Wizard Of Lids

https://www.insulators.info/general/glassfaq.htm

This excellent historical glass manufacturing information is focused on insulators, but also applies to what we see in the jar collecting hobby. Enjoy!

Frequently Asked Questions about Molding Glass Insulators What we call 'underpours' are hardly ever caused by an insufficient volume of glass in the mold. They are usually caused because the glass cools before it can be squeezed into the small areas of the mold. This is why underpours occur on the base and inner skirt region. This is the area where there i...

Crowleytown Mason Patent Nov 30th 1858 are some of the very oldest fruit jars. They are sort of squarish with high, well defined shoulders. The jars in this photo are NOT Crowleytown jars. Being the jar heretic that I am though, I've created these 2 caricatures of them. They would be roughly the size of a pint and a full gallon. Pictured with a half gallon jar to better show size. I don't think there are any legitimate gallon size Crowleys out there. Only seen here. Enjoy!

Canadian jars (shipped from Canada) are less affordible now...