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Multiple Images in Mirrors 

 By Wai. Balfour Stokes. 



(Bead December 18th, 1896.) 



The origin of multiple images in plate-glass mirrors, and 

 their behaviour, seem to have attracted but little notice among 

 microscopists. They have been noted, and a partial remedy has 

 been prescribed, but their origin seems to have been either too 

 simple or too complex for explanation.* 



When attention has been called to these images, simple, and 

 I believe efficient reasons have been given ; but their authors 

 did not explain the behaviour of the images when the mirror is 

 revolved. 



A figure will best show my own idea as to their origin. In 

 Fig. 1, A is the glass surface, B the silver surface, O the 

 object, and E the eye. 



In the direction 1, 2, 3, appear the first three images. No. 

 1 is from the glass surface, No. 2 is from the silver surface, and 

 No. 3 is from the silver and air surfaces. 



Move a card along A towards 1, and No. 3 disappears first, 

 No. 2 immediately after, and No. 1 when the card reaches that 

 point. 



So much for their origin. 



It will be asked, perhaps, how the images can alter their 



* Dallinger's " Carpenter," 1891, p. 171. . 



