The Experimental and Historical Foundations of Electricity - Unicamp

Figure 2.8: William Gilbert (1544-1603).
on the other hand, presented the idea that the Earth is a huge magnet and thus
has magnetic properties. He then explained the orientation of the magnetic
needle by its alignment with the magnetic poles of the Earth. 17 In the second
chapterofhisbook,Gilbertdescribedseveralelectrostaticexperimentsthatwere
performed in order to distinguish the phenomena associated with the magnets
from those associated with the amber: 18
Of this substance [the amber] a few words must be said, to show
the nature of the attachments of bodies to it, and to point out the
vast differences between this and the magnetic actions; for men still
continue in ignorance, and deem that inclination of bodies to amber
to be an attraction, and comparable to the magnetic coition.
He called electrics the bodies which had the same property as amber, our
emphasis in italics: 19
The Greeks call this substance �������� [electron or amber], because,
when heated by rubbing, it attracts to itself chaff; [...] These
several bodies (electrics) not only draw to themselves straws and
chaff, but all metals, wood, leaves, stones, earths, even water and
oil; in short, whatever things appeal to our senses or are solid: yet
we are told [by several ancient authors] that it attracts nothing but
chaff and twigs.
17 [Kel81].
18 [Gil78, p. 27].
19 [Gil78, p. 27].
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