Science Experiment gone very wrong ...

You thought your kid(s) gave you a rough time today? Here's my afternoon ...
So, during "rest time" today while the kids were supposedly sleeping, I took the monitors outside so I could get some garden work done. I started to come inside to get some flour to mark an area to dig when I saw Thomas. I knew he had been playing (at first) but he does that frequently, then falls asleep. I opened the door to walk in and I heard water running - *lots* of water. I ran into the bathroom thinking the toilet was overflowing - and saw water dripping from the ceiling. Uh-oh! I ran upstairs, slipping in the hallway where there was also water dripped through, and found the bathtub completely overflowing(!) I couldn't get ahold of ANY of my peeps - not Clay, not Rob, not my dad, not Clay's dad, and *finally* talked to my mom but she had no idea what to recommend for cleanup! Gah! I sent Thomas to his room, started mopping up what I could with towels, and the phone rang. It was Rob, who went searching for Clay for me - apparently I was doing just what I should, thankfully. Their first reaction was "Is Thomas ok?" Which, OMG, I hadn't even thought of (since I had seen him before ever hearing the water). But seriously - what if, what if, what if?!
Apparently this was all a science experiment - Thomas wanted to know what happens when the bathtub fills all the way up (!), and then decided he wanted *me* to turn off the water (he couldn't figure it out) but got distracted and started playing rather than coming to *tell* me I was needed ...
It was a long day.