Ok, to get away from bottles:

As most will be aware by now, I am writing a report on a late 19th century
brick factory that my company excavated at Leetsdale, PA, called the Harmony
Brickworks. One of our most significant finds during excavation was that the
factory employed a sub-floor flue system for distributing heat in their dry
floor complex. These systems are referred to as "hot floors" in the
contemporary literature (such as the trade journal "Brick"). The sub floor
flues are essentially just brick alignments one course wide laid end to end
and extending the length of the hot floor. We have examples of both a floor
heated by coal and gas fired furnaces and also a floor heated by steam shot
into the brick flues through small holes in steam pipes aligned with the
flue entries.

I've looked and our historian has looked for any archaeological references
to hot floors, so I can state how "unique" this factory is in the
archaeological literature, and also of course to compare it to other
examples. I can't find anything in the archaeological literature specific to
hot floors (Gurcke mentions them breifly in his work) and the contemporary
literature we've been able to find do not discuss anything similar to what
we encountered. If anyone has excavated a hot floor, I would love to hear
from you.

Thanks in advance,
Andy

Andrew R. Sewell, MS, RPA
Principal Investigator
Historic/Industrial Archaeology
Hardlines Design Company
4608 Indianola Avenue
Columbus, Ohio 43214
(614)-784-8733
fax: (614)-784-9336
www.hardlinesdesign.com