Of the numerous methods of measuring the surface tension (σ) of molten metals, the commonest is the method of the maximum pressure in a gas bubble or drop, the theory of which was developed by Cantor in 1892 [1]. Of 223 investigations published on the measurement of surface tension of molten metals up to the commencement of 1961, the method of maximum gas bubble pressure was used in 98. The popularity of this method is due to its considerable advantages: relatively simple apparatus, the results are independent of contact angle, and for determining the surface tension of a me lt, it is necessary to know, as a rule, not more than four experimentally measured values, and so forth.