Track of the USS ENTERPRISE across the southern Pacific Ocean in 1885. At the time this line was run, it was the furthest south continuous east-west sounding line yet observed.

Profiles of Concepcion Bank and Seine Bank by Edward Stallibrass, a British telegraph engineer, as published in 1887 in "Deep-Sea Sounding in Connection with Submarine Telegraphy," Journal of the Society of Telegraph-Engineers and Electricians, Volume XVI, No. 68, pp. 478-521.

Maps of the track of the DACIA in 1883, the Bottomless Pit, and Congo Canyon, by Edward Stallibrass, a British telegraph engineer, as published in 1887 in "Deep-Sea Sounding in Connection with Submarine Telegraphy," Journal of the Society of Telegraph-Engineers and Electricians, Volume XVI, No. 68, pp. 478-521.

Map of the Congo Canyon as surveyed by the Cable Ship BUCCANEER, by Edward Stallibrass, a British telegraph engineer, as published in 1887 in "Deep-Sea Sounding in Connection with Submarine Telegraphy," Journal of the Society of Telegraph-Engineers and Electricians, Volume XVI, No. 68, pp. 478-521.

Map of the "Bottomless Pit" (a canyon) as surveyed by the Cable Ship BUCCANEER, by Edward Stallibrass, a British telegraph engineer, as published in 1887 in "Deep-Sea Sounding in Connection with Submarine Telegraphy," Journal of the Society of Telegraph-Engineers and Electricians, Volume XVI, No. 68, pp. 478-521.

Map of the track of the Cable Ship DACIA in 1883, showing Concepcion, Dacia, Seine, Josephine, and Gettysburg Banks, and Coral Patch, by Edward Stallibrass in "Deep-Sea Sounding in Connection with Submarine Telegraphy," Journal of the Society of Telegraph-Engineers and Electricians, Volume XVI, No. 68, pp. 478-521.

World map with ocean physiography published in 1887 in Appletons' American Standard Geographies Physical Geography , pp. 20-21. Note "Alaska Deep" and "Alaska Rise" off the coast of South America. These were discovered by George Belknap on the USS Alaska in 1882 and were the first published names for the Peru-Chile Trench and Chile Rise.

Atlantic Ocean as shown by John D. Quackenbos and William Healy Dall in: Appletons' American Standard Geographies Physical Geography , pp. 20-21. The Dolphin Rise was named for the USS DOLPHIN which first sounded on the Mid-Atlantic Ridge under Lieutenant Commanding Otway Berryman in 1853.

Indian Ocean and western Pacific Ocean as shown by John D. Quackenbos and William Healy Dall in: Appletons' American Standard Geographies Physical Geography , pp. 20-21. Note that Ninety East Ridge is missing and that the deepest depth yet observed up to 1887 was the TUSCARORA Deep in what we now call the Kuril Trench to the NE of Japan.

Sir John Murray's map of the Atlantic Ocean, Chart 1A, accompanying the Summary of Results of the Challenger Expedition, 1895.

Sir John Murray's map of the Indian Ocean, Chart 1C, accompanying the Summary of Results of the Challenger Expedition, 1895.

Sir John Murray's map of the Pacific Ocean, Chart 1B, accompanying the Summary of Results of the Challenger Expedition, 1895.

Section of North Pacific Ocean on Murray's map of the Pacific Ocean, Chart 1B, accompanying the Summary of Results of the Challenger Expedition, 1895.

Title page to George Davidson's "The Submerged Valleys of the Coast of California....", in Proceedings of the California Academy of Sciences, Third Series, Vol.1, No. 2. This paper documented Coast Survey discoveries of submarine canyons beginning with the first ever discovered, Hueneme Canyon, in 1855. Monterey Canyon was the second, discovered in 1857.

A map by Adolph Lindenkohl of the United States Coast and Geodetic Survey showing the specific gravity of the waters of the North Pacific Ocean. Published in Petermann's Geographische Mittheilungen in 1897.

Sir John Murray's world map of 1899, Atlantic Ocean. The only physiographic feature he named were deeps, defined as area of the seafloor believed to have depths greater than 3000 fathoms.

Sir John Murray's world map of 1899, Indian Ocean. The only physiographic feature he named were deeps, defined as area of the seafloor believed to have depths greater than 3000 fathoms.

Sir John Murray's world map of 1899, Pacific Ocean. The only physiographic feature he named were deeps, defined as area of the seafloor believed to have depths greater than 3000 fathoms.

Alexander Supan's world map of 1899 showing both deeps and bathymetric highs of the World Ocean. Note difference in names between Supan and Murray in previous map. Supan's naming methodology prevailed in the Twentieth Century. Note also the Karolinen Graben running parallel to the Caroline Islands as opposed to the correct orientation of the Mariana Trench.

Alexander Supan was among the first to recognize the nature of oceanic trenches. Compare his nomenclature for the Aleutian Trench to John Murray's 1899 map. Perhaps Supan Deep as shown by Murray was a little jab as Murray continued this sort of terminology until his untimely death in 1914.

A Russian map of the Barents Sea by L. Brietfuss and A. Smirnow published in 1905. Additions to soundings based on the expeditions of Willem Barentz and Karl Weyprecht.

A Russian map of the Barents Sea by L. Brietfuss and A. Smirnow published in 1905. Same map as the last.

Otto Krummel's map of the Mariana Trench. In: "Handbuch der Ozeanographie", 1907. This corrects the error made by Supan in his 1899 map which showed a Karolinen Trench running parallel to the north side of the Caroline Islands.

A map of Germany's western Pacific colonies as of 1910. The Mariana Trench and Tonga-Kermadec Trenches are shown clearly as are a few seamounts. The deepest spot on this map is now in the Mariana Trench, SE of Guam, with a depth of 9636 meters. The deepest point in the Mariana Trench is now know to be approximately 10,915 meters.

A 1912 map of the World Ocean by Sir John Murray. He published one more map prior to his death which still retained his use of personal names for major features of the world ocean and did not acknowledge the configuration of most trenches.

A 1912 map of the Atlantic Ocean by the German oceanographer Gerhard Schott. Note the use of the term Telegraph Plateau following the 1858 nomenclature of Maury. In: "Geographie des Atlantischen ozeans" by Gerhard Schott. Library Call No. GC481 .S34 1. Aufl. (1912) .

A 1912 map of the Atlantic Ocean by Max Groll. Although quite similar to Gerhard Schott's map, it is totally devoid of feature names. The number of included soundings, although providing evidence for the determination of contour lines, tends to obscure the overall pattern of seafloor features.

The northern half of the 1912 Atlantic Ocean map by Max Groll. In: Tiefenkarten der Ozeane mit Erlauterungen. Plate I, Atlantic Ocean.

A 1912 map of the Indian Ocean in Tiefenkarten der Ozeane mit Erlauterungen by Max Groll. Note the light-colored (shallower) area between Australia and Antarctica, an early indication of the continuity of the oceanic ridge system in the South Indian and South Pacific Oceans. Amazingly, a feature as large as Ninety East Ridge had yet to be discovered. Plate II, Indian Ocean.

A 1912 map of the Pacific Ocean in Tiefenkarten der Ozeane mit Erlauterungen by Max Groll. Note the light-colored (shallower) area in the vicinity of what is today called the East Pacific Rise, and early indication of the continuity of the oceanic ridge system. Plate III, Pacific Ocean.

Sir John Murray's map of the world ocean published in 1912. Murray stuck with his nomenclature and interpretation of features until his death. The German geographers were definitely ahead of the world in their understanding of the nature of the seafloor and our planet until the Second World War.

Sir John Murray's continuation of the naming of features for researchers even though they never worked in a given area. Supan had understood the nature of the Aleutian Trench and named it accordingly in 1899. Murray refused to acknowledge either the interpretation or the naming system proposed by Supan which has since been adopted by the world with minor modifications.

Gerhard Schott's 1912 map of the Arctic Basin and North Atlantic showing numerous distinct basins and, although first soundings on Reykjanes Ridge was probably on H.M.S. BULLDOG in 1860, this is among the first maps to show it as a named feature. In: Geographie des Atlantischen Ozeans by Gerhard Schott, 1912. P. 120.

An early profile of the Mid-Atlantic Ridge. In: Geographie des Atlantischen Ozeans by Gerhard Schott in 1912. P.88.

A map of the rugged topography around the Azores Islands produced by Gerhard Schott. This map gives an indication of the level of detail achievable with piano-wire sounding technology. Map VII, p. 112, Geographie des Atlantischen Ozeans by Gerhard Schott 1912. Library Call No. GC481.S4 1.Aufl. (1912).

An inset map of an area off the coast of Brazil, South America, showing numerous banks and seamounts. Probably most of these features were discovered by British Cable Ship operations. In: Geographie des Atlantischen Ozeans by Gerhard Schott in 1912. P.103.

An inset map of the Congo Canyon in: Geographie des Atlantischen Ozeans, by Gerhard Schott, 1912. P. 102.

A cross-sectional view of Hudson Canyon by Gerhard Schott in 1912. In: Geographie des Atlantischen Ozeans by Gerhard Schott in 1912. P. 109.

A map of the Atlantic Ocean off NW Africa, the same area covered by Edward Stallibrass in map00031, with tables showing the least depth and extent of the banks in square kilometers. In: Geographie des Atlantischen Ozeans by Gerhard Schott in 1912. P.111.

A map of the Atlantic Ocean off NW Africa, the same area covered by Edward Stallibrass in map00031. In: Geographie des Atlantischen Ozeans by Gerhard Schott, 1912. P. 111.

A profile view of Seine Bank in: Geographie des Atlantischen Ozeans by Gerhard Schott, 1912. It shows a flat-topped seamount, what we would today call a guyot. In fact, many of the seamounts discovered prior to the invention of the echo sounder were flat-topped seamounts having a wide surface area on the top increasing the probability of discovery by widely spaced piano-wire soundings.

This map used Sir John Murray's bathymetric map as the base map for a map of world vulcanism. Published in 1914 under the title "Oro-Bathygraphical Chart of the World." This was probably one of the last maps published using Sir John Murray's nomenclature and interpretation of the bathymetry of the seafloor.

The last of the Murray-Supan controversy over nomenclature as shown on this 1914 map titled Oro-Bathygraphical Chart of the World. Sir John Murray died in 1914 as the result of an automobile accident.

A 1925 map of the Russian sector of the Arctic Ocean showing discoveries made from 1911 to 1915 by Russian surveyors and explorers. This map was published as "The Russian Hydrographical Expedition to the Arctic" in The Geographical Review, Vol. XV, No. 3, 1925.

Map showing the route and profile of soundings obtained by the USS STEWART in 1922. The STEWART crossed the Atlantic and ran a complete line of acoustic soundings and obtained over 900 measurements of depth from the East Coast of the United States to the Straits of Gibraltar. Although not the first line of acoustic soundings, it ushered in the use of acoustics in ocean exploration.

The Atlantic Ocean in "Geographic das Atlantischen Ozeans", 1925, published by Gerhard Schott on the eve of the famous German METEOR Expedition in 1925. There are few, if any, substantive changes between this map and Schott's 1912 map. Most of the large features of the ocean floor had been discovered by the early 1900's. However, ocean scientists were on the edge of a new era of discovery.

The North Atlantic Ocean and Arctic Ocean in: "Geographic das Atlantischen Ozeans", 1925, published by Gerhard Schott. This was in the second edition of his work on Oceanography and basically showed that little additional knowledge of this area had been obtained since 1912. See image map00062.

This 3-dimensional view of the equatorial Atlantic seafloor was produced following the German METEOR Expedition of 1925-1927. Unfortunately it was destroyed during the Second World War but the image survives. The Mid-Atlantic Ridge snakes down the middle of the Atlantic Ocean between Brazil on the left and Africa on the right.

State of knowledge of the Southern Ocean in 1929 as compiled by the American Geographical Society.

"Echometre" record obtained by the French liner S.S. De Grasse when crossing over the head of a canyon on Georges Bank. Such records reinforced the view that vessels could navigate by using bathymetry. Accordingly, the United States Coast and Geodetic Survey embarked on a project to map the continental slopes and shelves to help guide mariners into United States ports.