Abstract: A cooling slot for passing cooling fluid through a heated plate such as an airfoil blade for use in gas turbine engines is created by forming a first plurality of passages within the blade, and then forming a second plurality of passages within the blade, wherein preselected of the passages of the second plurality intersect at least one of the passages of the first plurality to define a number of nodes between the points of intersection. When cooling fluid is passed through the blade, the nodes act as turbulence promoters and area increasers for improving convective heat transfer between the blade and the cooling fluid.This is a divisional application of application Ser. No. 219,005 now U.S. Pat. No. 3,819,295 issued June 25, 1974 filed Sept. 21, 1972 and assigned to the assignee of the present invention.