BOTANICAL PHOTOGRAPHY 189 



4. Do not keep plates, films, or papers in the same room with the chemicals. 



5. Keep everything clean. Dust may be removed from a plate by tapping 

 it gently on the table. If a brush is used at all, keep it clean, for it is as 

 likely to distribute dust as to remove it. 



6. If hypo is spilled or even rocks over a little, wipe it up, preferably with a 

 rag wet with potassium permanganate. If allowed to dry, the hypo dust 

 may cause spots on negatives and prints. 



7. A temperature of 65°-70° F. is about right for most photographic work. 



8. Developers keep longer if made up in two solutions, with the developing 

 agents in one and the carbonate of soda in the other. 



9. Be skeptical about "safe lights," even when dealing with lantern slides, 

 slow plates, or even with papers. 



10. Most spots are due to dirt, in the dark room, in the camera, on the lens, or 

 on the emulsion. 



REFERENCES 



Some of the references are advertising pamphlets, but since they are intend- 

 ed to bring the best results with their products, such directions are worth 

 studying. 



Cramer, Manual on negative-making and formulas. St. Louis, Mo., or 30 E. 

 Randolph St., Chicago, 111. : Cramer Dry Plate Co. (Furnished free.) 



Fraprie, Frank R., American photography exposure tables and manual. 

 Boston, Mass.: American Photographic Publishing Co. (About Sl.OO.) 



Mallinckrodt Chemical Works, The chemistry of photography. St. Louis, 

 Mo. : Mallinckrodt Chemical Works. (50 cents.) 



Eastman Kodak Company, Lantern slides; how to make and color them. 

 Color plates and filters. 



Walmsley, W. H., The A.B.C. of photomicrography. New York City, N.Y.: 

 Tennant & Ward. 



Duncan, F. Martin, First steps in photomicrography, a handbook for 

 novices. London, E.C. 4., England: Iliffe & Sons, Ltd., 20 Tudor St. 



Glover, B. T. J., Print perfection, how to attain it. London, E.G., 4., Eng- 

 land: British Periodicals, Ltd. 19, Cursitor St. (About 50 cents.) 



Wall, E. J., Photographic facts and formulas. Boston, Mass.: American 

 Photography Publishing Co. 



., Practical color photography. Boston, Mass.: American Photog- 

 raphy Publishing Co. 



Hampton, M. Monroe, Photo coloring and tinting. Chicago, 111.: Central 

 Camera Co., 230 S. Wabash Ave. ($L00.) 



Bailey, R. Child, Photographic enlarging. Dorset House, Tudor St., Lon- 

 don, E.C. 4, England: Iliffe & Sons. 



