in the pipes inclined at an angle of 60 u00b0 to the horizontal and the resulting condensate flows by gravity back through the surge chamber to the boiler where it begins another cycle construction of the manifold is such that a 39 inch section of pipe is available at each position on the drawtwister and acts as a heater some heaters are equipped with removable wear plates which are grooved to provide a yarn track others heaters consist of only a grooved steam pipe which is lagged except for the front see fig3 and 4 to insure good yarn contact from top to bottom each heater surface exhibits a uniform convex curvature 3 8 34 u00b1 1 16 34 from straight at the mid point this curvature remains in the heaters at elevated temperatures e g 250 u00b0 c steam is supplied to the manifold by a high pressure steam boiler manufactured by electric boiler corporation ebcor the ebcor boiler fig2 and 5 consists of a pressure tank in which a cylinder open at the bottom is welded to the inside upper head of the tank thus dividing the tank into two concentric chambers a steam generating chamber a and a regulating chamber b three solid alloy electrodes c are suspended equidistant apart in the chamber each forming an apex of a triangle chambers a amp b are connected by a steam header d in which there is a pressure control valve which is normally open e of fig5 and pvc of fig2 when not operating the water seeks a common level in each chamber covering the top of the electrodes a small amount of potassium chloride and five.