Picked this up from an old magic estate.
You receive the original envelope (toned from age), instructions, and special gimmick.
The original ad for this trick went like this:
Anti-Gravico is the greatest, most amazing magic trick of this type ever invented.
Positively practical, easy to do, and really mystifying. The newly added “stop and flow” features make it a still better magic feat.
EFFECT: A borrowed bottle, full of water is held upside down, but water will not pour out. Now matches, pencils, etc., are inserted up thru the neck of the bottle, yet water will still not flow. At your command however. water will pour from the bottle and stop again, as you wish.