The New York City House: Gorgeous Period Details

Factories used mechanized casting to create elaborately designed brass, bronze, and iron house parts like doorknobs, window hardware, and vent covers. This vent brought warmth to the first floor from the house's original coal furnace, but there was no forced air. "It operated by the simple principle of 'hot air rises,'" says TOH plumbing and heating expert Richard Trethewey.