You might already know this, but if not just for info on the Aetna Glassworks:
According to the Centro Midland Metro Phase 1 extensions assessment document dated 16 March 2009 the Aetna Glassworks, established in 1836/37, was still there in 2009 and:
"The Aetna Glassworks was situated to the south of Broad Street, adjacent to Gas Street Basin"
and
"is a locally listed building although even this factory had its furnace dismantled in the 1920s. The glassworks all shared a distinctive feature, the glassworks cones, which would have dominated the skyline in this eastern area of the city. The primary purpose of these distinctive tall, brick-built truncated cones was to provide an updraught for their circular, centrally positioned furnaces, and to provide working space and cover for the glassworkers"
Viv