[Sca-cooks] pie bird/pie funnel?

[Stefan li Rous]

Odette suggested:
  <<< You might try an old fashioned pie bird or pie funnel.  Besides  
helping
vent the steam to keep the top crust flaky and tender, they also help
keep  the top crust from sagging.  >>>

This is the first I've heard of such an item. How big are these? Do  
you leave them in the pie during baking to help vent the steam? What  
makes them different from any funnel you would find in the store? And  
lastly, what's the earliest date for their use?

Thanks,
    Stefan
--------
THLord Stefan li Rous    Barony of Bryn Gwlad    Kingdom of Ansteorra
    Mark S. Harris           Austin, Texas           
StefanliRous at austin.rr.com
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