WHEN his last program airs tomorrow night after a 30-year run, it's going to be hard to think of "The Tonight Show" apart from Johnny Carson. But actually it was something of a surprise when he officially took over as host from Jack Paar in 1962. Although Carson had been subbing long before that, there was lots of speculation about other likely candidates.
I remember concluding that Carson would be a good choice after I dropped by the set of "The Tonight Show" one evening during one of his substitute gigs. It was before air time, and he was rehearsing a typically inane sketch - made palatable by his expertly easy-going touch - about Sir Isaac Newton. To give Carson a chance to pantomime the idea of gravity popping into Newton's head, a bushel of apples was supposed to be poured onto the floor from above. Instead they were poured on top of Carson. But his c omic instincts turned the mishap into a big laugh among the crew and others on the set.
For that sprawling late-night format, it was exactly the kind of reflex needed - intuitive, casual, ready to pounce on anything promising a laugh. Carson had utilized "the look," his deadpan stare of mock disaster that serves him so well as an all-purpose remedy for trouble. If a gag flopped, Carson could get a laugh from the failure itself simply by using "the look."
It was all part of the chemistry that "Tonight" has historically depended on, and that has sustained Carson himself: a balance of show-business adrenaline and laid-back command that allows "Tonight" hosts to survive the years - especially in face of the merciless demands the show used to make. Carson's current one hour a night, four nights a week is challenging enough, but at one time the schedule was positively insane. Original host Steve Allen, then Paar, and for a few years Carson himself, had to do a n hour and three-quarters, five nights a week, live! Never mind how these hosts survived the decades. How did they survive one show?