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1879 Encycl. Brit. X. 50/1 Such needles have great advantages—where, for instance, the time of oscillation, the logarithmic decrement, or the extent of swing of the needle has to be observed.

1908 E. H. Barton Text Bk. Sound x. 577 Hartmann-Kempf found that the relation between logarithmic decrement and amplitude for three makes of tuning-fork is almost linear.

1913 Year-bk. Wireless Telegr. & Teleph. 294 The Marconi Company has brought out an instrument called a decremeter, which enables an approximate measurement of the decrement of a circuit to be made.

1927 E. G. Richardson Sound iv. 121 To estimate the rate of decay, the ratio of the amplitudes in two successive periods is obtained, a quantity which is known as the decrement. It is the logarithm of this quantity..which usually figures in calculations.

1929 J. A. Ratcliffe Physical Princ. Wireless i. 14 The reciprocal of this quantity, r√ ^c/ _l, is of great importance in the theory of oscillatory circuits; it is known as the decrement of the circuit, and corresponds to the logarithmic decrement of a mechanical oscillatory system.

1936 L. S. Palmer Wireless Engin. iii. 47 Circuits with small decrements have good selectivity.

1966 W. T. Thomson Vibration Theory ii. 48 A body vibrating in a viscous medium has a period of 0·20 sec. and an initial amplitude of 1·0 in. Determine the logarithmic decrement if the amplitude after 10 cycles is 0·02 in.