thermometer probe in hallow egg full of water

I put a probe in a small jar of water. It's one of those little jars that pimentos come in, I poked a hole in the lid and the probe sits in that hole. Works really well, and it's washable.

 

I think the water would evaporate out threw the pores. I would use oil or something like it.

 

I read somewhere hair jelly in a plastic egg with a hole drilled in it. You full the egg hot glue it shut put the tempture thingee in it works good.
Yes I know thingee isn't right word but I can't spell or think right now.