These Topics of Historic Interest are posted here to facilitate research and scholarly debate:

BROAD GLASS/ An 18th Century method of cylinder glass production to yield mouth-blown sheet glass. Plates from Diderot's Encyclopedia of Trades and Industry
Head of Christ France ?, Normandy or Lorraine? 16th century (an earlier article says 1500-1510) Pot metal and white glass with silver stain and sanguine 34x28 (13 3/8 x 11) The upper part of the halo is a restoration; manel may be a composite. 03.SG.9 Glencairn Museum
A visit to Glashutte - archaeological dig site of a medieval German glass factory
Medieval Glass Making exhibit in the open air museum at Hessenpark Germany
Illustrations of ancient glass blowing