Porcelain Bowl

A not-uneventful firing yesterday; at around 1220,when I start checking for cone 7,I saw that a chunk of roof had fallen smack onto the cones [further evidence of shoddy workmanship on my part],skittling cone 8,blocking cone 9 from view,and resting on cone 7- this at the top of the kiln. The bottom [which had caught up , due to steady rather than heavy reduction, a 90 degree difference at around 1000 ] looked fine,but not much cone action. The optical pyrometer [a neat and rare tool,salvaged from the demise of Naaman Porcelain Factory][by Sydney] seemed to be saying that top and bottom were very close and only just at 1200 degrees,but at 1240 on the big pyro cone 7 was still standing. The reading on the pyrometer seemed to me on the high side- I had placed a shelf almost touching the thermocouple's length,and thought that this might have led to a false high reading:at 1280,with what I hoped was cone 9 [having lost sight of cone 7] more than half over on the bottom,hoping that the top would be at least that hot if not hotter,I turned the kiln off.
This morning I saw that I had fired that rare animal,a kiln hotter in the middle than on either top or bottom [the top was a fraction cooler than the bottom,in the event]. In the past,I have cast doubt on people reporting this phenomenon,but now I'm a believer. In the middle of the kiln was this large porcelain bowl,making a very high shelf,and lots of heat had flowed there,at the expense of the top shelf. But overall the kiln fired well,lacking maybe 5-10 degrees for a really great firing.It held up well-no new cracks or droops,reduced better,and cooled slower. I'm relieved.
I realise [or suspect] that much of this is impenetrable to non-kiln-firers,who can skip these bits with impunity: I hope it will encourage other [and especially new] potters,who I hope may appreciate that kiln-firing is an inherently uncertain undertaking,regardless of the number of times one does it. This,of course,is what makes it so interesting. Shabbat Shalom!