe Prelates, speciallye in this Realme of England and Scotlande, from the yeare of our Lorde a thousande, unto the tyme nowe present." It has the original stamped vellum binding.

Among the first editions of several of William Makespeace Thackeray's works is a copy of "The History of Henry Esmond. Esq. A Colonel in the Service of Her Majest Queen Anne, Written by Himself." This is of particular interest because it is the presentation copy; inscribed in Thackeray's handwriting: "Miss Brote, with W. M. Thackeray's grateful regards. October 28, 1952."

An early work of great value is the first edition of Edmund Spenser's "Faerie Queene." This has the dedication: "To the most Mightie and Magnificent Empresse Elizabeth, by the grace of God QUeene of England, France, and Ireland, Defender of the Faith, &c. Her most humble Servant: Ed Spenser." This copy is full of misprints and mistakes in the numbering of the pages; on page 332 blank spaces have been left for the insertion of Welsh words.

One of the two complete copies of "King Arthur" is kept in the Widener collection. This book, the only replica of which is in the British Museum, is entitled, in full, "The story of the most noble and worthy Kynge Arthur, the which was the fyrst of the worthyes chrysten, and also of his noble and valyaunt knyghtes of the rounde Tablo." A small folio, olive morocco in color, and with gilt edges, this book is beautifully illustrated in the first portion, with fancy wood-cuts.

"The life of Samuel Johnson, LL.D. Comprehending An Account of His Studies and Numerous Works, in Chronological Order; a Series of his Epistolary Correspondence and Conversations with many Eminent Persons. And Various Original Pieces of His Composition, Never before Published. The whole Exhibiting a view of Literature and Literary Men in Great Britain, for Nearly Half a Century, During Which he Flourished," is the title of an exceptionally valuable edition.

An extremely rare piece of the collection is a group of 36 pages from the manuscript of "Pendennis," entirely in the hand-writing of its author, Thackeray. One page contains three original sketches, labeled "George Washington," "General Bonaparte," and one unnamed. There are six original rough and traced sketches, in pencil and pen and ink, of illustrations to "Pendennis," all by Thackeray.