Topic: How was this hourglass made?

[glassobsessed]

I am curious to know how hourglasses like this are made. How do they get the sand inside and how is the tiny hole between the two sections formed?

This particular one is large at 23cm tall but if you used it for your eggs they would end up like concrete - it takes about 45 minutes for the sand to run out. Perhaps it would work for ostrich eggs....

John

[chopin-liszt]

I think 45 minutes is about right for an ostrich egg. Honest!  :sun:
I was watching a programme about non-chicken-egg eating recently!

[rosieposie]

There might be an answer to your question in this, and it makes fascination reading as well.

http://www.hourglasses.com/

[glassobsessed]

I guess a single ostrich egg could feed a few people...

Thanks Rosie, I gleaned that the sand may not actually be sand but could be ground rock of some sort or perhaps even glass, granule size appears to be very important as does purity. Sounds like our ancestors used to 'waste' an awful lot of wine boiling their sand nine times.

The glass vessels shown have plugs or caps on the end so that sand can be added or even removed, this hourglass is completely sealed and as far as I can tell the sand must have been added to one of the chambers as it was being made.

[rosieposie]

I did wonder if someone on that website might have an answer.....is it worth writing to them ?

[glassobsessed]

Worth a try, I will ask, we may need the insight of a glass maker.

John

[Frank]

Blow a long bubble, in this case dip moulded to get the ribs. Transfer to punty and shape it, a small hole left in the end for inserting the sand later, the hole being easily sealed.

Normal sized hourglasses are done entirely at the lamp.

[rosieposie]

You make it sound so simple Frank.....think I'll set up a production line in the shed!!

That one is particularly spectacular though.
Rosie. 

[glassobsessed]

Thanks Frank.

So, long bubble crimped in the center, poke a hole with a bit of wire in the middle, add sand and seal up.

Simple, just like Rosie said...

John

[rosieposie]

Simple, just like Rosie said...

John

If only it were!  :usd:

Rosie.