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Proceedings of the Royal Society 
experiment where the same dose of extract of physostigma was 
given along with only four grains of sulphate of atropia, and they 
appeared to he caused by the latter substance chiefly. 
Experiment 4. — Four days afterwards, it was found that 0*5 grain 
of extract of physostigma was a fatal dose for this rabbit also. 
Evidence of a still more satisfactory character in support of the 
result that the toxic action of physostigma may be prevented by 
atropia was obtained with dogs. 
Experiment 5 . — Eight grains of sulphate of atropia and three 
grains of extract of physostigma, in distilled water, were injected 
under the skin of a vigorous English terrier dog, weighing ten 
pounds. The chief symptoms were dilatation of the pupils, partial 
paralysis, and hypnotism. Of these, the first continued for several 
days, and the last for less than twenty-four hours. The partial 
paralysis continued for only forty minutes, after which the dog was 
in a perfectly normal condition, except that the pupils were in full 
dilatation, and that a tendency to indulge in sleep was manifested. 
Experiment 6. — Three weeks afterwards, the same dog received 
eight grains of sulphate of atropia and six grains of extract of 
physostigma — the latter being twice as large a dose as that given in 
the previous experiment. Dilatation of the pupils and considerable 
loss of motor power were again produced ; but, in addition, certain 
symptoms were prominently exhibited that were undoubtedly due 
to the physostigma, such as tremors and exaggerated bronchial 
secretion. The partial paralysis and tremors continued for more 
than three hours, and the dilatation of the pupils for several days, 
after which the dog perfectly regained its former condition. 
Experiment 7. — In order to show distinctly that the atropia had 
prevented the fatal action of the physostigma given in these two 
experiments, this dog received, some weeks afterwards, three grains 
of extract of physostigma — a dose equal to that from which it 
recovered in the first experiment, and only half as large as that from 
which it recovered in the second. The results w r ere that partial 
paralysis and tremors were quickly produced, that the lachrymal 
and salivary secretions were profusely increased, and that the 
respirations became more and more laboured and jerking, until 
they ceased in death, at seventeen minutes after the administration. 
These experiments appear to prove that in rabbits and dogs the 
