Page:On the various forces of nature and their relations to each other.djvu/138

strongly to allow itself to be lifted up—so wonderful is its power of attraction. If you take a needle, and just draw one of its ends along one extremity of the magnet, and then Fig. 39.draw the other end along the other extremity, and then gently place it on the surface of some water (the needle will generally float on the surface, owing to the slight greasiness communicated to it by the fingers), you will be able to get all the phenomena of attraction and repulsion, by bringing another magnetised needle near to it.

I want you now to observe, that although I have shewn you in these magnets that this double power becomes evident principally at the extremities, yet the whole of the magnet is concerned in giving the power. That will at