“Simple physics,” Leo grinned. “Cold water pressure is usually 3 or 4 bar. Your gravity-fed hot water tank is only 0.5 bar. The cold water just bulldozes the air bubble back where it came from.”
Old Man Higgins lived in a crooked cottage at the end of Puddledown Lane. One morning, he turned on his kitchen tap, and instead of a healthy rush of water, he got a pathetic sputter, a deep gurgle , and then nothing but a sad sigh of air.
Higgins shrugged.
A perfect, solid column of water poured out.