Proving Ground (Chapter Two)

Explore Collection

The following text is excerpted by permission from the University of Washington Press from the book Proving ground; an account of the radiobiological studies in the Pacific, 1946-1961, by Neal O. Hines, Seattle, Wash.: University of Washington Press, 1962.

(Original Bibliographic Endnotes not included)


Operation Crossroads unquestionably was the most thoroughly documented, reported, and publicized peacetime military exercise in history. The official records filled volumes. Coverage by the press was authorized by the White House on recommendation of the Joint Chiefs of Staff, and the task force was accompanied by a press headquarters ship, the transport Appalachian. Also with the approval of the President, observers from eleven nations having memberships in the United Nations Atomic Energy Commission were invited to go to Bikini aboard the transport Panamint. Such concentration of attention, quite apart from the sheer size of the operation, gave Crossroads the quality of the spectacular. The tests were necessary, it was explained, to examine the effects of nuclear blasts on naval vessels. The tests were necessary to the further evaluation of the atomic bomb as a strategic weapon. These reasons would do. The tests were, indeed, full of portent, as the literature of the period so copiously pointed out. Yet the unique contribution of Crossroads was its mobilization of scientific interests. It managed to bring to bear on an obscure atoll not only the interests so suddenly enlarged by the physical sciences but by those of virtually the whole range of scientific disciplines. Crossroads provided a reason and a theater for studies that would have been impossible at any earlier time. Thousands of scientists took part, many of them still in uniform and fulfilling a final military obligation before returning to their universities and laboratories. The impact of this shared and concentrated effort was somehow greater, in the end, than the impact of the atomic detonations themselves, shattering as they proved to be.

Admiral Blandy originally had established a target date of May 15 for the beginning of the tests and preliminary work in the Bikini area had been authorized in January, 1946. The destroyer Sumner (DD 692) first was dispatched to Bikini to conduct hydrographic surveying, and she was followed by vessels carrying scientific teams carrying out preliminary oceanographic, biological and geological surveys for which the headquarters ship was the U.S.S. Bowditch (AGS 4).1 The field work thus begun in March was continued through the summer until the operation was concluded in August. Meantime, however, on March 22, as a construction battalion arrived at Bikini to prepare the extensive shore facilities, a delay of the tests was ordered by President Truman to permit Congressional observers to attend. A new target date of July 1 was established. Whatever its other effects, the delay provided additional time for measurements and observations of a variety and intensity never before focused on an atoll.

Bikini lies in the path of the North Equatorial Current, a product of a wind system of the Pacific, which moves west across the ocean from the coast of North America to a region east of the Philippines, where it divides and doubles back as the Japan Current, circling the north rim of the Pacific basin, and the Equatorial Countercurrent, flowing eastward just north of the Equator. The trade winds maintain their most constant velocity, about 18 knots, during the winter months, but at other seasons their streams of wind of the northern and southern hemispheres shift to the north—the zone of the southeast trades extending in some areas to 10° N. latitude, almost as far north as Bikini—and in these periods the Northern Marshalls lie in an area of lighter, variable winds. Storms are not frequent, but they occur occasionally in summer and autumn, striking from the southeast, the direction of a seasonal ocean swell generated by winter storms in the southern hemisphere. The average monthly mean temperature varies throughout the year only from 80 to 83 degrees.

Bikini is an atoll of irregular outline, roughly oval in shape and exhibiting many of the classic characteristics of atoll growth—the strong reefs built to windward, the protected leeward entrances, the lagoon having a maximum depth of about thirty-two fathoms, and the principal islands linked by the long stretches of sandy reef which trace the edges of the coral cup. Bikini Island, largest of the twenty-six islands and islets, is two and one-half miles long and one-half mile wide, with about 540 acres of dry land. It rests on a reef whose outer edges, cut by surge channels, stretch outward toward and into the ocean in the direction of the prevailing winds. Southward from Bikini Island the long line of reef sand contains only patches of islet vegetation until the reef widens out at Enyu Island, the second largest island of the atoll, which flanks the wide southeast entrance called Enyu Passage. Westward from Bikini Island is the long northern reef of the atoll, a meander line of coral sand unmarked for almost twenty miles except, at its mid-point, by a northward pointing reef projection supporting an island cluster which includes Aomoen (Amen) Island.2

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Bikini's lagoon is about twenty-six miles long from east to west and fifteen miles wide from north to south. The lagoon covers two hundred and forty-three square miles and the land, omitting inter-tidal areas, totals 3.4 square miles. Most of the islands are only eight to twelve feet above the low tide level (mean spring high tides rise 5.5 feet), but points on Bikini Island were sixteen to nineteen feet high, and on Romurikku Island, west of Aomoen, a dune had risen twenty-three feet above the reef flat.

Bikini's coral rim is penetrated by a number of passes, the largest of them Enyu Passage, which is nine miles wide and which hides a characteristic atoll entrance sill only four to ten fathoms below the surface of the water. All of the other passes are on the protected southwest curve of the atoll, none wider than about a mile and the deepest of them thirty-fathom Enirik Pass, between Eniirikku and Eninman Islands.

In the preparations for Crossroads the imminent release of unprecedented amounts of radioactive materials was a consideration given attention at every turn. There was an appropriate attention to radiation measurement and radiation safety. Because the military problem obviously required assessment of the effects of blast and of thermal and nuclear radiations on living organisms, test animals were to be stationed on twenty-two vessels of the target fleet under various conditions of nearness to and shielding from the explosions.3 The Radiation Safety Section took to Bikini more than 25,000 counters, film badges, and other devices. The studies of the Oceanographic Group were directed at determining lagoon currents so that post detonation upwellings of contaminated water could be anticipated and plotted. In all of these preparations there was realization of the need to extract from the tests all possible information concerning the radiation factor. There is no evidence, however, that Crossroads was then considered the possible starting point of long-term research in radiobiology or that Bikini might offer means of discovering how radionuclides were caught up and circulated in a biological system. Although the concept of such circulation was not altogether new, its relevance in the Bikini situation seems not to have been realized.

Admiral Blandy's letter of appointment directed him to include civilian scientists in the task force organization, to arrange tests to note "the effects of atomic explosives against ground and air targets and to acquire scientific data of general value if this is practicable," and to collaborate with the test evaluation board to be appointed separately by the Joint Chiefs.4 The Joint Chiefs also indicated an interest in air detonation and in underwater detonation "if the latter is considered feasible." Blandy was assisted by a staff including two deputy task force commanders. Rear Admiral W. S. Parsons, the Deputy for Technical Direction, having in turn a staff of four special assistants, including John von Neumann, Scientific Adviser, two technical administrators, and two technical advisers. One of the technical advisers was Stafford Warren, who was both Radiological Safety Adviser and head of the Radioactivity Group. With Warren, assigned as radiation monitors, were representatives of the Applied Fisheries Laboratory: Donaldson, Welander, and Clarence F. Pautzke, a biologist with the Washington State Game Department, who had assisted in the selection of salmon for the Laboratory's X-radiation studies. They went to the Pacific aboard the U.S.S. Haven, a hospital ship employed in the operation because of the facilities it provided for laboratory work, and they were in the Bikini area from June 12 to August 16.

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The first Bikini explosion, Test Able, the air drop of an atomic bomb of nominal yield, took place at approximately 9 A.M., July 1, 1946 (Bikini time). The bomb was dropped from a B-29 aircraft, Dave's Dream, and the aiming point was the battleship Nevadastationed in the center of the target fleet. Near the Nevada were two Japanese warships, the battleship Nagato and the light cruiser Sakawa, and other major vessels including the destroyer Hughes, the aircraft carrier Independence, the cruiser Pensacola, and the submarine Skate. The bomb burst as planned some 500 feet over the target array, but the burst was approximately 1,500 feet to the west of the Nevada, the intended zero point. The result was surprising, perhaps, only to those who had expected something near total elimination of the target fleet. The destruction, although far short of total, was awesome enough. Five ships were sinking. The attack transports Gilliam and Carlisle, vessels of approximately 450 feet in length, sank immediately—the Gilliam, closest of all target ships to the actual point of detonation, within one minute, and the Carlisle about forty minutes later. The destroyers Anderson and Lamson, vessels of 338 and 344 feet, were mortally stricken, the Anderson going down almost at once. The Sakawa was in flames astern and would sink on the morning of July 2 after she had burned for twenty-four hours and despite efforts to tow her to a beach. Other vessels were badly mauled and burning or made unapproachable by irradiation. The hull of the Independence was buckled and wrinkled, the remnants of her superstructure hopelessly tangled, and her 600-foot flight deck broken in several places. The Arkansas, oldest vessel in the United States fleet, was heavily damaged and burning, although she lived through the test. The carrier Saratoga, the cruisers Salt Lake City and Pensacola, and destroyers such as the Hughes were hit hard. Other ships, including the Nevada, the target vessel, escaped with only moderate damage. Surviving ships showing signs of irradiation were washed down in the course of fire-fighting and salvage operations, which began as soon as radiological patrols had scouted the target area. By 2:30 P.M. on July 2 Admiral Blandy had declared the lagoon safe for re-entry by all ships, and by the evening of Able Day eighteen of the target ships had been reboarded by special teams assigned to recover scientific instruments and to bring off test animals that had been placed throughout the target fleet.

The second device was exploded in Test Baker at 8:35 A.M., July 25 (Bikini time). The intervening days had been devoted to assessment of damage sustained by target vessels, to salvaging and re-equipping ships not too badly damaged for use with the under-water test, and to making preliminary examinations of test animals. Test Able had been observed by 114 representatives of press, radio, news picture services, and magazines. Before Test Baker, thirty-nine of these, and eight members of the Congressional delegation, returned to the United States. The preparations for Test Baker included rearrangement of the target ships about the small landing craft, the LSM 60, beneath which, at a depth of ninety feet—approximately half the distance to the lagoon bottom—the atomic device would be suspended. Elaborate arrangements were made for measuring water pressure and wave height. A final rehearsal was held on July 19. Although a weather front threatened on July 24 to disrupt the projected detonation schedule, the chance seemed good that the front would move away and Admiral Blandy decided early on the morning of that day to order the test program to proceed. Most of the support ships evacuated the lagoon on the evening before Baker Day, standing off Bikini at a distance of a dozen or so miles. The last vessels moved out through Enyu Passage shortly after 6 A.M. on July 25. In the center of the target array was the LSM 60 bearing a tall antenna designed to receive the line-of-sight electronic signal that would detonate the device beneath her hull.

Test Baker was the first occasion in which an atomic device was exploded in such a way that fission products were mixed with water and thus returned in great measure to the area of detonation. The air burst of July 1, despite the damage it had inflicted, scarcely had prepared observers for the wrath of sound, light, and volcanic shock that erupted within the lagoon. At the moment of explosion a giant bubble, brilliantly lighted within by incandescent materials, burst from the surface of the water to be followed by an "opaque cloud" which quickly covered about half of the ships of the target fleet. Within seconds the cloud had vanished and a hollow column 2,200 feet in diameter and containing some 10 million tons of water rose from the surface of the lagoon to a height of more than a mile. The 26,000-ton battleship Arkansas, broad-side to the LSM 60 but more than 500 feet away, was lifted and up-ended in the column before she was plunged to the bottom. At the base of the column was a tumult of foam several hundred feet high, and the descent of the water back into the lagoon set up a base surge from which rolled waves eighty to one-hundred feet high. The waves subsided rapidly as they proceeded outward, and the highest wave recorded at Bikini Island, three miles away, was seven feet, not sufficiently high to pass over the island or to cause damage there. The victims of the explosion, beyond the Arkansas, included the carrier Saratoga, which sank after seven and one-half hours; a landing ship, a landing craft, and an oiler; submerged submarines, including the Apogon; and the already-damaged battleship Nagato, which went down five days later.  The destroyer Hughes and the transport Fallon, seriously crippled and listing, were beached.

Radioactivity in the waters of the lagoon was intense. The volume immediately after the burst was estimated in the round, by the Evaluation Board, to be the equivalent of "many hundred tons of radium." The target ships were drenched by radioactive substances as the tremendous pillar of water crashed back into the lagoon. As the weight of the column subsided, the target area became a maelstrom of radioactive debris, and at the bottom of the lagoon was a shallow basin half a mile wide from which the force of the explosion had scooped hundreds of thousands of tons of sludge and coral-algal sediment. The upper levels of the lagoon waters remained highly radioactive for days and large areas were impenetrable by the small craft engaged in attempting to outline the swirling areas of contamination. After four days it still was not safe for inspection parties to spend any useful time at the target area or to board surviving ships floating there. Within the waters, and particularly in the tons of sludge again settling to the lagoon floor, were radioactive contaminants whose disposition would present problems of greater complexity than anyone at that point in time might have guessed.

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Before the Baker test, all discussions of probable effect were theoretical. Questions relating to underwater shots apparently had been debated at length while the Operation Crossroads plan was in the process of development. The debate, however, had turned principally on questions of physical effect and on the creation of a test that would yield new information on force and pressure. One view seems to have been that a detonation only slightly beneath the surface of the water would be particularly ineffective because, as was stated in a subsequent report, "neither the air pressure wave nor the water pressure wave would be maximized, and it is possible that a curtain of spray might be thrown up which would actually screen off a large part of the pressure wave in air and nearly all the thermal radiation, gamma radiation, and neutron radiation." In an approximate sense, this is what actually happened at Test Baker, in which the atomic device was exploded at a medium depth in the lagoon, but in the Baker case a major percentage of the long-lived fission materials also was mixed with water and suspended minerals and was captured and retained by the lagoon. The pre-Crossroads expectation may have been substantially correct, for the water erupting into the stupendous column did screen and dampen the effect of radioactivity at the instant of the detonation, but the possible long-term result either was utterly unforeseen or placed in such conjectural terms that its relevance, even to strategic considerations, was not understood.

For a week after Test Baker the radiological teams patrolled Bikini lagoon. The work of the biologists, however, soon turned from monitoring to sampling and analysis. Among the teams on the Haven were representatives of other laboratories who were beginning to share a curiosity about the disposition of radioactivity in a biotic system. Warren, still interested in the problems that had produced the program at Hanford, was eager to see the problems pursued at Bikini. Accordingly, there was formed informally within the Radiological Safety Section a "Division of Radiobiology."

The Division was setting itself to investigate the presence of radioactivity in an aquatic biological web of extreme complexity.5 At the base of the ocean food chains are the plankton—phytoplankton and zooplankton, vegetable and animal—and the algae. Most of the marine plants are in the phylum Thallophyta, composed of primitive plants having no true root, stem, or leaf, and which includes the algae and fungi. The simplest forms of the invertebrates begin with the Protozoa, single-celled organisms which include the Dinoflagellata, a borderline group having characteristics of both animals and plants, and the Foraminifera, which are planktonic in life and whose rudimentary skeletal structures ultimately sink to the bottom of the ocean where their fossil remains are found in geological strata. There are more than 1,200 species of Foraminifera, and 18,000 living and extinct species have been catalogued. In the waters are thousands of groups and species of invertebrate organisms, multicellular animals such as the sponges, of which there are some 2,500 species; the Arthropoda, including the copepods, which comprise about 70 per cent of the zooplankton; the gastropods, which are shelled creatures, using a foot for creeping; and the cephalopods, which include the octopi. The vertebrates include the primitive fishes, the sharks, and the rays; the true fishes, predominantly carnivorous; the reptiles, including the sea turtles; and the Cetacea, among whose members are the whales and dolphins.

In the mid-Pacific, as in the vicinity of Bikini, the identifiable species of fish total more than 600 and in the open ocean the number has been estimated at more than 1,000. Most species are carnivorous, but some, like the goatfish, the mullet, and the surgeonfish, are herbivorous, feeding on marine vegetation and plankton, and a few, the parrot fish, the triggerfish, and the puffer, are omnivores. The food chains may be short and relatively simple. The surgeonfish, for example, is an herbivore feeding on algae, but he in turn is preyed upon by sharks and grouper, the larger, far-ranging carnivores. The simple protozoa are fed upon by gastropods, which become the prey of small carnivores such as the cardinal fish. The carnivorous goatfish feeds only on organisms found in the shallower areas of the ocean, and this also is the habit of the wrasse. But the food chains may not only be infinitely more complicated but further confused by the seasonal character of the feeding habits of some of the species. Along each of the strands of this ecological web are species of plants and animals important to man, species of plants that live in the ocean-conditioned soils of the islands and of molluscs, crustacea, and fish—sharks, tuna, barracuda, herring, tarpons, jacks, mackerel, pike, and snappers—that are elements in the diet of people who live on the Pacific or on the lands about its rim.

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In such an environment, Bikini's lagoonal contamination, after the first days, was comprehensible only in relation to the biological uptake of fission products. In waters containing such a variety of biological forms, only ingested radioactivity—activity within the organs and tissues of living creatures or assimilated by aquatic plants—could provide clues to the condition of the atoll. Fish or other creatures killed by blast, heat, or massive doses of external radioactivity were not to be found in large numbers because they had been lost in the waters or consumed by the rapacious life of the lagoon. It was with the question of biological uptake that the Division of Radiobiology became concerned. The investigations were crude and, by later standards, wholly inadequate. It was not without significance, however, that the group achieved so early a measure of identity. Nowhere in the tables of organization of Joint Task Force One was there a specific radiobiological section. The Division of Radiobiology of the Radiological Safety Section was, in fact, a commissioned-in-the-field group composed of members of the Applied Fisheries staff and others who, under Warren's direction, organized themselves to pursue biological evidence of Test Baker radiation phenomena.

Early in August, Welander reported:

On and after Baker Day, 25 July 1946, the Radiobiological Survey party under the leadership of Dr. L. R. Donaldson has taken biological specimens consisting of fish, clams, sea cucumbers, coral, and algae from various parts of the lagoon and the surrounding area for the purpose of determining the amounts of radioactive substances in these animals and plants. Tissues or parts of the above specimens were analyzed in the Tablet Counting Laboratory on board the U.S.S. Haven under the direction of Dr. W. Langham and Mr. J. Martens.

In no case were any of the biological specimens taken within the lagoon entirely free of radioactive contamination. In general, the algae proved to have the highest activity and in consequence fish and other animals feeding on the algae also show high activity. Such analyses included beta and gamma measurements which presuppose the presence of alphas. However, the current low beta and gamma counts do not indicate any reduction in alpha activity.

Because of the highly poisonous nature of the fission products, and the increasing difficulty of detecting alpha emitters in the tissues of these marine animals, it is recommended that no fish, mollusk, or other marine animal taken within 100 miles of Bikini lagoon be used as food.

Plotting boards were used on the MountMcKinley, the task force flagship, to maintain records of the outlines of radioactivity developing within the lagoon. The biological dispositions of radioactivity could not be so outlined, but they had a bearing, nevertheless, on considerations of interest to the Navy. Support vessels returning to the lagoon after the underwater test had reported almost immediately the presence of radioactive contamination in water systems, in marine growths attached to the ships' hulls, and even in shipboard areas presumably inaccessible to contamination. The levels of radioactivity in the lagoon were found to be rising at night and falling in daylight hours, a circumstance later realized as attributable to the vertical movement of lagoonal plankton in response to light. Hulls of the vessels showed so much evidence of contamination that orders were issued two days after Baker for all personnel to move back from them, to sleep and work away from possibly contaminated bulkheads. Scrubdowns and changes of clothing had been ordered in the posttest period for persons returning from off-ship duty, yet contamination was found on handrails, in the galleys, and in the shipboard laboratories where scientists worked with instruments and samples. The necessity for frequent changes of clothes and boots exhausted Navy supplies. The monitor boats became contaminated as they worked long hours at surveys conducted among the units of a Bikini fleet that included the empty, battered, untouchable survivors of atomic explosion. The task force attitude was one of alert interest in every facet of the problem on which the scientific staffs could possibly shed any light, yet the biological base of many of the contamination problems was not yet fully realized.

Between June 14, when the Applied Fisheries group arrived at the atoll, and June 29, two days before Test Able, members had collected a total of 1,926 fish to be used as controls and in subsequent studies of the normal Bikini fish population. From July 2 to July 24, between the Able and Baker tests, an additional catch of 1,819 fish was made, this both to note the effects of the Able explosion and to extend the general knowledge of lagoon fauna. After Baker day, from July 25 to August 13, the group collected an additional 1,407 fish, and these provided materials for further counting of activity and for future analysis of radiation effects. By the end of the Crossroads period, the staff had made counts of activity in 1,021 samples of tissue from 119 fish, the date and place of the capture, the date of radioanalysis, and the record of radioactive content being noted in each instance. A large proportion of the work remained to be done and more exact radioanalysis attempted in laboratory conditions.6

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The collections of fish and other specimens were made by members of the Laboratory staff working as teams in the waters and on the reefs. The method was slow, yet none of the collections made in succeeding years resulted in fundamental improvement because of the need to take samples by type and place and with a considerable attention to selectivity. The early Crossroads plan had anticipated the use of commercial fishing gear for sweeping up fish in the lagoon and in the waters outside the atoll, but this arrangement was abandoned. Collections of fish were made in the lagoon by poisoning tide pools with derris root, which stunned the fish and permitted them to be picked up at the surface or by diving. The larger fish were caught, inside or outside the lagoon, by hook and line, although this system was, in fact, acknowledged to be "too selective for good sampling." Algae, coral, and reef forms were taken from the reefs at low tide or by diving near the lagoonal coral heads or, occasionally, with a dredge. Visits to collection points were made in one of the U.S.S. Haven's whaleboats, the landings on the beaches being accomplished by rubber rafts. Landing craft were used when they were available, but the rubber raft demonstrated its superiority in beach landings made over rough coral or in turbulent waters.

The team method of collection forced selectivity of sample and location. In a lagoon twenty-six miles long and presenting a water area of almost 250 square miles, the sampling of aquatic life could be accomplished only at those points that were presumed to hold materials of interest. The points had to be chosen with as much knowledge as possible of the organic composition of the atoll and with some sensitivity, however rudimentary, to the ways the presence of radiation in the biological system might be revealed. The process of picking the collection points thus was directly related to radiobiological understanding which, in Bikini's aquatic environment, came to embrace the idea of radiation cycling in the biological system. If a collection point proved to hold contamination in unexpected amounts, it was apparent that the original expectation was wrong. The adjustment of the expectation involved searches for clues and reasons and new hypotheses.

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The movement away from Bikini began early in August, and by mid-September most of the support vessels would have departed. The pressure to conclude the operation was checked, however, by the need to determine the disposition of the target vessels, many of which still were dangerously radioactive, and to complete the observations that had to be made in the field.

Within Bikini lagoon, the intensity of residual radioactivity had been reduced to low levels by dilution and decay, but the diminution permitted a clearer view of the extent to which the residues had been taken up by the environment of the atoll and were behaving in response to biological influences. From August 2 to August 9, members of the Radiobiology Division made collections of fish and other samples at all previously determined stations and at several other points within the lagoon. In fish, the highest concentrations of radioactivity were in digestive tracts, and the highest activity counts were in those fish which feed on algae. In general the activity per unit of weight was greater in algae than in fish taken from the same station. Clams (Tridachnas) collected at the northeastern rim of the atoll, near Bikini Island, contained an abundance of radioactivity in digestive glands, but clams taken at Airukiiji (Arji) Island, flanking Enyu Passage to the west, contained only trace amounts. Coral samples containing living polyps held greater amounts of activity than samples from the same location where the corals had died. A number of organisms were beginning to die on the north reef between Bikini and Aomoen Islands, although the cause was unknown. By August 12 members of the biological team visiting the reef were picking up dead or weakened fish and dead sea urchins and clams. Notably, too, the fouling organisms on the ships' hulls were continuing to build up amounts of activity which seemed to be the result both of the direct absorption of materials and of the accumulations caused by the nightly surface migration of planktonic forms.

The radiobiological phenomena being revealed, whatever their relevance to military considerations, were of importance because of their bearing on the question of how soon the Bikini people could be returned to their atoll. The question was cited by Donaldson and his associates in their preliminary Radiobiology Division report to Warren and Joint Task Force One. In this the biologists said:

  1. The material gathered to date needs additional study along the following lines
    1. A number of activity counts on the material available, using better techniques, would provide quantitative and qualitative results.
    2. Studies of the tissues of controls and fish exposed to activity should be completed.
    3. The materials in the collections should be identified and the proper nomenclature used in reports.
  2. Additional collections should be made at Bikini.
    1. Collections in a period of about six months are needed especially from the northeast portion of the atoll.
    2. The collections would provide information on population changes, activity retention, and a distribution of active materials.
    3. Collections the year after the blast might be made to further the studies of population changes and provide information on genetic problems.

The Division also said that additional laboratory work was needed, particularly on the radiation absorption-retention relationships among aquatic organism and of the role of fouling organisms in the accumulation and retention of radioactivity in the aquatic environment. The recommendations seem peculiarly prescient. It is probable, however, that they reflected only a normal curiosity about an entirely new scientific problem that obviously needed very much more work but which was not apt to be examined further in the Crossroads context. In August, 1946, there was no reason for members of the Applied Fisheries Laboratory staff to believe that the problems of Bikini would be enlarged at Eniwetok and would continue to occupy their attention for many years. They were, in fact, expecting to return to the University to take up the X-radiation studies begun three years before.

In October, four Navy and Marine Corps lieutenants, members of the Radiological Safety Section, reported the results of a late-September survey of migratory fish—tuna, jacks, mackerel, and barracuda—caught in the waters off Ailinginae, Rongelap, Rongerik, and Wotho atolls.7 Sixty such fish were caught, their organs monitored with an X-263 G-M counter, and liver sections preserved in formalin for later and more accurate assessment of beta activity. None of the fish showed the presence of ingested radioactivity.

1 Institutions and agencies involved in the surveys were the Geological Survey, the Smithsonian Institution, the Fish and Wildlife Service, the Military Intelligence Division of the Office of the Chief of Engineers, the Woods Hole Oceanographic Institution, the Scripps Institution of Oceanography, the Division of War Research, and the University of Michigan. Among scientists conducting segments of the work were J. I. Tracey Jr. and H. S. Ladd, surface geology of coral reefs and islands;  K. O. Emery, submarine geology; C. C. Bates, beach studies; W. H. Munk, Gordon Riley, W. S. von Arx, and W. L. Ford, lagoon currents and diffusion and water exchange between lagoon and ocean; Leonard Schultz, lagoon and reef fishes; J. C. Marr and Vernon Brock, pelagic fishes; J. P. E. Morrison, mollusks, birds, and land animals; M. W. Johnson, plankton; W. R. Taylor, land and marine plants; and M. C. Sargent and T. S. Austin, organic productivity. (Roger Revelle, Foreword, "Bikini and Nearby Atolls: Part 1, Geology," Geology of Bikini and Nearby Atolls, Washington, D.C.: Government Printing Office, 1954, p. iv.)

2 To facilitate communications involving island sites the task force substituted simple code names for the Marshallese names of the islands. Bikini, Enyu, and Namu Islands retained their native names, but Aomoen became Amen, Ionchebi became Ion, and so on. Because a new set of code designations was assigned when Bikini became a part of the proving ground, the Marshallese names (most of them determined by a 1944 Decision List of the Board on Geographic Names) are used herein, the code names given, where appropriate, in parentheses.

3 Studies of test animals were under the direction of Captain R. H. Draeger, of the Naval Medical Research Section, whose executive officer was Captain Shields Warren, later the first Director of the Division of Biology and Medicine of the U.S. Atomic Energy Commission. Animals taken to Bikini included 200 pigs, 60 guinea pigs, 204 goats, 5,000 rats, and 200 mice.

4 The Evaluation Board, created by the Joint Chiefs of Staff on March 28, 1946, was headed by K. T. Compton, President of the Massachusetts Institute of Technology, and included six scientific and military representatives. The Board was to be available for advising the Commander of Joint Task Force One on test planning and to prepare for the Joint Chiefs an evaluation of test results. There was, in addition, a President's Evaluation Commission headed by Senator C. A. Hatch, of New Mexico, and on which President Compton also served. The Commission was to cooperate with the Secretaries of War and Navy during the test period and to submit to the President a final report of its conclusions and recommendations.

5 Names of pertinent scientific species are listed in Appendix II.

6 Field determinations of the presence of radioactivity were made with a Victoreen X-263 scaling counter, and all samples in which activity was detected were reserved for further analysis in X-327 counters. Values were made comparable by reducing all to counts in 0.01 gram of material.

7 The four were Lieutenants C. Carter, David Bradley, T. J. Madden, and F. C. Larson. Bradley later was the author of the Bikini diary, No Place to Hide.