STUDY OF THE PHYSICAL CHEMISTRY OF ANAESTHESIA 
157 
produce anaesthesia, how the anaesthesia can be so quickly recovered from when 
administration is interrupted ; for the hypothesis presents no mechanism for the 
rapid restoration of the materials supposed to be removed during anaesthetization. 
The last argument also disposes effectually of any theory whatever which depends 
upon a removal of any permanent element of the cell as a cause of anaesthesia. 
A somewhat reversed theory to that just discussed which has lately gained much 
support was put forward independently and almost simultaneously by Hans 
Meyer 1 and E. Overton. 2 
Instead of ascribing the action of anaesthetics, such as chloroform and ether,' to 
the solvent action of the anaesthetic upon the lipoids of the cell, the basis of the 
theory of Meyer and Overton is that the cell lipoids dissolve or take up physically 
the anaesthetics, by which process the physical properties of the lipoid are altered, and 
in some manner anaesthesia is induced as a result of this alteration in the lipoids. 
The authors leave the manner in which this supposed physical alteration in the 
properties of the lipoids, by the taking up of the anaesthetic, brings about anaesthesia 
an open question. Overton suggests that the lipoids are either unable to carry out, 
in this altered condition, their own functions within the cell, or that the new physical 
conditions of the lipoids acts as a disturbing influence upon the functions of other 
constituents of the cell. 
In regard to the nerve cell, Overton further throws out the surmise that the 
alteration in the condition of the lipoids by the anaesthetic may increase the physio- 
logical resistance to the passage of the stimulus both within the cell, and between one 
cell and another, and also that the activity of the cell to respond when a stimulus 
reaches it may be lessened by the presence of the anaesthetic in the lipoid. 
Although a large number of substances have been examined by Meyer and by 
Overton from the point of view of the relationship of their strength as anaesthetics 
to their relative solubility in water and in olive oil, and it has been demonstrated 
roughly that the relationship exists, that the less soluble any given substance is in water, 
and the more soluble it is in oil, the more powerful it is as an anaesthetic. Yet, it 
may be pointed out, that this by no means settles the matter, for there are other 
substances in the cell than the lipoids, and it must also be shown, before the argu- 
ment gathers any weight, that a similar physical property does not belong to any of 
these, that there are no other substances in the cell which have similar affinities along 
parallel lines for taking up the anaesthetics, and which may be more intimately connected 
with the activities of the cell than the lipoid constituents. 
It is clear that if the anaesthesia be due to any substance whatever in the cell, 
1. Sitzungsber, d. Gesetlsc/i, «. Beforderung d. ges. Naturivissen, Marburg, 1899. Arch. f. exper. Path. 11. Pharm. 
Bd. X C ii, S. 109 ; see also F. Baum. Ibid. S. 119. 
2. Overton, Studien uber die Narkose, G. Fischer, Jene, 1901. 
3. Anaesthetics ot this class are designated as indifferent anaesthetics by Overton in contra-distinction to basic anaesthetics, 
which include such of the alkaloidal anaesthetics as possess basic properties. According to this observer the action of the latter 
class is different in origin, and probably due to interaction with the cell proteids. 
