3942.  ----- [WILLIAMS, R] (Du Pont Ammonia Corp.).Apparatus for Synthetic Reactions Such As Ammonia Synthesis. United States Patent 1,809,291, June 9, 1931. Chem. Abs., vol. 25, 1931, p. 4153.

U-shaped tube extends into a receptacle for the main body of catalyst, and heat exchange is permitted between the entering gaseous mixture and the main body, the tube enclosing another portion of catalyst in the path of the gaseous mixture.