Pie RN © myer 2/7 
Tue Corp Bats Process.—To sensitise the paper it 
should be fastened by glass-headed push pins to a flat surface. 
with a sheet of blotting paper underneath. As it is important 
that the sensitising solution should not come into contact 
with the pins, it is advisable to provide the latter with guards, 
which can easily be prepared by cutting small squares of 
cardboard, turning up the edges, and passing the pins 
through the middle. As the paper expands and crinkles on 
application of the liquid, the pins may be removed, and the 
paper restretched and again pinned down. The sensitiser is: 
A. Potassium chloroplatinite sol. 3 ccm 50 min. 
Lead-iron sol. 4.5 ccm 75 min. 
Sodium chloroplatinate 7.5 drops 7.5 drops 
Water 3to8ccm 50 to 130 min. 
Or: 
B. Potassium chloroplatinite sol. 3 ccm 50 min. 
Lead-iron sol. 4.5 ccm 75 min. 
Oxalic-gelatine sol. 1 ccm 17 min. 
Sodium chloroplatinate 7.5 drops 7.5 drops 
Water 3to8ccm 50 to 130 min. 
Or: 
C. Potassium chloroplatinite sol. 3 ccm 50 min. 
Lead-iron sol. | 3 ccm 50 min. 
Sodium ferric oxalate sol. 2ccm 33 min. 
Sodium chloroplatinate 7.5 drops 7.5 drops 
Water 3to8eccm 50 to 130 min. 
The quantity of water in each formula is dependent on the 
surface of the paper; smooth surfaces require less, rough 
ones the greater quantity. Increase of the water to 2 to 14 
times that given above gives grey prints. The above quantity 
of sensitiser is sufficient for 3750 qcm (580 sq. in.) of paper. 
Increase of the sodium chloroplatinate gives increased con- 
trasts, or an equal volume of a 10 per cent solution of 
