RE: Variable Capacitance and Inductance

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Malcolm Watts by way of Terry Fritz <twftesla-at-qwest-dot-net>" <m.j.watts-at-massey.ac.nz>

Hi Dave,

On 22 May 2002, at 19:30, Tesla list wrote:

> Original poster: "David Thomson by way of Terry Fritz
<twftesla-at-qwest-dot-net>" <dave-at-volantis-dot-org>
> 
> Hi Malcolm,
> 
> >The quote from Tesla contains excellent examples of limited knowledge
> and/or misinterpretation of results.
> 
> Richard Hull agrees with Tesla, why shouldn't you?  

He doesn't always, and if there is any doubt about that I would be 
happy to bring his Guide in and quote the page in questiuon.

In Hull's notes on CSN
> for November 14 he writes, "Tesla would later say in a published newspaper
> article (January 30, 1901 New York Sun [same article I posted]) that his
> Colorado experiments had shown that some of the assumptions of the
> scientists of his day about the ideas concerning elevated capacities were
> flawed.  His CSL studies had shown a definite difference between computed
> and measured values of free standing capacitive surfaces."
> 
> And if you read the CSN, you will see that the measurements of capacity
> changed from day to day even when using the same measurement methods.

I don't have a problem with that. Did I say that I did? Quote the 
passage please.
 
> Richard Hull notes these daily changes, too, as in his comment of Tesla's
> November 7 entry.

Yes. But he also noted that on one occasion at least, Tesla claimed 
some massive increase in capacitance with a relatively tiny increase 
in height (which he vehemently took issue with). 
     There are two issues to be dealt with I think: the first is why 
capacitance should increase with height (for an isolated terminal) 
and secondly, just how isolated was the terminal in reality? I got 
the distinct impression that it was connected to his apparatus by a 
piece of wire (how else did he measure it if not?) which is not an 
isolated situation at all. Anyone who has gone seriously into 
measuring properties of Tesla type resonators will understand the 
difficulties.

> As far as questioning the accuracy of Tesla's work, he spent an entire month
> of 16 hour days studying this.  It would be arrogant to assume Tesla did not
> understand such things as the capacitance of wire lengths (see CSN page 288)
> or would have overlooked the humidity in the air.  Although Tesla mentions
> the effect on resonance of moisture at sea and in harbors, all his
> experiments were conducted in the dry autumn air of Colorado at an elevation
> of nearly 1 mile above sea level.

Questioning interpretation of some results does not amount to 
arrogance I would suggest. Like all human beings (you and I 
included), Tesla was not without error. I would be interested to see 
your explanation of why a truly isolated terminal should increase its 
capacitance as it is moved away from the ground. I have a right to 
question that which to me does not make sense. So does everyone else.

Malcolm