danger of asphyxia, tracheotomy may have to be performed.

=Carbonate of Sodium= occurs as _soda_ and _best soda_, the former in
dirty crystalline masses, the latter of a purer white colour. It is also
found as 'washing soda.'

_Symptoms, Post-Mortem Appearances, Treatment, and Extraction from the
Stomach._--As for potash.

_Tests._--Alkaline reaction, effervesces and evolves carbonic acid when
treated with an acid; crystallizes, gives yellow tinge to blowpipe
flame. No precipitate with tartaric acid, nor with bichloride of
platinum.

=Ammonia= may be taken as _liquor ammoniae_ (harts-horn), as carbonate of
ammonium, as 'Cleansel,' or as 'Scrubb's Cloudy Ammonia.'

_Symptoms._--Being volatile, it attacks the air-passages, nose, eyes and
lungs, being immediately affected; profuse salivation; lips and tongue
swollen, red, and glazed. The urgent symptoms are those of suffocation.

Inhalation of the fumes of strong ammonia may lead to death from
capillary bronchitis or broncho-pneumonia. Death may result from
inflammation of the larynx and lungs. When swallowed in solution, the
symptoms are similar to those of soda and potash.

_Post-Mortem Appearances._--Similar to other corrosives.

_Method of Extraction from the Stomach._--The contents of the stomach,
etc., must be first distilled, the gas being conveyed into water free
from ammonia.

_Tests._--Nessler's reagent is the most delicate, a reddish-brown colour
or precipitate being produced, but ammonia may be recognized by its
pungent odour, dense fumes given off with hydrochloric acid, and strong
alkaline reaction.

_Treatment._--Vinegar and water. Other treatment according to symptoms.

_Fatal Dose._--One drachm of strong solution.

_Fatal Period (Shortest)._--Four minutes.

XVI.--INORGANIC IRRITANTS

=Nitrate of Potassium (Nitre, Saltpetre)--Bitartrate of Potassium (Cream
of Tartar)--Alum (Double Sulphate of Alumina and Potassium)--Chlorides
of Lime, Sodium, and Potassium.=--All these are irritant drugs, and give
the usual symptoms.

XVII.--CHLORATE OF POTASSIUM, ETC.

=Chlorate of Potassium= produces irritation of stomach and bowels;
haematuria; melaena; cyanosis, weakness, delirium, and coma.

_Post-Mortem._--Blood is chocolate-brown in colour, and so are all the
internal organs; gastro-enteritis; nephritis.

_Tests._--Spectroscope shows blood contains methaemoglobin; the drug
discharges the colour of indigo in acid solution with SO