The colossus at the end of your telephone line; The Biggest Company on Earth: A Profile of AT&T, by Sonny Kleinfield. New York: Holt, Rinehard & Winston. $14.95

Early in 1978 the New York Times ran the first of 19 articles by Sonny Kleinfield on the American Telephone & Telegraph Company. AT&T deserves such treatment because it is, almost any way one measures such things, the largest company in the world: It earns more money, owns more assets, employs more people , and is owned by more shareholders than any other company.

Now, Kleinfield has published a book based on those articles. The book provided the author an opportunity denied the series -- an opportunity to sum up and to provide some guidelines on the numerous policy issues surrounding this monstrous regulated monopoly. Unfortunately, Kleinfield let the opportunity slip away. The result is a book that is only occasionally more profound than an answer book for a telephone company trivia cult.

Maybe, just maybe, it is interesting to know that the Houston telephone directory, the nation's largest, contains 8,350 Smiths. But need we be told that the smallest directory has only 4 Smiths among the its 282 listings? Or that gophers inflict the most damage of any animal on telephone cable?

Daily events make this a timely book; more depth and a stronger point of view would have made it influential as well. William Baxter, chief of the Justice Department's Antitrust Division, wants to split AT&T into local phone companies, which would remain regulated, and companies selling long distance service and telecommunications equipment, which would be deregulated. "The Biggest Company on Earth" contains an information-laden chapter on each of these subjects: "On the Line" tells about one local company; "When You See Red, Get Yourself Moving" describes Bell's long-distance service; and "The Lint Requirement" covers Western Electric, the wholly owned company that AT&T keeps to manufacture, buy, and distribute "things" to the local companies that provide the "service." But these chapters fail to provide sufficient guidance to evaluate Baxter's proposal.

Not that the book lacks balance. It is balanced, but in the same mechanical way newspapers often balance their stories: add two paragraphs of opposition view to every 10- paragraph story and let cool. What this book lacks is depth. Chapter 8, for example, "Herding Elephants with Flyswatters," provides much information about the ratemaking process, but little exploration. The basic monthly charge for a residential phone in Los Angeles is $6; in Boston it is $10 .70. Why? Is the L.A. charge being subsidized by revenues from other Bell companies -- long distance, the Yellow Pages, Western electric, or even Boston's phone company? Is regulation more vigorous in L.A. than in Boston? Kleinfield mentions such possibilities: I want answers.

In places, the onslaught of information is presented with flare, as when the author talks about "the blue haze of phone company terminology," and the executive suites that are decorated in "warm shades of relentless good taste." And some chapters are ery effective. He successfully brings down to earth the often ethereal world of high finance in his chapter describing the bidding between the Morgan Stanley and First Boston syndicates for the right to market New York Telephone bonds.

And when he gets to "The Troops," his chapter about the employees, the book becomes exciting, dramatic, and human, as the Bell workers articulate their alienation at a furious pace. "As they put more and more equipment in, we become closer to button- pushers. The work is easier and cleaner, but it's less rewarding." And they provide clues to the inefficiency that everyone senses about the Bell System. "To do quality work, there is an unbelievable amount of bureaucracy to fight." "You like to be at a place where performance counts." Here, finally, are the blood and guts behind the black plastic box I turn to a dozen times a day.

Scattered throughout are several passages that left me feeling that Ma Bell was really Big Brother. Kleinfield describes as lunch with a security analyst that was down on AT&T. Later that day, the author received a call from the public relations people at AT&T offering to set up a meeting with an upbeat analyst. Kleinfield says he never discovered how AT&T had found out about that lunch.But I still wonder. Elsewhere, a worker says, "Knowing that somebody can clocking you at any time, checking out how you're doing, hardly makes for a sane environment." For me, there is a serious warning here; not so, apparently, for Kleinfield.

At the end of it all, we are left with the comment the author remembers best from all his interviews about the nature of the phone system. "The Bell System is like the sea . . . sometimes quiet and peaceful. . . . Other times it rages up and occasionally wreaks havoc. . . . We pollute it and we build barriers to it, but we can't live without it, and I'm not sure we can really control it. . . . No matter what else happens, though, it is always there." This is not poetry; it is mystification. AT&T is not the sea; AT&T is a human creation. So shouldn't we be able to understand and control it? If so, we will have to look elsewhere for guidan ce.