574 DR THOMAS R. FRASER ON THE ANTAGONISM BETWEEN 



fseces had been passed. In fifteen minutes, the rabbit was lying on the side, and 

 laboured and infrequent gasping respirations were occurring. Soon afterwards, 

 the sensibility of the conjunctiva disappeared, the cardiac impulses became 

 extremely weak, and it was only at long intervals that a feeble gasp occurred. 

 Death occurred at nineteen minutes after the administration of physostigma. 



It is shown by these two experiments that in rabbits atropia retains its 

 remarkable power of counteracting the lethal action of physostigma even when 

 its toxic activity in these animals is greatly increased. 



Experiment ivith a Preparation of Physostigma different from that used in 

 all the other Experiments. — As the preceding experiments were, without excep- 

 tion, made with extract of physostigma and sulphate of physostigmia prepared 

 by myself, it seemed not altogether superfluous to check the results that were 

 obtained, by making some additional experiments with a preparation for whose 

 activity and properties I was not responsible. Accordingly, several experiments 

 were made with an extract prepared by Dr Cook, of the well-known firm of 

 Messrs T. and H. Smith. With this extract essentially the same results were 

 obtained as with the preparations used in all the other experiments. It is, 

 therefore, unnecessary to give a description of more than one experiment in 

 which it was employed. 



Experiment 57-a. — A rabbit, weighing three pounds and eight ounces, 

 received, by subcutaneous injection, two grains of Dr Cook's extract of physo- 

 stigma, suspended in 40 minims of distilled water. One minute and a half 

 afterwards, it received, also by subcutaneous injection, half a grain of sulphate 

 of atropia, dissolved in 10 minims of distilled water. 



In three minutes after the injection of sulphate of atropia, the pupils measured 

 |£ths x J^ths of an inch, the measurement immediately before the experiment 

 having been ^jths x -^ths. In seven minutes, the pupils measured J-^-ths x ^-§ths 

 of an inch, the rate of the heart's contractions was considerably accelerated, 

 fibrillary twitches were occurring, and a little restlessness was present. In 

 thirteen minutes, this restlessness had become somewhat greater, and the animal 

 had decided difficulty in moving about. Soon afterwards the pupils became still 

 more dilated, and in eighteen minutes they measured ^§ths x J^ths of an inch. 

 In twenty-five minutes, the difficulty in moving about had become greater — 

 even to such an extent that often the anterior extremities yielded, and the rabbit 

 fell on the thorax. It appeared also to be in a somewhat excited state, as con- 

 fused and stumbling movements were frequently made. In fifty-two minutes, 

 the pupils measured i^ths x ^ths of an inch, but no obvious change had 

 occurred in the general condition of the animal. In one hour and ten minutes, 

 however, evidences of recovery were manifested ; the rabbit went about with 

 but little difficulty, no restless excitement was present, and frequently a per- 

 fectly normal sitting posture was assumed. Indeed, the only symptom of an 



