Electro-physiology and electro-therapeutics : showing the best methods for the medical uses of electricity / By Alfred C. Garratt.
294/740

(Esophagtts. It is now known, from experimental demonstration and from results in practice, that electric currents here produce marked contractions, both in the longitudinal and circular- fibres of the contractile fibre-cells, or of muscle fibres, or both. At least, such contractions are produced in the oesophagus, whatever be the nature of the structure that contracts. It is said that the oesophagus of most birds consists exclusively of fibre-cells; therefore we account for the motions produced by electricity in the throats of birds, beginning slowly, and lasting after the cur- rent is opened. But there are some birds, as the rodentia, or gnaioers, such as the eagle, vulture, and parrot, whose oesopha- gus consists of animal muscle mainly, or only; and hence, when such are electrized, there are seen prompt and powerful contrac- tions, and at the opening of the current there is as instantaneous dilatation. But this does not obtain so clearly in man, because in the human species, as in almost all mammalia, the oesophagus consists of both organic fibre-cells, and of animal muscular fibres. Hence, when the electric current touches the oesopha- gxis directly or indirectly, the effects are both prompt and pro- longed ; i. e., they partake of the mixed phenomena arising from the contractile fibre-cells and from muscular fibre. If the action of the electric current be prolonged a little, or is made a little stronger, then the contractions are not limited to the throat only, but extend to the stomach.