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Old 13th February 2005, 08:01 PM   #25
Jim McDougall
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Location: Route 66
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This thread really is more and more fascinating!!
Yannis: thank you for the additional notes on Magnesia. I did see the reference to both regions when I read the entry in Brittanica, but left out that detail for simplicity in general reference. It seems to me the reference to the Cretan shepherd may likely be apocryphal. As always, I would defer to your outstanding knowledge of your country's history.

Jens: I have read the material on the link referring to Chinese mariners compasses being used some 4500 years ago, but cannot find anything to support the authors statement. Most of my research is based on Encyclopedia Brittanica data which notes (under 'compass') "...there is no genuine record of a Chinese maritime compass before 1297 AD as Kalproth admits".
*"Letire a' M.LeBaron Humboldt sur l'invention de la boussele" J. Kalproth, 1840, p.57 (bossola=It. term for compass, used by Muslims).
The Brittanica states further that the earliest allusion to the power of lodestone in Chinese literature occurs in a Chinese dictionary in 121 AD defining the stone as giving attraction to a needle. There is however myth suggesting a Chinese emperor created a chariot to indicate south (the Chinese compasses focused south, while European north) and the four cardinal directions, c.2634 BC. This period would fall loosely into that suggested in the material noting 4500 year old date, but it would seem that data remains largely subjective.
Naturally more recent research has discovered considerable new material concerning early Chinese maritime history as we have found in the book "1421", so more must be considered before any conclusions can be drawn.

Concerning the use of lodestone in smelting steel:
Robert Elgood in "Arms & Armour of Arabia in 18th & 19th c." on p.107 states. "...Birdwood (1880) wrote that 20 miles east of Nirmal and a few miles south of the Shisha hills occurs the hornblende slate or schist from which the magnetic iron used for ages in the manufacture of damascus steel, and by the Persians for their swordblades is obtained."
"The Industrial Arts of India" G.C.M.Birdwood, London, 1880, p.50

Elgood also notes on p.86 that HH Sultan Ghalib Al Qu'aiti described to him how magnetic quality found in some dagger blades raised the esteem of the blade. He notes that the very best janbiyya and nimsha blades were imported into the Hadhramaut from Hyderabad where they were made. These blades were referred to generally as 'Haiderabad'.

It would seem that magnetite was certainly present in certain wootz from India, although not necessarily in all of it. It is noted that wootz was also of course smelted in Kona Samundrum (southern India) where much of this product was exported particularly to Persia as the raw material in cakes.
It is not specified that any magnetic properties existed in this form of wootz.

I think the observations concerning creating magnetic polarity by filing consistantly as described is interesting, and while certainly non relevant to magnetism, I think it is interesting to note that the force of static electricity also creates the property of attraction in textiles. With the forces of nature, and as we well know in the aviation industry, static electricity can be deadly near volatile materials. On a lesser note, the same force can be maddening for women wearing certain clothing on a dry, windy day .. the dreaded static cling!!

Now ask me as I sit in the rubble of notes and stacked books here in my den, how in the world did I get from ancient Chinese navigational history and the production of steel in India to static cling in womens skirts!!?
I need some rest !!!

Best regards,
Jim
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