STUDY OF THE PHYSICAL CHEMISTRY OF ANAESTHESIA 161 
further, that this combination was not a stable fixed one, leading to permanent removal 
of the protoplasmic activity, but an unstable one, which existed only so long as the 
pressure of the anaesthetic was kept up to a definite level, and gradually dissociated 
as the level of chloroform pressure was allowed to fall, and as a result lett the proto- 
plasm free tor a renewal of its metabolic processes — to choose a familiar analogy, 
that the protoplasm of a cell undergoing anaesthetization entered into a combination 
Avith the anaesthetic, similar to that between haemoglobin and oxygen, unstable in 
character, and only lasting so long as the pressure of the anaesthetic was kept up. 
It occurred to us, as protoplasm is built up chemically of proteid, that a certain 
amount of evidence as to the formation of such an unstable compound might be 
obtained, in the first instance, by experimenting with proteids. 
We accordingly experimented with the proteids of the blood, and have obtained 
a number of results which together point to the formation of such compounds as are 
indicated above. 
Our experiments may be described under the following headings : — 
1. On the obvious physical and chemical changes produced in serum and in 
haemoglobin solution by the addition of chloroform. 
2. On the relative solubility of chloroform in water, normal saline solution, 
serum, and haemoglobin solution. 
3. On the relative vapour pressures of chloroform when dissolved in water, 
saline, serum, and haemoglobin solutions respectively, and on the variations in the 
coefficient of distribution in these solutions. 
4. On the solubility of gases in serum and haemoglobin solution in presence 
of chloroform. 
5. On the solubilities of other anaesthetics in water and in serum 
respectively. 
I. — Effects of Chloroform on Serum and on Haemoglobin Solution 
On adding chloroform' to either serum or haemoglobin solution and allowing 
the mixture to stand, changes occur which are obvious to the eye, and were to us 
previously unknown, but on consulting the literature we found that they had been 
observed by E. Salkowskt in using chloroform as a preservative for these fluids, and 
were also described by Formanek, 3 the bearing of such phenomena upon the ques- 
tion of anaesthesia was not, however, appreciated by these previous observers, who 
had approached the matter from a different standpoint, and as we have in some 
respects amplified their observations, and in others have obtained results not quite 
in accord with theirs, we feel justified in here recording our experiments. 
1. The chloroform used for all the experiments described in this communication was presented to us bv Messrs. Duncan 
and Flockhart, of Edinburgh. 
2. Deutsche Med. Wochemch., 1888, No. 16 ; ZeitscA.f. phyuol. Chem., Bd. XXXI, 1900, S. 329. The fact that the red 
corpuscles combine with chloroform is also mentioned by Schmiedeberg, Arch. f. Heilkunde, 1867, S. 273. 
3. Zeitsch.f. phyuol. Chem., Bd. XXIX (1900), S. +16. 
W 
