Page:On the various forces of nature and their relations to each other.djvu/193

Rh motion. The moment we give motion to this soft iron in front of the magnet, we get a spark. It is true, in this apparatus it is very small, but it is sufficient for you to judge of its character. It is the magneto-electric light; and an instrument has been constructed, as there shewn (fig. 59), which represents a number of magnets placed radially upon a wheel—three wheels of magnets and two sets of helices. When the machine, which is worked