Table 434 

 THE REFLECTING POWER OF BUILDING MATERIALS 



3*3 



Filter I (1.78/i), Chance's blue-green contrast filter No. 6, 3.3 mm thick, with their orange 

 contrast filter No. 4, 2.7 mm thick. Filter II (0.84/u), 2 cm water-cell, Chance's orange 

 contrast filter .No. 4, and cobalt-blue glass, 1.8 mm thick. Filter III (o.6i,u), 1 cm K 2 Cr 2 7 

 sol. (72 g/1) and I cm cell CuS0 4 sol. (57 g of hydrated salt/1). Filter IV (0.50^), 2 cm cell 

 CuS0 4 sol. sat. at 14. 2° C. Gold film: radiation from " pointalight " through a thin gold 

 film can be used in place of sunlight (compare with computed values). (Beckett, Proc. 

 Phys. Soc, 43, 227, 1931.) 



Description 

 Magnesium carbonate 



CLAY TILES 

 Dutch: light red. 



Machine-made: red 



red 



lighter red. . 

 " dark purple. 



Hand-made: red 



red-brown 



CONCRETE TILES 



Uncolored 



Brown 



Brown : very rough 



Black 



SLATES 

 Dark gray: smooth 



fairly rough 



rough 



Greenish gray: rough 



Mauve 



Blue-gray 



Silver-gray (Norwegian) 



OTHER ROOFING MATERIALS 



Asbestos cement: white 



red 



white 



Enamelled steel: 



green 



red 



blue 



Galvanized iron: new 



very dirty. . . 



whitewashed . 



Special roofing sheet : brown . . 



green . . 



Bituminous felt 



Aluminized felt 



Weathered asphalt 



Roofing lead: old 



BRICKS 



Gault: cream 



Stock: light fawn 



Fletton: light portion. . . 

 " dark portion. . . 



Wire cut : red 



Sand-lime: red 



Mottled purple 



Stafford: blue 



Lime-clay (French) 



Smithsonian Tables 



