TROUBLES IN OPAQUE PROJECTION 



[CH. VII 



FIG. in. DIAGRAM OF MODEL 8 DELIKEASCOPE SHOWING THE POSITION 

 OF THE RADIANT AND THE COURSE OF THE LIGHT RAYS FOR OPAQUE 

 PROJECTION WITH THE OBJECT IN A HORIZONTAL POSITION. 

 (Cut loaned by the Spencer Lens Co.). 



T Table for opaque objects. 



W Wheel by which the table is raised and lowered. 



D Diaphragm above the table for flattening out the page of a book. 



B Incandescent bulb which always gives light for the interior of the 

 machine. 



C Condensing lenses in front of the arc. 



O Large objective for opaque projection. 



() 1 Smaller objective for vertical projection. 



,]/ Mirror for throwing light downward for the lantern-slide compartment 

 or upward through the vertical attachment. 



-If, Mirror for reflecting a perpendicular beam of light out through the 

 lantern-slide compartment; shown thrown up against the water-cell in this 

 figure (see fig. 177) 



M 3 Mirror used in connection with projection of the vertical side of an 

 object. 



M^ Mirror which assumes a position at 45 when the microscope is used 

 perpendicularly. 



P Prism which is thrown into the prism box when the microscope is used 

 in a perpendicular position. 



S Shelf upon which the lantern slide is placed previous to throwing it up 

 into the optical axis by the handle. 



// Handle of the lever for raising the slide into position. 



