Seagoon - Harry Secombe - was the essential 'point of sanity' around which the whole madness revolved - and even he had difficulty not breaking up at times. While 'Greenslade' is most often remembered as the 'straight announcer', Valentine Dyall - the deep 'horror voice' was IMO, a far better straight (and funnier - like Cleese in his 'straight man' roles) man...
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If you don't get this one - you must be American...

Bluebottle: What time is it Eccles?
Eccles: Err, just a minute. I've got it written down here on a piece of paper. A nice man wrote the time down for me this morning.
Bluebottle: Then why do you carry it around with you, Eccles?
Eccles: Well, if anybody asks me the time, I can show it to them.
Bluebottle: Wait a minute Eccles, my good man...
Eccles: What is it fellow?
Bluebottle: It's writted on this bit of paper, what is eight o'clock, is writted.
Eccles: I know that my good fellow. That's right. When I asked the fella to write it down, it was eight o'clock.
Bluebottle: Well then, supposing when somebody asks you the time, it isn't eight o'clock?
Eccles: Then I don't show it to them.
Bluebottle: Well how do you know when it's eight o'clock?
Eccles: I've got it written down on a piece of paper!

(the full routine continues, but I don't want to do a complete spoiler...)