418 PROCEEDINGS OF THE AMERICAN ACADEMY. 



periodic, are intimately connected with a certain angle, cos~^ (p/c) or 

 coslr'^ (p/z), connected with the circuit constants. 



The polar-coordinate type of vector- diagram is not so conveniently 

 adapted to the o. c. circuit as the crank-projection diagram. 



The aperiodic case may be treated as the limiting case either of the 

 oscillatory, or of the ultraperiodic, circuit. 



List of Symbols Employed. 



A. B. Constants of integration (coulombs), 



a. c. abbreviation for alternating current. 



c, Ci, C2, Cz Permittance of a condenser, or of each of several condensers 



(farads). 

 y Oscillation conductance of an 0. c. circuit (mhos). 



5i, S„, ^2^ Logarithmic decrement of an oscillating quantity ( loge — ^ J 



during the angular interval of 1 radian, -n- radians (semi- 

 period), and 2 tt radians (complete period), of the radius 

 vector (numeric). 



e ■ =2.71828. . . . 



Bq Initial vector amplitude of emf. of self-induction (volts Z ). 



jt'(j Initial emf. of self-induction in circuit (volts). 



A" Charging emf. impressed upon a condenser (volts). 



e, e Instantaneous value of emf. of self-induction in an 0. c. 



circuit, and the undamped value of same (volts). 



e^, Bf Undamped and damped instantaneous values of self- 



induction emf. in phase with the current (volts). 



/g Initial current strength in a circuit (amperes). 



y^ Initial vector amplitude oscillating current (amperes Z ). 



/ =/o/ V^j the r. m. s. value of initial vector current amplitude 



(amperes). 



/, i Undamped and damped instantaneous currents (amperes). 



/ = V— 1, quadrantal operator. 



f, A, k, h, Inductance of an 0. c circuit, and of particular parts 



thereof (henry s). 

 7)1 any positive integer (numeric). 



n Frequency of oscillation of a circuit (cycles per second). 



o. c. abbreviation for oscillating-current. 



TT =3.14159 . . . (numeric) 



P/t. Q. Any oscillatory physical quantity pertaining to an 0. c. 



circuit. 



