Hopper and Fonda went looking for adventure and whatever else would come their way on their epic cross-country odyssey. Borat set out to find the heart and soul of America, plus any part of Pamela Anderson he could get his hands on. Jeff Deck and Benjamin Herson have a different objective in mind as they motor across the country this spring in their '97 Nissan Sentra.

They chase the misplaced apostrophe, the disagreeing subject and verb.

The horror (as opposed to "horor") of a courthouse sign, engraved and erected at taxpayer expense, omitting the first "o" in "meteorological." The "desserts" unjustly advertised as "deserts" on a restaurant wall.

They seek, in short, to do for America's public signage what spell-check software has done for interoffice e-mail: smarten it up and make it easier on the eye. Their weapons: Wite-Out, markers, ink pens, tape, and nerves of steel.

"I figured, Steinbeck had his dog and Kerouac had his drugs. I'd have my typos," said the 28-year-old Deck of what he calls his Typo Hunt Across America tour.

Deck, speaking by phone from somewhere in the Deep South as he and Herson rumble westward, says the point of the trip isn't to wag fingers at those who commit or ignore signage errata. It's to raise public awareness around an issue - a plague, really - that typically elicits a blank stare or shoulder shrug, if that.

"We're not going after people in a self-righteous manner, like fashion police. Or trying to make them look stupid," Deck said. "Instead, we're addressing specific errors like confusing 'its' for 'it's' or 'you're" for 'your.' Finding and correcting these, even every once in a while, is incredibly satisfying."

Deck left Somerville on March 5 and picked up Herson in Maryland, a few stops down the road. Since hitting the highway, they've put many hundreds of miles on the Sentra getting to such places as Hoboken, N.J.; Lansdowne, Pa.; Silver Spring, Md.; Virginia Beach, Va.; Morehead City, N.C.; Charleston, S.C.; Atlanta; Mobile, Ala.; New Orleans; Galveston, Texas; Albuquerque; and Flagstaff, Ariz.

Typo-correction kit in hand, they've targeted signs at shopping malls, banks, parks, and roadside cafes, among other venues. Errors of logic ("NO REFUND or NO EXCHANGE on any SEASONAL or SALE ITEM"), agreement ("Referred to as the 'Golden Apple,' lemons flavor and preserve foods . . ."), spelling ("Cakes for All Occassions"), and punctuation ("Cars will be towed at owners expense") have been identified and, in dozens of cases, corrected to proper English.

When confronted, store managers and other respondents have been good-natured about it, Deck said. For the most part.

"There's been no manhandling or fisticuffs, at least not yet," he said. Sometimes, he added, "when a typo is literally or figuratively out of reach, like behind a locked, chain link fence, there's nothing you can do about it anyway."