SCIOPTICON MANUAL. 



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darkness, but it is quite as agreeable when done without 

 special haste. 



When American slides, 4 } inches long, are used, the out- 

 going slide is stopped by the catch n, Fig. 44, at the end 



Fig. 44. 



of the groove, just when the one driving it is exactly in the 

 field of the lenses. It is then lifted out to make room for 

 the next move. French slides, 4 inches long, are stopped 

 by the end m of the turn-buckle pivoted at JV, which is 

 turned up above the bottom of the groove for that purpose. 

 For English, or square slides, 3 inches long, the end m l is 

 raised. If the slides are irregular or mixed, the turn-buckle 

 may be kept level, out of the way, gauging the slides by 

 the finger at the condenser. By these appliances the appa- 

 ratus can be worked with ease and precision in the dark. 



The automatic cut-off is not suited to wooden-mounted 

 slides; they can rest on two screws projecting from the 

 front side of the slide-frame by starting the draw-front just 

 a little forward. If the assortment consists mostly of wooden- 

 mounted slides, however, it is better to remove the latch- 

 frame (starting at the spring e), and insert the ordinary 

 Sciopticon stage. The front opaque curtain may be used 

 as a cut-off, as shown page 35, or the slides may follow one 

 another in panorama style, smooth and steady, as usual. 

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