Since the advent of automatic bank tellers that greet customers by name with pleasant beeps and sprightly green letters, the concept of "talking" machines has developed rapidly.

The automatic teller's "Good morning Charles. Please select a transaction," appears on an electronic screen in front of the customer who, with little thought, punches back an answer to the machine's "personalized" request.

We are accustomed, in this electronic age, to conversing with the inanimate. In California, the latest fashin in tobmstones is one that talks back. For a substantial price, these monuments deliver solar-powered recorded messages from the deceased to anyone at graveside who cares to listen.

In life as in death, such vocal machinery is emerging in all sorts of unpredictable places. Otis Elevator Co. of Farmington, Conn., has installed about 100 talking elevators around the country. The new models threaten to revolutionize our proper American elevator etiquette that dictates, above all, eyes-offer a chatty vocabulary of 111 words in an inobtrusive, polite male voice. The elevator announces each floor as it arrives as well as the next planned stop after the doors close. It can be programmed to -- say, at appropriate floors, "mezzanine," "restaurant" or "bar," or, during an emergency, "Exit at the next floor." If someone obstructs the elevator doors, the same voice orders the perpetrator to clear out.

During their first trip in such an elevator, many passengers first look furtively around to see who is doing the talking, says Kevin Huntington, manager of architectural products for Otis. Once they realize that it is the elevator speaking and not Big Broterh, passengers break the code of silence long enought to chuckle with each other.

"It's a fairly foolproof system for the needs of the handicapped, particularly for the needs of the blind," says Huntington. "Right now many state and national codes require raised tactile buttons and tones to announce each floor," and the chatty elevator is another alternative.

Not yet perfected is another version that listens as well as talks. The voice-activated elevator, which recognizes only the voices of those authorized to enter the building, is one answer to security problems for residential developers. Anyone wishing to go upstairs in one of these elevators must literally speak up or stay grounded. "Many people would be too shy to use it effectively," admits Huntington.

Since our voices are as unique as our fingerprints, a smart elevator will search its memory banks to see if Mr. Smith is who he says he is. If the elevator, in its finite wisdom, deems that he is, Mr. Smith can go home.

"We don't think about our voices as much as scientists do," says Huntington. The voice-activated elevator now is on ly 80 percent accurate, and it must be 99.9 percent accurate before it can be installed.

The problems? "If the voice resolution is set high, and someone says 'heretofore,' the elevator will suddenly go to the fourth floor," says Huntington. Regional dialects and foreign accents may fail to budge the standard-English elevator.

Not the least of Otis' worries is that the elevator may fail to recognize a legitimate resident's voice, even after the inevitable shouts, whines and curses from the irate resident.

But such problems surely will be corrected, and the voice-responsive elevator will become as common as automatic telephone-answering machines.

But what of the future? Elevators will expand their meager 111-word vocabulary and will be better able to recognize regular riders.

Any modern elevator already knows how much you weigh when you step ever-so-lightly onto its carpeted floor, and Otis is designing an elevator that will recognize its passengers by body odor, or "natural fragrance," as Otis' designers prefer to say. It is not too far from the realm of possibility for a future elevator ride to be completely different from the silet ones of today.

"Good morning, Mr. Jones. Fourth floor as usual today?" a politely programmed elevator mght say after its sensing mechanisms have identified the rider.

Or: "Aw right, step to the rear. Which floor da ya want? And speak up, buddy."

When some unthinking lout steps onto the elevator before allowing passengers to step off, a well-trained elevator will say, "Let the others off first, please," and then perhaps add the catty aside, "How rude."

As the ubiquitous observer, the elevator of the future will be able to impart gossip, observe who arrives late for work, who leaves early and who takes a long lunch.

We might be better off taking the stairs.