AN EXPERIMENTAL STUDY OF THE PHYSICAL 
CHEMISTRY OF ANAESTHESIA IN RELATIONSHIP 
TO ITS CAUSATION 1 
By BENJAMIN MOORE, M.A., D.Sc. 
JOHNSTON PROFESSOR OF BIO-CHEMISTRY, UNIVERSITY OF LIVERPOOL 
AND 
HERBERT E. ROAF, M.B., Toronto 
JOHNSTON COLONIAL FELLOW, UNIVERSITY OF LIVERPOOL 
THE production of insensibility by the action of drugs was a source of wonder 
and fanciful speculation to the ancients long before the commencement of 
the modern history ot anaesthesia, and frequently forms the theme of poet, 
dramatist, or novelist. 
It is hence not to be wondered at that in more recent times it has powerfully 
stirred the imagination and the interest of scientific workers who have sought, by 
theory and experiment, to account for the profound effects produced upon living 
structures by such chemically indifferent and inert substances as are most anaesthetics. 
The first fact which appealed to the earlier observers was the similarity between 
anaesthesia and sleep, and experimentation was accordingly directed towards the 
discovery of points of similarity between the two conditions. The variation of blood 
supply to the brain by the varying calibre of the small arterioles was a common 
explanation early offered for both sleep and anaesthesia. 
Durham, 2 in i 860, demonstrated by direct observation made after trephining, that 
the brain surface was paler and hence more anaemic when sleep came on, and flushed 
again when awakening occurred, and so disposed of the older theory which had never 
been supported by experiment that sleep was ciue to a hyperaemia of the brain. 
1. The experiments here recorded have formed the basis ot a previous communication to the Royal Society, published in 
Proc. Roy. Soc, Vol. 73 (1904), p. 382. We have to thank the Royal Society for permission for their republication with the 
accompanying illustrations. The expenses connected with the research have been paid by a grant allotted for the purpose from 
the Government Grant to the Royal Society. 
2. Arthur E. Durham, The Physiology of Sleep, Guy's Hospital Reports, Third Series, Vol. 6 (i860), p. 149. 
