Primo Levi: The Naturalist’s Eye : OTHER PEOPLE’S TRADES <i> by Primo Levi; translated by Raymond Rosenthal (Summit Books: $17.95; 222 pp.) </i>

As a young man, Primo Levi had hoped to pursue a career in scientific research, but World War II, deportation to Auschwitz and the need to make money after the war derailed his plans. On returning to Turin in 1945, he went to work as a technician for a paint factory and wrote in his spare time about his concentration camp experience and his life as a chemist. However, as this new volume makes clear, he never lost his early fascination with scientific speculation or his wistful fondness for the road not taken.

In short articles written for his local newspaper during the 1970s and 1980s, Levi began, as he puts it, invading “other people’s trades,” writing fancifully about everything from space travel and computer chess to the durability of beetles and phobias toward spiders and snakes. “Other People’s Trades” is a minor work, but it is nonetheless a welcome addition to the other Levi books now available in English. There has been a tendency since Levi’s tragic suicide in 1987 to view his life as having been dominated almost exclusively by the trauma of his experience at Auschwitz. This collection helps restore a full sense of the breadth and lively curiosity of his mind and the importance of his training as a scientist in his life as a writer.

Although a city dweller, Levi had a lifelong love of nature and an encyclopedic knowledge of plants, social behavior and mating habits with total absorption, as others might read a vast generational saga. In writing of the mating song of crickets, he notes how a slight change in temperature can wreck the courtship: “If the body heat of the female (or male) is increased by only two or three degrees, its song goes one semitone higher, and the partner no longer answers: He no longer recognizes in her (or in him) a possible sexual mate. From a minuscule environmental cause, an incompatibility is born. Don’t we have the germ of a novel here?”

Levi’s essays on frogs, spiders, crickets and tapeworms are reminiscent of biologist Stephen Jay Gould’s “Hens’ Teeth and Horses’ Toes.” Like Gould, Levi is in awe of the wildly imaginative adaptability of animal life. “The Leap of the Flea,” for example, is a veritable ode in praise of the parasite. “Among animals, it is precisely the parasites we should admire most for the originality of their intentions inscribed in their anatomy, their physiology, and their habits . . . think of the fleas on the rabbit, whose ovaries, thanks to a complicated play of hormonal messages, work in synchrony with the ovaries of the host. . . . Think of mosquitoes and vampire bats, which, though so different from each other, have invented anesthesia and use it in order not to disturb the sleep of the host during their modest removal of blood.”

Fortunately, Levi also describes himself and his own habitat with the same naturalist’s eye. “I have always lived (with involuntary interruptions) in the house where I was born,” he writes. “I represent an extreme case of the sedentary person, comparable to certain mollusks, limpets, for example, which, after a brief larval stage during which they swim about freely, attach themselves to sea rock, secrete an outer shell, and stay put for the rest of their lives.” In another essay (“Love’s Erector Set”), he describes his own youthful mating habits in telling the story of an unsuccessful attempt to woo a girl by building her a home-made clock.

Some of the essays dealing with animals have an autobiographical element, as well: “Frogs on the Moon” describes the long, childhood summers in the country during which, out of boredom, Levi began breeding tadpoles. Thus along with providing a number of charming examples of popular science, “Other People’s Trades” gives us occasional glimpses into Levi’s other life, his passing intellectual fancies and part-time hobbies. The autobiographical strain that runs through about 20 of the 43 pieces in the collection will likely interest readers who have discovered Levi through his various books of memoirs, “Survival at Auschwitz,” “The Reawakening” and “The Periodic Table.” However, a reader hoping to find in “Other People’s Trades” a continuation of those earlier works will be disappointed. The autobiographical sketches in this volume are light and fragmentary. But they are precious in affording us an unguarded view of Levi in everyday guise, as father, mediocre chess player, youthful athlete, novel reader, and struggling language student.

Although Levi retired in 1977 from his job at the paint factory in order to dedicate himself to writing full-time, he included literature as one of the professions in which he considered himself an amateur. “Other People’s Trades” therefore contains a couple of pieces of literary criticism and some of Levi’s only statements about his vocation as a writer. Curiously, these are some of the weaker pieces in the collection.

When called on to make pronouncements on abstract subjects, Levi has a tendency to be didactic and sententious. For example, in “On Obscure Writing,” he writes: “There is no doubt that the better the quality of our communication, the more useful (and agreeable) to ourselves and others we will be and the longer we will be remembered.” But there are few such false notes in this collection. Levi is generally drawn to concrete and simple things--a piece of wood or a paramecium--and transforms them into objects of wonder through his descriptive powers and his special autobiographical lens.