Step inside the National Library of China and peruse over fifty restored ancient books, carefully selected from a collection of 16,000 Dunhuang manuscripts. Discovered in the Mogao Caves over a century ago, these documents dating back from the 4th to 11th centuries offer an insight into the history and culture of the dynasties over time.

This tremendous undertaking is led by Hu Bo, who is the head of the Document Restoration Team at the National Library of China.

His team operates in a 600-square-meter workshop, where they constantly restore ancient books. Each desk holds a priceless book awaiting the expertise of these "book doctors." Preparation work, often longer than the restoration process itself, is essential for a successful outcome.

Hu Bo revealed that they need to record the pH value of the books on a regular basis before attempting to restore them, as acidity affects fiber degradation. "Maintaining a neutral pH is crucial to preserving the documents," he added.

Following the testing phase, restoration experts carefully select the paper that closely matches the original document's material, weave and thickness. This pivotal step determines the success of the restoration process.

Matching the color of the restoration paper to the original document is the next step. Using pure Phellodendron amurense dye, consistent with the material used in the Dunhuang manuscripts, the team ultimately strives for authenticity.

"After trying various dyeing techniques, we achieve the right color," said Hou Yuran, a specialist from the Document Restoration Team, "We aim for slight visual differences to distinguish repaired areas while maintaining a cohesive appearance."

With the meticulous preparation process completed, the team embarks on the manual restoration stage. Severe fractures and abrasions are the primary causes of damage, requiring patience and precision to repair. Every character has to be aligned accurately, and meticulous pressing and adjustment are undertaken for each section.

"Each character needs to be positioned accurately, and each part requires careful pressing and adjusting," said Hou.

Over the decades, generations of restorers from the National Library of China have revived numerous precious cultural relics, including the Dunhuang manuscripts and the "Yongle Encyclopedia." Their skillful hands breathe new life into these ancient books, preserving Chinese civilization for future generations.

For Hu Bo and his team, it is a very honorable pursuit that also holds great significance for them to take part in the restoration of these precious ancient books.

"Whenever we restore a damaged ancient book and bring it back to its original condition and appearance, we appreciate the significance and value of our work," Hu Bo said.

Hou echoed Hu's view, saying that "preserving paper is preserving our civilization. It's our responsibility to extend its lifespan and safeguard our cultural heritage."

The book restoration team at the National Library of China meticulously revives time-ravaged and damaged ancient books, comparing their work to that of skilled doctors. Through their dedication, these treasures are reborn, ensuring the vitality of Chinese civilization for future generations.