These experiments were carried out on full-grown and on young subjects.
As in previous experiments, doses of different sizes were employed. A
dose of 0.2 gram per kilo was tried first and then reduced gradually to
0.1 gram per kilo.
_Cat 10. Female. Weight, 2,970 grams._
October 9, 1909: 1.30 p. m., 30 cc 2 per cent caffein (0.2 gram per
kilo) injected into the peritoneal cavity; urine examined for albumin
and sugar, negative; cat found dead at 2.30 p. m. No urine in the
bladder.
_Cat 16. Black female. Weight, 2,420 grams._
October 9, 1910: Urine examined for albumin and sugar, negative; 2.30
p. m., 22 cc 2 per cent caffein (0.183 gram per kilo) injected into the
peritoneal cavity; found dead at 3 p. m.
_Cat 99. Well-fed gray female. Weight, 3 kilos._
June 22, 1911: 3.40 p. m., 15 cc 2 per cent caffein injected into
peritoneal cavity; salivation and marked irritability within one hour
after injection.
June 24: Alive, appetite good.
_Cat 98. Well-fed black male. Weight, 4,100 grams._
June 22: 3.45 p. m., 20.5 cc 2 per cent caffein (0.1 gram per kilo)
injected into peritoneal cavity; very irritable a few minutes after
injection, no other symptoms.
June 24: No symptoms, appetite good.
_Cat 93. Black and white. Weight, 1,450 grams._
June 22: 3 p. m., 30 cc 2 per cent caffein (0.137 gram per kilo)
injected into peritoneal cavity; salivation, no other symptoms; under
observation until 6 p. m.
June 23: 9 a. m., no urine, cat showed no symptoms.
June 24: 9 a. m., no symptoms, took nourishment as usual.
_Cat 87. Well-fed white female. Weight, 2,615 grams._
June 23: 2.45 p. m., 19 cc 2 per cent caffein (0.145 gram per kilo)
injected into peritoneal cavity; became irritable and restless.
June 24: 9 a. m., no symptoms, took nourishment as usual.
_Cat 97. Gray. Age, 3 months. Weight, 500 grams. Diet, meat._
June 24: 2.25 p. m., 5 cc 2 per cent caffein (0.2 gram per kilo)
injected into peritoneal cavity; 4 p. m., no symptoms.
June 29: Died.
_Cat 96. Gray and white. Age, 3 months. Weight, 575 grams. Diet, meat._
June 24: 2.20 p. m., 4 cc 2 per cent caffein (0.139 gram per kilo)
injected into peritoneal cavity; 3.55 p. m., no symptoms.
June 30: Died.
_Cat 95. Black. Age, about 3 months. Weight, 860 grams. Diet, meat._
June 24: 10.15 a. m., 8.6 cc 2 per cent caffein injected into
peritoneal cavity, salivation immediately after injection; 10.25,
convulsions and paralysis; died 10.45 a. m. _Autopsy_: Macroscopical
examination of the organs, negative.
_Cat 94. Black and white. Weight, 790 grams. Age, about 3 months.
Diet, meat._
June 24: 10 a. m., 8 cc 2 per cent caffein injected into peritoneal
cavity; 4 p. m. under continual observation since injection, cat very
irritable, respiration more rapid than normal, diarrhea present.
Examination of the above protocols show that a dose of 2 decigrams per
kilo was fatal within one hour to one cat and that a somewhat smaller
dose killed another individual in 30 minutes. Amounts under 0.15
gram per kilo were just sufficient to induce mild symptoms, such as
increased irritability and salivation, which disappeared within a few
hours. In no case were the effects noticeable on the following day.
The experiments on young kittens are especially interesting, as they
proved, contrary to expectation, to be distinctly more resistant than
full grown individuals. The death of Nos. 97 and 96 within five and six
days, respectively, can not be ascribed to caffein, since some of the
controls also died. Moreover, it will be remarked in this connection
that no symptoms appeared in three of the four young kittens after the
administration of a dose which was rapidly fatal to adult cats. The
rapid death of No. 95 after the same dose forms an exception which can
not be accounted for, as macroscopical examination at autopsy proved
negative.