1. C. Eckart,Hydrodynamics of Oceana and Atmospheres(Pergamon Press, New York, 1960), p. 59.
2. The present Eq. (7) is essentially the same as Eq. (4) of Sec. 72 of reference 2. Since the earth’s rotation is here neglected, Ω = 0; terms in V2∕c2 have also been omitted in Eq. (7). The quantityQthat is used in reference 2 is proportional to h:h = −Q∕(ρc)12. Derivatives of ρc are here neglected; this is justifiable in the ocean, but not in the atmosphere.
3. E. U. Condon and P. M. Morse,Quantum Mechanics(McGraw-Hill Book Company, Inc., New York, 1929), Chap. II.
4. Reference 4, pp. 47–52.