WHEN temperatures hover at 90 degrees and the cicadas drone in the torpid air and the green maple leaves seem to gasp against a hazy blue Kentucky sky, I begin to think of the beach. It doesn't matter that we live landlocked and that finding the nearest ocean would mean driving about 14 hours straight.After growing up in North Miami Beach, close enough to the ocean to smell the salt wafting through the air on windy days, only plunging into the frothy waves of the Atlantic can satisfy this longing. The Ohio River is nearby, but seeing Indiana on the other side deprives me of the reassurance that a kind of endlessness exists. Looking out into the infinite expanse of ocean gives heart to the weary and lifts the spirits of those feeling trapped by dull routine. When I was a child, going to the beach was simple: Put on a bathing suit, slip into rubber thongs, and find an obliging parent to drive 10 minutes to Haulover Beach. Once there, my friends and I would hit the pavement of the parking lot and dash headlong toward the water. The tunnel underneath the road between the parking lot and the beach would fill with the echoes of our shouts. After the tunnel's cool darkness, we'd emerge onto the brightness of the beach. The hot sand blistered our bare feet once we'd kicked off our thongs, but that only made us race faster toward the waiting coolness. As we ran, we always noticed the color of the water that day and, more importantly, what the waves were doing. Most days the water was aquamarine, deepening to blue farther out. Sometimes, we would note the shades of darker blue that mixed with blue-green and pure green when storms were threatening. The waves varied too. We always hoped for high ones that would carry us like human surfboards back to shore then pull us into the curl until we were ground into the rough sand and came up sputtering. Once in the water, we ventured out up to our necks. We always knew how far to go. We knew that the jellyfish that floated into shore came from where the blue-black deepness was full of sharks and stingrays and where live conchs, their shells unmarked by pounding surf, would graze the underground meadows of the sea. I always wished that, for just one hour, the ocean would recede, and we could walk out to where treasures lay and where all of the ocean's mysteries would be revealed. Just once, I wanted to w alk straight toward the horizon across those underwater hills and valleys and through bright coral forests that I had never seen. Instead, we spent hours combing the shoreline in foot-deep water, looking for the perfect shell. Sometimes, we spied schools of silver minnows, a shiny needlefish, or floating driftwood, all hints of what was out there beyond our reach. For those hours at the beach we were held in the uncomplicated space between the sky and the far-off horizon and the sand we walked upon. Entranced, we never realized that reverence would not always be a given fact of life. I also never expected that there would come years when the ocean and I would no longer be regular companions. Grown up, I moved away and only visited infrequently. Not too long ago, however, after living for 13 years far from Miami and its beach, I had the chance to spend a week on its shore. My family and I stayed in a small motel that was dwarfed by surrounding condominiums. For seven days, we would eat and sleep and be at home alongside the ocean I had loved. Nevertheless, as I sat on my beach towel and watched my children discover waves and sand and seaweed, I found myself distracted by thoughts of the crowded beachfront, of sewage constantly pumping, and of washed-up plastic flotsam and globs of tar that stuck to our feet. The sun itself, in its brightness, seemed menacing, so I went inside to escape the encroaching blemishes that seemed to mar my remembered landscape. Even my beach had not escaped the worst tendencies of our present day and the less desira ble consequences of economic growth. ON the third night of our stay, we returned late from a restaurant in the city and decided to walk out to where the waves lapped gently under a bright moon. Further down the beach we suddenly noticed a dark shape emerging from the sea. For a moment, terrified, I expected some science-fiction apparition to appear or a late swimmer pursued by sharks. But then, as the full form slowly emerged onto the sand, we realized what it was: a sea turtle, large and bulky, lumbering slowly, doggedly through the sand. Motionless, we watched while the turtle, a mother, driven by ageless instinct, searched for the foreknown spot, unaware or unconcerned by us. Feeling too excited to hoard the sight, I ran to a group of Cubans chatting softly on the motel's patio and beckoned to them. Six of us stood silently on the empty beach while the lights of Miami illumined the errand of this gentle creature from the deep. She dug with persistence for 10 minutes until she had excavated a 2-foot-deep trench. We watched as eight white eggs, her progeny, dropped like large pearls gently into the hole. When she had finished, her flipper feet swept the sand back into the hole, covering her treasure. After that, her task completed, she turned back toward the sea, trusting that nature would fulfil its promise of continuity. WE followed her slow progress and then, no longer afraid of interfering, one by one we reached down to touch her great domed back, as if to confirm the vision we had seen. Slowly, she slipped once more into the warm waters and disappeared out toward the depths. I stood staring out for a long time, sad to see her go, yet heady with the thought of having touched such undomesticated wildness here on my familiar beach, here on the very doorstep of a modern metropolis. Later, we marked the spot where the eggs lay buried and went to call the turtle hotline. Early the next morning, before the sand-smoothing tractors, the sunbathers, and the plastic shovels arrived to reclaim the beach, several wildlife rangers came and carefully dug up the eggs. They would transport them to the safe haven of a nature refuge. The noble sight of this human rescue gave me distinct hope and helped uncloud my earlier dismay. I decided to join my daughters when they went snorkeling that day. The shallow waters where we swam dazzled beneath the surface as we inspected handfuls of shells and coral rock. All the time that we spent reveling in the turtle's territory seemed heightened by the previous night's encounter. I realized that the turtle in her trust and enduring instinct had restored the ocean's gift to me and had renewed my faith in the persistence of Earth's timeless rhythms. And yet I knew that the sea turtle and her kind are not assured a safe passage through the present dangers into the next century. I wondered if my girls, when grown, would be seeing a turtle on this beach. Back in Kentucky, another summer has begun. Longing for the beach, I like to think of that endless blue expanse and a lone turtle swimming steadily toward the shore.