When I was a boy the Dead Sea was only sick.

A typical George Burns one-liner, the joke hinges on a mock-literal “before/after” view of aging: if the Dead Sea is “dead” now, then in Burns’s childhood it must have been merely “sick.” The humor comes from treating a fixed geographic name as if it recorded a changing medical condition, and it also plays into Burns’s long-running comic persona as an exceptionally old man whose memories stretch back implausibly far. Like many Burns quips, it’s a compact way of exaggerating longevity while sounding casually observational, turning the passage of time into an absurd, memorable image.