Introduction to the Yuhai Library: When the library was first built, it contained 80,000 to 90,000 volumes of books, and now it contains more than 30,000 volumes. On the day when the Yuhai Tower was built, Sun Yiyan wrote 16 articles of the "Book Collection Regulations" , stipulates the circulation method of the book collection and prohibits anyone from taking books out of the building to protect the book collection.