Beginner question

It's been half a century since I needed the information, so I'm not
sure. Is a nineteen-inch bicycle frame nineteen inches from the
center of the bottom bracket to the center of the seat cluster?
"Center" defined as the middle of the top tube.

I measured my Fuji at 20.5 inches, and the guy I stole it from said
"twenty-one inches" sounded familiar.

To the top of the top tube seems more logical, since it's the
stand-over height one is interested in -- a fat-tube aluminum bike
would measure undersized if measured to the middle.

When I was thirty and forty and sixty I didn't mind that he's an inch
taller than me, but now that I'm seventy-nine, I've fallen over while
mounting twice, and think it's time to put the word out that I'm in
the market for an elderly bike that is compatible with my elderly
components.

But I have to say what size I want.

--
Joy Beeson
joy beeson at comcast dot net
http://wlweather.net/PAGEJOY/