Abstract: A coolant arrangement is disclosed for magnetic coil turn assemblies in which cooling fluid is flowed through a supply header along the face of a coil turn and into coolant inlet openings positioned along the face of the coil turn beneath the supply header structure. Coolant is directed through coolant channels around the magnetic coil turn, and into outlet openings. The outlet openings are in fluid communication with a return header also positioned on a flat face of a magnetic coil turn. There is also disclosed a method and apparatus for passing coolant through adjacent coolant channels in a magnetic coil turn in opposite directions. The cooling means disclosed avoids creating hot spots in the vicinity of the coolant inlets and outlets and reduces stresses in the coil in the vicinity of the coolant inlets and outlets. It also provides for maintaining a uniform average temperature throughout the coil turn.