Greetings, I have read several threads concerning the operation of "inverted bottle dispensers", however, I have not found in any of them, the answer to my question: How can I vary or control the amount of air vs water that will exchange places at one given time, from a system at rest? As to clarify, please imagine a Splarkletts or similar dispenser - the simplest kind, comprised of a small bowl with a faucet and an inverted bottle above it, held by the frame of the apparatus. My experiment does not apply to any water being dispensed by the faucet; I am only concerned with the fact that, at some point, water evaporates enough so that air is let in. As a bubble travels upwards, that same volume of water is going to be let out. This dispensing of water, in turn, will eventually close the passage of air again as the water line rises and seals the mouth of the inverted bottle. I am interested in factors that will aid in varying the amount of air in the bubble that forms upon natural evaporation of the water in the bowl. In other words, I am interested in building a system that will make the dispensed water raise the water level as much as possible, from a balanced state, causing the "evaporation spurs" to be the farthest apart, but when they occur, they will cause the greatest variation of height on the water line; which is ultimately what I am interested in -" the height of the variation of the water line in the bowl", under the conditions described. Perhaps, some of these factors could include the height of the water column in the bottle; the girth of the bottle and/or girth of bottle neck (up to no neck at all); the shape and thickness of the bottle mouth, as to facilitate of not the need to win over superficial tension of water in bow; angle of walls of bottle; size/diameter of bowl; etc. Thanks for considering my question.