Traquair House Library (created between 1700 and 1740) has a collection of about 3000 books that has remained almost intact since the library was first formed. An unusual arrangement of the library has portraits of philosophers and writers around the ceiling as a device for cataloguing the books. For example, all the books under Pythagoras, are marked on the spines PYTH. Under the name are two numbers. The first number is the shelf number and the second is its position on the shelf.