May 20: 0.75 gram caffein was fed at 12.45 p. m. The dog vomited during the night and tremors were observed the next morning. The urine collected was examined for albumin and sugar, but neither was found. May 21: 12 noon, 0.75 gram caffein was fed. The dog weighed 6 kilos, which therefore represented a loss of 0.4 kilo. Grew abnormally thirsty and lost appetite, but no other symptoms of caffein poisoning were observed. May 22: The dog was again given 0.75 gram caffein at 12 noon. The examination of the urine for albumin and sugar gave negative results. The dog died at 4.15 p. m. The fatal dose for this dog was therefore 0.125 gram caffein per kilo, and the total amount of caffein ingested in six days amounted to 3.25 grams, or 0.54 gram per day, which makes 90 mg per kilo. _Dog 21._ _White female bull._ This dog was kept on a diet exclusively of meat, and was given water ab libitum. From 0.5 to 0.6 gram of caffein was administered daily for seven days; the doses were then increased and were given at longer intervals. No symptoms of the effects of caffein were observed until a dose of 1.5 gram was fed, when diarrhea was noticed on the next day. In the following record the details of the experiment are given: ----------+---------+---------- Date. | Weight. | Caffein. ----------+---------+---------- | _Kilos._| _Grams._ June 7 | 12.5 | 0.5 June 8 | 12.5 | .5 June 9 | 12.5 | .5 June 10 | 12.3 | .6 June 11 | 12.3 | .6 June 12 | 12.3 | .6 June 13 | 12.3 | .6 June 14 | 12.3 | .8 June 16 | 12.7 | 0.8 June 18 | 12.9 | 1.0 June 21 | 13.4 | 1.2 June 24 | 13.3 | 1.5 June 25 | (1) | .0 June 27 | 13.5 | 1.5 June 30 | 13.5 | 1.75 ----------+---------+---------- (1) Diarrhea. July 2: 11.30 a. m., 2.0 gram caffein fed by mouth; 1.30 p. m., tetanus, dog died. The total amount of caffein fed to dog No. 21 out of the 25 days of the experiment was 14.45 grams, or an average of 578 mg per day, which amounts to about 42 to 43 mg per kilo of body weight.