BOTANICAL PHOTOGRAPHY 



165 



holding it as level as possible ; pour the balsam over it, letting the bal- 

 sam flow evenly over the whole surface ; then tilt the slide and pour the 

 balsam back into the bottle. Put the slide in the rack to dry. 



Mounting. — Add a suitable mat and a clean lantern-slide cover. Re- 

 member that the effect of a first-class lantern slide may be impaired or 

 even ruined by an inartistic mat. Bind the slide and cover together 

 with a lantern-slide binding strip. Paste on the label, or, if you prefer, 

 paste the label on the mat before binding, so as to have it protected by 

 the cover. Lay the slide down so that the positions are just as they 

 were in the original, and then paste the "thumb mark" in the lower 

 left-hand corner. 



The Gevaert lantern slide plates are used by many botanists. They 

 are good for general work and the formulas for sepias, purples, and 

 reds by direct development make them attractive for lantern slides of 

 scenery. 



Developers. — 



For Lantern Slides from Strong Negatives 



Distilled water 1,000 c.c. 



Metol 



Hydrochinon 



Sodium sulphite (crystal) . 

 Sodium carbonate (crys- 

 tal) 



Potassium bromide 



3g. 



Ig- 

 40 g. 



50 g. 

 Ig. 



For Lantern Slides from Weak Negatives 



Distilled water 1,000 c.c. 



Metol 1§ g. 



Hydrochinon 6 g. 



Sodium sulphite (crystal) 50 g. 

 Sodium carbonate (crys- 

 tal) 100 



Potassium bromide 1 



g- 

 g- 



The time of development will be about 2-2| minutes for black tones, 

 and 1-li minutes for warm tones. 



For sepia, purple and red tones. — Use the Gevaert warm tone lan- 

 tern-slide plates and expose as for ordinary tones. Use the following 

 developer. 



A B 



Distilled water 1,000 c.c. Distilled water 250 c.c. 



Metol H g- Ammonium carbonate 30 g. 



Hydrochinon 6 g. Ammonium bromide 30 g. 



Sodium sulphite (crystal) . 50 g. 

 Sodium carbonate (crys- 

 tal) 100 g. 



Potassium bromide 1 g. 



