Electro-physiology and electro-therapeutics : showing the best methods for the medical uses of electricity / By Alfred C. Garratt.

the head. Exhaustion of nervous energy will likewise produce it. Cold will produce it. So will suddenly changed currents of galvanism. This, then, it is highly probable, is an electro-physi- ological phenomenon. Insensibility arises from the same causes that produce giddiness, but it requires a greater degree. In giddiness, the nerve batteries of the brain appear to be disturbed or unbalanced ; but where there is insensibility they seem almost suspended to the last degree. The blood to the brain is defi- cient or deteriorated, and unfit for the purpose, so that the sen- sorium nerve-battery cannot act. No impression can be received or responded to, when the blood is vitiated to a certain degree, as by carbonic acid, chloroform, narcotics, or poisons. It is, perhaps, scarcely necessary to say that this may occur from an organic lesion somewhere between the centre and periphery. Now, if these occur with a state of atony, the iron preparations, with nutritious food, are the best means for restoring the usual constituents of the blood. If in the strumous patient, cod-liver oil will the better reestablish the peripheric portion of the elec- tro-nervous arrangement. In all cases, a judicious employment of electricity, in connection ivilh these other rational means, can be a powerful auxiliary. Effects of Electric Currents on the Muscles respectively. If we electrize the muscles of the face of a person just dead, and while the muscles have retained their natural excitability, we can truly study the mechanism of physiognomical expres- sions, because we can thus excite each muscle, and cause it to contract much the same as when they are put under the action of thoughts, passions, habits, or prevalence of character. The muscles are inclined to retain, during their repose, some degree of the predominance of tonic force exercised most repeatedly and constantly upon them, and this etches or carves in every human face its own peculiar expression and character, which we term physiognomy. Dr. Duchenne has made this subject his very special study, and from him we obtain many highly inter- esting facts. 23