In article . com>, "Jude" > wrote:
>Phred wrote:
>> Recalling days of chem prac decades ago, I've sometimes wondered if
>> the "glass bead" principle would work with boiling eggs. Haven't
>> actually tried (don't have any glass beads -- and I suspect the lab
>> size would soon all be gone down the plug hole if I did have some
>> but maybe I will one day -- if I ever get around to buying a pack of
>> those cheap marbles from Coles Variety or wherever. They might be too
>> big relative to the size of the eggs though; could just get the whole
>> caboodle bouncing around!
>
>Explain the glass bead principle, please.

We used a few glass beads in flasks/beakers when heating solutions in
chem prac. The idea seemed to be that the bouncing beads would
prevent the container jumping around when the liquid started to boil.
(The beads themselves performed pretty well though.

The correct type of bead will also prevent superheating -- and could
be used in more modern times to prevent superheating of liquids in
microwave ovens. (Though I don't know of anyone who does this. ;-)

I was just wondering if their use would prevent eggs jumping around
and breaking during boiling. I note that someone else has assumed
eggs crack due to expansion of the air sac contained in them. I have
always assumed it was due to "bouncing". Maybe it's really a
combination of the two -- increased internal pressure combined with
physical stress on the shell. But I admit to bias towards the latter.

Cheers, Phred.

--
LID