Magnetic weapons

[Jim McDougall]

Hi Ann,
That is exactly what is great! You are able to discuss material that is typically pretty involved and technical and integrate fascinating historical data, which makes it possible to understand
The original course of this thread was to try to discover how extensively lodestone was involved in the wootz in blades. In some of the material we discovered it seems that it inadvertantly occurred in the raw material from Hyderabad, which remained in certain janbiyya blades found in Arabia.

The ensuing discussion here has been fascinating, and I think I've learned more than in any science class I ever took! ( as far as I can remember...the little red schoolhouse ya know!!

Gene,
You better not bail out on us here!!! You have been doing an incredible job of scientific experimentation, I think the first of this type I can recall. What you are doing presents some excellent hands on perspective for some of the somewhat complex ideas that have come up. Thank you for following through on this !!! Outstanding work!

All the best,
Jim

[Jens Nordlunde]

Gene, you are doing excellent with the compasses – tell me did you empty the shop ?
Allow me just one question, when you show the blade with the compasses, it seems as if the magnetism north-south is farther away from each other than the magnets on the knife holder – is that so?

Jens

[Mare Rosu]

JENS
You are very astute MR. JENS
I failed to take a picture of the knife on the magnetic holder at the tip end.
I placed the knife on the holder in two different places that is why you see two areas of magnetic fields and not just the one, both times were approximately five minutes each time with the tip end placement being the last one.
I thing the Case knife picture was different in that the knife profile came out very well while on the Mysore dagger just the magnetic fields are shown.
You ask about the compasses, yes I had to go to two different stores to get them, I tried to get all of them to be the same but could not find four just alike.
One other thing JENS, is that if you look closely at the Mysore dagger with the four compasses on the blade you will see that the tip end compasses is pointing North not South. I do not know why that happened as I did not notice it myself until I posted the pictures, another mystery on the never ending quest for information on Magnetic Weapons!
JIM
I thank you for your comments and will of course stay around as this thread is now becoming a college course for the uninformed (me).
With folks like you and ANN, as well as RIVKIN and I must also add
FEARN for his input/suggestions ( I think he is getting all of his "smarts" from his mother! ) it is hard not to learn from all of this. I also think it is a very interesting subject and not well understood. I do "blame" all of this on JENS, why cant he just read an not ask all of these hard questions?
Gene

[Ann Feuerbach]

This is all such great stuff. It will take me awhile to absorb it all and figure out what it all means! I got someone lined up with homemade ingots any suggestions of how to test them? RIVKIN could you suggest any suitable methods?

[Jens Nordlunde]

Gene, you really had me laugh aloud, I guess that you did not get a discount price, since you had to buy them in two different stores – if you ‘only’ buy two or three compasses a one store, it is harder to discuss the price – although I think a camel dealer would have .

Ann, would it be possible for you to show a picture of one of the ingots?
If it looks like I think, it is like round bread, being thinker in the middle. Would that not make a difference when trying to make them magnetic? Also, if the ingot is round, how would the magnetism be at the ‘sides’? Would it not be different if it is longish ?

Jens

[Mare Rosu]

JENS
I have an wootz ingot and it is round/dome shaped, and I will take a picture of it and I also have a broken flat wootz bar/ingot all gotten from Artzi and I take a picture of that one also.
ANN
let me know what you want me to do as for as applying a compass on them,( I do have a supply of them! )
The bars/ingots have not be subjected to any magnetic fields by me.

I am glad to have you at bat as you sure are one heavy hitter .
Gene

[B.I]

this post is way over my head, but am enjoying the non-participating observation.
dr ann, its great to have someone of your knowledge and passion on board. i am assuming from your article, knowledge and background that your doctrate is related to your current studies. the only reason i ask, is that i have this knee problem in cold weathers....
gene, you dont fail to bowl us over with your ingenuity. not sure what you'll come up with next, but will hide in case there are explosions.
well done jens, for starting and carrying this discussion. i still havent got a clue whats going on but its all fun!

[Rivkin]

Originally Posted by Ann Feuerbach

This is all such great stuff. It will take me awhile to absorb it all and figure out what it all means! I got someone lined up with homemade ingots any suggestions of how to test them? RIVKIN could you suggest any suitable methods?

The problems I see is that:
1. The magnetization depends on two unknown factors - how non-uniform the steel is and what kind of fields the sample was exposed to. Lighting, wielding machines and subways all produce significant fields, capable of magnetizing pieces of iron.

So at least two different experiments should be condacted, unless you are interested in non-uniformities alone. Then the reasonable thing is to ask a steel metallurgist, but I think they actually measure permeability - they take not very large field, apply it to the sample and see what kind of magnetization is produced - it's supposed to be uniform if for example you apply the field along the easy axis (parallel to the sword?), but only if the sample itself is uniform.

Another way is to use X_Ray scattering or conductance or chemical tests - I think all these techniques are been used in the steel industry.

another interesting thing would be to try to achieve the true ground state in the sample by heating it up and cooling it down in the absence of external fields, with probably some random ac fields being applied to the body.

Concerning shape-dependent demag factors, there are programs like rkmag and oomf that allow one to simulate the magnetizations, so you should get the approximate picture of what kind of state you should have.

2. To Mare Rosu:

Thanx for the pictures,
The thing I would consider to be interesting is a conductance test. I don't think it can fire up with a simple resistometer, but it can be that if you place probes at about 5mm from each other on the dagger and move them alongside the dagger's surface that you will be able to see a significant change in the resistance along some set of points, which is possibly can be connected to the changes in the metall itself.

The problem is that not all steels are ferromagnetic, but they are all conductors, so unlike magnetism, you should not see a lot of difference.

P.S. I'm not a steel guy and not an experimentalist, so I really should not give any advices.

Sincerely yours,

K.Rivkin

[Jens Nordlunde]

I always thought ingots were like the round one you show Gene, but after having read Ann’s article in Minerva Magazine No. 13, issue 4, 2002, I was wiser, ingots can be found in many shapes and sizes, the ones made in Merv weighted according to Ann’s article about 2 kg.
Gene how many different ingots do you have, and do they have the same weight?
Is there any writing or marking on them? I remember to have seen a picture of a round ingot with some writing on it.

Ann, do you know if the shape of the ingots was a kind of ‘trademark’ for a region?
Would the kind of clay used, ‘porcelain’ clay vs. other types of clay, have any influence on the ingot?
Maybe we should start another thread on ingots.
Somewhere I saw, that in one of al-Biruni’s (973-1048) books, I think it must be in Kitab al-Hind that he describes iron/iron production(?) in India. Do you know if it is in this book?

Jens

[Mare Rosu]

JENS
This is the link to the wootz bar I had and made it into a Bowie by Al Pendray and also tested by Verhoeven. The end with the inscription is still with Pendray, at least it was the last time I saw him.
http://www.vikingsword.com/ubb/Forum1/HTML/002326.html
Gene