Illinois Society of Architects · Chicago · leaf 229
gauge galvanized steel.The edges of such doors shall run in steelchannels not less than one and one-halfinches deep, and three-sixteenths of an inchin tliickness. (1) Such doors shall be hung on windingshafts and helical springs of sufficient slrengtli to counterbalance the door at anyposition, and… … Fisr. 32. Section o59j.Fig. 32. (H) 1/4 incli iron or steel sill. (F) 3 X 5 X % L riveted to iron sill. (G) % Inch l)oIt 18 o. c. Exception : Sill plates may be omitted where floorsare of concrete construction. number 12 U. S. gauge steel, which shall bereinforced around the edges by one and…
Architecture · Building · Architects
Internet Archive · University of Illinois Urbana-Champaign · Public Domain Mark 1.0. Free to use for anything.
![An illustration from [Graphophone patents] (1878)](https://img.insideoutlibrary.com/img/200/ia-graphophonepaten07unit-397-265.webp)