Along the same line, jb...

An elderly lady walked in the local pub and sat at the bar. "Ill have scotch, with three drops of water." The bartender asked "What are you celebrating", and she replied, "I'm 92 today!"
"Well that's a reason to celebrate! Let me buy you a round - in fact I'll buy this one!" As she finished her drink, the fellow to her left said, "Did I hear it's your birthday? I'd like to buy you a drink, too"
"I'll have scotch with three drops of water", she said to the bartender. Again, as she finished her drink another of the regulars called over to the bartender, "I'll buy the birthday girl a round!"
"I'll have scotch with three drops of water". As she was enjoying her third drink the bartender strolled over, "I'm curious, why are you so specific about only three drops of water in your scotch?"

"Well, sonny. At my age I can hold my liquor, but holding my water is a different story!!"