Former president Lyndon B. Johnson received "envelopes stuffed with cash" while he was vice president, according to an excerpt from a forthcoming biography by Pulitzer Prize-winning author Robert Caro. The accounts were published in the current Atlantic magazine.

Johnson "threw himself into the pursuit of wealth with a furious, frenzied, almost desperate energy" that also characterized other areas of his work, Caro writes in the introduction to his book.

Former Johnson aides reached yesterday refused comment on the allegations. George Christian, press secretary for Johnson for three years of his presidency, said, "Obviously I never knew of any such thing."

Caro writes that "Fifty thousand dollars (in $100 bills in sealed envelopes) was what one lobbyist--for one oil company--testified that he brought to Johnson's office during his term as vice president."

When asked yesterday about his sources, Caro said he had written thousands of pages and gathered massive amounts of evidence from numerous sources and could not summarize the book's evidence in a few sentences.

He said, however, that the $50,000 incident referred to lobbyist Claude C. Wild Jr., who had testifed in a case brought by the Securites and Exchange Commission against Gulf Oil in the mid 1970s about a Gulf Oil slush fund. Caro said he thought the transaction occurred in 1963.

Newspaper stories from the period report that Wild said he gave $50,000 to a Johnson aide while the former president was a senator to help Johnson's 1960 bid for the presidency. In 1978 Wild admitted in a sworn statement that as a Washington employe for Gulf Oil Co. he had given up to $4 million in company funds to federal, state and local politicians.

Caro's article contains few other details of Johnson's financial affairs although the author said yesterday that later excerpts would have more information.

Fully documented details will be in the book when it comes out, he said. So far only one 600,000-word volume of the three-part work has been written, Caro said.

"More significant than the dollar totals of Lyndon Johnson's fortune were the methods he employed to accumulate it," Caro writes in the introduction to the Atlantic article. "A detailed examination of such methods is an instructive lesson in the means by which, in 20th century America, a position of public power can be used to accumulate private wealth."

Johnson "piled atop the millions of dollars he had already made millions more" while president, Caro writes. The "new economic forces--oil, gas, sulfur, defense, space and other new industries of the Southwest--raised him to power and, once he was in power, helped him to extend it," Caro reports.

When interviewed yesterday the author said he thought it was of key importance to "examine the way these new economic forces of the Southwest use raw economic power to reshape the domestic policy of the United States."

Johnson is portrayed as a man of ambition, greed and complexity, who worked extremely hard to learn his way around Washington and Congress when a young congressional aide and congressman. "No one knew him . . . no one saw him whole," Caro writes, "not his wife . . . not his mother."

The blind trust set up by Johnson when he became president in 1963 to handle his financial affairs was "a mockery," Caro claims. "The establishment of the trust was virtually simultaneous with the installation in the Oval Office of private telephone lines to certain Texas attorneys associated with the administration of the trust--and over those lines, during the entire five years of his presidency, Johnson personally directed his business affairs, down to the most minute details."

Caro quotes these attorneys as saying that Johnson would sometimes work on his private business affairs for several hours a day. "In his direction of his business affairs, he did not hesitate to use the power of the presidency itself, and to use it with utter ruthlessness," Caro says.