The real measure of the fire situation in bone-dry California is that forestry officials here acknowledge routinely that the Marble Cone fire in the Big Sur area is likely to burn until mid-October.

By today Marble Cone had consumed 92,200 acres and destroyed both remote brushlands and valuable watershed area near the Carmel River. Firefighting officials in the interagency command center here said that it is likely to destroy at least 170,000 acres before it is contained.

"The fire will double in size," predicted Howard Koskella, the U.S. Forest Service coordinator at the command center. "Even after we contain it within fire lines, it's going to continue burning within them until the first rains fall."

Both August and September are usually rainless months in California. Koskella said that the long-range weather forecast, admittedly an imprecise tool, does not call for any rain before Oct. 14.

Despite the advance of the Marble Cone fire and the continued rainless forecasts, there is an almost optimistic atmosphere in this command post, which has been operating on a round-the-clock basis since July 25. Many of the federal and state officials here are veterans of a 13-day fire siege in 1970, the worst in California's recorded history when wind-whipped blazes ranginf from Oakland to the Mexican border destroyed 576,000 acres of forests and rangeland.

"If we had winds now, the Marble Cone fire would be five times worse," said Clinton B. Phillips, Koskella's opposite number from the California Department of Forestry.

As it is, Marble Cone promises to become the third biggest forest fire in the state's history. The worst was a blaze known as the Matilija Fire, which burned 219,000 acres in a remote area of the Los Padres National Forest in 1932. Most of Marble Cone is burning in another part of Los Padres, nearer the coast and the inhabited areas of Monterey and Carmel.

Because of the location of Marble Cone, its impact is potentially more serious than Matilija. State officials fear the denuded hillsides are likely to pose flood damage threats for Carmel Valley and Big Sur residents when the rains ultimately arrive.

The second-biggest fire was the Laguna Fire in San Diego County in 1970, the largest single blaze of the wind-driven fires that consumed so much rangeland that year. This fire blackened 175,000 acres.

The interagency command center had stripped bare the firefighting capabilities in this region to send crews to Marble Cone and to Scarface, a major blaze in northeastern California.

Scarface and four lesser but damaging blazes in the same area were near control today, and only Marble Cone remained as a major trouble spot.

Both the state and federal forestry services operate on the theory that 97 per cent of fires should be controlled before they have burned 10 acres. But the drought has made this standard an impossible one to achieve.

"The other day [Tuesday] a fire started along the freeway heading from Lake Tahoe to Reno," said Koskella. "We were able to drive our equipment right up to it. Still, it burned 800 acres and to the top of a mountain before we could get it under control. It was just so dry we couldn't stop it."

Scarface, after burning 82,000 acres, was brought near containment with the help of experienced smoke jumpers. But this technique could not be used at Marble Cone because there was no safe place from which to extricate the jumpers once they were sent in.

"We'd have been sending the jumpers to a flammable death," said Koskella.