eac@drux3.UUCP (04/16/84)
In reply to the article that questioned the fact that pouring hot water
into a cold china pot will cause cracks:
It doesn't have anything to do with the tea! Cracking will occur to
pots, cups, even metal if the temperature change is radical enough
to stress the material. You can even hear cups cracking if you
pour boiling hot water in. Most of the time it is only a hairline fracture
which will be stained by the tea or coffee, resulting in fine brown
lines inside your cup or pot. If you don't believe this, start looking
in the bottom of your cups. By the way, to keep cups from cracking,
put a spoon in the cup, then pour the boiling liquid in so that
it touches the spoon first.
Betsy Cvetic
ihnp4!drux3!eac
303-538-3406
P.S.--to you doubting Thomases, try this experiment--drain the water
out of your car engine, let it run until it gets very hot, then pour
cold water on it. (This case is, of course, more extreme, but the
principle is the same)peters@cubsvax.UUCP (Peter S. Shenkin) (04/17/84)
I'm not willing to argue that boiling water *can't* crack porcelain.
If it does to some types, I stand corrected.
What I *will* argue is that pouring boiling water in the pot to pre-heat
it won't prevent the pot from cracking, as others tried to argue. I
also agree with the spoon trick.
Incidentally, Thin pots should have less of a tendancy to crack under
thermal stress than thick pots. Also, if it makes noise, it doesn't mean
it's cracking; just the motion that differential expansion makes causes
noise (as in a car engine cooling down).
{philabs,cmcl2!rocky2}!cubsvax!peters Peter S. Shenkin
Dept of Biol. Sci.; Columbia Univ.; New York, N. Y. 10027; 212-280-5517
"In accordance with the recent proclivity for clever mottos, this is mine."