1 76 PROJECTION OF IMAGES OF OPAQUE OBJECTS [Cn. VII 



M 



ZEISS EPIDIASCOPE FOR OPAQUE AND FOR TRANSPARENT OBJECTS 

 IN A HORIZONTAL POSITION. 



(Zeiss' Special Catalogue). 



As shown in this figure the apparatus is set up for opaque objects. For 

 transparent objects M 2 (mirror 2) is removed when the light striking M 3 is 

 reflected to M 4 and thence up through the object to M 1 and to the screen. 



Commencing at the right : R Parabolic reflector, which projects the light 

 from the crater through (W) the water-cell to M 1 the mirror which is at the 

 proper angle for reflecting the light down upon the opaque object. From the 

 opaque object the light is irregularly reflected through the objective to M 1 . 

 M 1 serves to reflect the rays from the objective to the screen. 



V Ventilator. M 3 and M 4 are mirrors for use in reflecting the light through 

 horizontal transparent objects. 



