BOOK REVIEW: MEMOIR : A Sobering Look at Life Out in the Streets : TRAVELS WITH LIZBETH: Three Years on the Road and on the Streets <i> by Lars Eighner</i> ; St. Martin’s Press, $19.95, 271 pages

How to adequately describe “Travels With Lizbeth”? A bittersweet story of a boy and his dog? An urban “Swiss Family Robinson”?

An “Odyssey”-like adventure/quest tale in which ultimately, literally, there is no home? A how-to survival guide for those who don’t subscribe to the traditional goals and mores of American society?

The answer, oddly enough, is all of the above.

Lars Eighner, a sometime author of magazine stories, has crafted a consistently interesting, refreshingly unsentimental memoir that covers many hitchhiked miles and a period of several years.

As he and his mixed-breed dog, Lizbeth, twice traverse the southwestern United States from Austin, Tex., to Los Angeles, Eighner introduces us to arrogant health professionals, petty thieves, kindly alcoholics and various other fellow travelers.

Through the medium of his precise, often ironic prose, we share the experience of being broke and stranded for days at a rest stop in sidewalkless Tucson. We ride a roller coaster of chance and disappointment, hope and resignation. We reside in a seedy Hollywood rooming house, in a Texas bamboo wilderness, in a public park with only a piece of plastic for protection and privacy.

“It is a crime to be poor,” Eighner tells us. “It is a crime to sleep in a public place and a crime to trespass to sleep in a private place. But more than that, to be poor is to be subject entirely to the agents of the law.”

As a man without roots or anchor, Eighner is nothing if not inventive. He constantly improvises from the opportunities and materials immediately at hand, becoming an expert “dumpster diver” and a perceptive if not always wise judge of human nature at its most basic level.

He negotiates a meandering passage through a bizarre and danger-fraught gantlet, remaining almost always the cool observer, the dispassionate eye and ear, the eloquent voice of common sense.

“Most agencies, and especially their volunteers who do so much of the real work,” he writes, “want cuddly warm clients. In the case of AIDS, that means the volunteers are best prepared for people who will lie down and die quietly. Many people who apply to work with persons with AIDS envision themselves as ministering martyrs among the lepers. They imagine the work will involve many tender and touching moments as their patients struggle to express eternal gratitude before expiring gently.”

Time and again, Eighner sacrifices personal security or advancement for love.

True, the single emotional tie he refuses to sever or compromise is with the not-especially-bright Lizbeth. But affection is affection, and Eighner at every turn provides food and shelter to his dog before he doles it out to himself, as if offering living proof that an inherent psychological human need for companionship, loyalty and responsibility must be counted as equal among our biological requirements of food, water, warmth and sleep.

“Travels With Lizbeth” is a polished and surprisingly inviting memoir, displaying none of the fragmentation or artlessness normally found in a haphazard journal.

A writer who turns a reflective eye on his own life must turn himself into at least a semi-fictional character, the star of a re-imagined personal drama that fulfills the structural requirements of any story.

Choices must be made: where to begin and end, where to locate the points of tension, how to highlight significant turning points and climaxes. The chaos of daily existence--exacerbated in this case by the lack of a regular job or ordered routine--must be organized into sentences, paragraphs and chapters, then presented with the edited coherence of retrospect.

We are left, therefore, with the inescapable conclusion that if Eighner were able to live in the focused manner with which he writes, his situation could not help but stabilize and improve.

In other words, if he were in fact simply who he appears to be on the page, he probably wouldn’t be who he is in real life.

“I have heard psychiatrists say that anyone who is homeless is ipso facto a chronic schizophrenic unless there is some more evident diagnosis,” Eighner writes, rather archly.

“By one school of thought it is a form of mental illness to be so much at variance with the commonly accepted values of one’s society. . . . By the criteria of homelessness and deviance, I was no doubt mentally ill.

“But given my values I thought I was about as rational and consistent as anyone could claim to be. I was moody. But in my material situation I think it no wonder that I was sometimes depressed. The wonder was that much of the time I managed to buoy up my spirits.”

The wonder of “Travels With Lizbeth” is that by the time we finish the book, we not only care about Eighner’s well-being, but we genuinely wish him well.