636 SCIENCE PROGRESS 



spectroscopic characters of this body, especially as Kriiger 

 questions the accuracy of many of the existing charts of the 

 spectra of the blood. 



The facts upon which Moore and Roaf rely as proofs that 

 a true compound or aggregation can, and actually does, take 

 place between chloroform and cell-proteins have been elicited 

 by several different methods which were employed for deter- 

 mining the maximum solubility of chloroform in water, salt 

 solution (75 per cent.), serum, haemoglobin solutions, and in 

 blood. The estimated maximum solubility at 13 C. by weight 

 proved that chloroform has a much higher solubility in serum 

 or haemoglobin solutions than in saline or in water. For 

 example, it was found that the following figures might be 

 taken to represent the maximum solubilities : 



Per cent. 



Water '95 



Saline ('75 per cent.) ..... '83 



Serum 5*08-4 



Haemoglobin solutions or blood ... 6 



Determinations of the vapour pressure of chloroform in 

 water, serum, and haemoglobin solutions were also made with 

 a specially constructed differential densimeter. 



It is well known that of the three gases which exist in blood 

 the amounts of oxygen and carbon-dioxide taken up are not 

 proportional to the pressure exerted by these gases ; in other 

 words, their absorption does not follow the Dalton-Henry law. 

 The question whether chloroform is or is not taken up by 

 blood according to this law has never been experimentally 

 tested. A given mixture of air and chloroform possesses a 

 definite chloroform vapour pressure in the mixture. If such 

 a mixture is inhaled, the vapour pressure of chloroform in 

 air at the anaesthetising value is found to be about 8-10 mm. 

 of mercury, which was the value observed by Paul Bert. The 

 evidence given by B. Moore and Roaf, who have measured 

 the vapour pressures of chloroform in water, serum, and haemo- 

 globin solutions of equal strength to that which exists in blood, 

 indicates that the curves of pressures and concentrations in the 

 case of serum and haemoglobin are such that it is clear chloroform 

 cannot be absorbed according to the Dalton-Henry law, but 

 that the drug is actually associated with the blood-proteins 



