Abstract :
Discussion and author´s closures of paper 41–143 by W. W. Parker, presented at the AIEE Pacific Coast convention, Yellowstone National Park, August 27–29, 1941 and at the AIEE South West District meeting, St. Louis, Mo., October 8–10, 1941; published in AIEE TRANSACTIONS, 1941 (November section), pages 977–82.
