Sweet’s indexed catalogue of building construction for the year 1906 (1906)
New York : Chicago : Architectural Record · leaf 281
DETAIL DRAWING Showing half-size longitudinal section of theNational System of Steel Puttyless Glazing Con-struction for Skylights Special Features of the National System—RolledSteel Supporting Bars; giving maximum strength with mini-mum weight, and also providing enclosed drainage gutters. Brass…
Building materials
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