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Mr. Merrill is a frequent contributor to THE SUBMARINE REVIEW and is a published author of several books on the history of undersea technology. He is a retired engineer with lengthy experience at the New London Lab of the Naval Undersea Warfare Center. He currently lives in Waterford, CT

“This new big science is called oceanography. It is the whole business of getting into the sea, finding out what is there, what is underneath, studying its chemistry, its physics.


Oceans with an average depth of 13,000 feet comprise about seventy-one percent of the total area of the earth and this provides an enormous challenge for ships on the surf ace and submarines below. Naval operational success at sea is dependent on knowledge concerning the sea’s natural and man-made ambient noise, current, tides, turbulence, depths, temperature, salinity, underwater ridges, winds, ice, and internal waves. Today, precise details and understanding of the sea is required for successful strategic and tactical operations with modem naval technology. At the start of the 20th century knowledge of the sea was at best fragmentary.

Although oceanography began when some first fact about the sea was observed and recorded, ” … it was not until about the middle of the nineteenth century that systematic examination even of the surface of the sea was seriously undertaken, or that scientists awoke to the fact that the underlying waters offered a whole new world of exploration.” Twentieth century technology advancements aided the broadening of marine research about the physical, chemical, and geological aspects of the seas. This new knowledge addressed Navy needs.

Throughout the entire 20th century that included two world wars, almost continuous improvements and advances in military technology; ships, aircraft, submarines, and weapons brought new challenges. The Navy required a more complete knowledge of the oceans to address at-sea operational requirements.

An effective relationship gradually developed between the Navy and the growing marine science community, each with divergent needs, one with science as the goal and the other with at-sea operational requirements. The Navy needed knowledge of the sea.

In April 1900, John Holland delivered HOLLAND VI, his modest but practical submarine, to the United States Navy. By the start of World War I (WWI), there were about 400 submarines worldwide. During the entire 20th century, along with the universal acceptance of the submarine there was an increasing demand for detailed knowledge of the nature of the submarine’s operational environment, the sea. Detecting and evading submarines became an imperative of the 20th century.

In 1973, an oceanographer assessing support for marine science in the United States for the period 1850-1940 concluded, “For marine science, a half-century of active if not sympathetic government support was over. In the next 40 years, those before the beginning of World War II (WWII), oceanography in the United States was largely supported by private institutions.”

WWII and the remainder of the 20th century witnessed a significant increase in Navy joint ventures with private sector marine science laboratories. An article in the November 1980 issue of Fortune noted that oceanography, an expensive science, was receiving a good portion of naval funds available for research on that science.

Roots for government support of gathering and disseminating ocean information became more highly focused in 1866, when an Act of Congress established the Hydrographic Office. The Act expanded hydrographic work and included “the carrying out of surveys, the collection of information and the printing of every kind of nautical chart or publication.” The Hydrographic Office provided oceanic support for the Navy by focusing on physical conditions, boundaries and currents; oceanography in addition includes study of marine life, physical chemistry of the ocean, and the geology of the ocean bottom. In 1962, the Hydrographic Office was designated the U.S. Naval Oceanographic Office.

The U.S. Coast and Geodetic Survey (C&GS) authorized in 1878 under the Treasury Department provided scientific support for marine research. In 1882, C&GS sponsored USS ALBATROSS, built exclusively for fisheries and marine research. At Woods Hole, Massachusetts, in 1885 the Survey constructed the first marine fishery research laboratory. These government agencies brought focus to marine research.

In January 1902, industrialist Andrew Carnegie, in the interest of science founded the Carnegie Institution of Washington. The endowment of $10 million dollars eclipsed the endowments at five Ivy League universities and was ten times greater than James Smithson’s bequest to the United States ultimately leading to the Smithsonian Institute. The Carnegie Institution authorized the construction of the wooden brigantine research ship CARNEGIE for making magnetic field measurements at sea. The vessel was commissioned in 1909 and widely used for research until I 929, when it was destroyed by fire. Throughout the 20th century and continuing into the new century, the Institution has steadily and broadly supported science research, including marine science.

Two small privately supported Marine Biological Laboratories were conducting marine research, one at Woods Hole, Massachusetts (1888) and one in La Jolla, California (1903). As late as the 1930s, ….. both were small, isolated institutions, each with staffs of about a dozen people, one ship, and limited research facilities.

The California laboratory became part of the University of California in 1912 and the name was changed to Scripps Institution of Oceanography (SIO) in 1925 to reflect a broadened research focus. The Navy Hydrographic office supported research projects at SIO as early as 1920. In 1931, 810 had one main laboratory building, one small research vessel, a staff of twenty-six, and an unsteady annual budget of $75,000.

In 1930, the Woods Hole laboratory filed articles of incorporation for the Woods Hole Oceanographic Institution (WHOI). Half of the support for Scripps came from the University of California while the Rockefeller Foundation was the principal patron for WHOI. Both institutes needed multiple sources of support.

Willard Bascom, noted scientist and oceanographer, observed “Until World War II, American oceanography consisted mainly of a few marine biologists based at the Scripps Institution of Oceanography in La Jolla, California and the Woods Hole Oceanographic Institution in Massachusetts.

Prior to substantial direct support for oceanography by the Navy during WWII, Hydrographer Admiral Walter R. Gherardi provided WHOI and SIO with seawater temperature, salinity, and dynamic-sounding data gathered by the Hydrographic Office crews. In the 1930s, SIO scientists conducted research on board Hydrographic vessels.

WWII operational requirements for surface ships, submarines, and naval aircraft (weather needs) created extensive and time-urgent needs by the Navy for oceanographic assistance. This wartime oceanographic support by the marine scientists heavily contributed to naval victory during the four-year war.

By mid-century, both WHOI and SOI became significant laboratories and known nationally and internationally. Before 1930 the number of United States oceanographers was about six. 9 Prior to WWII, the Hydrographic Office was the primary government agency interacting with private marine research. The onset of the war marked the beginning of a substantial involvement with the Navyand the marine laboratories which continued for the remainder of the century.

Marvin Lasky, in a review of scientific effort for ASW, 1939- 1945, points out “Prior to 1939 technical people in the field of underwater sound probably numbered fewer than 150; by 1945 more than 3,000 were involved.

Peace in 1945 did not end the Navy’s need for further information about the seas. Shortly after several years of an uneasy peace, international politics and technological innovations applicable to ships, submarines, aircraft, and weapons collectively brought additional high priority Navy requirements for knowledge about the sea. Answers were found in the expanding multidisciplinary field of oceanography. At this time, the number of people trained to be oceanographers was limited. Oceanography was growing and the Navy supported its development.

In the last half of the 20111 Century, the Korean, Vietnam, and escalating Cold War deepened the important relationship between the Navy and the oceanographic community. During this time, oceanography grew in importance to the Navy. Last century project names such as AMOS, CAESAR, CROSSROADS, HEARLD, LOFAR, JEZEBEL, SOFAR and SOSUS are some examples of Navy-Oceanographic joint efforts. In addition to in-house Navy laboratories, private oceanographic laboratories and university support, the role of industrial activities in the implementation of these projects was significant.

Oceanographic Needs

World War I (WWI) and the introduction of successful submarine operations especially by the German U-boats against navies and merchant shipping initiated a strong interest in the characteristics of the sea below in pursuit of sound detection as a potential weapon against the submarine. The surface ships pursuing the submarine and the submarine in search of targets needed the then-unknown characteristics of the seas and the paths of sound in the sea.

Mutual trust and understanding between the marine scientists and the Navy grew throughout the century but not rapidly. A time line of the relationship shows a gradual increase in joint efforts during the 1920s and 30s, a huge common effort during WWII with an adjustment period during the immediate postwar years. By mid-20th century, the body of knowledge about the ocean’s characteristics was no longer fragmentary and a scientific discipline known as oceanography was developing. Then in 1954 the nuclear submarine, new high technology weapons, and international tensions, Cold War, and Vietnam War brought increased Navy need for oceanography.

World War I (1914-18)
The enormous success of the German U-boat throughout the war established the submarine as a successful weapon in several regards. The submarines were small in size and crew requirements and effective. In February 1917, with 150 U-boats and unrestricted warfare, the Germans were sinking one of every four merchant ships leaving England. As the war ended, there was no assured counter-measure for submarines. In 1917, the depth charge, the convoy
system, the mine and seamanship were the basis for antisubmarine warfare (ASW).

In 1915, George Ellery Hale a member of the National Academy of Sciences (NAS), recognized the significant success of the German U-boats. To accelerate antisubmarine warfare effort in the United States, then a noncombatant, with President Wilson’s approval, Hale set up a partnership between science and industry in the military that accelerated the antisubmarine warfare effort.

To facilitate this, NAS in June 1916 established the National Research Council (NRC). For the first time, the Council brought scientists and engineers from industry and academia to address a broad array of challenges related to upgrading military preparedness prior to and following the April 1917 entry of the United States in the war. On May 11, 1918, President Wilson signed an executive order providing for the Council’s perpetuation in peacetime.

The NRC, from its inception, continuously backed Navy underwater interests in a variety of ways. Through the years, this assistance came primarily in the form of a respected and listened-to scientific voice in the Washington arena where Congressional fiscal support for science-related work was frequently critical. During the mid-1920s, NRC’ s science support was helpful. The NRC organized according to fields of science, not around the administrative and scientific problems of government.13 Navy oceanographic needs found positive support from the Council for the rest of the 20th century. The NRC has been referred to as the operating arm of the NAS.

Wartime antisubmarine research and experience pointed to further investigation of underwater sound as a tool for detection of enemy submarines. The need for more accurate data about the sea was required.

Interwar Years
In the 1920s, government agency support for marine science usually had an applied practical aspect: safety at sea, making maps, and the needs of the fishing industry. Privately supported marine scientists’ orientation was in basic research. Modest post- WWI interest stemmed in part from the successful U-boat performance mentioned above and the realization that detailed knowledge about the sea environment was lacking. Primary Navy interest was in underwater detection of enemy submarines. In addition to federal involvement, support for marine research came from business, private sources, and academic interest. The 1920s were also marked by a significant reduction in federal funding following the end of the war. Historically, it is almost a tradition to reduce military funding following the end of a war.

During the 1920s and 1930s, work related to the Navy’s continuing interest in the underwater detection of enemy submarines was at the newly constructed ( 1923) Naval Research Laboratory (NRL) in Anacostia, Maryland and the Submarine Signal Company of Boston. The work started during WWI on radio signaling and submarine detection provided a basis for NRL’s primary mission to perform applied research and support naval operations. The scientists and technicians who worked there were primarily civilians.

Between the World Wars, three important nautical instruments were introduced. Each device provided new information about the seas. Sound detection and echo ranging equipment required extensive knowledge regarding the propagation of sound in the sea. The Navy began cooperative work with oceanographic institutions.

Major New Devices
Detection equipment performance gradually revealed the impact of the various properties of the sea, sea life and topography on system performance. For the Navy, particular oceanographic knowledge was a prerequisite for best operational use of the evolving equipment.

The U.S. Navy’s WWII operational requirements around the world for surface ships, submarines, and naval aircraft (weather) created extensive and time critical need for expanded oceanographic assistance. This wartime oceanographic support provided by the scientists contributed significantly to naval victory during the four-year war.

During WWII, system development and implementation were heavily influenced by important participation by physicists and oceanographic (marine science) personnel. Marine scientists participation included going to sea on Navy as well as laboratory ships in addition to laboratory effort. In the post-war era, both professions were heavily pursued and the number of universities offering marine science and related fields of study increased.

New Instrumentation
Successful U-boat operation during WWI against the merchant and naval shipping encouraged continued investigation of submarine detection using sound. Results of testing the newly developed equipment pointed towards oceanographic investigation to find answers to problems having to do with attenuation of sound in seawater and other related topics. The surface ships pursuing the enemy submarine and the submarine in search of targets required more information about the then-unknown characteristics of the seas and the paths of sound in the ocean.

Sonic Depth Finder (Fathometer)
The Fathometer and the BT contributed to the collection of data about the sea. The efficiency of data collection and the amount of data collected was improved by orders of magnitude. Measuring the depth of the ocean was always demanding and labor intensive and the measurement of great depths not always feasible.

The 1920 device for depth measurement had its beginnings in a 1913 acoustic oscillator patent application by Reginald A. Fessenden.

In 1914, Fessenden installed his oscillator on the United States Revenue cutter MIAMI while on the first International Iceberg Patrol operating on the Grand Banks off Newfoundland, Canada. The oscillator was suspended underwater from the side of MIAMI and for three hours successfully received underwater echoes from an iceberg 430 feet long and 130 feet high.

Harvey C. Hayes
Hayes, a physics professor from Swarthmore College, developed underwater submarine detection equipment during WWI at the NRC’s Fort Trumbull laboratory at New London, Connecticut (1917-18). When WWI ended, he continued his investigations, initially at the Annapolis, Maryland Naval Engineering Experiment Station and then, in 1923, at the new Navy Research Laboratory (NRL) in Anacostia, Maryland.

In 1922, at Annapolis, Hayes developed a sonic depth finder (SDF) based on his work in 1918 at New London, CT. The sound source for the echo ranging was a Fessenden 540 Hz oscillator developed and demonstrated earlier in 1914. An MV hydrophone, invented by Max Mason at New London during WWI, was used for reception. The MV is a non-electric binaural listening system. The Hayes depth finder also included a timing device to determine the time interval; from that the distance from the source to the target could be determined.

Depth finder performance was further enhanced by the tables Hayes developed to assist the depth finder operator to quickly determine the depth from the observed data. “A single deep-ocean sounding with line and sinker had taken a better part of a day: with the Hayes Sonic Depth Finder sounding could be executed in a minute.” The finder evolved into the Fathometer patented and manufactured by the Submarine Signal Company of Boston. Within a few years, Fathometers were widely used by merchant shipping and navies. By 1929, the U.S. Hydrographic Office received daily reports of deep-sea soundings.

During the period June 22-29, 1922, on board the destroyer U.S.S. STEW ART (DD224), equipped with a Navy SDF, Hayes made the first continuous profile of 900 deep-sea soundings to depths greater than 3000 feet, 19 across the entire ocean basin from Newport, Rhode Island, to the Azores, and then to Gibraltar. Hayes left the destroyer at Gibraltar. Next, without interfering with its routine, the destroyer continued on to China Station, taking a total of 6500 nautical miles of continuous soundings.

The ease of the sonic soundings by the STEWART, contrasting with an earlier effort by the HMS CHALLENGER using line and sinker demonstrates the huge advantage of the Hayes equipment. The marine exploration vessel HMS CHALLENGER, in a cruise of about four years (1872-76) made 300 soundings every 100 miles using line and sinker. The STEW ART’s rapid profiling introduced a new dimension in gathering data about the ocean depths. At the 1904 VIII International Geophysical Congress in Washington, DC a sound chart plotted 18,400 points; by 1932 the number was 370,000.

The Fathometer, in addition to much improved efficiency in measuring depth, provided a way to reveal the undersea contours and greatly helped the underwater cable laying industry, reducing cable slack required by half. Before WWII, private marine scientists using fathometers to investigate submarine topography and marine geological processes found financial support from petroleum companies.

Hayes Memorandum
Hayes, aware of the decreased fiscal support for the Navy following the end of WWI, felt strongly that congressional support for NRL was critical for continuing his wartime research in the use of underwater sound to detect enemy submarines. He addressed these issues in a February 19, 1923 memorandum citing the value of oceanographic research to advance maritime safety and naval operations. He cited the political, economic and scientific value of oceanography.23 Along with scientists from other government agencies, Hayes made an effort to establish an oceanographic office within the Navy but failed for lack of financial support.

With his status as a scientist, his recent development of the SDF followed by his at-sea depth measurements made his memorandum credible. Hayes clearly pointed out the value to the Navy of more science orientation and a convivial approach to the marine science community members to work jointly towards common goals. White the memorandum did not result in the creation of an oceanographic office, it did have beneficial effects. Congressional and public awareness to the Navy and marine science was raised. In August 1923, U.S. Navy participation in a Pan-Pacific Science Congress in Australia included sending the new light cruiser MILWAUKEE (CLS), using the SDF en route, to make a series of ocean bottom profiles and to present the findings at the Congress.

The following year, under the aegis of the NRC and others, a federal Interagency Conference on Oceanography was held to determine the nature of naval commitment to oceanographic research for the next two decades. The planning included a positive attitude toward cooperative oceanographic work with the Navy by the private oceanographic sector.

An increase in joint civilian and Navy oceanic research followed this heightened awareness about marine science, but it did not grow rapidly until WWII and beyond. Basic sea research with modest fiscal support during the interwar years provided useful information about the performance of underwater detection equipment. In some of the areas researched, including salinity, hydrostatic pressure, turbulence, air bubbles, and temperature gradients, knowledge grew.26 The global scale of the coming war quickly indicated the importance of oceanography and the operational needs of the military that included more than the underwater detection requirements.

Navy-Princeton Gravity Expedition 1932
At that time, there was interest in making gravity measurements at sea to increase knowledge about the earth’s underlying structure. A submarine was suitable for the instrumentation available to make measurements. Measurements from surface craft were hampered by surface wave action. The Navy provided the submarine S48 for six weeks of measurements from February 7 to March 17, 1932. With civilian scientists aboard, gravity measurements were made in the region of the West Indies. Submarine gravity measurements at depths in excess of 100 feet used a gimbaled multiple pendulum device gravimeter. Submarine gravimeters were in use from 1923-1950. Hyman Rickover on a three-year tour was the executive officer and navigator. By mid century, surface ship equipment for gravity subsurface measurements was available.

Later in the century with underwater missile launches aimed at targets thousands of miles away, gravity variations assumed significant importance. “Knowing gravity variations helps a submarine stay on course when it is underwater and sailing blind, and when the time comes to launch a missile . .. that knowledge is essential.

1936-37 Crucial Oceanographic Events

Understanding how the ocean moves and mixes heat requires accurate and continuous measurements of temperature as it changes with depth. With this in mind, in the summer of 1934, Carl Rosby a summer resident of Woods Hole and Massachusetts Institute of Technology (MIT) meteorologist, constructed and took to sea aboard the Atlantis (the Woods Hole oceanographic research vessel) a boxlike structure, an oceanograph, designed to record continuous tracings of temperature versus depth in the surface layers of the ocean. The objective was to be an improvement over the current methods for measurement.

The device consisted of a compressible bellows with a pen arm and a stylus at one end. The stylus moved horizontally to temperature changes and rested on a smoked-glass slide recording the changes. Vertical stylus movement recorded depth. 30 Rosby gave the device to Athelstan Spilhaus at MIT to redesign. By 1937, a Spilhaus-patented prototype called a bathythermograph (BT) was available to go aboard the ATLANTIS.

The BT soon evolved into an important device for surface ships seeking enemy submarines and equally desirable for submarines in avoiding detection. Thousands were manufactured during WWII. They were classified secret for some period after the end of the war.

In late 1936, SEMMES (a 1919 destroyer) was converted to a research and experimental sound vessel attached to the Navy Research Laboratory. It was equipped with highly classified underwater sound echo-ranging gear (sonar) and working with a submarine out of Guantanamo Bay Naval Base in Cuba. An abnormal operating condition with the equipment was encountered. The equipment worked well every morning. Later in the day, with the Semmes steaming right over the target submarine no detection was made. When the Semmes returned to New London, Connecticut (the ship’s homeport), Lieutenant William Pryor of the Semmes took the problem to the director of WHO!. The Institute was interested and arranged to conduct almost two weeks of joint testing with the Semmes, the Atlantis, and a submarine early in 1937 near Guantanamo, Cuba. Additional tests were made following August off Long Island. Institute underwater sound and submarine detection experiments continued into 1940.

Columbus Iselin, the assistant director at WHOI, participated in the test and his conclusions were seminal. He put forward that the sonar problem stemmed from the way sound traveled through water and the layers of cooler and warmer water near the surface caused bending and distortion of the sound beam. The phenomenon was called “afternoon effect.” The about-to-be patented and improving BT with the capability to provide a record of the depth and temperature certainly loomed on the horizon as an important tool to assist the submarine hunter (the surface ship) and the target submarine to successfully hide from the searching hunter. Research pointed to temperature and pressure as two main variables influencing underwater sound transmission.

A noteworthy aspect of this 1937 successful cooperative venture by the Navy and Woods Hole laboratory was that it marked the beginning of a continuing relationship between the Navy and the marine science community as it grew in the years leading up to WWII. The Navy considered water temperature of the upper layers critical information. By 1940, expedited and expanded effort vastly improved the BT for use from moving surf ace ships and later for use on submarines.

Maurice Ewing
On October 17, 1937, geophysics professor Ewing from Lehigh University joined Columbus Iselin aboard the ATLANTIS for a test cruise. His interest was to conduct seismic refraction experiments to determine the thickness and makeup of sediments at the ocean bottom at depths of three miles in the North Atlantic. He used underwater explosives ( 10 pound TNT blocks) as sound sources and noted that a chain of echoes was generated by repeated reflections between the ocean bottom and the sea surface especially at the lower frequencies and traveled long distance underwater with limited loss. Further, if hydrophones were carefully located in this deep sound channel the signals could be detected. Important implementation of this channel identification followed but not immediately

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