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physical cause was veiled as close from their inspection asit is from that of the moderns, who are even now completelyuninformed of its nature, or cause of production.
5. Electric Attraction is said to be the effect of afluid constantly circulating in and collected from the at-mosphere, of so subtle a nature, that it enters the closestforms of bodies, and is communicable to any number ofobjects or to any extent by proper conducting mediums ; ofthis species the lightning is presumed to be composed. Itsconductors are brass, iron, silver, platina, glass and gold ; infact, any close and dense body : whilst its non-conductorsare of the contrary species of substances, i.e. woollen, silk,cotton, or any porous substance. Its effects are so wellknown that nothing more need be added in this place ; andfor further information we refer to the article, and a varietyof others we have already discussed, or propose to dopresently.
6. Galvanic Attraction; for information upon this, wealso refer to a succeeding article, which treats expressly cnits discovery.
Thus we have, we hope, made some arrangement in thedoctrine of attraction, which will not be found in every phi-losophical work, although we only claim what has appearedby way of explication. W ith respect to some other pro-perties of bodies which are observed, it is noticed thattrees have the power to change the direction of their rootsfor nourishment, then to resume their usual direction : thatcertain plants which are wholesome and commonly nutritivedirect their course towards the sun ; whilst others which arenoxious, and sometimes poisonous, pursue a contrary direc-tion.
Magnetism . — Certain bodies have properties peculiarto themselves: thus the loadstone attracts iron and steelonly; which power the Latin name is meant to designate,being derived from may ties, etis, whence the name of thepower is also called Magnetism .
What is very remarkable in this substance is, that itcommunicates its attractive virtue to a piece of steel whenrubbed with it, without losing any of its own properties ;another most peculiar and valuable property is, that if steelbe suspended by a thread, or placed on a pivot, it readilypoints its direction to two cardinal points of the compass,i. e. north and south, whence the other points may be easilydetermined. The importance of the magnet to navigationmay be hence conceived. However, it is reported that incertain situations the magnet has been known to varv, which