“Whirlpools, tornadoes​ and​ dust​ devils​ all​ use​ the​ same​ physics.​ A downward force, followed​ by​ a​n​ obtuse​ angle, a​ side​ways​ movement and​ then​ a​ spinning vortex​ which​ tries to​ remain​ perpendicular to​ the​ ground​ or​ ocean/river​ bed.
It's​ amazing​ what​ you​ can​ think​ about​ when​ a​ child​ is​ playing​ with​ a​ small​ plastic​ cone​ and​ trying​ to​ make​ it​ spin.”