On Thu, 31 Oct 2013 12:26:26 -0400, Ed Pawlowski > wrote:

>On Thu, 31 Oct 2013 06:45:45 -0700 (PDT), Helpful person
> wrote:
>
>>On Thursday, October 31, 2013 12:38:48 AM UTC-4, Ed Pawlowski wrote:
>>> On Wed, 30 Oct 2013 21:16:42 -0700 (PDT), Helpful person
>>> >On Wednesday, October 30, 2013 3:38:36 PM UTC-4, Brooklyn1 wrote:
>>>
>>> >> Flatness doesn't matter for even heating with a gas stove. Most
>>> >> quality cookware is designed with a slightly concave bottom that will
>>> >> become flat when metal expands as it's heated.
>>>
>>> >Why will it flatten when heated?
>>>
>>> Metal expands when heated. It will sort of push the sides out and
>>> flatten. Some pans are designed that way to allow for the expansion.
>>> A metallurgist can explain it better.
>>
>>Rubbish.

>You say rubbish, yet you offer no better explanation. What does that
>make you? Explain or STFU

There are many web sites that concur with my explanation, this one is
concise:
http://www.meyergroup.co.uk/cookware...14.html?Lang=1