STUDY OF THE PHYSICAL CHEMISTRY OF ANAESTHESIA 
In the case of blood or haemoglobin solution, it is difficult on account of 
precipitation to estimate with any approach to accuracy the maximum amount of 
chloroform taken up, but six per cent, by weight may be added, and if rapidly shaken 
up is found to disappear so completely that no globules of chloroform can be found 
among the haemoglobin precipitate on careful microscopic examination. It has also 
been shown that a number of other anaesthetics have a much higher solubility in 
serum than in water. 
3. That, tor the same pressure of the anaesthetic at all concentrations, the 
amount of chloroform dissolved in serum or haemoglobin solution is considerably 
higher than in saline or water. Or, put in another form, at the same concentration 
of the anaesthetic in solution the pressure of the anaesthetic in a vacuum or air space 
is much less in the case of serum or haemoglobin solution than in the case of saline 
or water. 
This has been shown for chloroform in concentrations varying from below the 
anaesthetization value to near the saturation point, and it has further been shown that 
while the curve of pressure and concentration in the case of water and saline is a 
straight line ; in the case of serum and haemoglobin solution it is a curve showing 
association at the higher pressures. 
The coefficient of distribution for chloroform at the anaesthetizing pressure 
(8-10 m.m.) and at _|.o u C. is, approximately, 4-6 tor saline and 7-3 tor serum, and at 
1 5 0 C. these coefficients become 8'8 and 17-3 respectively. 
4. The powers of haemoglobin and of serum for dissolving gases are not 
appreciably affected by the presence of the anaesthetic. 
We believe that the experiments recorded above justify the conclusion that 
chloroform forms an unstable chemical compound or physical aggregation with the 
proteids experimented with, and that it is carried in the blood in such a state of 
combination. Since proteids build up the protoplasm of living cells, anaesthesia must be 
due, in our opinion, to the formation of such compounds which limit the chemical 
activities of the protoplasm. At low pressures of the anaesthetic, the compounds are 
unstable, and remain formed only so long as the pressure of the anaesthetic in the 
solution is maintained. Such compounds are formed not only by haemoglobin but 
by serum proteid, and hence the position taken by the anaesthetic in haemoglobin is 
not that of the respiratory oxygen. This is further shown by the fact that the 
oxygen-carrying power of haemoglobin is not interfered with in presence of chloro- 
form. 
Preliminary experiments with brain tissue and with cardiac muscle, both freed 
from blood, have demonstrated to us that these tissues possess a similar affinity for 
chloroform, as shown both by the higher solubility of chloroform in them, and at 
