To expand on what Colin said ......
It is the integrated amount of current through the heart muscles  
( over a 1 second period approximately )
that disrupts the heart beat.  You can also start a non-working heart  
this way ( sometimes )
Thus the more voltage applied to push current near the heart, the  
actual path the current takes ( does it go through the heart  
muscles  ? ),
Applying voltage from sweaty hand to the other sweaty hand does a good  
job of directing current near the heart.  More voltage helps push
the current through the skin ( which is often a good insulator when  
dry ).
A good plan for stopping your heart is to push needles into your chest  
on either side of the heart.   Now the current can flow easily through  
your heart muscles.  Static discharge ( high voltage , low amount of  
total electrons ) may stop your heart in this case.  A nine volt  
battery might work too ( lower voltage, more electrons available ).     
The crucial issue is 1) is there a good path for the current to flow  
through your heart muscles     2)  Is there enough voltage ( push ) to  
ensure adequate current flow given the resistance of the path.

 From the outside of the body, it is useful to have very high voltage  
sources that can supply a lot of current.   Apply that from arm to arm  
or from front of chest to back of chest.  Use liberal amounts of  
conductive goo on the skin.   Better yet, stick conductive probes into  
your chest.  Some of the current flowing through your body is bound to  
intersect with your heart.

By the way,  does anyone know if being electrocuted is painful ?

Gus

> On Jul 5, 2009, at 1:48 PM, cdb wrote:
>
>
>
> :: And why is it that if you touch a 120 V source, you die - yet a
> :: 15000
> :: V static shock merely stings?
>
> Amount of current through the the body and the duration of that
> current, as well as the impedance that the current source has.
>
>
>
> Colin
> --
> cdb, colin@btech-online.co.uk on 6/07/2009
>
> Web presence: www.btech-online.co.uk
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