130 
PRACTICAL PHOTO-MICROGRAPHY. 
achieving the very difficult task of getting good contrast 
out of weak objects. If one intensification with some 
reagents is not enough we may repeat the operation, 
taking care that the washing between the operations is 
effective. 
Note .—When negatives are to be used for repro¬ 
duction by one of the photo-mechanical processes, as 
for book or article illustration, they ought to be 
“ plucky,” i.e., they ought to have clear shadows and 
fairly dense high lights ; for the production of such 
negatives, when the objects are devoid of actual or 
actinic contrast, the procedure of slight reduction, 
followed by intensification, will yield the best results 
likely to be obtained. At the same time, when the 
“markings” or details of an object are extremely 
minute or fine, there is danger of their being, to a 
certain extent, blocked or “ smudged ” by intensifica¬ 
tion, especially if reduction is omitted. 
