THE 

 LONDON, EDINBURGH, and DUBLIN 



PHILOSOPHICAL MAGAZINE 



AND 



JOURNAL OF SCIENCE. 



[FOURTH SERIES.] 



AUGUST 1863 



XII. On the Theory of Light. By L. Lorenz*. 



IF we consider all the hypotheses belonging to our present 

 theory of light, that is to say, all those that are regarded as 

 necessary for the explanation of the double refraction, chromatic 

 dispersion, and polarization of light, it is difficult to guard our- 

 selves from all doubt of so complex a theoretical apparatus, 

 seeing that the probability of its truth must rapidly diminish as 

 the number of hypotheses involved in it increases, notwithstand- 

 ing that we may be convinced of the probability of each hypo- 

 thesis taken by itself. 



I have therefore tried to develope the theory of light with the 

 smallest possible number of hypothetical assumptions, whether 

 in regard to the nature of light itself, to that of the luminiferous 

 medium, or to that of material bodies ; and it will appear, as the 

 result of the present investigation, that an essential part of the 

 ordinaiyphysical hypotheses are not needed for the explanation of 

 the phenomena of light, inasmuch as the theory is capable of 

 being carried through in a manner different from that which has 

 been hitherto followed in the investigation of this subject, and 

 consisting in the further development of the formal side of the 

 theory. 



I. The Differential Equations of the Motion of Light in Hete- 

 rogeneous, non-absorhent Media. 



When the laws of the motion of light in homogeneous isotropic 

 media, and those of its passage from one such medium to another 

 of the same kind, are known, it is evidently possible to generalize 



* Poggendorff's Annalen der Physik und Chemie, vol. cxviii. p. Ill 

 (February 1863). 



Phil Mag. S. 4. Vol. 26. No. 173. Aug. 1863. G 



