Under the Sea Wind, 1941

The Sea Around Us, 1950

The Edge of The Sea, 1955

Silent Spring, 1962

The Sense of Wonder, 1956

When we go down to the low-tide line, we enter a world that is as old as the Earth itself – the primeval meeting place of the elements of earth and water, a place of compromise and conflict and eternal change.
- Rachael Carson, The Edge of the Sea

Under the Sea-Wind

The pond slept in noonday quiet. Against the green of the marsh grass the heron was a snow-white figure on slim black stilts, tense and motionless. Not a ripple nor the shadow of a ripple passed beneath his sharp eyes. Then eight pale minnows swam single file above the muddy bottom, and eight black shadows moved beneath them.

            With snakelike contortion of its neck, the heron jabbed violently, but missed the leader of the solemn little parade of fish. The minnows scattered in sudden panic as the clear water was churned to muddy chaos by the feet of the heron, who darted one way and another, skipping and flapping his wings in excitement. In spite of his efforts, he captured only one of the minnows.

            The heron had been fishing for an hour and the sanderlings, sandpipers, and plovers had been sleeping for three hours when a boat's bottom grated on the sound beach near the point. Two men jumped out into the water and made ready to drag a haul seine through the shallows on the rising tide. The heron lifted his head and listened. Through the fringe of sea oats on the sound side of the pond he saw a man walking down the beach toward the inlet. Alarmed, he thrust his feet hard against the mud and with a flapping of wings took off over the dunes to­ward the heron rookery in the cedar thickets a mile away. Some of the shore birds ran twittering across the beach toward the sea. Already the terns were milling about overhead in a noisy cloud, like hundreds of scraps of paper flung to the wind. The sanderlings took flight and crossed the point, wheeling and turning almost as one bird, and passed down the ocean beach about a mile.

            The ghost crab, still at his hunting of beach fleas, was alarmed by the turmoil of birds overhead, by the many racing shadows that sped over the sand. By now he was far from his own burrow. When he saw the fisherman walking across the beach he dashed into the surf, preferring this refuge to flight. But a large channel bass was lurking near by, and in a twin­kling the crab was seized and eaten. Later in the same day, the bass was attacked by sharks and what was left of it was cast up by the tide onto the sand. There the beach fleas, scavengers of the shore, swarmed over it and devoured it.

            Below them lay the abyss, the Primeval bed of the sea, the deepest of all the Atlantic. The abyss is a place where change comes slow, where the passing of the years has no meaning, nor the swift succession of the seasons. The sun has no power in those depths, and so their blackness is a blackness without end, or beginning, or degree. No beating of tropical sun on the surface miles above can lesson the bleak iciness of those abyssal waters that varies little through summer or winter, through the years that melt into centuries, and the centuries into ages of geologic time. Along the floor of the ocean basins, the currents are a slow creep of frigid water, deliberate and inexorable as the flow of time itself.

            Down beneath mile after mile of water -- more than four miles in all --lay the sea bottom, covered with a soft, deep ooze that had been accumulating there through eons upon eons of time. These greatest depths of the Atlantic are carpeted with red clay, a pumice-like deposit hurled out of the earth from time to time by submarine volcanoes. Mingled with the pumice are spherules of iron and nickel that had their origin on some far-off sun and once rushed millions of miles through interstellar space, to perish in the earth's atmosphere and find their grave in the deep sea. Far up on the sides of the great bowl of the Atlantic the bottom oozes are thick with the skeletal remains of minute sea creatures of the surface waters -- the shells of starry Foraminifera and the limy remains of algae and corals, the flint-like skeletons of Radiolaria and the frustules of diatoms. But long before such delicate structures reach this deepest bed of the abyss, they are dissolved and made one with the sea. Almost the only organic remains that have not passed into solution before they reach these cold and silent deeps are the ear bones of whales and the teeth of sharks. Here in the red clay, in the darkness and stillness, lies all that remains of ancient races of sharks that lived, perhaps, before there were whales in the sea; before the giant ferns flourished on the earth or even the coal measures were laid down. All of the living flesh of these sharks was returned to the sea millions of years before, to be used over and over again in the fashion­ing of other creatures, but here and there a tooth still lies in the red-clay ooze of the deep sea, coated with a deposit of iron from a distant sun.

            The abyss south of Bermuda is a meeting place for the eels of the western and eastern Atlantic. There are other great deeps in the ocean between Europe and America -- chasms sunk between the mountain ranges of the sea's floor -- but only this one is both deep enough and warm enough to provide the condi­tions which the eels need for the act of spawning. So once a year the mature eels of Europe set out across the ocean on a journey of three to four thousand miles; and once a year the mature eels of eastern America go out as though to meet them. In the westernmost part of the drifting sea of sargassum weed some of them meet and intermingle -- those that travel farthest west from Europe and farthest east from America. So in the central part of the vast spawning grounds of the eels, the eggs and young of two species float side by side in the water. They are so alike in appearance that only by counting with infinite care the vertebrae that make up their backbones and the plates of muscle that flank their spines can they be distinguished. Yet some, toward the end of their period of larval life, seek the coast of America and others the coast of Europe, and none ever stray to the wrong continent.

The Sea Around Us

Meanwhile, the gradual cooling of the planet, which had first given the earth its hard granite crust, was progressing into its deeper layers; and as the interior slowly cooled and contracted, it drew away from the outer shell. This shell, accommodating itself to the shrinking sphere within it, fell into folds and wrinkles -- the earth's first mountain ranges.

           When they went ashore the animals that took up a land life carried with them a part of the sea in their bodies, a heritage which they passed on to their children and which even today links each land animal with its origin in the ancient sea. Fish, amphibian, and reptile, warm-blooded bird and mammal--each of us carries in our veins a salty stream in which the elements sodium, potassium, and calcium are combined in almost the same proportions as in sea water. This is our inheritance from the day, untold millions of years ago, when a remote ancestor, having progressed from the one-celled to the many-celled stage, first developed a circulatory system in which the fluid was merely the water of the sea. In the same way, our lime-hardened skeletons are a heritage from the calcium-rich ocean of Cambrian time. Even the protoplasm that streams within each cell of our bodies has the chemical structure impressed upon all living matter when the first simple creatures were brought forth in the ancient sea. And as life itself began in the sea, so each of us begins his individual life in a miniature ocean within his mother's womb, and in the stages of his embryonic development repeats the steps by which his race evolved, from gill-breathing inhabitants of a water world to creatures able to live on land. 

            The existence of an abundant deep-sea fauna was discovered, probably millions of years ago, by certain whales and also, it now appears, by seals. The ancestors of all whales, we know by fossil remains, were land mammals. They must have been preda­tory beasts, if we are to judge by their powerful jaws and teeth. Perhaps in their foragings about the deltas of great rivers or around the edges of shallow seas, they discovered the abundance of fish and other marine life and over the centuries formed the habit of following them farther and farther into the sea. Little by little their bodies took on a form more suitable for aquatic life; their hind limbs were reduced to rudiments, which may be discovered in a modern whale by dissection, and the forelimbs were modified into organs for steering and balancing.

            Eventually the whales, as though to divide the sea's food resources among them, became separated into three groups: the plankton-eaters, the fish-eaters, and the squid-eaters. The plank­ton-eating whales can exist only where there are dense masses of small shrimp or copepods to supply their enormous food re­quirements. This limits them, except for scattered areas, to arctic and ant-arctic waters and the high temperate latitudes. Fish-eat­ing whales may find food over a somewhat wider range of ocean, but they are restricted to places where there are enormous pop­ulations of schooling fish. The blue water of the tropics and of the open ocean basins offers little to either of these groups. But that immense, square-headed, formidably toothed whale known as the cachalot or sperm whale discovered long ago what men have known for only a short time -- that hundreds of fathoms be­low the almost untenanted surface waters of these regions there is an abundant animal life. The sperm whale' has taken these deep waters for his hunting grounds; his quarry is the deep-water population of squids, including the giant squid Architeu­this, which lives pelagically at depths of 1500 feet or more. The head of the sperm whale is often marked with long stripes, which consist of a great number of circular scars made by the suckers of the squid. From this evidence we can imagine the battles that go on, in the darkness of the deep water, between these two huge creatures-the sperm whale with its 70 ton bulk, the squid with a body as long as 80 feet, and writhing, grasping arms ex­tending the total length of the animal to perhaps 50 feet.

   On the Atlantic coast of the United States, the 97-foot tower on Minot's Ledge is often completely enveloped by masses of water from breaking surf, and an earlier light on this ledge was swept away in 1851. Then there is the often quoted story of the December storm at Trinidad Head Light on the coast of Oregon. As the keeper watched the storm from his lantern 196 feet above high water, he could see the near-by Pilot Rock engulfed again and again by waves that swept over its hundred-foot crest. Then a wave, larger than the rest, struck the cliffs at the base of the light. It seemed to rise in a solid wall of water to the level of the lantern, and it hurled its spray completely over the tower. The shock of the blow stopped the revolving of the light.

   Along a rocky coast, the waves of a severe storm are likely to be armed with stones and rock fragments, which greatly in­crease their destructive power. Once a rock weighing 135 pounds was hurled high above the lightkeeper's house on Tillamook Rock, 100 feet above sea level. In falling, it tore a 20-foot hole through the roof. The same day showers of smaller rocks broke many panes of glass in the lantern, 132 feet above the sea. The most amazing of such stories concerns the lighthouse at Dunnet Head, which stands on the summit of a 300-foot cliff at the south­western entrance to Pentland Firth. The windows of this light have been broken repeatedly by stones swept from the cliff and tossed aloft by waves....

   In the open ocean the waves produced by the Aleutian quake were only about a foot or two high and would not be noticed from vessels. Their length, however, was enormous, with a distance of about 90 miles between succeeding crests. It took the waves less than 5 hours to reach the Hawaiian chain, 2300 miles distant, so thy must have moved at an average speed of about 470 miles per hour. Along eastern Pacific shores, they were re­corded as far into the Southern Hemisphere as Valparaiso, Chile, the distance of 8066 miles from the epicenter being covered by the waves in about 18 hours.

   Since the world began, the ocean currents have undoubtedly changed their courses many times (we know, for example, that the Gulf Stream is no more than about 60 million years old); but it would be a bold writer who would try to describe their pattern in the Cambrian Period, for example, or in the Devonian, or in the Jurassic. So far as the brief period of human history is con­cerned, however, it is most unlikely that there has been any im­portant change in the major patterns of oceanic circulation, and the first thing that impresses us about the currents is their per­manence. This is not surprising, for the forces that produce the currents show little disposition to change materially over the eons of earthly time. The primary driving power is supplied by the winds; the modifying influences are the sun, the revolving of the earth ever toward the east, and the obstructing masses of the con­tinents....

   Now we give the matter little thought, but in the days of sail, passage out into the Atlantic was a difficult problem because of this surface current. An old ship's log of the year 1855 has this to say of the current and its practical effect:

 'Weather fine; made 1 1/4 pt. leeway. At noon, stood in to Almira Bay, and anchored off the village of Roguetas. Found a great number of vessels waiting for a chance to get to the westward, and learned from them that at least a thousand sail are weather­bound between this and Gibraltar. Some of them have been so for six weeks, and have even got so far as Malaga, only to be swept back by the current. Indeed, no vessel has been able to get out into the Atlantic for three months past.'

    There is, then, no water that is wholly of the Pacific, or wholly of the Atlantic, or of the Indian or the Antarctic. The surf that we find exhilarating at Virginia Beach or at La Jolla today may have lapped at the base of antarctic icebergs or sparkled in the Medi­terranean sun, years ago, before it moved through dark and un­seen waterways to the place we find it now. It is by the deep, hidden currents that the oceans are made one.

   There is no drop of water in the ocean, not even in the deepest parts of the abyss, that does not know and respond to the mys­terious forces that create the tide. No other force that affects the sea is so strong. Compared with the tide the wind-created waves are surface movements felt, at most, no more than a hundred fathoms below the surface. So, despite their impressive sweep, are the planetary currents, which seldom involve more than the upper several hundred fathoms. The masses of water affected by the tidal movement are enormous, as will be clear from one ex­ample. Into one small bay on the east coast of North America -- Passamaquoddy -- two billion tons of water are carried by the tidal currents twice each day; into the whole Bay of Fundy, a hundred bil­lion tons....

   The tides are a response of the mobile waters of the ocean to the pull of the moon and the more distant sun. In theory, there is a gravitational attraction between every drop of sea water and even the outermost star of the universe. In practice, however, the pull of the remote stars is so slight as to be obliterated in the vaster movements by which the ocean yields to the moon and the sun. Anyone who has lived near tidewater knows that the moon, far more than the sun, controls the tides. He has noticed that, just as the moon rises later each day by fifty minutes, on the average, than the day before, so, in most places, the time of high tide is correspondingly later each day. And as the moon waxes and wanes in its monthly cycle, so the height of the tide varies. Twice each month, when the moon is a mere thread of silver in the sky, and again when it is full, we have the highest of the high tides, called the springs. At these times sun, moon, and earth are di­rectly in line and the pull of the two heavenly bodies is added together to bring the water high on the beaches, and send its surf leaping upward against the sea cliffs, and draw a brimming tide into the harbors so that the boats float high beside their wharfs. And twice each month, at the quarters of the moon, when sun, moon, and earth lie at the apexes of a triangle, and the pull of sun and moon are opposed, we have the least tides of the lunar month, called the neaps.

   That the sun, with a mass 27 million times that of the moon, should have less influence over the tides than a small satellite of the earth is at first surprising. But in the mechanics of the uni­verse, nearness counts for more than distant mass, and when all the mathematical calculations have been made, we find that the moon's power over the tides is more than twice that of the sun.

...In Europe it has been well established that the spawning activities of oysters reach their peak on the spring tides, which are about two days after the full or the new moon. In the waters of northern Africa there is a sea urchin that, on the nights when the moon is full and apparently only then, releases its reproductive cells into the sea. And in tropical waters in many parts of the world there are small marine worms whose spawn­ing behavior is so precisely adjusted to the tidal calendar that, merely from observing them, one could tell the month, the day, and often the time of day as well.

      Near Samoa in the Pacific, the pablo worm lives out its life on the bottom of the shallow sea, in holes in the rocks and among the masses of corals. Twice each year, during the neap tides of the moon's last quarter in October and November, the worms for­sake their burrows and rise to the surface in swarms that cover the water. For this purpose, each worm has literally broken its body in two, half to remain in its rocky tunnel, half to carry the reproductive products to the surface and there to liberate the cells. This happens at dawn on the day before the moon reaches its last quarter, and again on the following day; on the second day of the spawning the quantity of eggs liberated is so great that the sea is discolored....

      Shortly after the full moon of the months from March to Au­gust, the grunion appear in the surf on the beaches of California. The tide reaches flood stage, slackens, hesitates, and begins to ebb. Now on these waves of the ebbing tide the fish begin to come in. Their bodies shimmer in the light of the moon as they are borne up the beach on the crest of a wave, they lie glittering on the wet sand for a perceptible moment of time, then fling themselves into the wash of the next wave and are carried back to sea. For about an hour after the turn of the tide this continues,

thousands upon thousands of grunion coming up onto the beach, leaving the water, returning to it. This is the spawning act of the species.

      During the brief interval between successive waves, the male and female have come together in the wet sand, the one to shed her eggs, the other to fertilize them. When the parent fish return to the water, they have left behind a mass of eggs buried in the sand. Succeeding waves on that night do not wash out the eggs because the tide is already ebbing. The waves of the next high tide will not reach them, because for a time after the full of the moon each tide will halt its advance a little lower on the beach than the preceding one. The eggs, then, will be undisturbed for at least a fortnight. In the warm, damp, incubating sand they un­dergo their development. Within two weeks the magic change from fertilized egg to larval fishlet is completed, the perfectly formed little grunion still confined within the membranes of the egg, still buried in the sand, waiting for release. With the tides of the new moon it comes. Their waves wash over the places where the little masses of the grunion eggs were buried, the swirl and rush of the surf stirring the sand deeply. As the sand is washed away, and the eggs feel the touch of the cool sea water, the mem­branes rupture, the fishlets hatch, and the waves that released them bear them away to the sea.

      What I find most unforgettable about Convoluta is this: some­tirnes it happens that a marine biologist, wishing to study some related problem, will transfer a whole colony of the worms into the laboratory, there to establish them in an aquarium, where there are no tides. But twice each day Convoluta rises out of the sand on the bottom of the aquarium, into the light of the sun. And twice each day it sinks again into the sand. Without a brain, or what we would call a memory, or even any very clear perception, Convoluta continues to live out its life in this alien place, remembering, in every fiber of its small green body, the tidal rhythm of the distant sea.

      For the globe as a whole, the ocean is one great regulator, great stabilizer of temperatures. It has been described as 'a savings bank for solar energy, receiving deposits in seasons of ex­cessive insolation and paying them back in seasons of want.' Without the ocean, our world would be visited by unthinkably harsh extremes of temperature. For the water that covers three-forths of the earth's surface with an enveloping mantle is a substance of remarkable qualities. It is an excellent absorber and radiator of heat. Because of its enormous heat capacity, the ocean can absorb a great deal of heat from the sun without becoming what we would consider 'hot,' or it can lose mouch of its heat without becoming 'cold.'

 [A distinguished Swedish oceanographer, Otto Pettersson studied, among many other mysteries of the oceans] the changing fortunes of the Swedish herring fishery. His native Bohuslan had been the site of the great Hanseatic herring fisheries of the Middle Ages. All through the thirteenth, fourteenth, and fifteenth centuries this great sea fish­ery was pursued in the Sund and the Belts, the narrow passage-ways into the Baltic. The towns of Skanor and Falsterbo knew unheard-of prosperity, for there seemed no end of the silvery, wealth-bringing fish. Then suddenly the fishery ceased, for the herring withdrew into the North Sea and came no more into the gateways of the, Baltic -- this to the enrichment of Holland and the impoverishment of Sweden. Why did the herring cease to come? Pettersson thought he knew, and the reason was intimately related to that moving pen in his laboratory, the pen that traced on a revolving drum the movements of the submarine waves far down in the depths of Gulmarfiord.

          He had found that the submarine waves varied in height and power as the tide-producing power of the moon and sun varied. From astronomical calculations he learned that the tides must have been at their greatest strength during the closing centuries of the Middle Ages -- those centuries when the Baltic herring fish­ery was flourishing. Then sun, moon, and earth came into such a position at the time of the winter solstice that they exerted the greatest possible attracting force upon the sea. Only about every eighteen centuries do the heavenly bodies assume this particular relation. But in that period of the Middle Ages, the great under­water waves pressed with unusual force into the narrow passages to the Baltic, and with the 'water mountains' went the herring shoals. Later, when the tides became weaker, the herring re­mained outside the Baltic, in the North Sea....

During the latest period of benevolent climate, snow and ice were little known on the coast of Europe and in the seas about Iceland and Greenland. Then the Vikings sailed freely over northern seas, monks went back and forth between Ireland and “Thyle” or Iceland, and there was easy intercourse between Great Britain and the Scandinavian countries.When Eric the Red voyaged to Greenland, according to the Sagas, he 'came from the sea to land at the middle glacier -- from thence he went south along the coast to see if the land was habitable. The first year he wintered on Erik's Island. . .' This was probably in the year 984. There is no mention in the Sagas that Eric was hampered by drift ice in the several years of his exploration of the island; nor is there men­tion of drift ice anywhere about Greenland, or between Greenland and Wineland. Eric's route as described in the Sagas -- pro­ceeding directly west from Iceland and then down the east coast of Greenland -- is one that would have been impossible during recent centuries. In the thirteenth century the Sagas contain for the first time a warning that those who sail for Greenland should not make the coast too directly west of Iceland on account of the ice in the sea, but no new route is then recommended. At the end of the fourteenth century, however, the old sailing route was abandoned and new sailing directions were given for a more southwesterly course that would avoid the ice.

                                                         The early Sagas spoke, too, of the abundant fruit of excellent quality growing in Greenland, and of the number of cattle that could be pastured there. The Norwegian settlements were located in places that are now at the foot of glaciers. There are Eskimo legends of old houses and churches buried under the ice. The Danish Archaeological Expedition sent out by the National Mu­seum of Copenhagen was never able to find all of the villages mentioned in the old records. But its excavations indicated clearly that the colonists lived in a climate definitely milder than the present one.

But these bland climatic conditions began to deteriorate in the thirteenth century. The Eskimos began to make troublesome raids, perhaps because their northern sealing grounds were frozen over and they were hungry. They attacked the western settle­ment near the present Ameralik Fiord, and when an official mission went out from the eastern colony about 1342, not a single colonist could be found -- only a few cattle remained. The eastern settlement was wiped out some time after 1418 and the houses and churches destroyed by fire. Perhaps the fate of the Green­land colonies was in part due to the fact that ships from Iceland and Europe were finding it increasingly difficult to reach Green­land, and the colonists had to be left to their own resources.

       The climatic rigors experienced in Greenland in the thirteenth and fourteenth centuries were felt also in Europe in a series of unusual events and extraordinary catastrophes. The seacoast of Holland was devastated by storm floods. Old Icelandic records say that, in the winters of the early 1300's, packs of wolves crossed on the ice from Norway to Denmark. The entire Baltic froze over, forming a bridge of solid ice between Sweden and the Danish islands. Pedestrians and carriages crossed the frozen sea and hos­telries were put up on the ice to accommodate them. The freezing of the Baltic seems to have shifted the course of storms originat­ing in the low pressure belt south of Iceland. In southern Europe, as a result, there were unusual storms, crop failures, famine, and distress. Icelandic literature abounds in tales of volcanic eruptions and other violent natural catastrophes that occurred during the fourteenth century.

The Edge of the Sea

The shore is an ancient world, for as long as there has been an earth and sea there has been this place of the meeting of land and water. Yet it is a world that keeps alive the sense of continuing creation and of the relentless drive of life. Each time that I enter it, I gain some new awareness of its beauty and its deeper meanings, sensing that intricate fabric of life by which one creature is linked with another, and each with its surroundings.

       On a shore where tidal action is strong and the range of the tide is great, one is aware of the ebb and flow of water with a daily, hourly awareness. Each recurrent high tide is a dramatic enactment of the advance of the sea against the con­tinents, pressing up to the very threshold of the land, while the ebbs expose to view a strange and unfamiliar world. Per­haps it is a broad mud flat where curious holes, mounds, or tracks give evidence of a hidden life alien to the land; or per­haps it is a meadow of rockweeds lying prostrate and sodden now that the sea has left them, spreading a protective cloak over all the animal life beneath them. Even more directly the tides address the sense of hearing, speaking a language of their own distinct from the voice of the surf. The sound of a rising tide is heard most clearly on shores removed from the swell of the open ocean. In the stillness of night the strong waveless surge of a rising tide creates a confused tumult of water sounds -- swashings and swirlings and a continuous slapping against the rocky rim of the land. Sometimes there are under­tones of murmurings and whisperings; then suddenly all lesser sounds are obliterated by a torrential inpouring of water.

        On such a shore the tides shape the nature and behavior of life. Their rise and fall give every creature that lives between the high- and low-water lines a twice-daily experience of land life. For those that live near the low-tide line the exposure to sun and air is brief; for those higher on the shore the interval in an alien environment is more prolonged and demands greater powers of endurance. But in all the intertidal area the pulse of life is adjusted to the rhythm of the tides. In a world that belongs alternately to sea and land, marine animals, breathing oxygen dissolved in sea water, must find ways of keep­ing moist; the few air breathers who have crossed the high-tide line from the land must protect themselves from drowning in the flood tide by bringing with them their own supply of oxygen. When the tide is low there is little or no food for most inter-tidal animals, and indeed the essential processes of life usually have to be carried on while water covers the shore. The tidal rhythm is therefore reflected in a biological rhythm of alternating activity and quiescence.

        All through the lunar month, as the moon waxes and wanes, so the moon-drawn tides increase or decline in strength and the lines of high and low water shift from day to day. After the full moon, and again after the new moon, the forces acting on the sea to produce the tide are stronger than at any other time during the month. This is because the sun and moon then are directly in line with the earth and their attractive forces are added together. For complex astronomical reasons, the greatest tidal effect is exerted over a period of several days immediately after the full and the new moon, rather than at a time precisely coinciding with these lunar phases. During these periods the flood tiedes rise higher and the ebb tides fall lower than at any other time. These are called the "spring tides" from the Saxon "sprungen." The word refers not to a season, but to the brimming fullness of the water causing it to "spring" in the sense of a strong, active movement. No one who has watched a new-moon tide pressing against a rocky cliff will doubt the appropriateness of the term.

       The periwinkles grazing on the intertidal rocks, waiting for the return of the tide, are poised also in time, waiting for the moment when they can complete their present phase of evolu­tion and move forward onto the land. All snails that are now terrestrial came of marine ancestry, their forebears having at some time made the transitional crossing of the shore. The periwinkles now are in mid-passage. In the structure and habits of the three species found on the New England coast, one can see clearly the evolutionary stages by which a marine creature is transformed into a land dweller. The smooth periwinkle, still bound to the sea, can endure only brief exposure. At low tide it remains in wet seaweeds. The common periwinkle often lives where it is submerged only briefly at high tide. It still sheds eggs into the sea and so is not ready for land life. The rough peri­winkle, however, has cut most of the ties that confine it to the sea; it is now almost a land animal. By becoming viviparous it has progressed beyond dependence on the sea for reproduction. It is able to thrive at the level of the high water of the spring tides because, unlike the related periwinkles of lower tidal levels, it possesses a gill cavity that is well supplied with blood vessels and functions almost as a lung to breathe oxygen from the air. Con­stant submersion is, in fact, fatal to it and at the present stage of its evolution It can endure up to thirty-one days of exposure to dry air.

           The rough periwinkle has been found by a French experi­menter to have the rhythm of the tides deeply impressed upon its behavior patterns, so that it  "remembers" even when no longer exposed to the alternating rise and fall of the water. It Is most active during the fortnightly visits of the spring tides to its rocks, but in the waterless intervals it becomes progressively more sluggish and its tissues undergo a certain desiccation. With the return of the spring tides the cycle is reversed. When taken into a laboratory the snails for many months reflect in their behavior the advance and retreat of the sea over their native shores.

           During many days of midsummer, the incoming tides bring the round opalescent forms of the moon jellies. Most of these are in the weakened condition that accompanies the fulfillment of their life cycle; their tissues are easily torn by the slightest turbulence of water, and when the tide carries them in over the rockweeds and then withdraws, leaving them there like crumpled cellophane, they seldom survive the tidal interval. Each year they come, sometimes only a few at a time, some­times in immense numbers. Drifting shoreward, their silent approach is unheralded even by the cries of sea birds, who have no interest in the jellyfish as food, for their tissues are largely water.

           During much of the summer they have been drifting offshore, white gleams in the water, sometimes assembling in hundreds along the line of meeting of two currents, where they trace winding lines in the sea along these otherwise invisible bound­aries. But toward autumn, nearing the end of life, the moon jellies offer no resistance to the tidal currents, and almost every flood tide brings them in to the shore. At this season the adults are carrying the developing larvae, holding them in the flaps of tissue that hang from the under surface of the disc. The young are little pear-shaped creatures; when finally they are shaken loose from the parent (or freed by the stranding of the parent on the shore), they swim about in the shallow water, sometimes swarms of them together. Finally they seek bottom and each becomes attached by the end that was foremost when it swam. As a tiny plantlike growth, about an eighth of an inch high and bearing long tentacles, this strange child of the delicate moon jelly survives the winter storms. Then constrictions begin to encircle its body, so that it comes to resemble a pile of saucers. In the spring these "saucers" free themselves one after another and swim away, each a tiny jellyfish, fulfilling the alternation of the generations. North of Cape Cod these young grow to their full diameter of six to ten inches by July; they mature and produce eggs and sperm cells by late July or August; and in August and September they begin to yield the larvae that will become the attached generation. By the end of October all of the season's jellyfish have been destroyed by storms, but their off­spring survive, attached to the rocks near the low-tide line or on nearby bottoms offshore.

            The ghost crab, pale as the dry sand of the upper beaches it inhabits, seems almost a land animal. Often its deep holes are back where the dunes begin to rise from the beach. Yet it is not an air-breather; it carries with it a bit of the sea in the branchial chamber surrounding its gills, and at intervals must visit the sea to replenish the water. And there is another, almost symbolic return. Each of these crabs began its individual life as a tiny creature of the plankton; after maturity and in the spawning season, each female enters the sea again to liberate her young.

           If it were not for these necessities, the lives of the adult crabs would be almost those of true land animals. But at intervals during each day they must go down to the water line to wet their gills, accomplishing their purpose with the least possible contact with the sea. Instead of wading directly into the water, they take up a position a little above the place where, at the moment, most of the waves are breaking on the beach. They stand side­ways to the water, gripping the sand with the legs on the land­ward side. Human bathers know that in any surf an occasional wave will tower higher than the others and run farther up the beach. The crabs wait, as if they also know this, and after such a wave has washed over them, they return to the upper beach.

           A whole fleet of Portuguese men-of-war is sometimes seen from vessels crossing the Gulf Stream when some peculiarity of the wind and current pattern has brought together a number of them. Then one can sail for hours or days with always some of the siphonophers in sight. With the float or sail set diagonally across its base, the creature sails before the wind; looking down into the clear water one can see the tentacles trailing far below the boat. The Portuguese man-of-war is like a samll fishing boat trailing a drift net, but its "net" is more nearly like a group of high-voltage wires, so deadly is the sting of the tentacles to almost any fish or other small animal unlucky enough to encounter them.

           The true nature of the man-of-war is difficult to grasp, and indeed many aspects of its biology are unknown. But, as with Velella, the central fact is that what appears to be one animal is really a colony of many different indiviudals, although no one of them could exist independently. The float and its base are thought to be one individual; each one of the long trailing tentacles another. The food-capturing tentacles, which in a large specimen may extend down for 40 or 50 feet, are thickly studded with nematocysts or stinging cells, Because of the toxins injected by these cells, Physalia is the most dangerous of all the coelenterates.

           For the human bather, even glancing contact with one of the tentacles produces a fiery welt; anyone heavily stung is fortunate to survive. The exact nature of the poison is unknown. Some people believe there are three toxins involved, one pro­ducing paralysis of the nervous system, another affecting respiration, the third resulting in extreme prostration and death, if a large dose is received: In areas where Physalia is abundant, bathers have learned to respect it. On some parts of the Florida coast the Gulf Stream passes so close inshore that many of these coelenterates are borne in toward the beaches by onshore winds. The Coast Guard at Lauderdale-by-the-Sea and other such places, when posting reports of tides and water temperatures, often includes fore­casts of the relative number of Physalias to be expected inshore.

           Because of the highly toxic nature of the nematocyst poisons, it is extraordinary to find a creature that apparently is unharmed by them. This is the small fish Nomeus, which lives always in the shallow of a Physalia. It has never been found in any other situation. It darts in and out among the tentacles with seeming impunity, presumably finding among them a refuge from ene­mies. In return, it probably lures other fish within range of the man-of-war. But what of its own safety? Is it actually immune to the poisons? Or does it live an incredibly hazardous life? A Japanese investigator reported years ago that Nomeus actually nibbles away bits of the stinging tentacles, perhaps in this way subjecting itself to minute doses of the poison throughout its life and so acquiring immunity. But some recent workers contend that the fish has no immunity whatever, and that every live Nomeus is simply a very lucky fish.

           The sail, 'or float, of a Portuguese man-of-war is filled with gas secreted by the so-called gas gland. The gas is largely nitro­gen (85 to 91 per cent) with a small amount of oxygen and a trace of argon. Although some siphonophores can deflate the air sac and sink into deep water if the surface is rough, Physalia apparently cannot. However, it does have some control over the position and degree of expansion of the sac. I once had a graphic  demonstration of this when I found a medium-size man- of-war stranded on a South Carolina beach. After keeping it overnight in a bucket of salt water, I attempted to return it to the sea. The tide was ebbing; I waded out into the chilly March water, keeping the Physalia in its bucket out of respect for its stinging abilities, then hurled it as far into the sea as I could. Over and over, the incoming waves caught it and returned it to the shallows. Sometimes with my help, sometimes without, it would manage to take off again, visibly adjusting the shape and position of the sail as it scudded along before the wind, which was blowing out of the south, straight up the beach. Sometimes it could successfully ride over an incoming wave; sometimes it would be caught and hustled and bumped along through thinning waters. But whether in difficulty or enjoy­ing momentary success, there was nothing passive in the attitude of the creature. There was, instead, a strong illusion of sentience. This was no helpless bit of flotsam, but a living creature exerting every means at its disposal to control its fate. When I last saw it, a small blue sail far up the beach, it was pointed out to sea, wait­ing for the moment it could take off again.

Silent Spring

The late 1950s and early 1960s saw the introduction of numerous chemicals which began to change almost every facet of modern life, from the foods we ate, to building products and how we related to nature. The new chemicals were generally considered to be major, important advancements. Then came Silent Spring. The following excerpt from Always, Rachel: The Letters of Rachel Carson and Dorothy Freeman (edited by Martha Freeman) describes the response to Silent Spring by the chemical industry.

            The first installment of Silent Spring appeared in the New Yorker for June 15, 1962. It caused an immediate sensation throughout the country and became the target of a savage and relentless attack by the pesticides industry. Rachel bad been warned of the storm her book would create, but she could hardly have foreseen its extent and its ferocity, which included personal attacks on this "hys­terical woman." Pesticide manufacturers were unable to refute her allegations (she had source references for every statement she had made) so they treated the whole matter as a publicity problem. The National Agricultural Chemicals Association appropriated a quarter of a million dollars "to improve the image of the industry" (an action that backfired by giving Silent Spring publicity on a scale that no book publisher could afford).

            The fury with which the book and its author were attacked had, I believe, deeper roots than the chemical companies' concern for profits. After all, DDT and other pesticides were not a vital part of their business. Her attackers must have realized that she was questioning not simply the use of poisons, but the ba­sic irresponsibility of our industrial society toward the natural world: the belief that damage to nature was an inevitable cost of "progress." That was her heresy.

             Water, soil, and the earth's green mantle of plants make up the world that supports the animal life of the earth. Although modern man seldom remembers the fact, he could not exist without the plants that harness the sun's energy and manufacture the basic foodstuffs he depends upon for life. Our attitude toward plants is a singularly narrow one. If we see any immediate utility in a plant we foster it. If for any reason we find its presence undesirable or merely a matter of indifference, we may condemn it to destruction forthwith. Besides the various plants that are poisonous to man or his livestock, or crowd out food plants, many are marked for destruction merely because, according to our narrow view, they happen to be in the wrong place at the wrong time. Many others are destroyed merely because they happen to be associates of the unwanted plants....

            One of the most tragic examples of our unthinking bludgeon­ing of the landscape is to be seen in the sagebrush lands of the West, where a vast campaign is on to destroy the sage and to substitute grasslands. If ever an enterprise needed to be illumi­nated with a sense of the history and meaning of the landscape, it is this. For here the natural landscape is eloquent of the interplay of forces that have created it. It is spread before us like the pages of an open book in which we can read why the land is what it is, and why we should preserve its integrity. But the pages lie unread.

            The land of the sage is the land of the high western plains and the lower slopes of the mountains that rise above them, a land born of the great uplift of the Rocky Mountain system many millions of years ago. It is a place of harsh extremes of climate: of long winters when blizzards drive down from the mountains and snow lies deep on the plains, of summers whose heat is relieved by only scanty rains, with drought biting deep into the soil, and drying winds stealing moisture from leaf and stem....

            Justice William O Douglas, in his recent book My Wilderness: East to Katahdin, has told of an appalling example of ecological destruction wrought by the United States Forest Service in the Bridger National Forest in Wyoming. Some 10,000 acres of sagelands were sprayed by the Service, yielding to pressure of cattlemen for more grasslands. The sage was killed, as intended. But so was the green, life giving ribbon of willows that traced its way across these plains, following the meandering streams. Moose had lived in these willow thickets, for willow is to the moose what sage is to the antelope. Beaver had lived there, too, feeding on the willows, felling them and making a strong dam across the tiny stream. Through the labor of the beavers, a lake backed up. Trout in the mountain streams seldom were more than six inches long; in the lake they thrived so prodigiously that many grew to five pounds. Waterfowl were attracted to the lake, also. Merely because of the presence of the willows and the beavers that depended on them, the region was an attractive recreational area with excellent fishing and hunting.

            But with the "improvement" instituted by the Forest Service, the willows went the way of the sagebrush, killed by the same impartial spray. When Justice Douglas visited the area in 1959, the year of the spraying, he was shocked to see the shriveled and dying willows the "vast, incredible damage." What would become of the moose? Of the beavers and the little world they had constructed? A year later he returned to read the answers in the devastated landscape. The moose were gone and so were the beaver. Their principal dam had gone out for want of at­tention by its skilled architects, and the lake had drained away. None of the large trout were left. None could live in the tiny creek that remained, threading its way through a bare, hot land where no shade remained. The living world was shattered....

             The Japanese beetle, an insect accidentally imported into the United States, was discovered in New Jersey in 1916, when a few shiny beetles of a metallic green color were seen in a nursery near Riverton. The beetles, at first unrecognized, were finally identified as a common inhabitant of the main islands of Japan.  Apparently they had entered the United States on nursery stock imported before restrictions were established in 1912....

            The Michigan spraying was one of the first large-scale attacks on the Japanese beetle from the air. The choice of aldrin, one of the deadliest of all chemicals, was not determined by any peculiar suitability for Japanese beetle control, but simply by the wish to save money -- aldrin was the cheapest of the com­pounds available. While the state in its official release to the press acknowledged that aldrin is a "poison," it implied that no harm could come to human beings in the heavily populated areas to which the chemical was applied. (The official answer to the query "What precautions should I take?" was "For you, none.") An official of the Federal Aviation Agency was later quoted in the local press to the effect that "this is a safe operation" and a representative of the Detroit Department of Parks and Recreation added his assurance that "the dust is harmless to humans and will not hurt plants or pets." One must assume that none of these officials had consulted the published and readily available reports of the United States Public Health Service, the Fish and Wildlife Service, and other evidence of the extremely poisonous nature of aldrin.

            Acting under the Michigan pest control law which allows the state to spray indiscriminately without notifying or gaining permission of individual landowners, the low-lying planes began to fly over the Detroit area. The city authorities and the Fed­eral Aviation Agency were immediately besieged by calls from worried citizens. After receiving nearly 800 calls in a single hour, the police begged radio and television stations and news­papers to "tell the watchers what they were seeing and advise them it was safe," according to the Detroit News. The Federal Aviation Agency's safety officer assured the public that "the planes are carefully supervised" and "are authorized to fly low." In a somewhat mistaken attempt to allay fears, he added that the planes had emergency valves that would allow them to dump their entire load instantaneously. This, fortunately, was not done, but as the planes went about their work the pellets of insecticide fell on beetles and humans alike, showers of "harm­less" poison descending on people shopping or going to work and on children out from school for the lunch hour. House­wives swept the granules from porches and sidewalks, where they are said to have "looked like snow." As pointed out later by the Michigan Audubon Society, "In the spaces between shingles on roofs, in eaves-troughs, in the cracks in bark and twigs, the little white pellets of aldrin-and-clay, no bigger than a pin head, were lodged by the millions ... When the snow and rain came, every puddle became a possible death potion."

            Within a few days after the dusting operation, the Detroit Audubon Society began receiving calls about the birds. Accord­ing to the Society's secretary, Mrs. Ann Boyes, "The first indication that the people were concerned about the spray was a call I received on Sunday morning from a woman who re­ported that coming home from church she saw an alarming number of dead and dying birds. The spraying there had been done on Thursday. She said there were no birds at all flying in the area, that she had found at least a dozen [dead] in her backyard and that the neighbors had found dead squirrels." All other calls received by Mrs. Boyes that day reported "a great many dead birds and no live ones... People who had maintained bird feeders said there were no birds at all at their feeders." Birds picked up in a dying condition showed the typical symptoms of insecticide poisoning -- tremoring, loss of ability to fly, paralysis, convulsions.

            Nor were birds the only forms of life immediately affected. A local veterinarian reported that his office was full of clients with dogs and cats that had suddenly sickened. Cats, who so meticulously groom their coats and lick their paws, seemed to be most affected. Their illness took the form of severe diarrhea, vomiting, and convulsions. The only advice the veterinarian could give his clients was not to let the animals out unneces­sarily, or to wash the paws promptly if they did so. (But the chlorinated hydrocarbons cannot be washed even from fruits or vegetables, so little protection could be expected from this measure.)

            Despite the insistence of the City-County Health Commis­sioner that the birds must have been killed by "some other kind of spraying" and that the outbreak of throat and chest irrita­tions that followed the exposure to aldrin must have been due to something else," the local Health Department received a con­stant stream of complaints. A prominent Detroit internist was called upon to treat four of his patients within an hour after they had been exposed while watching the planes at work. All had similar symptoms: nausea, vomiting, chills, fever, extreme fatigue, and coughing.

            The Detroit experience has been repeated in many other com­munities as pressure has mounted to combat the Japanese beetle with chemicals. At Blue Island, Illinois, hundreds of dead and dying birds were picked up. Data collected by birdbanders here suggest that 80 per cent of the songbirds were sacrificed. In Joliet, Illinois, some 3000 acres were treated with heptachlor in 1959. According to reports from a local sportsmen's club, the bird population within the treated area was "virtually wiped out." Dead rabbits, muskrats, opossums, and fish were also found in numbers, and one of the local schools made the collec­tion of insecticide-poisoned birds a science project....

            Incidents like the eastern Illinois spraying raise a question that is not only scientific but moral. The question is whether any civilization can wage relentless war on life without destroying itself, and without losing the right to be called civilized. . .

             For each of us, as for the robin in Michigan or the salmon in the Miramichi, this is a problem of ecology, of interrelationships, of interdependence. We poison the caddis flies in a stream and the salmon runs dwindle and die. We poison the gnats in a lake and the poison travels from link  to link of the food chain and soon the birds of the lake margins become its victims. We spray our elms and the following springs are silent of robin song, not because we sprayed the robins directly but because the poi­son traveled, step by step, through the now familiar elm leaf-earthworm-robin cycle. These are matters of record, observ­able, part of the visible world around us. They reflect the web of life  or death that scientists know as ecology.

             Within the period covered by the rise of modern pesticides, the incidence of leukemia has been steadily rising. Figures available from the National Office of Vital Statistics clearly estab­lish a disturbing rise in malignant diseases of the blood-forming tissues. In the year 1960, leukemia alone claimed 12,290 victims. Deaths from all types of malignancies of blood and lymph totaled 25,400, jncreasing sharply from the 16,690 figure of 1950. In terms of deaths per 100,000 of population, the increase is from 11.1 in 1950 to 14.1 in 1960. The increase is by no means confined to the United States; in all countries the recorded deaths from leukemia at all ages are rising at a rate of 4 to 5 per cent a year. What does it mean? To what lethal agent or agents, new to our environment, are people now exposed with increasing frequency?

            Such world famous institutions as the Mayo Clinic admit hundreds of victims of these diseases of the blood-forming organs. Dr. Malcolm Hargraves and his associates in the Hematology Department at the Mayo Clinic report that almost without ex­ception these patients have had a history of exposure to various toxic chemicals, including sprays which contain DDT, chlor­dane, benzene, lindane, and petroleum distillates.

 The Sense Of Wonder

            If a child asked me a question that suggested even a faint awareness of the mystery behind the ar­rival of a migrant sandpiper on the beach of an August morning, I would be far more pleased than by the mere fact that he knew it was a sandpiper and not a plover....Those who dwell, as scientists or laymen, among the beauties and mysteries of the earth are never alone or weary of life. Whatever the vexations or concerns of their personal lives, their thoughts can find paths that lead to inner contentment and to renewed excitement in living. Those who con­template the beauty of the earth find reserves of strength that will endure as long as life lasts. There is symbolic as well as actual beauty in the migration of the birds, the ebb and flow of the tides, the folded bud ready for spring. There is something infinitely healing in the repeated refrains of nature-the assurance that dawn comes after night, and spring after the winter.