Page:Life in Motion.djvu/167

Rh isolated muscles of frogs, and to some extent were vitiated by the conditions in which the muscles were examined.

To illustrate what is meant by the work of a muscle, I show you here an interesting experi-

ment carried out by an ingenious instrument devised by Professor Fick, and which he calls the Arbeitssammler, the work-gatherer. It is a little windlass or capstan, which you see is turned by a frog's muscle placed above it, and