28 Prof. E. Taylor Jones on Electrical 



fact the result above obtained agrees in this respect with 

 the results obtained experimentally in the liquefaction of 

 gases under compression. 



Change of E. 



48. As E increases with v constant, the axial constituents 

 of the determinant D increase, while the anaxial constituents 

 which depend on v remain generally constant. The effect 

 of that is to increase D and all its coaxial minors. If therefore 

 E be great enough, no amount of compression will reduce D 

 to zero, and liquefaction cannot take place. 



II. Electrical Oscillations in Coupled Circuits. .5?/ E. Taylor 

 Jones, D.Sc, Professor of Physics in the University College 

 of North Wales, Bangor *. 



[Plate I.] 



IT is well known that in a system consisting of two circuits 

 containing capacity, self-inductance, and sufficiently 

 great mutual inductance, each circuit has two natural periods 

 of electrical oscillation. The problem of determining the 

 constants of the two oscillations has been considered by 

 Oberbeck |, M. Wien J, and Drude §. Drude showed that 

 in addition to having different periods the two oscillations 

 also have in general different damping coefficients, and 

 calculated their values; he further showed how to calculate 

 the potential at the terminals of the secondary circuit at any 

 time after the application of a given potential-difference to 

 those of the primary. 



The present paper deals mainly with the case in which 

 the oscillations are started by breaking a current in the 

 primary. The expression for the secondary potential is 

 deduced for this case by Drude's method, and compared with 

 measurements of photographs obtained by means of the 

 short-period electrometer (or " electrostatic oscillograph," as 

 it has been called) described by the author || . The instru- 

 ment shows that the course of the variation of the secondary 

 potential is much simpler when the oscillations are started 



* Communicated by the Author. 



t Oberbeck, Wied. Ann. lv. p. 623 (1895). 



% M. Wien, Wied. Ann. lxi. p. 151 U897). 



§ Drude, Ann. der Physik, xiii. p. 512 (1904). 



|| E. T. Jones, Phil. Mag. August, 1907. 



