Re social history of brass/iron beds:

See some of the big furniture references, eg Edward Joy, Pictorial
Dictionary of British 19thC Furniture Design, London, Antique Collectors
Club, 1977, for metal beds back to the 1830s (Loudon).

They were not necessarily poor people's furniture, but portable - for
military/naval/explorer/colonist-settler types.

You are right to think that there was a health aspect to their promotion.
Being light and able to be taken apart, they could be cleaned of bedbugs
and other nasties lurking in the joints.  The comparitive airiness of metal
beds also made them sound healthy (or in the lingo of the late 19thC,
'sanitary').

Siegfried Giedion may touch on portable furniture in Mechanisation Takes
Command.

Cheers

Linda Young
Cultural Heritage Management
University of Canberra
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