I recently got a copy of **Methods of Theoretical Physics** by Morse and Feshbach. It’s a dense book, literally and metaphorically. I wondered whether it might be the densest book I own, so I weighed some of my weightier books.

Morse and Feshbach has density 1.005 g/cm³, denser than water.

**Gravitation** by Misner, Thorne, and Wheeler is, appropriately, a massive book. It’s my weightiest paperback book, literally and perhaps metaphorically. But it’s not that dense, about 0.66 g/cm³. It would easily float.

**The Mathematica Book** by Wolfram (4th edition) is about the same weight as Gravitation, but denser, about 0.80 g/cm³. Still, it would float.

**Physically Based Rendering** by Pharr and Humphreys weighs in at 1.05 g/cm³. Like Morse and Feshbach, it would sink.

But the densest of my books is **An Atlas of Functions** by Oldham, Myland, and Spanier, coming in at 1.12 g/cm³.

The books that are denser than water were all printed on glossy paper. Apparently matte paper floats and glossy paper sinks.

How did you determine each book’s volume? Did you estimate it from the physical dimensions, dump each under water (I hope not), or do something else? — Clint

I measured each book and assumed it was a rectangular prism. The cover of hardbacks sticks out slightly from the pages, so I slightly over-estimated volume and hence slightly under-estimated density.

There were no densities slightly less than 1, so my conclusions about floating or not should hold.

Excellent. I would have been worried had you dunked each book in water. :-) Keep up the great work! — Clint

Glossy paper is often coated with kaolin, which is a very fine-grained aluminium silicate material. You can amuse people moving their library exactly once by pointing out that the boxes of art books are heavy because they’re literally made out of wood coated with rocks.

Clearly you lack a copy of Wolfram’s “A New Kind of Science”. Absolutely the densest book I’ve ever read the first five pages of.

I do have a copy of NKS. It’s conceptually quite dense, but not physically dense.