Off the Western coast of Scotland, a nearly 400-year-old first edition copy of William Shakespeare’s collected plays has been discovered. The book was found in a huge aristocratic house on the Isle of Bute.

The First Folio contains Shakespeare’s 36 plays, including many that had never been published before and might have been lost without it. Few of them are “Macbeth,” “The Tempest” and “As You Like It.”

The book was published in 1623, says The Sydney Morning Herald.

While one has to read it sitting at a desk, the book is usually a single volume. However, the Bute copy was divided in the past for ease of reading.

It was split into three leather-bound volumes, one each for comedies, histories and tragedies.

Due to the Mount Stuart discovery, the total number of existing copies of the First Folio is now 234 in the whole world. Most others are in libraries and can only be accessed by scholars.

Original copy of the First Folio.. At the guildhall art gallery #guildhall #shakespeare

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According to a professor of Shakespeare studies at Oxford University, Emma Smith, the copy is £2 to 2.5 million pounds ($3.7 to $4.6 million) in worth.

Shakespeare’s Folio is not up for sale. It will be on public display at Mount Stuart until October, says Stuff.

It was found in the grand neo-Gothic home’s library that belonged to the Marquesses of Bute. The place also contains a collection of artworks and artefacts collected by the Stuart family over the centuries.

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“This is something that you could take to the fireside and enjoy,” said Smith. She authenticated the Bute Folio.

“It’s a book we most likely now see … in a glass case, and one of the things that this copy … shows us is a time when people just really used this book, they enjoyed it, they scribbled on it, they spilt their wine on it, their pet cats jumped on it.”

Celebrations are going to take place in Britain this year to commemorate the 400th anniversary of Shakespeare’s death on April 23, 1616.

The first-page inscription on the Folio was from an 18th-century editor of Shakespeare called Isaac Reed. There he described how he acquired the book in 1786.

The Folio was authenticated by several methods including a painstaking word-by-word reading.