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1869.] Descriptions. 555 A A A— Hot Air Flues. SECOND STORY. B B— Foul Air Shafts. PLAN OF SECOND STORY AND BASEMENT,— SHOWING THE SYSTEM OF VENTILATION,— IN THE MUNICIPAL HALL: PITTSBURGH, PA. By Lewis W. Leeds.
1869.] Descriptions. 555 A A A— Hot Air Flues. SECOND STORY. B B— Foul Air Shafts. PLAN OF SECOND STORY AND BASEMENT,— SHOWING THE SYSTEM OF VENTILATION,— IN THE MUNICIPAL HALL: PITTSBURGH, PA. By Lewis W. Leeds.
