418 iiEPOKT — 18G9. 



THE CHLORIDES, 



I have in previous Reports brought forward the properties of the chlorides 

 of methyl and ethyl. The first is an admirable anesthetic, when inhaled in 

 the proportion of 15 per cent. : it ranks in safety next to methylic ether, and 

 a compound made of it with absolute ethylic ether is perfect. The objection 

 to it is that, being a gas, it is not easily manageable. 



Chloride of ethyl stands in the same position as chloride of methj'l ; but 

 the action of it is much more prolonged, and a longer time is required for the 

 production of action. With absolute ether it forms an excellent compound, 

 the objection to which is, simply, its instability. 



The chlorides of butyl and amyl have an action so mucli alike that they 

 may be taken together ; both are simple and effective anaesthetics, and both 

 are pleasant to inhale, the butyl chloride being most agreeable. 



The peculiarity of their action is that the sleep they induce is extremely 

 jjrolonged, this being specially the fact with chloride of amyl. Pigeons when 

 put to sleep by breathing ten per cent, of chloride of amyl pass slowly through 

 the three degrees of anassthetic insensibility^' easily and vsithout convulsion, 

 but invariably with slight vomiting. From ten to twelve minutes of inhala- 

 tion are required to produce perfect sleep, and the temperature of the body 

 falls full four degrees. The sleep once produced wiU continue in the common 

 air at 70° Eahr. for fifteen minutes profoundly. The awakening is quick, and 

 recovery is perfect. 



In rabbits the action is much the same ; seven minutes are required to 

 produce safe narcotism, and the sleep produced is very profound. The 

 breathiijg is tranquil, and the eyes, as is the case from amylenc, usually re- 

 main open. A rabbit will lie fivc-and-thirty and even forty minutes in 

 this state of insensibility before showing signs of recovery, and the tem- 

 perature win fall from 3° to 4° Eahr. If the inhalation be carried too far, 

 the profound sleep I have mentioned passes slowly into death, the sleep 

 being prolonged in the common air at 70° Eahr. a fuU hour and a half prior 

 to death. During this time tlie respiration for the most part is natural, with 

 occasional double breathing ; but the temperature of the body is all the 

 while gradually declining, and is even reduced, while yet the animal is breath- 

 ing, to 21° Eahr. below its natural standard. Thus in one case the temperature 

 of a rabbit fcU from 103° Eahr. to S2° Eahr. This is the lowest reduction I 

 have seen in connexion with symptoms of living action ; but from this extreme 

 condition recovery is possi))le if the respiration be sustained in a warm air. 



After death from the chloride of amyl the heart- is found charged with 

 blood on both sides, and the action of the auricles and ventricles is long per- 

 sistent. The blood is very slow to coagulate ; but the venous and arterial 

 bloods retain their colour. The lungs are natural. The blood- corpuscles are 

 much changed ; they are shrunken, steUate, and elongated, with truncated 

 ends. 



The brain is left bloodless and of the purest white. 



Note on the CnLOEinES. 



The whole of the substances in the chloride series are simple and pure anaes- 

 thetics, and the power of their action obviously increases in proportion as there is 

 increase of cai'1)on. They act most readily and determinately on the cerebrum, 

 and on the centres of volition and common sensibility. They have little action 

 on the organic nervous system, and they interfere, even in full doses, but very 

 gradually ^yitli the movements of tlie heart and respiration. The chlorides 



