U.S. 10-year Treasuries gained a third day on speculation central banks will fail to restore confidence to financial markets and keep economic growth from slowing. Government debt also rose as Morgan Stanley, the second- biggest U.S. securities firm, reported a fourth-quarter loss after a $9.4 billion writedown on mortgage-related investments. The Federal Reserve will announce at 10 a.m. New York time the result of an auction of $20 billion of one-month funds intended to revive credit markets after subprime losses made banks wary of lending to each other. The European Central Bank injected an unprecedented $500 billion into the banking system yesterday to ease a gridlock in money markets. The Fed will hold a second auction tomorrow, of as much as $20 billion. U.S. mortgage applications fell last week by the most since 2004.