The River
By Peter Heller. (Alfred A. Knopf, 253 pages, $25.95.)

"Unless we are very lucky, someone is going to die," one of the adventurers in Peter Heller's new novel says. Like his last book, "The Dog Stars," "The River" is a beauty-of-nature/cruelty-of-humanity hybrid, but this time he leans into the thriller aspect of the tale, with gripping results.

That adventurer could be referring to a couple of things: the massive forest fire that Heller describes almost like it's a monster pursuing his two main characters, young friends on a Canadian canoeing trip. Or the possibly murderous fellow outdoorsman they tangle with, who literally has them in his sights for most of the book.

Former Outside magazine editor Heller puts his knowledge of canoeing and currents to fascinating use. He has created indelible characters in Wynn and Jack, pals who are almost exact opposites: the former a bearish galoot who's convinced that people are basically good, and the latter a pessimist who's convinced that their only hope for salvation is to paddle as fast as they can.

CHRIS HEWITT

The Book of Delights
By Ross Gay. (Algonquin Books, 274 pages, $23.95.)

The premise behind Indiana poet and teacher Ross Gay's first work of prose, "The Book of Delights," is alluring. Every day or so for a year after his 42nd birthday, he will write an "essayette" on something that has given him a flash of joy — glimpses of beauty, sweet encounters with strangers, humorous moments, unexpected reprieves from boredom or pain, some sight he has eagerly twisted his head toward "like a sunflower." (It also acknowledges many painful moments, as when Gay shares his black father's story of how his white grandmother shook his hand only reluctantly, then wiped it on her apron, upon meeting him in 1971 in Verndale, Minn.)

This unusual and imaginative book is likely to inspire many readers to hone what Gay calls "a delight radar" and to create "delight journals" of their own. The problem is, Gay's essays aren't particularly delightful. For every one that's full of grace, such as one exploring the comfortable, unspoken trust that strangers riding together in a train feel after an extended time, there's a goofy, indulgent one, such as a three-pager on how Gay collects his own urine to use as fertilizer, and how this one time his girlfriend's daughter grabbed a bottle of it thinking it was a soft drink. Not delightful.

In addition, the essays are packed with allusions that will send even well-read readers to Google, an exercise that gets in the way of the reader's delight. The writing is often careless, full of long, winding sentences that appear to have been dashed off. Perhaps such spontaneity is the point, but it makes for a bit of a struggle on our part. Gay has a passion for social justice and a fine and curious eye, but his pen wanders too much into things that feel banal rather than delightful. His idea will inspire, but the execution falls short.

Ross Gay will be at Magers & Quinn at 7 p.m. on March 5.

PAMELA MILLER