Borderline wrote:
>> I really like the pint-and-a-half mason jars that some speghetti
>> sauce comes in. ...................
>
> Yeah. Classico spaghetti sauce comes in square Atlas Mason jars. The
> ones I like are clearly marked with levels at 4oz, 8oz and 12oz and
> there is room above the 12oz level for another 3 oz flush with the top
> of the jar, about 15 ozs, perfect size for jams.
>
> When they make these jars, they must brand them when they are at glass
> melting temperatures, since all the markings are pressed right into the
> glass.
Generally molten glass at the leather stage is blown into a steel mold.
The lettering is in the mold. Bottle and jar makers have been doing that
for at least 200 years. Early on they were hand blown into the mold,
nowadays it's all machines.