Topic: Glass battery jar lid?

[NevB]

There are lots of online images of glass fruit/bottling jars which look similar. Some have rubber seals some don't and they are secured with metal clips/clamps.

[ian.macky]

It does also look like a canning jar lid, except those are sealed with a rubber gasket, and the older kind sometimes use some sort of metal clamp (of which many designs are patented)...  but they're meant to be sealed tight.  I don't see any trace of a gasket on this one, but you usually don't.  I've yet to see any with a rubber plug and a vent hole, either.  Usually you seal them tight then heat (sterilize) them in a double boiler or pressure cooker, and you definitely keep them sealed until ready for use.  Has anyone seen one with a little vent hole?  I haven't.  The construction of the vent hole seems strangely and unnecessarily complicated.

Here's another pic:

[Ekimp]

Hi, possibly the top part of a two part battery rest https://glassian.org/Battery/British/t30.jpg

That website home page: https://glassian.org/insulator.html

[ian.macky]

Battery rests are meant to insulate old glass batteries, and are sometimes designed to contain any nasty chemicals that might leak out, so they don't have any sort of through hole.  See Battery Insulators, Oil Insulators, and Chloride Accumulators (PDF)

BTW, I am glassian.org