National boilers, radiators, and specialties: catalog no. 26 (1920)
National Radiator Company · National Radiator Company · leaf 66
ing of windows and doors does not in any way affectits proper function. It operates on the fraction of an ounce pressure. It closesagainst the loss of steam, the loss of water and the return of air. It saves coal and maintains the efficiency of every section ofthe radiator—the last as well as the…
