312 THE INTELLECTUAL RISE IN ELECTRICITY. 



from error than confusion." Better a wrong hypothesis 

 than none at all. 



But mistakes mislead, and erroneous theories obscure 

 the vision for new discovery. Perhaps for this reason, 

 perhaps because he did not regard them as of sufficient im- 

 portance, in view of the object sought, Gilbert failed to 

 observe many electrical facts which were well within his 

 horizon. He knew nothing of electrical conduction. 

 Magnetic conduction he realized easily under the assump- 

 tion of the change in Form occurring throughout an 

 elongated, magnetized body from one end to the other. 

 But he never carried his electrical effluvia, even in im- 

 agination, through solids, nor, in fact, could he logically 

 do so under his assumption that they were corporeal 

 emanations capable of being dammed by a sheet of paper. 

 He speculated somewhat concerning terrestrial electricity, 

 but only as a means of uniting and holding the earth 

 Matter. Electric repulsion he not only did not observe, 

 but he denies its existence, asserting specifically that 

 "electrics neither repel nor propel." Nor is this notion, 

 for him, inconsistent, in view of his belief that the plac- 

 ing of like magnetic poles together was an unnatural dis- 

 position of them, which nature would proceed to set right. 

 Magnetic repulsion was therefore merely a preliminary 

 rotation of one magnet, so that both might come together 

 " perfectly according to nature.". 



The practical character of Gilbert's work is well indi- 

 cated by the inventions which he makes. Thus he de- 

 scribes the first filar suspension of the needle of an indi- 

 cating instrument, and even advises that silk filaments be 

 used, twisted differently and not all in one direction, so as 

 to eliminate the torsional effect: the first instrumental 

 magnetometer (an iron versorium), and incidentally points 

 out that the stone which from the greatest distance causes 

 the needle to turn, is the best and strongest. He first 

 determined the directive strength of a pivoted magnet, 

 by noting the frequency and extent of its vibrations before 



