Because The Elements is, indeed, foremost a thing of beauty. It's actually the electronic version of a Gray's 2009 printed coffee table book of the same title, both shimmering with gorgeous images: the versatile element carbon is illustrated by the bright glitter of diamonds, the radioactive element radium is shown through the eerie blue-green glow of a vintage watch dial. But in the e-book version, these come playfully to virtual life. Some of the elements display in video; nitrogen as a flask swirling with an icy mist of the element in liquid form. Or the reader can set the still images spinning, the diamonds flashing, a vial of gold dust rotating front-label to back. The elements can even been seen in 3D if one purchases the special glasses (which I did not). And it includes an audio recording of Tom Lehrer's classic The Elements Song, which I have played so many times that I am now refusing to disclose the number.

In other words, it's game-like fun in a way that a coffee table book, even with same lovely photos by Gray's colleague, Nick Mann, cannot be. And it's worth noting that the e-version is sold as an app rather than an e-book. When I decided to give in and download it, I searched fruitlessly through iBooks before discovering it instead in the App Store (On the Touch Press website, it's offered strictly as an iPad app and an iPhone app.) I settled for the iPad version.

So is it actually a book, you might ask, if it's not even sold in a book store, if it's available on a few limited devices? Isn't one of the great achievements of the print publishing era, the ability to share information universally rather than limit it to a select few? And is my ability to spin a virtual copper necklace in comparable to what I learn from reading about that element in straightforward text? I think The Elements - and its undoubted success - raise all of those questions and more. And I think we're still figuring out the answers along with the future of the publishing business.

But let me briefly make a couple of other comparisons between this and its print version. Both do contain scientific data about each element (atomic number, weight, etc.) In the print book, of course, there's a treasure trove of this right there on the page. In the e-version, there's a compact summary but also much, much more through clicking on the Wolfram Alpha logo. You'll see the logo in the toolbar at the lower right on the image of the Bismuth page I've shown above; it looks like a fancy red star. This represents one of the ongoing tradeoffs as we move away from print - there's less likelihood of casual acquisition of information. But if we do seek out the online data, it's likely to be more current and more detailed - Wolfram Alpha allows you to go beyond its own database through links to a host of additional scholarly sources.