An American text-book of physiology . of metal by which contact be-tween the two ends of the wires may be madeas in a (Fig. 8), or broken as in 6, and thecurrent be sent through the nerve, or preventedfrom entering it. By the latter method thebattery is all the time connected with theelectrodes, and the key acts as a movablebridge between the wires, and when closed gives a path of slight resistance by whichthe current can return to the battery without passing through the nerve. The currentalways takes the path of least resistance, and so, if the key be closed as in c, all the cur-rent will pas
An American text-book of physiology . of metal by which contact be-tween the two ends of the wires may be madeas in a (Fig. 8), or broken as in 6, and thecurrent be sent through the nerve, or preventedfrom entering it. By the latter method thebattery is all the time connected with theelectrodes, and the key acts as a movablebridge between the wires, and when closed gives a path of slight resistance by whichthe current can return to the battery without passing through the nerve. The currentalways takes the path of least resistance, and so, if the key be closed as in c, all the cur-rent will pass through the key and none will go to the nerve, which has a high resistance,whereas if the key be opened as in </, the bridge being removed, all the current will gothrough the nerve. It is often better to let the cell or battery work a short time and toget its full strength before letting the current enter the nerve, and the short-circuiting keypermits of this. Moreover, there are times when a nerve may be stimulated if connected. Fig. 7.—Electric key.
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Keywords: ., bookautho, bookcentury1800, bookdecade1890, booksubjectphysiology
