24 
POPULAR SCIENCE REVIEW. 
mentioned above, was nothing less than impure chloroform. 
Mr. Jacob Bell, of London, it appears, was the first to procure 
it in a pure state, and demonstrated anew its wonderful anaes- 
thetic properties. As early as 1831, Dr. Gutherie, an American 
chemist, had shown that this substance is procured when spirit 
of wine is distilled with chloride of lime. But its true chemical 
composition, which had puzzled Professors Silhman, Liebig, 
and Soubeiran, was finally determined by Professor Dumas, of 
Paris, in 1832. 
On the 8th of March, 1847, M. Flourens stated, at the Paris 
Academy of Sciences, that he had experimented with chloro- 
form upon different animals, and had ascertained that it 
invariably produced insensibility; but he concluded that its 
action was too dangerous to be applied to man. However, in 
November of the same year. Professor Simpson, of Edinburgh, 
applied chloroform, for the first time, to annul the pains of 
labour, and it has since completely dethroned ether in surgical 
operations.* 
Dr. Gregory, of Edinburgh, afterwards showed that the 
action of ether and chloroform is precisely similar to that of 
nitrous oxide gas. When either of the two former is inhaled 
in insufficient quantity, the patients are given to laughing, 
dancing, &c., as if they had respired a dose of “ laughing- 
gas.” 
It is certainly wonderful, when we reflect upon the fact, that 
these volatile liquids, whilst rendering us insensible to pain, 
cause the patient to experience pleasant sensations whilst under 
the knife of the surgeon. Before referring to any other means 
of rendering man insensible to suffering, let us take a rapid 
glance at the manner in which these remarkable amesthetics 
act upon the system. 
Under the influence of chloroform and ether, the nervous 
centres lose their powers in regular succession. This is not 
only an interesting physiological fact, but also a practical point 
of great importance. First, the cerebral lobes lose their influ- 
ence, and consciousness disappears entirely. Next, the cere- 
bellum loses its power of regulating locomotion. Next, the 
spinal cord becomes incapable of producing sensation and of 
originating motion; but the medulla oblongata (that portion of 
the spinal cord which enters the brain), which presides over 
respiration, still retains its functions. Next, the medulla 
oblongata is affected ; when this occurs breathing ceases, and 
* Ether has often been applied with success to subdue intoxication by 
wine, as we see the betel-nut employed by the Eastern princes to dispel the 
effects of haschish ; after inhaling a little ether vapour, the intoxicated person 
generally recovers his senses. Ammonia acts in a similar manner. 
