STEADILY ALTERNATING CURRENT ON A LONG LINE. 331 



Tiected with electric circuits. These may be divided into subclasses 

 in a variety of v^ays. The transients particularly discussed in this 

 paper are the regular transients M, v^hich are a branch of the in- 

 itiating a.-c. wave transients, and which belong to the principal class 

 A through subdivisions E, F, H, and /. 



Artificial Line Employed. — The measurements reported in this 

 paper were all carried out on an artificial line in the electric trans- 

 mission laboratory of the Massachusetts Institute of Technology. 

 This is an artificial power-transmission line of 26 7r-sections, de- 

 signed by Drs. Pender and Huxley, the construction and dimensions 

 of which have been described elsewhere.^ It represents an aerial 

 singlephase copper conductor of 253 sq. mm. (500,000 cir. mils) 

 cross section, using ground or neutral return, and having the con- 

 stants given in the following table. 



TABLE II. 

 Particulars of the Artificial Line Chiefly Used in Tests. 



Length of Conjugate Smooth Line per section 48.28 km. 30 miles 



Total of 26 sections 1255 km. 780 miles 



Whole Line. Per Section. 



Conductor Res : R at 19° C, ohms 87.71 3-374 



Inductance L, henrys 1-457 0.05605 



Reactance X, at 60.6^ — ', ohms 555 21.345 



Dielectric Leakance G, mhos i5-i4 X 10-^ 0.5823 X lO"^ 



Dielectric Capacitance C, farads 12.58 X icr^ 0.4838 X lO-^ 



Dielectric Susceptance B, at 60.6 ~^, mhos 4-790 X lo-s 0.1842 X lo-^ 



Linear Constants. Per Wire Km. Per Wire Mile. 



Linear Resistance r at 19° C, ohms 0.06987 0.11245 



Linear Inductance /, henrys 1.1611 X lO-^ 1.8683 X IQ-^ 



Linear Reactance x, at 60.6 '~', ohms 0.4421 0.71 15 



Linear Leakance ^r, mhos 1.206 X lO-^ 1.941 X io~^ 



Linear Capacitance c, farads 1.002 X lo-^ 1.6127 X lo-^ 



Linear Susceptance b, at 60.6'—', mhos 3.816 X lo-^ 6.141 X 10-^ 



Surge Impedance z^ of line, or of a section, at 60.6^ 342.5^4° 24' ohms Z 

 Angle subtended by whole line, at 60.6 '~', 



1.6405/85° 25'8" = 0.1315 +/ 1.6352 = 0.1315 + j 1. 041 h3rps Z. 

 Angle & subtended by single section, at 60.6 — •, 



5 Bibliography 170 and 30. 



