Lovene for Lysets Forplantelse. 95 



- 5, V (dy (X' + djxO + d^f^' + d,+0) ; 



(270) 5'= — ,a V' (« + dj <?) -,ß V («' + dt<P')) — 



- ,T V (dj, (X + dt x) + d^ (^ + dt +5) - 



- ,s v (dy (X' + dj X') + d^ (1" 4- d^ *-)) ; 



t'= — a„ V' (* 4- «'t <?) — ß" v («' + dt <P'^ — 



- V„ V (dy (X + djx) + dj. (^ + dt *)^ - 

 -8. V'(dy (î' + dt XO + d^ (^f + d^q,'))- 



•»z ^ - V "= (•'?-'^")V"[d^(X+d,x)-dy(^-f d^q,)] + • 



+ E, V" fd- (X' + dj x') - d (*' + dt .I,')] , 

 (280) '- y ^ 



•»jV- dyX = ,E V" [d^ (X + dt x) - dy (* + dt+)] 4- 



+ (dt-E) [d^ (X' + dtX') - dy (x' + dt xO] • 

 Heraf fiudes endvîdere: 



in 



^t/«' .. . , . ^1/ß' 



(df-E„).V''d^-Y,V'd^ 



d^ +d 





d*4-d 



E, V''d|- S Vd Î 

 _ E,V* + S,V' j j (*' + d,V); 



