86 



On certain Physical and Chemical Properties of Solutions of 

 Chloroform and other Ancesthetics. — A Contribution to the 

 Chemistry of Ancesthesia. (Second Communication.)* 



By Benjamin Moore, M.A., D.Sc., Johnston Professor of Bio-chemistry, 

 University of Liverpool, and Herbert E. Boaf, M.D., Toronto, Johnston 

 Colonial Fellow, University of Liverpool. 



(Communicated by Professor C. S. Sherrington, F.R.S. Eeceived October 19, — 



Bead November 23, 1905). 



In a previous communicationf we have shown (1) that chloroform has a 

 much higher solubility in serum or haemoglobin solutions than in water or 

 saline ; (2) that at the same vapour-pressure of the chloroform the amount 

 dissolved in serum or haemoglobin solution is considerably higher than in 

 saline or water; (3) that the curve of chloroform vapour-pressure and 

 concentration in solution in the case of water and saline is a straight line, 

 while in the case of serum and haemoglobin solution it is a curve showing 

 association at the higher vapour-pressures ; (4) that in the case of serum 

 addition of chloroform causes an opalescence and a slow precipitation at room 

 temperature (15° C), and at body temperature (40° C.) a rapid, though 

 incomplete, precipitation, also in the case of haemoglobin, 1*5 to 2 per cent, of 

 chloroform causes a change of colour and commencing precipitation at room 

 temperature, which becomes almost complete in the thermostat at 40° C, 

 while 5 per cent, and over causes complete precipitation, even at 0° C. 



In our previous paper we also recorded the relations between chloroform 

 vapour-pressure and concentration of the anaesthetic in solution for water, 

 saline and serum, throughout a range from below the anaesthetising value to 

 nearly saturation, and gave curves illustrating these relationships. 



From these experiments we drew the conclusion that chloroform forms an 

 unstable chemical compound or physical aggregation with the proteids experi- 

 mented upon, and that it is carried in the blood in such a state of combina- 

 tion. Since proteids build up the living protoplasm, the inference was drawn 

 that chloroform and other anaesthetics must form similar unstable compounds 

 with protoplasm, and that anaesthesia is due to the formation of such 

 compoimds, which limit the chemical activities of the protoplasm. On 

 account of the instability of the compounds, these remain formed only so 

 long as the pressure of the anaesthetic in the solution is maintained. 



* Part of the expenses of the investigations have been defrayed by a grant from the 

 Eoyal Society (Government Grant). 



t 4 Eoy. Soc. Proc.,' vol. 73, 1904, p. 382. 



