THE MAGNETIC NEEDLE. 51 



.sented during the dynasty of the Tscheu, 1100 years before 

 our era, to the ambassadors of Tonquin and Cochin-China, 

 to guide them over the vast plains, which they would have 

 to cross in their homeward journey. The magnetic waggon 

 was used as late as the loth century of our era. 64 Several 

 of these waggons were carefully preserved in the imperial 

 palace and were employed in the building of Buddhist mon- 

 asteries in fixing the points towards which the main sides 

 of the edifice should be directed. The frequent application 

 of magnetic apparatus gradually led the more intelligent 

 of the people to physical considerations regarding the nature 

 of magnetic phenomena. The Chinese eulogist of the mag- 

 netic needle, .Kuopho (a writer of the age of Constantine the 

 Great), compares, as I have already elsewhere remarked, th^ 

 attractive force of the magnet with that of rubbed amber. 

 This force, according to him, is " like a breath of wind 

 which mysteriously breathes through these two bodies, and 

 has the property of thoroughly permeating them with the 

 rapidity of an arrow." The symbolical expression of " breath 

 of wind " reminds us of the equally symbolical designation of 

 soul, which in Grecian antiquity was applied by Thales, the 

 founder of the Ionian School, to both these attracting sub- 

 stances ; soid signifying here the inner principle of the mov- 

 ing agent. 65 



54 Humboldt, Asie Centrale, t. i, p. xl xlii, and Examen Crit. de 

 VHist. de la Geographic, t. iii, p. 35. Eduard Biot, who has extended 

 and confirmed by his own careful and bibliographical studies, and with 

 the assistance of ray learned friend Stanislas Julien, the investigations 

 made by Klaproth in reference to the epoch at which the magnetic 

 needle was first used in China, adduces an old tradition, according to 

 which the magnetic waggon was already in use in the reign of the Em- 

 peror Hoang-ti. No allusion to this tradition can, however, be found in 

 any writers prior to the early Christian ages. This celebrated monarch 

 is presumed to have lived 2600 years before our era (that is to say, 

 1000 years before the expulsion of the Hyksos from Egypt). Ed. Biot 

 fur la direction de I' aiguille aimantee en Chine in. the Comptes rendus de 

 TAcad. des Sciences, t. xix, 1844, p. 822. 



55 Cosmos, vol. i, p. 182. Aristotle (de Anima, i, 2) speaks only of 

 the animation of the magnet as of an opinion that originated with 

 Thales. Diogenes Laertius interprets this statement as applying also 

 distinctly to amber, for he says, " Aristotle and Hippias maintain as to 

 the doctrine enounced by Thales." . . . The sophist Hippias of Elis, 

 who flattered himself that he possessed universal knowledge, occupied 

 himself with physical science and with the most ancient traditions of 



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