In his ground-breaking 1922 documentary, "Nanook of the North," Robert J. Flaherty's black and white depiction of a year in the life of a group of Eskimos and their "fight for existence in the dramatically barren North," the explorer turned filmmaker included a segment on the construction of an igloo.

He described it this way:

"Using an ivory knife, they cut out blocks of snow and start a circular wall, laying the blocks spirally, and making each turn more restricted than the one below, somewhat similar to a snail shell.

"When the igloo is finished, a small hole is punched in the roof for the escape of heated air. A door is cut in the side, the chinks are closed with snow -- perhaps a window of ice is added -- and the habitation is complete."

Although igloos are used primarily as temporary shelters, blocks of snow can be used as a wind break for more traditional shelters.

Nanook, a variation of Nanuq in Inuit mythology, was the master of bears. It was he who decided if hunters had followed all applicable customs in their quest for bears.

After lugging his gear more than 800 miles by canoe and schooner, Flaherty set up shop in a fur-trading post at Cape Dufferin on northeastern Hudson Bay. He used one of the two rooms in the post as his combination living quarters and film lab.

His equipment included 75,000 feet of film, a Haulberg electric light plant and projector and two Akeley cameras and a printing machine. The latter enabled him to make prints of the film as it was exposed and project the pictures on a screen so the Eskimos could see what he was doing.

After conferring with post personnel as to who among the local Eskimos might help him with his film, Flaherty selected a man he described as "a character famous in the country" who had a long first name that was difficult to pronounce. He decided to call the man Nanook and the rest is cinematic history.

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