The problem with an natural history museum like the American Museum of Natural History is one of scale. You buy your ticket (which is not cheap) and then you face halls and halls and halls of amazing, cool, historic, and one-of-a-kind artifacts. For the first few, you are properly amazed, marveling at the history around, fitting new pieces of information together in unexpected ways in your head.
The problem is that it's too much. There's no way to take it all in. Your poor human senses and brain are overwhelmed. You'd need six months, at least, to get a sense of the scope of everything and to be properly awed. But you have one afternoon. And, because you bought your ticket and hold museums in such high esteem, you force yourself through halls and exhibits long after the point that your brain has checked out. Your brain becomes the bored six year old you once were. Oh, look, another massively old, immensely historic, unique bit of human history. Another masterpiece. Yet another stunning jewel. Another piece of rock that has seen more millions of years than I can even imagine. Yet another ancient skull from somewhere in the human lineage. It begins to all just wash over you until you flee, in a cloud of guilt and exhaustion, feeling that you really didn't get the most out of your museum experience.
That's the problem this book faces and, to some degree, the problem it sets out to solve. Writing a full, comprehensive history of a museum is a mammoth task. That's why it's so rarely been done. There's just too much raw material, too many jaw-dropping stories, too much there there.
That being said, A Gathering of Wonders does an excellent job, within its scope. It's a wonderful romp through the halls of AMNH and a cherry picking of its most famous stories and personalities. The book is engrossing. It makes you want to move to the museum, and study one new object every day, learn one new discipline a month.
It's a wonderful tasting: you get a little bit of everything and not too much of any one thing. It's perfect for rambling reading. I highly recommend this book.