Sailing in Vincennes and Porpoise, he explored 1,500 miles of coast along the edge of the Antarctic ice pack south of Australia, while Peacock and Flying Fish cruised southwestward, in the area of Thurston Island.

From his observations, Wilkes concluded that Antarctica was a continent rather than a series of islands. Although many scientists disputed his ideas at the time, Wilkes has been proven correct by modern aerial mapping techniques.

During the final two years of the cruise, the expedition surveyed broad areas of the Pacific Ocean.

First Grinnell Expedition - Edwin DeHaven, 1850-51

Samuel P. Griffen was second in command and captain of Rescue, one of two ships purchased by Grinnell and turned over to the Navy for the expedition. DeHaven explored Lancaster Sound and Wellington Channel and found one of Franklin's camps but no trace of the men.

Second Grinnell Expedition - Dr. Elisah Kent Kane 1853-55

Although the first expedition had failed, Grinnell asked Dr. Elisha Kent Kane to lead a second attempt. The Navy surgeon had become famous on the previous expedition with DeHaven.

In 1853 Dr. Kane sailed from New York in the brig Advance. Hoping to discover an open ocean at the North Pole, he took his ships so far north that it became frozen in the ice. In 1855, after two years imprisoned by the ice, Dr. Kane led his party on a three-month trek over 1,300 miles of Arctic wasteland to safety in one of the most remarkable journeys in the history of Arctic exploration.

n. The expedition abandoned ship and dragged boats and sledges across the ice. On reaching open water, they launched a whale boat and two cutters. Although separated in a gale, they all reached the Siberian coast. Chief Engineer George W. Melville and his crew in the whaleboat were met by natives and were saved. The cutter landed and made camp on the Lena River, but the crews died of exposure and starvation. Melville stayed in the Arctic an additional year to search for DeLong and eventually found his last camp.

As others before him, Greely hoped his party might reach the North Pole. In this he failed, though two men reached a point farther north than any before them, but were forced by exhaustion to turn back.

The camp prospered, but in the summers of 1882 and 1883 boded ill, when the supply ships, blocked by ice, failed to reach them.

In august 1883 Greely decided to lead his party south to a food cache left at Cape Sabine where rescue would be more likely. The 500 mile trek sapped their energy, and the lack of enough food at Cape Sabine resulted in slow starvation.

On the eve of their rescue, the party was reduced to eating sealskin, sleeping bag covers, and boot soles. One man had been executed for stealing food.

Meanwhile, Thetis, a three-masted steam whaler built in 1881, was purchased by the Navy for the rescue attempt. Under the command of Cdr. Winfield Scott Schley, the ship sailed from New York on 1 May 1884 with Bear, commanded by Lt. William H. Emory. They found several caches left for Greely's party. Finally seven survivors of the 26-man party were located on 22 June.

The 42 man party wintered over, and in October 1929, began final preparations for the historical fight.

On 28 November, Byrd, with chief pilot Bernt Balchen, co-pilot Harold June, and photographer Ashley McKinley, took off from Little America in the Ford Trimotor named "Floyd Bennett" and flew up over the Liv Glacier to the 9,000 foot high polar ice cap. They circled the Pole taking pictures and then returned safely to Little America.

The expedition left Antarctica in February 1930 and returned home to wild acclaim in the United States and throughout the world. After a lapse of 90 years since the Wilkes Expedition, American interest in the Antarctic was rekindled by Byrd's historic feat.

Late in March 1934, Byrd flew to his base which he named "Bolling" in honor of his mother's family to begin his solitary stay over the Antarctic winter. However, poor eating habits and slow poisoning by the fumes of his stove and generator gradually weakened him to the point that a three man party set out to rescue him in early august. The four men spent the rest of the winter in the hut, continuing the weather observations and nursing Byrd back to health. Finally Byrd was airlifted back to Little America in October and the expedition began preparations for the return to the United States in the spring of 1935.

The ambitious program of surveying and scientific observations provided valuable training for a cadre of polar explorers who have helped maintain an American presence in the Antarctic to the present day.

The prefabricated hut, made of wood with special paper insulation and a reflective covering on the inside, was buried in the snow to protect it from the wind. Access was provided through a trap door in part of the roof projecting out from the hut. The hut provided reasonable comfort when the stove was working properly, even when temperatures outside fell below -70F. However, because of the danger of carbon monoxide poisoning, the stove had to be turned off most of the time, and the temperature rapidly dropped below zero in the hut.

The expedition represented the culmination of support for Antarctic exploration which had been generated by two previous Byrd expeditions. Under the command of Richard Byrd, the Navy expedition consisted of two ships - the Bear of Oakland and the North Star - plus four aircraft carriers and 125 men. Two bases were established: West Base, commanded by Dr. Paul Siple, and East Base by Richard Black. In one series of experiments in West Base, Dr. Siple developed the now commonly used wind chill index. The expedition was intended to give the United States a permanent presence in Antarctica, but the coming of World War II forced the evacuation of bases in 1941.

The expedition made major scientific contributions and photographed much of the coast of Antarctica which had never been recorded before. Participating ships included Mount Olympus, the flagship; the supply ships Yancey and Merrick; the submarine Sennet; the Navy icebreaker Burton; the Coast Guard icebreaker North Wind; the seaplane tenders Pine Island and Currituck; the destroyers Henderson and Brownson; and the tankers Cacapon and Canisteo; and the aircraft carrier Philippine Sea.

Operation Windmill 1947-48

Operation Windmill, launched the next year, included two icebreakers, Edisto and Burton Island, and 5,000 men. The mission was similar to Highjump in that it trained personnel, tested equipment, reaffirmed American interest in the region and made scientific observations. The expedition established geodetic ground control points for the aerial photography taken during Highjump the previous season. The work contributed to the production of the first set of medium-scale maps of the coast of Wilkes Land and the Queen Mary coast.

Finn Ronne, a Norwegian by birth, was commissioned a U.S. Navy lieutenant in World War II and was later promoted to captain in the Naval Reserve.

In nine trips to the Antarctic, including the Second Byrd Expedition and the U.S. Antarctic Service Expedition, he had traveled by ski and dog sled some 3,600 miles - more than any other man in history.

The Antarctic Research Expedition of 1947, although partially supported by the Navy, was personally organized and led by Ronne. In exploring and mapping more than 250,000 square miles of new territory, Ronne was able to confirm that Antarctica is one continent.

The 23-man expedition included two women - Mrs. Finn Ronne and Mrs. Harry Darlington, the first women to winter over on the frozen continent.

Operation Deepfreeze was a plan to take geophysical observations at more than 1,000 stations all over the world. Included were 60 stations in Antarctica that were manned by 12 different nations. During Deepfreeze I (1955-56), the U.S. Navy set up two permanent bases: one at Little America on Kianan Bay, and the other at McMurdo Sound near Hut Point where Scott and camped on his first expedition in 1902. Deepfreeze II (1956-57) commanded by R. Adm. George J. Dufek deployed 12 ships and 3,000 men to do scientific work on the frozen continent.

Because of the success of Operation Deepfreeze, the United States decided to maintain permanent bases on Antarctica. In the Antarctic spring of each year, August and September, ships move south to resupply the bases and relieve the personal who have wintered over. By the following March, the Antarctic winter sets in and the party prepares to endure the wind, cold, and isolation of another winter at Antarctica. Today the Navy maintains a base, housed in a geodesic dome at the South Pole, and the air facility and research station at McMurdo. The U.S. Coast Guard operates two ice breakers during the summer months to allow Navy-chartered logistic ships to resupply the base.