Napierian Logarithms : Natural logarithms. Logarithms with base e (=2. 718. . . Thus 5 = e1. 61. They are used in calculations about exponential and hyperbolic functions
H. J. Porter (Chairman - Technical Committee), Dictionary of Fire Technology, The Institution of Fire Engineers, The Victory Press (Leicester) Ltd. 1979 UK. (Fr Tech - Brit) {81}