National boilers, radiators, and specialties: catalog no. 26 (1920)
National Radiator Company · National Radiator Company · leaf 47
Openings for fresh-air inlets from back of radiators are asfollows: 5-section, 4^4 x 334 inch6-section, 7J4 x 3J4 inch7-section, 734 x 334 inch8-section, 834 x 334 inch9-section, 10^4 x 334 inch 10-section, 1034 x 334 inch11-section, 1234 x 334 inch12-section, 1234 x 334 inch13-section, 1634 x 334…
