Add the ingredients
five and a half ounces of nitrate of potash in powder and add to it in a
convenient size bowl ten ounces, by weight, of common commercial sulphuric
"Stir the whole with a glass rod,
and introduce as much finely-carded cotton, about two drachms, as will
absorb the mixture and be at the same time thoroughly charged with it."
Put a cover on the vessel, and
allow the action to go on for five minutes. Then remove the cover,
and with a glass rod, poke and separate the fibres of the cotton"
"If the action be too intense,
which is known by the extreme heat of the surface of the vessel, moderate
it by applying a cloth soaked in cold water to its external surface."
"Then let the cotton be plunged
into cold water, and washed so thoroughly that not the slightest trace of
acid can be detected. It should then be dried at a very low
temperature, and put past in a bottle for use."