Several of the Mensa members went out for lunch at a local café

Mensa, as you know, is a national organization for people who have an IQ of 140 or higher.
  
Several of the Mensa members went out for lunch at a local café. 
When they sat down, 1 of them discovered that the salt shaker contained pepper & the pepper shaker was full of salt.
  
How could they swap the contents of the 2 bottles without spilling any & using only the implements at hand?  Clearly this was a job for Mensa minds. 
  
The group debated the problem, presented ideas & finally came up with a brilliant solution involving a napkin, a straw & an empty saucer. 
  
They called the waitress over, ready to dazzle her with their solution. 

"Miss", they said," We couldn't help but notice that the pepper shaker contains salt & the salt shaker - " but before they could finish, the waitress interrupted, 
"Oh! sorry about that".  
  
She leaned over the table, unscrewed the caps of both bottles & switched them. 
  
There was dead silence at the Mensa table. 
  
Kinda' reminds ya' of Congress, doesn't it?

Thanks Kerry