Abstract: A method and apparatus for severing a length of insulating batting and simultaneously cutting only the insulating material thereof is provided. The insulating material between the severed edge of the insulation batting and the cutting line through the insulating material can be removed to expose a length of backing which can be secured to the uncut portion of the insulation batting length when the insulation batting length is wrapped around a length of a heating and cooling duct or the like. The apparatus includes a pair of rotating cutting wheels rotatably mounted on a carriage movable along an elongate carriage rail. A pinion gear mounted to each rotating cutting wheel for rotation therewith meshes with a rack secured to the elongate carriage rail to cause rotation of the rotating cutting wheel in response to movement of the carriage along the carriage rail.

Abstract: .beta."-Al.sub.2 O.sub.3 is a highly desirable material for serving the double function of solid electrolyte and separator in a rechargeable battery that employs sodium, Na, as the anode and sulfur, S, as the cathode. But conventional means for manufacturing the .beta."-Al.sub.2 O.sub.3 require temperatures between 1400.degree. and 1600.degree. C. By reacting .theta.-Al.sub.2 O.sub.3 with Na.sub.2 O, or a compound that yields Na.sub.2 O on decomposition, the desired .beta."-Al.sub.2 O.sub.3 is obtained at temperatures as low as 950.degree. C.