Page:The fairy tales of science.djvu/36

16 sky were supposed to come from the hand of the mighty Thunderer, and those fiery meteors which now and then rested on the javelins of the Roman legionaries, were looked upon as omens of victory sent by the War-god.

It was left for modern philosophers to trace these great phenomena to the Amber Spirit, and to show that his presence may be detected, not only in the fossil gum which Thales imagined to be his favourite haunt, but in every particle of dust and every drop of water.

Let us now describe the cunning means which man employed to enslave this wild Spirit. Two hundred years ago, the fragments of amber were laid aside, and a large globe of sulphur was set whirling on a vertical axis, whilst it was rubbed by the hand. By this machine the Spirit was dragged from his hiding place, and made to reveal some important secrets. Flashes of light issued from this revolving globe, and balls of pith, feathers, and straw danced towards it as though endowed with life.

Sixty years later, the discovery was made that all solid bodies may be divided into two great classes, namely, those which, when held in the hand and rubbed, set free the Amber Spirit; and those which, under similar circumstances, fail to exhibit any attractive force. Amber, sulphur, and glass belong to the first class; all the metals to the second. It was also found that certain bodies allowed the Spirit to pass along them with great