With a view to this, always scrape your buffs with a dull knife, or with one blade of your shears, the first thing in the morning, and after brushing them thoroughly, dry them, either in the sun, by a stove, or in the buff-dryer.

It is equally important that the polish and the brush should be kept dry.
Want of success may arise from vapors of iodine or bromine in the camera box, mercury bath, or even in the buffs.

It is incredible how small a quantity of these vapors will affect the effect of light when coming in contact with the plate, after or during the exposure in the camera.

It is therefore necessary to be cautious not to mix chemicals, nor open your boxes or bottles in your room, but take them out to do it.

Never hurry the operation through from lack of confidence in the result.