As one of the lifesaving crew that successfully cared for Physty, the sperm whale that beached itself near Fire Island last month, Richard Ellis was easily the most seasoned and knowledgeble observer of whales. Watching him in the water next to the still cetacean, I was impressed with Ellis' touch. For long stretches, he would rub Physty's huge spout, then he would put his ear to the skin and press hard for the interior sounds of echolocation.

When Physty -- short for Physter macrocephelous -- was eased out to sea after nine days of antibiotics, vitamin shots and snout rubs, it was Ellis, in his red diving suit, who best understood that however immense this particular whale may have been, a greater immensity was present: the huge body of knowledge still to be discovered about all whales.

When I talked with Ellis a few days after the rescue of Physty, he said that because this event "was so unique, it was difficult to figure out what we should have been doing. It was like a creature landing from outer space, and you say, 'Wow, it's purple.' Do you ask it, 'Are all of you purple?' So we didn't know what questions to ask. In fact, nobody every measured Physty."

A fair amount of genuine humility is revealed in that statement. If anyone at the Fire Island boat basin, where this remarkable recovery occurred, was entitled to do a bit of hot-dogging as the resident whale expert, it was Ellis. He is the best known and perhaps hardest working marine artist now operating, traveling from Newfoundland to Hawaii to Patagonia to observe these leviathan wonders in motion. But at Fire Island he was on hand as a serious researcher, intent on inching ahead with the same sense of wonder that he brings to "The Book of Whales."

It is a thorough, well written and finely illustrated account of the creatures described by Hermann Melville as living in the "unshored, harborless immensities" of the deep. Ellis, who is a New Yorker and a member of the Explorers Club, offers as much for informed cetologist as for my ilk, the whale groupies who may trek 16 miles along the beach, as I did the other day, to see a gentle giant like Physty.

For the general reader, Ellis is the careful educator who wants to share his joy that "we are now caught up in a period of whale consciousness, as conservation groups the world over campaign to protect the great whales . . . We are on the threshold of an understanding of some of the world's most interesting creatures. But the secrets of cetaceans are not readily revealed, and we approach some species as if they were created to be captured and trained for our amusement. This attitude is as misguided as the one holding that whales were put on earth to provide us with cat food, margarine, and lipstick."

He discusses 33 whales, including the grays which are now heading north to the Bering Sea from the water of Baja California in what is the longest distance traveled by any migrating mammal; the seis, among the oceans' swiftest swimmers; the blues, the 80-footers that are reckoned to be larger and heavier than the biggest of the earth's dinosaurs; the humpbacks that were described in "Moby Dick" as "the most gamesome and lighthearted of all whales, making more gay foam and white water generally than any other of them."

Even after his exhaustive descriptions of these and less familiar kinds of whales, Ellis insists that all we know about them is that we know little: "Despite the learned papers and complicated formulas, our knowledge of the natural history of the great whales is still minimal, and most of our analyses of the behavior and biology of these great creatures are little more than fancy guesswork."

What Ellis doesn't guess about, and no one else needs to either, is man's distructiveness to whales. It is easy for Americans to denounce the Japanese as whale killers and boycott their products, but our fleets would still be roaming the oceans if whaling were the profitable industry it was once for us. We didn't stop for nobleness. Not long ago, at an internationa whaling conference, the U.S. delegation sided with the Soviet Union in objecting to a ban on the marketing of whale products.

Ellis was a U.S. delegate to the 1980 meeting of the International Whaling Commission, so he knows the shams of "regulation." He says the organization is "ostensibly dedicated to the preservation of whales in order that they might be harvested efficiently. In practice, however, the whaling nations seem intent on nothing less than destroying the resources on which their industry depends. But in recent years only the Soviets and the Japanese have continued to conduct pelagic whaling operations, resulting in what seem to be economic as well as political disasters for both countries. Despite massive reductions in stocks and worldwide condemnation, these countries have persisted in hunting the whales."

Richard Ellis continues to hunt them also -- with a camera. Seeing him at work at Fire Island, helping bring life back to Physty, was an uplifting experience for me. In this world of cowardly hunters, who kill on land and sea and wrap it with fake manliness, here was one citizen enhancing life. That be writes and paints well is a bonus.