the way of irritating adjacent fibres? There is an old experiment devised by Matteucci that favours this view. I have two of the usual nerve and muscle preparations connected with these two telegraphs. Call this one A and the other B. I stretch the nerve of A over B, and the nerve of B is placed on the wires of the induction coil. I now irritate the nerve of B, and of course its muscle B contracts;
Fig. 70.—Arrangement to show Matteucci's induced contraction. A, muscle, the nerve of which is placed on B ; G, galvanic element; K, key; P primary and S secondary coil of induction machine.
but you observe the muscle A also contracts. We explain this by supposing that the negative variation change in the muscle B is sufficient to stimulate the nerve of A, and therefore A contracts as well as B. Matteucci, in a similar way, found that a number of muscles might be thus connected, the nerve of the one lying on the muscle preceding it, so that when the nerve
