April 8, 1984

A Surge in Inventories Manufacturers and merchants are restocking their warehouses and store shelves at a fast pace. Their willingness to increase inventories despite current high financing costs means they are confident they can sell these goods quickly and profitably. The buildup has been such that when the Government issues its report this Friday on February inventories, it will show a rise of at least eight-tenths of 1 percent, or double the January increase, said Edward E. Yardeni, chief economist at Prudential-Bache Securities Inc. Equally important, Mr. Yardeni noted, the inventory-sales ratio for February could rise to 1.33, from 1.30 in January. ''This means,'' he said, ''that many businesses are now more concerned about losing sales because of bare shelves than being caught with expensively financed goods, which was their costly experience during the recent recession.''

Americans working for the Central Intelligence Agency on a ship off Nicaragua's Pacific coast have been supervising the mining of Nicaraguan harbors in recent months, according to Reagan Administration officials and members of Congress. The sources say the mining operation marks the first time since the United States began supporting Nicaraguan rebels three years ago that Americans have become directly involved in military operations against Nicaragua. The actual placement of the mines inside Nicaraguan territorial waters, they said, is handled by an elite group of Latin American commandos who use small, high-speed boats to penetrate shipping lanes close to shore. 'Closer to Direct Confrontation' The officials said that unlike ground operations inside Nicaragua conducted by rebel forces, which American advisers monitor from Honduras but do not control, the planting of the mines in Nicaraguan waters directly involves Americans and is under their immediate control.

TRY to think of an office scene in a major modern American novel. Hemingway scarcely has one anywhere in his work. (He never used his famous brawl with Max Eastman in Maxwell Perkins's office as fictional material.) In ''The Grapes of Wrath'' and scores of other protest novels of the 1930's, the callous acts of bankers and businessmen are described, but we seldom see them committing the acts - or, in the case of ''The Grapes of Wrath,'' see them at all. In ''The Great Gatsby,'' Nick Carraway comes to the office of the racketeer Meyer Wolfsheim, only John Brooks , a staff writer for The New Yorker, is the author of two novels and much nonfiction about American business. to be rebuffed by a receptionist: '' 'You young men think you can force your way in here any time,' she scolded. 'We're getting sickantired of it. When I say he's in Chicago, he's in Chicago.' '' Wolfsheim does nevertheless appear and invites Nick into his office, but the ensuing conversation is entirely about why Wolfsheim can't go to Jay Gatsby's funeral. Carraway gets just about as close to actual business dealings (in this case, shady ones) as do most American fictional characters. When it comes to the moments that count from a business point of view, the door of the executive suite is usually closed.

The Rangers, who one week ago said that overcoming the Islanders would be an almost impossible mountain to climb, now stand only one victory from tossing the four-time Stanley Cup champions from the pinnacle of the National Hockey League. Led by Pierre Larouche's two goals, and another standout goaltending job by Glen Hanlon, the Rangers last night thrashed the Islanders, 7-2, at Madison Square Garden to take a 2-1 advantage in the three-of-five- game, opening-round playoff series. The series could end tonight in Game 4 at the Garden with a Ranger victory. Not since 1982, in a first-round series with the Pittsburgh Penguins, have the Islanders been in such a ''must-win'' situation. Since avoiding elimination that year, with a fifth- game victory over the Penguins, the Islanders have gone seven straight playoff series without entering a game in which they faced elimination.

Before any Oscars are handed out tomorrow night at the 56th annual Academy Awards, someone will walk out on stage and recite the voting rules. This tradition begain in 1970 when the FCC demanded it, and the Academy has gone out of its way ever since to get this part of the show over with fast. Last year, the actor John Moschitta breezed through it in 25 seconds - the length of one of his television commercials for a package delivery service. The Academy doesn't like to go into specifics about its membership, but every year when the nominations are released, surprising nominations and omissions raise questions about who is doing the voting. Many members of the Actors Branch, for example, haven't made a movie in decades. The Directors Branch, with Elaine May and Claudia Weill as its only female members, is virtually an exclusively male preserve. Who, in fact, are the 4,053 Academy voters and how do they vote? And do they all even bother to vote?