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

Galvani, Volta, and Yalli, contended that muscular contrac- tions were rendered most strong from the immediate contact of the metallic stimulus to the cut and raw surface of the muscle, without touching the nerve. But others, as Baron Humboldt and Dr. Fowler, thought that such test could never si give a fair solution of the sf question since it is almost impossible to eradicate all nerve fibrils from muscle fibres. They, therefore, were led to conclude that irritability is a property of nerve and muscle as a compound structure. Dr. Marshall Hall announced the same opinion some fifty years afterwards.f Whether the property of irritability belongs to the pure and isolated muscular fibre, or to the muscle fibre combined with the nerves, he thought, could not be positively de- termined by distinct experiment; and that irritability belonged, in all probability, to the compound structure. The law of Yalli and Ritter, which is a confirmed fact in pathology, is in truth the greatest hindcrance to determining this yet unsettled question. That law is, " The nerves may die in Fig. 49. A View of Elementary Fibres of Voluntary MuhcIcs; i. e., of animal life, magnified three hundred diameters, showing a cleavage under slrain, both lengthwise nnd transverse. This also shows that lame- ness from strained muscles may result from ruptured fibres.* * 1. The longitudinal cleavage, also showing the molecular structure. 2. The transverse cleavage. 3. Incomplete fracture of a muscle fibre, following the opposite surfaces of a disk, which stretches across the interval, and retains the two fragments in connection. 4. Shows another disk, nearly detached, as often seen. 5. A detached disk of molecules, still more highly magnified, showing the sarcous element of muscle fibres. 6. Fibrillee separated by the effects of violence from each other at the torn end of the muscle fibre. 7. 8. The two appearances, commonly observed under the microscope, by the single Fibrillte. At 7 they are more highly magnified and appear rectangular ; but at 8 the borders are rounded, and the spaces are bead-like. t Cyclopaedia of Anatomy and Physiology, vol. iii. p. 29, 1847.