EFFECTS OF DIFFERENT GASES
93
without the abolition of its excitability. The effect of the gas is very different when it contains impurities such as sulphuretted hydrogen. I give a record (fig. 51) which
Fig. 50.—Effect of carbon disulphide.
Fig. 51.—Effect of coal gas: note irregularity of response after introduction.
exhibits the depressing effect of coal gas, and the gradual restoration of normal excitability on admission of fresh air.
Chloroform
The vapour of chloroform acts as a very strong narcotic. In the record here given (fig. 52) the response became very