Sweet’s indexed catalogue of building construction for the year 1906 (1906)
New York : Chicago : Architectural Record · leaf 556
(Patent Applied For.) Figs. 5 AND 6. THE NORWALL PACKLESS QUICK OPENING RADIATOR VALVE and the job as a Vacuum job is a failure until the leaky Valves are repacked. AVacuum job may be perfect and absolutely tight in all its other joints, and yet ifequipped with packed Radiator Valves it will soon…
Building materials
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