Yet sleep scientist Ying-Hui Fu at the University of California, San Francisco,says little is known about the basic need for sleep.

VOA: special.2009.08.26

In return,he had to promise that the mail would travel from Saint Louis,Missouri, to San Francisco,California, in twenty-five days or less.

VOA: special.2010.04.26

The next day, the San Francisco Chronicle newspaper printed four words in French across the front of the paper.

VOA: special.2009.12.14

Many years later, after Emperor Norton's death, a bridge was built extending from San Francisco to the city of Oakland.

VOA: special.2009.12.14

Ms.Gass used cloth and paints to create an image of a water treatment center on the San Francisco Bay.

VOA: special.2011.06.15

A ship that sailed from New York to San Francisco had to travel around the bottom of South America.

VOA: special.2009.12.23

It had to keep moving to reach San Francisco in twenty-five days as required by the government contract.

VOA: special.2010.04.26

They do not want people in Frisco oops,make that San Francisco to forget the first and only emperor of the United States.

VOA: special.2009.12.14

From that time on, the San Francisco policemen showed respect to Joshua Norton by giving a military salute.

VOA: special.2009.12.14

He came off the ship Excelsior in San Francisco with one hundred thirty thousand dollars worth of gold.

VOA: special.2009.02.04

They include the New York Public Library, the Smithsonian American Art Museum in Washington,D.C., and the San Francisco Museum of Modern Art.

VOA: special.2009.08.28

So the stagecoach would travel south from Saint Louis to El Paso,Texas, then over to southern California, then north to San Francisco.

VOA: special.2010.04.26

Neil Risch is director of the University of California, San Francisco, Institute for Human Genetics and a leader of the new study.

VOA: special.2009.06.24

Then the opera will move on to Calgary,Canada and the California cities of San Diego and San Francisco.

VOA: special.2010.06.11