Amazon, the online retailer, has been selling its Kindle digital book reader for nearly three years now, one of a handful of these electronic devices, including the recent Apple iPad that combines a bunch of "applications" that the other digital readers lack.

Despite the makers' suggestions that the device will make the old-fashioned print book extinct, it seems clear, for some time to come, at least, that these "appliances" are alternatives to books, not replacements.

My two-week experience with a Kindle last year convinced me that it's fine for reading straightforward narrative fiction and nonfiction while traveling, but it's a cold, impersonal experience for a "dinosaur" like myself, not raised on computer screens.

And, it's the screen itself that limits the eyes from roaming around unlike a standard book with its two-page view, as though you are inhabiting the story rather than getting it in restricted chunks.

No matter. E-book readers are selling well. Apple said last week it had sold 3.27 million iPads since April. Amazon said Kindle sales have tripled. Sony chimed in as well, claiming to have scored 10 million book sales at its online download store.

What boosted those sales was price cuts. Barnes & Noble sells a Nook model for $149; Amazon dropped the Kindle from $259 to $189 recently.

Amazon raised the level of its aggressive marketing strategy last week when it announced that e-book sales have surpassed print book totals on its website.

"Over the past month, for every 100 hardcover books Amazon.com has sold, it has sold 180 Kindle books," the company said.

Jeff Bezos, founder and CEO, called the event "the tipping point" for digital books, meaning his company's digital-book department and its Kindle.

Perhaps we should place that claim into perspective.

As Michael Cader of the trade observer Publishers Lunch pointed out, sales of print books last year were 205 million, a number that must reduce digital book numbers to insignificance at this point -- if we had those figures, but Amazon won't provide specific numbers, either for book or Kindle sales.

Two weeks ago, Amazon did announce that it had sold 867,881 digital versions of novels by James Patterson. Nora Roberts, Stieg Larsson, Charlaine Harris and Stephenie Meyer have also sold more than half a million copies each of Kindle books, Publishers Lunch reported.

The late Mr. Larsson's books are published in America by Alfred A. Knopf, which revealed last week that it had posted e-book sales of his crime trilogy of more than 1 million. Knopf also said that Kindle sales for "The Girl Who Kicked The Hornet's Nest," the newest and final installment, have "outpaced physical sales on Amazon."

Obviously, the Bezos book giant is making a statement about the direction of books that's drawing reactions across the publishing industry. E-book sales are "growing week by week," an anonymous representative of a major publishing house told the trade magazine Publishers Weekly.

PW also reported that print and digital versions were sharing equally in sales at other houses, backing up Mr. Bezos' claim, but other factors are contributing to the jump.

Amazon simply sells more e-books than print ones and those sales include books formatted for Kindle's competitors. Then there was the questionable decision by some big publishers to release print and digital versions of new books simultaneously, rather than giving the traditional version a few months to establish itself before delivering its digital format.

Regardless, e-books, powered by Amazon's marketing power and a choice of reading devices are firmly established and should only improve as their technology improves and the price comes down. Forests can now breathe a little easier.

Print books, though, are not in jeopardy of disappearing entirely. We readers now have the best of all possible worlds.

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