Attn: David Oliver... I enjoyed your rising card review/history... being a fan of rising cards it was most appeciated.
I am amazed, and wonder how you knew about the deck Fred Kaps used?
BTW the magnet floated down, not up.
That deck was my invention, and was made for Fred. I made a couple of them, and my own one was taken apart to try to make something else.
The little motors were really hard to find, but Kaps found them in a small town in Holland. We only had a few.
The magnet would drop slowly in the oil, giving you the delay you wanted by timing how long you inverted the deck.
When it reached the bottom, the switch was an electronic "reed switch."
It was so simple it was scary... the reason I developed this was the fact that radio controlled versions were NOT 100% they could be started by interference, a radio nearby or a walkie talkie (which I had happen) that someone had on the same frequency. :)