I came long ago to be suspicious of the encyclopedic impulse, the naive notion that knowledge could be captured and condensed in its entirety in a way that would not reduce its value. Encyclopedias of birds, birding, birdlife, whatever they are called, seem particularly susceptible to superficiality, and browsing most of them gives me what we used to call the willies.

Not so the new edition of Christopher Leahy’s Birdwatcher’s Companion, which in spite of its geeky title is as much fun to read as it is informative, even (get this!) accurate. From “abbreviations” to “zygodactyl,” by way of “imagination,” “rodent-run,” and “Teratornis,” the articles in the Companion cover a nearly overwhelming range of topics in ornithology, birding, history, and culture, all presented in an engaging and easy style. Leahy wears his considerable erudition lightly, and even the most casual reader will laugh out loud at the wit that shines through in sometimes the least expected places.

But the Companion is not likely to find many casual readers. Grabbing the thick, sturdy volume from the shelf, one may well intend only to check on the correct pronunciation of “Botteri” (accent on the first syllable, please) or the top speed of the Peregrine (verified at “only” 82 mph); but the book is seductive, and it will suck even the most single-minded user in with its recipes for American Coot, its mildly X-rated etymology of the word “stork,” its musings on the color “hepatic.” One topic suggests another, and one clearly and engagingly written article leads inexorably to “just one more,” until one is no longer consulting the book but reading it. The fine illustrations by Gordon Morrison are equally appealing, and range from plans for a Wood Duck box to the skeleton of a Northern Gannet.

The Companion first appeared 25 years ago, mirabile dictu, but the new edition, recently released in paperback, represents a thorough revision, many articles added and many others completely rewritten. While typographical errors are quite frequent, more substantive lapses are scarce (though oddly concentrated: the poor alcids fare particularly badly, for some reason, with the Long-billed Murrelet styled “Long-tailed,” the nesting sites of Ancient Murrelets moved high into the trees, and the length of the largest auks given as an intimidating 62 inches). Such slip-ups are, I am sure, only rarely the author’s fault.

Ned Brinkley’s gracious and graceful Introduction sings the praises of this book as a guide and a gift for the non-birder. I could not agree more; but birders too, no matter how inexperienced, no matter how sophisticated, will be charmed, amused, and educated by what is not just a reference book, but in the truest sense of the word a companion.