One story goes that Thomas Edison assigned a simple task to a newly
hired engineer - calculate the volume of a light bulb. The newbie
measured the bulb at the points he felt were critical and spent the
afternoon calculating the volume. Edison looked at the numbers and
said "You're off by at least 10%". Edison then took the light bulb,
drilled a little hole in it, filled it with water, then drained the
water into a graduated cylinder. And showed the engineer his numbers
were off by 10%.

But Edison measured the inside volume. The engineer calculated the
outside volume. To proof this, the engineer submerges the light bulb
and measured the water rise.
To prove his measurement he measured the force to keep it submerged.

So he proved that Edison was wrong.
The glass of the bulbs in those times was very thick.


You're missing the point of the story. There are ways to measure things that
are quick and elegant -- rather than applying a brute-force approach.