Dirt By William Bryant Logan

From the author of the recent, acclaimed study Oak, comes this revelatory account of "the ecstatic skin of the earth". (Actually, he wrote the books in the right order; Dirt preceded Oak by a decade.) In a series of glancing, evocative essays, Logan explores the significance of dirt - he prefers the term to soil ("sexless and ugly") and earth ("confusing") - in prose as lively as poetry. He says the shore is "a laboratory of salts", while silt is "the soil when it daydreams". Both humus ("it may be the most disordered material on earth") and human derive from humorous, originally meaning wet, but Logan insists the parallels go further. "We are audacious, like nature itself... fecund, protean, dangerous." His subterranean saga touches on dowsing, dustbowls, decomposition of corpses, the stink of shellfish in a Florida landfill site ("beyond odour"), the watery underpinnings of many cathedrals and the resemblance of primitive digging sticks to penises. He is particularly good on worms: "slinky, slithery, slimy, blind and voracious... the embodiment of gross materiality." Though Logan's passion sometimes comes perilously close to sentimentality, this monograph on an unlikely subject is a minor masterpiece of startling originality. CH