A big book that was so heavy it remained on the same shelf, untouched, for 23 years.
Heavy reading, they called it. But they meant that the tone, language and content made it hard to read.
By the time the shelves were replaced three people had read this enormous work.
It took two years to replace the bookshelves.
It took two days for those three people to start applying what they learned from reading the heavy work.