He read for his PhD in 1961 with a thesis on Variable Hydromagnetic Motions. Models with closed gate B are called hydromagnetic dynamos. The technology on HydroMagnetic Rockets utilizes linear induction motors (LIMs) to propel boats uphill. Such dynamos are sometimes also referred to as "hydromagnetic dynamos". When the HydroMagnetic water coaster opened, it operated with ten 6-passenger boats. When the HydroMagnetic water coaster opened, it operated with fourteen 4-passenger boats. Virtually all dynamos in astrophysics and geophysics are hydromagnetic dynamos. RiverRush uses ProSlide Technology's hydromagnetic technology to propel the rafts up hills. Dessler, A. J. and E. N. Parker, Hydromagnetic theory of geomagnetic storms.