[TowerTalk] original source of "avoid sharp bends" in lightning

[Jim Lux]

On 4/12/12 7:00 AM, David Robbins wrote:
>
> If i had to guess i would start looking at old installation
> instructions for lightning rod installation.  Did anyone make a
> do-it-yourself lightning rod kit?  maybe an old Sears catalog or farm
> supply mail order catalog would have a kit like that.

yeah.. I'm actually looking for Franklin's instructions: after all, he's 
the guy who popularized it, if not invented it.

>
> As far as why I would guess when lightning rod conductors ran down
> the outside of the buildings someone may have noticed corona or
> streamers from sharp bends in the wires.  Someone may have also
> noticed side flashovers from sharp corners to other objects, again
> more due to corona at the bend than inductance.  A few observations
> like that may have led to an admonition to avoid sharp bends in the
> wire.  that would have been long before the concept of inductance was
> thought of and would have been an easily observed phenomenon.
>
An interesting point.  Back then, the conductor (if it was even a wire) 
would likely have been iron, I think, and probably brittle, as well. 
Maybe it's more to do with the ability of a blacksmith to draw wire or 
make smooth bends.

So basically encapsulating empirical observation  with "standard 
manufacturing practice" of the 18th century, and then "standards 
inertia" takes hold.

The analysis is complex to show that you don't *need* to do it that way, 
so why not just stay with what has worked for a century.