I'm sure thermal conductivity plays a major role, but I've heard that some
people who attempt walking on coal get burnt whilst others do not, even
though the time spent is very similar or perhaps even less. Perhaps it's
more like a combination of factors, including the quoted (yet unexplained)
mental concentration factor and variations in body morphology.
Owen Sant' Angelo
http://www.mapswebsite.cjb.net
----- Original Message -----
From: Barrett Dorko <[log in to unmask]>
To: <[log in to unmask]>
Sent: Wednesday, July 19, 2000 1:06 PM
Subject: Re: walking on coals
> The ability to walk on hot coals doesn't have much to do with the nature
of
> the feet, but with the nature of thermal conduction between wood coals (or
> porous rock) and anything touching them. While the thermal energy is very
> high and is certainly sufficient to burn flesh, wood coals conduct that
> energy slowly enough to allow walking over them without any damage.
Imagine
> a cake in the oven. Reaching into the hot air around it can be tolerated
> for several seconds, even touching the top of the cake is not dangerous,
> but you can't touch the pan. All have the same thermal energy, but conduct
> it at markedly different rates.
>
> It is not necessary to break the laws of physics to walk over hot coals,
> though the courage to do it if you don't know them might be difficult to
> muster. This is where the emotional appeal by those involved in this comes
> into play.
>
> Barrett L. Dorko, P.T.
> <http://barrettdorko.com>
>
>
>
>
>
>
> At 09:00 AM 7/19/00 +0000, you wrote:
> ><FontFamily><param>Times New Roman</param>This query is unrelated
(almost)
> >to physiotherapy practice, but I`m sure
> >
> >someone out there will have the answer.
> >
> >
> >
> >How do people walk on red-hot coals and not get injured?
> >
> >
> >
> >
> >Thinking about this, I`m sure that higher centre control allows the
> >
> >individual to undertake the activity, ie. they psyche themselves up to do
> >
> >it and then don`t hang around but walk quite quickly, but i don`t think
> >
> >that this explains the lack of injury, other than minor burns where coals
> >
> >get stuck between toes.
> >
> >
> >
> >I`m sure that it must be to do with the thermal conductivity of the skin
> >
> >on the feet, particularly the outer epidermis which lacks a blood supply,
> >
> >and conducts heat more poorly than the deeper dermis. The only values on
> >
> >the thermal conductivity of skin give a range (0.33-0.96 W/m/c)
> >
> >
> >This poor conductivity and the small period of time that the feet are in
> >
> >contact with the coals allows the activity to be carried out without
> >
> >tissue damage.
> >
> >
> >
> >Is this a correct assumption?
> >
> >
> >Can anyone else provide any further explanations for this apparent
> >
> >extraordinary feat?
> >
> >
> >
> >Regards
> >
> >
> >
> >Grahame
> >Pope<color><param>0100,0100,0100</param><FontFamily><param>Arial</param>
> >
> ><nofill>
> >/*\/*\/*\/*\/*\/*\/*\/*\/*\/*\/*\/*\
> >Grahame D Pope, MPhil, MCSP, Dip TP, Cert Ed.
> >Lecturer
> >Division of Physiotherapy Education
> >Clinical Sciences Building
> >University of Nottingham
> >City Hospital
> >Nottingham
> >NG5 1PB
> >0115 840 4879 Fax 0115 840 4893
>
>
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