1. The Engineer, 733, Dec. 31, 1937.
2. The Engineer, 509, June 7, 1940.
3. See, for example, Fuel, 7, No. 11, 505, Plate XX, Figs. 1, 2, 3, and 4.
4. See, for example, Fuel, 7, No. 9, 35, Fig. 1, Plate XV.
5. David, Leah and Pugh, Phil. Mag. (in the Press).