588 



Messrs. G. A. Buckmaster and J. A. Gardner. [July 19, 



seven hours the blood still may contain 1 to 2 milligrammes per cent, of 

 chloroform. He also observed that the palpebral reflex reappeared within 

 1J to 2 minutes after anaesthetic periods which lasted 38 and 67 minutes. 

 In one experiment he mentions that the animal got up and walked off the 

 table 30 minutes after the chloroform was stopped, and the animal appeared 

 to be quite normal, though at this period there were 10 milligrammes of 

 chloroform per cent, in the blood. 



In the case of cats, the curves for arterial blood show a general similarity 

 in form to curves which we have constructed from the data given in Mcloux's 

 paper. The initial falls in our curves are not so rapid as in the case of the 

 dog, and the chloroform-content of arterial blood was only reduced by 50 per 

 cent, in about 15 to 20 minutes. In our longest experiments, about three- 

 quarters of the chloroform was eliminated in about 30 minutes, when the 

 animal was breathing normally. When, however, an increased ventilation of 

 the lung is brought about by artificial respiration, a very much shorter space 

 of time is required, as is evident from the analyses quoted in former papers. 



Reflexes in our experiments reappear later than was noticed by Mcloux 

 for dogs ; but though the pinna reflex, corneal reflex, tendon reflex, and tail 

 reflex were noted, there is no definite order in which they reappear, though 

 as a rule the tail reflex is the last. 



Not infrequently an animal goes to sleep during recovery from anaesthesia, 

 but we have never noticed the rapid recovery of volition to which Nicloux 

 has drawn attention. 



According to Tissot's observations, it would appear that during recovery 

 from anaesthesia the amount of chloroform in venous blood constantly exceeds 

 the amount in arterial, as may be seen from the following table constructed 

 from his paper. He also considers that a study of the chloroform-content of 

 arterial blood should be made during the induction of anaesthesia and of 

 venous blood during the disappearance of anaesthesia. 





Cessation of 

 chloroform administration. 



45 minutes 

 later. 



2 hours 

 later. 



\ 



Arterial blood . . . 

 Tenous blood ... 



53-2 

 48-1 



5-8 



7 7 



o-o 



4-9 



All these results we cannot confirm, though in Tables III, IV, and V, 

 which are those of the chloroform-content of samples of arterial and venous 

 blood taken simultaneously, we are in agreement with Tissot's observations 

 that at the moment when chloroform is stopped, arterial blood contains an 

 excess of the drug when compared with venous blood. 



