58 



PRACTICAL PHOTOMICROGRAPHY. 



The following apparatus will be required beyond the things 

 already mentioned : 



FIG. 19. DRY-RACK. 



FIG. 20. WASH-TROUGH. 



For all kinds of contact printing: Printing frames (see 

 later). 



For enlarging and reducing which may be postponed till 

 some practice has been gained in other works : A suitable cam- 

 era, or arrangement of other cameras (see later) ; also a suitable 

 photographic lens. 



FIG. 22. PNEUMATIC HOLDER. 



A squeegee. Some glass plates or ebonite sheets a good 

 deal larger than the largest negatives to be made direct. 



