Old books, like old money, need to be translated into today's values
Today there are numerous ways to know what the asking prices of books are and as Mike Stillman has correctly pointed out these are the prices of all the books that have not sold. What we show you are almost a million records of books, manuscripts and ephemera that have sold and we adjust the prices to current value. Now, for the first time, you can obtain a reasonably good idea of what your book is worth using a systematic process that identifies appropriate records, adjusts them to current value and averages them to provide you with a single valuation. Stray and inconsistent records are easily checked and eliminated if inappropriate.
Ultimately a seller may not agree to sell at the historically derived value but there is simply no reason not to know what the market history is. If you don't want to know it before you buy you will in any event learn all about it when you decide to sell. It's called reality. You may well have to pay more to buy material than these projected valuations suggest but you will also feel empowered to buy when the offers are well below what history suggests the real value is. Most booksellers want to sell their books. Some become argumentative if you discuss price but most will listen to an offer. If, in a reasonable amount of time, they believe they'll sell their book for their price they aren't going to discuss any concessions. If not, they will prefer to negotiate rather than lose the chance to sell their book to a knowledgeable buyer. This software helps both buyers and sellers to find the middle ground.
The development of this project has been undertaken by Mike Stillman, evaluated by Jenny McKinney who has already proposed a second version we'll begin work on this summer and implemented by Wei-cheng Chu, our software engineer. It is an important step in the evolution of bookselling on the net.
If you would like to sign up for a week or a month to give this software a work out click here and we'll take you to the sign-up page. A one week sign up is $7.95, a month $14.75, a year $141.60. For years the book business has been all about "asking prices." This is a step toward building the "bid side."
Il Ponte, Feb. 25-26: HAMILTON, Sir William (1730-1803) - Campi Phlegraei. Napoli: [Pietro Fabris], 1776, 1779. € 30.000 - 50.000
Il Ponte, Feb. 25-26: [MORTIER] - BLAEU, Joannes (1596-1673) - Het Nieuw Stede Boek van Italie. Amsterdam: Pieter Mortier, 1704-1705. € 15.000 - 25.000
Il Ponte, Feb. 25-26: TULLIO D'ALBISOLA (1899-1971) - Bruno MUNARI (1907-1998) - L'Anguria lirica (lungo poema passionale). Roma e Savona: Edizioni Futuriste di Poesia, senza data [ma 1933?]. € 20.000 - 30.000
Il Ponte, Feb. 25-26: IL MANOSCRITTO RITROVATO DI IPPOLITA MARIA SFORZA. TITO LIVIO - Ab Urbe Condita. Prima Decade. Manoscritto miniato su pergamena, metà XV secolo. € 280.000 - 350.000
Sotheby's Fine Books & Manuscripts Available for Immediate Purchase
Sotheby’s: Balthus, Emily Brontë. Wuthering Heights, New York: The Limited Editions Club, 1993. 6,600 USD.
Sotheby’s: Charles Dickens. Complete Works, Philadelphia & London: J.B. Lippincott Company & Chapman & Hall, LD, 1850. Limited Edition set of 30 volumes. 7,500 USD.
Sotheby’s: John Lennon, Yoko Ono. Handwritten Letter from John Lennon and Yoko Ono to their Chauffer. 1971. 32,500 USD.
Sotheby’s: Winston Churchill. First edition of War Speeches, Cassell and Company, Ltd., 1941. Set of 7 volumes. 5,500 USD.
Sotheby’s: Andy Warhol, Julia Warhola. Holy Cats First Edition, Signed by Andy Warhol. 1954. 30,000 USD.
Forum Auctions Online: India Ends 19th February 2026
Forum, Feb. 19: Lot 40 Ramasvami (Kavali Venkata). A Digest of the Different Castes of India, 83 charming hand-coloured lithographed plates, Madras, 1837. £5,000-7,000
Forum, Feb. 19: Lot 50 Watson (John Forbes) & John William Kaye. The People of India: A Series of Photographic Illustrations...of the Races and Tribes of Hindustan, 8 vol., 480 mounted albumen prints, 1868-75. £4,000-6,000
Forum, Feb. 19: Lot 53 Afghanistan.- Elphinstone (Hon. Mountstuart). An Account of the Kingdom of Caubul, first edition, hand-coloured aquatint plates, a fine copy, 1815. £2,000-3,000
Forum, Feb. 19: Lot 57 [Album and Treatise on Hinduism], manuscript treatise on Hinduism in French, 31 watercolours of Hindu deities, Pondicherry, 1865. £3,000-4,000
Forum, Feb. 19: Lot 62 Allan (Capt. Alexander). Views in the Mysore Country,
[1794]. £2,000-3,000
Forum Auctions Online: India Ends 19th February 2026
Forum, Feb. 19: Lot 76 Bird (James). Historical Researches on the Origin and Principles of the Bauddha and Jaina Religions..., first edition, lithographed plates, Bombay, American Mission Press, 1847. £3,000-4,000
Forum, Feb. 19: Lot 100 Ceylon.- Daniell (Samuel). A Picturesque Illustration of the scenery, animals, and native inhabitants, of the Island of Ceylon: in twelve plates, 1808. £5,000-7,000
Forum, Feb. 19: Lot 123 D'Oyly (Charles). Behar Amateur Lithographic Scrap Book, lithographed throughout with title and 55 plates mounted on 43 paper leaves, [Patna], [1828]. £3,000-5,000
Forum, Feb. 19: Lot 139 Gandhi (known as Mahatma Gandhi,) Fine Autograph Letter signed to Jawaharlal Nehru, Sevagram, Wardha, 1942, emphasising the importance of education in rural communities. £10,000-15,000
Forum Auctions Online: India Ends 19th February 2026
Forum, Feb. 19: Lot 140 Gantz (John). Indian Microcosm, first edition, Madras, John Gantz & Son, 1827. £10,000-15,000
Forum, Feb. 19: Lot 146 Grierson (Sir George Abraham). Linguistic Survey of India, 11 vol. in 20, folding maps, original cloth, Calcutta, Superintendent Government Printing, 1903-28. £2,000-3,000
Forum, Feb. 19: Lot 195 Madras.- Fort St. George Gazette (The), No.276-331, pp.493-936 and Index to all of 1834 at end, modern half calf, Madras, 2nd July - 31st December 1834. £2,000-3,000
Forum, Feb. 19: Lot 205 Marshall (Sir John) and Alfred Foucher. The Monuments of Sanchi, 3 vol., first edition, 141 plates, most photogravure, [Calcutta], [1940]. £3,000-4,000
![<b>Il Ponte, Feb. 25-26:</b> HAMILTON, Sir William (1730-1803) - Campi Phlegraei. Napoli: [Pietro Fabris], 1776, 1779. € 30.000 - 50.000](https://ae-files.s3.amazonaws.com/AdvertisementPhotos/0372eeb9-97e1-47b2-baca-b3287d4704ee.jpg "<b>Il Ponte, Feb. 25-26:</b> HAMILTON, Sir William (1730-1803) - Campi Phlegraei. Napoli: [Pietro Fabris], 1776, 1779. € 30.000 - 50.000")
![<b>Il Ponte, Feb. 25-26:</b> [MORTIER] - BLAEU, Joannes (1596-1673) - Het Nieuw Stede Boek van Italie. Amsterdam: Pieter Mortier, 1704-1705. € 15.000 - 25.000](https://ae-files.s3.amazonaws.com/AdvertisementPhotos/8f9ce440-b420-4407-8293-eb8e1b38ca19.jpg "<b>Il Ponte, Feb. 25-26:</b> [MORTIER] - BLAEU, Joannes (1596-1673) - Het Nieuw Stede Boek van Italie. Amsterdam: Pieter Mortier, 1704-1705. € 15.000 - 25.000")
![<b>Il Ponte, Feb. 25-26:</b> TULLIO D'ALBISOLA (1899-1971) - Bruno MUNARI (1907-1998) - L'Anguria lirica (lungo poema passionale). Roma e Savona: Edizioni Futuriste di Poesia, senza data [ma 1933?]. € 20.000 - 30.000](https://ae-files.s3.amazonaws.com/AdvertisementPhotos/71bb9667-5d66-4aa8-96a2-9880c74a7a26.jpg "<b>Il Ponte, Feb. 25-26:</b> TULLIO D'ALBISOLA (1899-1971) - Bruno MUNARI (1907-1998) - L'Anguria lirica (lungo poema passionale). Roma e Savona: Edizioni Futuriste di Poesia, senza data [ma 1933?]. € 20.000 - 30.000")
![<b>Forum, Feb. 19:</b> Lot 57<br>[Album and Treatise on Hinduism], manuscript treatise on Hinduism in French, 31 watercolours of Hindu deities, Pondicherry, 1865. £3,000-4,000](https://ae-files.s3.amazonaws.com/AdvertisementPhotos/f70b3790-9b4a-4990-b402-f0322021c0de.jpg "<b>Forum, Feb. 19:</b> Lot 57<br>[Album and Treatise on Hinduism], manuscript treatise on Hinduism in French, 31 watercolours of Hindu deities, Pondicherry, 1865. £3,000-4,000")
![<b>Forum, Feb. 19:</b> Lot 62 Allan (Capt. Alexander). <i>Views in the Mysore Country,</i>
[1794]. £2,000-3,000](https://ae-files.s3.amazonaws.com/AdvertisementPhotos/ad2cf7b4-4d93-4231-a956-b440583b39b3.jpg "<b>Forum, Feb. 19:</b> Lot 62 Allan (Capt. Alexander). <i>Views in the Mysore Country,</i>
[1794]. £2,000-3,000")
![<b>Forum, Feb. 19:</b> Lot 123<br>D'Oyly (Charles). <i>Behar Amateur Lithographic Scrap Book,</i> lithographed throughout with title and 55 plates mounted on 43 paper leaves, [Patna], [1828]. £3,000-5,000](https://ae-files.s3.amazonaws.com/AdvertisementPhotos/5651043b-3c0d-4e2c-931f-72133bda9b36.jpg "<b>Forum, Feb. 19:</b> Lot 123<br>D'Oyly (Charles). <i>Behar Amateur Lithographic Scrap Book,</i> lithographed throughout with title and 55 plates mounted on 43 paper leaves, [Patna], [1828]. £3,000-5,000")
![<b>Forum, Feb. 19:</b> Lot 205<br>Marshall (Sir John) and Alfred Foucher. <i>The Monuments of Sanchi,</i> 3 vol., first edition, 141 plates, most photogravure, [Calcutta], [1940]. £3,000-4,000](https://ae-files.s3.amazonaws.com/AdvertisementPhotos/8c8244b7-4573-44d3-9c70-e0d3a3ed3cc4.jpg "<b>Forum, Feb. 19:</b> Lot 205<br>Marshall (Sir John) and Alfred Foucher. <i>The Monuments of Sanchi,</i> 3 vol., first edition, 141 plates, most photogravure, [Calcutta], [1940]. £3,000-4,000")