1906.] The Pharmacology of Ethyl Chloride. 411 



to the Society, an investigation into the action of ethyl chloride, by Webster, 

 has appeared in the ' Bio-Chemical Journal,' June, 1906, vol. 1, p. 328. 



In Webster's experiments, as in Cole's, the quantity of ethyl chloride 

 administered was not determined. This observer concludes that — (1) after 

 a preliminary increase, the respiration rapidly diminished in rate and 

 extent ; (2) after a preliminary slight rise, the blood-pressure fell ; (3) no 

 paralysis of vagus endings occurs (in contradiction to Cole) ; (4) the action 

 upon the circulatory system is, almost entirely, directly upon the heart. 



Some of the records illustrating Webster's paper show marked vagus 

 inhibition occurring during the course of the administration of the anaesthetic, 

 but the author does not remark upon this fact.] 



REFERENCES. 



1. McCardie, ' Lancet,' October 7, 1905 ; ' Brit. Med. Journal,' March 17, 1906, p. 616. 



2. Idem, ' Lancet,' 1903, vol. 1, p. 952. 



3. Cole, " The Physiological Action of Ethyl Bromide and Somnoform," ' Brit. Med. 



Journal,' 1903, vol. 1, p. 1421. 



4. Hewitt, ' Lancet, 1904, vol. 2, pp. 1408 and 1486. 



5. Embley, 1 Brit. Med. Journal,' 1902, vol. 1, p. 820. 



6. Embley and Martin, ' Journ. of Physiology,' vol. 32, 1905, pp. 147—158. 



7. Gaskell and Shore, ' Brit. Med. Journal,' January 28, 1893, pp. 165 — 6. 



8. Idem, loc. cit. 



9. Embley, ' Brit. Med. Journal,' 1902, vol. 1, pp. 951—957. 



10. Embley and Martin, loc. cit. 



11. Embley, ' Brit. Med. Journal,' 1902, vol. 1, p. 885. 



12. Idem, loc. cit., p. 957. 



13. Moore and Roaf, 'Proc. Roy. Soc.,' 1904, vol. 73, p. 382. 



EXPLANATION OF FIGURES. 



1 (| size of original). — Isolated heart. Recovery. Dog. Weight, 8 kilogrammes. 

 Morphine, 0'3 gramme and ether for anaesthesia in preparation. Common trunk 

 of right carotid and subclavian arteries ligatured. The left carotid used for 

 the monometer, and the aorta tied just beyond the left subclavian. The 

 left subclavian artery is thus left open to carry the circulation. Its 

 ascending branches and the vertebral arteries are then ligatured. Vagi cut. 

 Artificial respiration. Blood-pressure tracing. Blood-pressure at starting 

 92 mm. Hg, 10 per cent, ethyl chloride vapour in the inspired air at starting 

 " on " continued for 8' 15" and stopped at " off." The blood-pressure fell 

 to 58 mm. The blood-pressure rose to 104 mm. in 9' 35'' after administration 

 ceased. 



2 (f size of original).— Isolated heart. Recovery. Dog. Weight, 8 - 5 kilogrammes. 

 Morphia, 35 grammes and ether for preparation as for experiment in fig. 1. 

 Blood-pressure 158 mm. Hg at starting. Fifteen per cent, ethyl chloride 

 vapour in the air respired started at " on " and continued for 3' 12" and 

 stopped at " off." Blood pressure fell to 63 mm. Hg. In 2' 12" the blood- 

 pressure had returned to 139 mm. 



