626 SCIENCE PROGRESS 



chloroform has been under the consideration of a special 

 committee appointed by the British Medical Association.* 

 The experimental work thus initiated has proved of much 

 service, especially in indicating the limit-value of the chloroform 

 vapour which can be safely inhaled. The introduction of an 

 inhaler by Vernon Harcourt for the administration of chloro- 

 form with safety is also the direct outcome of this work. The 

 simplest and quickest way to determine the percentage of 

 chloroform vapour in air is by a method suggested by Waller,^ 

 which depends upon the proportional increase in weight which 

 known volumes of air and chloroform exhibit, compared with 

 the same volume of air. The purpose of this paper, however, 

 is to draw attention to recent work on chloroform anaesthesia 

 which has been carried out in this country and in France. The 

 activity of observers in Germany has not been directed to this 

 particular inquiry. 



Besides chloroform, some hundreds of substances have been 

 shown to possess in different degrees well-marked anaesthetic 

 and narcotic properties. All forms of life, the simplest and the 

 most complicated, unicellular and multicellular organisms, 

 can be shown to exhibit very similar phenomena in response 

 to minute, moderate, and toxic doses of those drugs which are 

 grouped as anaesthetics ; and it is probable some single 

 fundamental type of interaction which takes place between 

 the anaesthetic and the protoplasm or bioplasm of cells, will 

 be found to take place, and that upon this fact a rational 

 explanation of the anaesthetic process will be given. The 

 condition finally established by increasing any given anaesthetic 

 is one of profound intoxication, and a state of narcosis is 

 induced in the higher animals, owing to the successive inter- 

 ference with the excitability of the cortex of the brain, of the 

 grey matter of the spinal cord, and of the grey matter of the 

 spinal bulb or medulla oblongata. These parts of the central 

 nervous system become inactive, and a progressive paralysis 

 of the nerve cells becomes established, in which the sensory 

 and receptive apparatus is probably impaired before the motor. 

 It is beyond dispute, as any one must admit who is familiar 

 with the subject, that the anaesthetic state is a condition where 



' British Med. Journal, July 12, 1902, July 18, 1903, July 23, 1904, July 22, 1905, 

 July 14, 1906, 



^ Waller, Proc. Physiological Soc. 1903. 



