CARBON TETRACHLORIDE AND TETRACHLORETHYLENE          295

tetrachlorethylene into the larnyx of a dog weighing about 15 pounds, by means of
a pipette. No ill effects followed other than a slight cough. Another dog was
injected intratracheally with 1 c.c. tetrachlorethylene, without fatal results, although
vomiting, retching and dyspnea followed, as might be the case if water were injected
into the trachea.

In order to determine whether foxes are likely to be affected when
tetrachlorethylene enters the respiratory organs (as might occur if a capsule were
accidentally broken in the mouth) Hanson² broke six 1 c.c. capsules in the mouth of
each of two foxes without any ill results following, other than a temporary irritation
of the mouth as evidenced by profuse salivation and by the rubbing of the mouth
with the paws. Hanson adds :

Under similar conditions the use of carbon tetrachloride would undoubtedly
have brought about collapse and possible death from inhalation-intoxication.

More recent observations by Hanson³ have shown that tetrachlorethylene does
occasionally cause inhalation-intoxication in foxes. Consequently, it should be
administered in soft gelatin capsules and the patient closely watched to see that the
capsule is successfully swallowed. In case a capsule is broken in the mouth and
signs of collapse develop, such as dilation of the pupils, trembling and general
'grogginess,' it is advisable to commence artificial respiration. One recommended
method is to grasp the animal by the hind legs and to whirl it around in order to
centrifuge the drug from the lungs; then lay the animal down on the ground and
perform artificial respiration.

Cases of choking and death have been occasionally reported in dogs following
the administration of tetrachlorethylene enclosed in capsules, but when such cases
are properly investigated it is usually found that death was due to a capsule being
pushed down the trachea, with resulting mechanical suffocation. Occasionally a
hog may die following the administration of drugs in capsules. This may be
attributed either to a capsule having been pushed into the trachea or having lodged
in the retropharyngeal recess or blind pouch, setting up irritation and swelling,
the capsule itself causing death by suffocation.

Lamson, Bobbins and Ward⁴ found it impossible to produce surgical relaxation
(anesthesia) in certain dogs with tetrachlorethylene when using an ordinary ether-
bottle attached to a tracheotomytube, even though the tetrachlorethylene was
heated. Anesthesia could, however, be induced by the cone method.

  THE EFFECTS OF TETRACHLORETHYLENE ON THE LIVER AND OTHER ORGANS.

In comparing the toxicity of tetrachlorethylene with that of carbon tetra-
chloride on dogs, experimental evidence has shown that the former has no appreci-