136 ON ANAESTHETICS 
used in the same form at St. Bartholomew’s Hospital, in preference to sulphuric 
ether, by Mr. Lawrence in the summer of 1847.’ In the autumn of that year 
Dr. (afterwards Sir James Y.) Simpson, who was engaged in a series of experi- 
ments with various narcotic vapours, employed for the first time the active 
principle of chloric ether, at the suggestion of Mr. Waldie, of the Apothecaries’ 
Hall of Liverpool ;* and finding that the pure chloroform was more potent 
than sulphuric ether, yet caused less bronchial irritation, while its odour was 
more agreeable, and its inferior volatility rendered its exhibition more easy,* 
he zealously recommended it to the profession, and it has since been generally 
employed throughout Europe. 
The effects produced by chloroform are such as to fit it remarkably for the 
purposes of the surgeon. Like most narcotics, it tends to cause, after tem- 
porary excitement, suspension of the functions of the nervous centres, but 
affects them not simultaneously, but in a certain order; and the brain is the 
first to show loss of power in failure of sensation and voluntary motion. If 
this were all, anaesthesia would be a questionable boon, as the work of the 
surgeon would be interrupted and often marred by involuntary struggles on 
the part of the patient. But very soon the spinal cord also is subdued, and 
the reflex functions of the cerebro-spinal axis are abolished so far as concerns 
the voluntary muscles, which consequently lie perfectly relaxed and passive, 
better suited for operative purposes than the most resolute will could render 
them. To this, however, there is one remarkable exception, viz. that the parts 
concerned in the respiratory movements remain active; and the same is the 
case with the sympathetic ganglia of the heart. In other words, when the 
administration of chloroform is carried to a certain point, the nervous system 
is deprived of such powers as would cause pain to the patient or inconvenience 
to the surgeon, but retains intact the faculties essential to life. 
There are, however, yet other advantages derived from the inactivity of 
the cerebro-spinal centre. It seems now clearly established that the cessation 
of the contractions of the heart in the shock of injury depends upon an action 
of the brain and cord upon the cardiac ganglia through the medium of the vagus 
and sympathetic nerves; and chloroform, rendering this action impossible, 
protects the heart from the indirect effect of external violence. In this way 
it has greatly diminished the risk of death upon the operating table, and also 
* Snow on Anaesthetics, p. 20. That chloric ether was employed at St. Bartholomew’s Hospital 
has been further confirmed by information kindly communicated to me by Mr. (now Sir James) Paget. 
* Snow on Anaesthetics, pp. 21, 22; also Dr. Simpson’s original pamphlet, Account of a New 
Anaesthetic Agent, &c., p. 6. 
* For operations performed by artificial light, chloroform has another advantage over ether, in 
the fact that its vapour is not inflammable. 
