A ceramic heater is provided that has a heat generating resistor and a lead member which supplies electric power to the heat generating resistor buried in a ceramic body, and exhibits excellent durability by controlling the cross sectional shape and plan configuration of the heat generating resistor. In one embodiment, a marine vehicle may obtain magnetic measurements in a location around a drilling site. Alternatively, the tool may have one or more magnets installed in the base, i. The players may carry over the symbols andor symbol combinations they have collected across multiple gaming sessions and multiple gaming terminals. Local increased coolant velocity is provided by any means, including decreasing the area-in-flow of the coolant plenums wherein increased velocity is desired, shaping or baffling either or both inlet or outlet coolant tanks in fluidic contact with coolant plenums wherein increased velocity is desired, or a combination thereof.