The ferro-plate is held between the thumb and first two fingers of
the left hand. The collodion bottle is held in the right hand, and
the collodion is poured on the right upper end of the plate, flowed
to the left upper corner, by deflecting the plate in that direction,
and then down the left side toward the hand, and the excess run back
into the bottle from the right lower corner, when it has all run
off, the plate should be gradually brought to a perpendicular
position and rocked from right to left, that is, perpendicular to
the end, [p018] then to the side, until the film has set or
become fixed, which may be ascertained by touching the film at the
lower corner of the plate, when, if it breaks and does not run
farther, it has set and should, without delay, be immersed in the
silver solution, where it should remain until it has become fully
sensitized, which will be in from 2 to 5 minutes.
The plate should be lowered into the bath by one continuous motion;
any stoppage will cause a line and spoil the plate.
The plate is sensitized when on removing it from the bath it
presents a smooth, yellowish surface; if it shows lines as of water
running off a greasy surface, it is not coated; return it to the
bath.