“…Three different three-parameter equations were subjected to an explora- tory study of the practicability of various fitting procedures for the parameters. These three equations were the Clausius equation, as studied also by Freze and Chevalier (1978) and by Martin (1979), the equation studied lately by Usdin and McAuliffe (1976) which had previously been investigated by Himpan (1952) and by Fuller (1976), and finally the equation to be discussed below. The results of these preliminary investigations led us to rejecting the first two equations in favor of the third.…”