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manometers and lists

updated sun 31 aug 97

 

Joseph Herbert on thu 28 aug 97

I have thought, since high school physics, that open tube manometers were
pressure measuring devices that depended on the pressure of a column of a
liquid (either water or mercury) to balance the pressure to be measured. If
this is true, the total height of the column of liquid - that would be the
vertical distance between the two liquid surfaces, represents the pressure
being measured. This could be in inches of water or inches of mercury. 30
inches of mercury representing about 15 psi, 27 inches of water representing
about 1 psi.

There is a possibility that commercially prepared manometers with a zero
"setting" use a scale that is calibrated in "inch increments" that are
actually = inches long. Since the one side of the manometer is forced down
as much as the other is forced up, measuring the number of half inches one
side goes up gives the actual reading in full inches. This allows the math
impaired to read a single scale to get a value without having to subtract
numbers of the single digit variety from one of the double digit variety,
either of which might include a fraction.

While we are making lists, I would like to have my name added to the one that
says it s hard to make a living from pottery. I am not a college professor
so I may not qualify, but I feel that telling a 19 year old that it is
impossible to make a living from clay is correct 99.95 percent of the time.
So five in ten thousand might be able to. That is similar to the odds of a
high school football or basketball player making it to the pros. For the
same odds, the sport things pay lots better.

We have had this making-a-living discussion before. In the previous round
Jack Troy - a college professor - held that he found it relatively easy to
make a living from clay. He did not mention that he supported himself for
twenty years as an English teacher while getting to his current elevated
status. There are a number of full time clay workers on our list, there are
a greater number who are not on the list because they can not afford a
computer and email service. Most of us work at other things to support our
clay habit.

An additional thing to remember is that college programs are intending to
produce ARTISTS. These may be ceramic or of some other variety. Potters are
not ARTISTS, ask any MFA program. It is interesting that it is no easier to
make an actual living as an ARTIST than it is as an actual potter. I agree
that it is possible to be a working potter who can make a house payment, make
a car payment, buy health insurance for the children, and afford to take a
vacation every five years. I just believe it is really rare. Really Rare.
And I don t think it is wrong to tell a person about the difficulties their
choices might present in their future lives.

We could also make a list of persons who encourage ignorance in others only
to be brought up short by ignorance themselves. On second thought, there are
no people like that so there can be no such list.

Joseph Herbert
JJHerb@aol.com