“Conservatory interior looking southwest,” Rockwood, near Wilmington, Delaware, 1982, by David Ames, via an Historic American Buildings Survey (HABS), Library of Congress Prints and Photographs Division (all photos here).
Built between 1851 and 1854 in the Rural Gothic Revival style, the estate still exists as the Rockwood Park and Museum.
Designed for Joseph Shipley, a member of one of the leading Quaker mill-owning families in the area, Rockwood is an unusually complete and effective statement of early Victorian taste in the tradition of A.J. Downing and John Clauduius Loudon. The mansion house reflects both early Victorian romanticism and the picturesque merger of irregular architecture and naturalistic landscape. When taken in conjunction, the architecture, the plan, the garden and the remaining furnishings depict a total physical sensibility that is fast vanishing from America.
— 1986 HABS report
“Conservatory, detail of cast iron columns looking northeast.”
“Conservatory, roof and northwest wall looking north.”
More winter gardens are here. And more abandoned greenhouses here on the blog Messy Nessy Chic.
enclos*ure 
Ack! Love it. It would be so fabulous to play with plants in the wintertime!
What a luxury to have a place like this — heating bills aside. It’s so great that it still exists as a museum.
Oddly, I know we have both had winter houses similar….in imagination at the minimum.
Garden & Be Well, XO Tara
I think if I really had this conservatory, I’d be tempted to leave it empty — or almost.
So much more appealing than my winter garden; that is a snow-covered garden.
A very fine, light snow fell here in Stutgart yesterday — the first snow falling that we’ve seen in about 4 years. It’s so beautiful in the trees.