Page:On the Magnet - Gilbert (1900 translation of 1600 work).djvu/140

orbicular stone, whose poles are A and B; an iron wire CD, which is placed upon the stone, always points directly along the meridian toward the poles AB, whether the centre of the wire is on the central line or æquator of the stone, or on any other part situated between the æquator and the poles, as at H, G, F, E. So the cusp of a versorium on this side of the æquator points toward the north; * on the other side the cross is always directed toward the south; but the cusp or lily does not, as some one has thought, turn toward the south beyond the æquator. Some inexperienced people indeed, who in distant parts beyond the æquator have seen the versorium sometimes become more sluggish and less prompt, thought that the distance from the arctick pole or from the magnetick rocks was the cause of this. But they are very much mistaken; for it is as powerful, and adjusts itself as quickly to the meridian or to the point of variation in the southern as in the northern parts of the earth. Yet sometimes the motion appears slower, namely, when the supporting pin by lapse of time and long voyaging has become somewhat blunt, or the magnetick iron parts have lost, by age or rust, some of their acquired vigour. This may also be shown experimentally by the versatory iron of a small sun-dial placed on a very short pin set perpendicular to the surface of the stone, for the iron when touched by a loadstone points toward the poles of the stone and leaves the poles of the earth; for the general and remoter cause is overcome by the particular and powerful cause which is so near at hand. Magnetick bodies have of themselves an inclination toward the position of the earth and are influenced by a terrella. Two equal stones of equal strength adjust themselves to a terrella in accordance with magnetick laws. The iron conceives vigour from the loadstone and is influenced by the magnetical motions. Wherefore true direction is the motion of a magnetick body in regard to the verticity of the earth, the natures of both agreeing and working together toward a natural position and unity. For indeed we have found out at length, by many experiments and in many ways, that there is a disposing nature, moving them together by reason of their various positions by one form that is commonto