374 CHLOROFORM 



phosphorus. Morphine, strychnine, and atropine, singly 

 and in combination, were administered subcutaneously to 

 various subjects before the chloroform was inhaled. The 

 drug was given with and without an inhaler, and in 

 almost every conceivable way. 



Notwithstanding these different conditions, the train of 

 effects followed in regular order. Preliminary excitement, 

 with more or less struggling, occupied from one to two 

 minutes, but gradually gave place to increasing insensi- 

 bility, unconsciousness, and muscular relaxation. Fuller 

 anaesthesia, suitable for the performance of operations, was 

 reached in two or three minutes from the beginning of in- 

 halation, breathing became quiet and regular, blood-pressure 

 was slightly lowered, and reflex actions were impaired and 

 abolished. When the effects were further pushed, respira- 

 tion ceased in six or seven minutes from the commencement 

 of the experiment. About one and a third minutes later, 

 the pulse, after being greatly quickened, ceased ; while 

 two or three minutes later the heart itself stopped. In no 

 case did the heart stop before the breathing. Even when 

 poisonous doses were used, two to six minutes elapsed 

 between the time that respiration ceased and the heart 

 stopped. A somewhat shorter interval occurred, however, 

 in two cases, in which the inhalation was very slow and 

 prolonged ; in four cases, complicated with asphyxia ; and 

 in ten cases, in which morphine, atropine, or strychnine 

 had been previously injected subcutaneously ; but even in 

 these sixteen cases the heart continued to beat for one 

 minute after respiration ceased. Even in those animals 

 debilitated by twenty-four hours' fasting, by blood-letting, 

 or by fatty degeneration of the heart caused by phosphorus, 

 the pulse and heart continued to beat after respiration 

 ceased. Neither serious surgical operations nor bruising 

 of delicate parts during full anaesthesia, or even while the 

 animal was partially conscious, produced syncope or notable 

 direct action on the heart. 



These experiments testify that chloroform may be admin- 

 istered to animals with perfect safety, provided there is no 

 interference with breathing. They further indicate that the 

 large proportion, if not all, the fatalities from chloroform 



