TABLE 232. 

 THERMAL CONDUCTIVITIES OF INSULATING MATERIALS. 



215 



Conductivity in g-cal. flowing in i sec. through plate i cm thick per cm^ for 1° C difference 

 of temperature. 



Material. 



Remarks. 



Air 



Calorox 



Hair felt 



Keystone hair 



Pure wool 



It (( 



(( <( 



t( u 



Cotton wool 



Insulite 



Linofelt 



Corkboard (pure) 



Eel grass 



Flaxlinum 



Fibrofelt 



Rock cork 



Balsa wood 



Waterproof lith 



Pulp board 



Air cell | in. thick 



Air cell i in. thick 



Asbestos paper 



Infusorial earth, block . 



Fire- felt, sheet 



Fire-felt, roll 



Three-ply regal roofing. 

 Asbestos mill board . . . 

 Woods, kiln dried: 



Cypress 



White pine 



Mahogany 



Virginia pine 



Oak 



Hard maple 



Asbestos wood, sanded. 



Horizontal layer, heated from above. 

 Fluffy, finely divided mineral matter. 



Felt between layers of bldg. paper. 

 Firmly packed. 



a it 



Loosely packed. 

 Very loosely packed. 

 Firmly packed. 



Pressed wood-pulp — rigid, fairly strong. 

 Vegetable fibers between layers of paper — 

 soft and flexible. 



Inclosed in burlap. 



Vegetable fibers — firm and flexible. 



Rock wool pressed with binder, rigid. 



Very light and soft. 



Rock wool, vegetable fiber and binder, not 



flexible. 

 Stiff pasteboard. 

 Corr. asbestos paper with air space. 



Fairly firm, but easily broken. 



Asbestos sheet coated with cement, rigid. 



Soft, flexible asbestos. 



Flexible tar roofing. 



Pressed asbestos, firm, easily broken. 



Asbestos and cement, very hard, rigid. 



Dickinson and van Dusen, Am, Soc, Refrigerating Eng. J. 3, Sept. 1916. 

 8UITHS0NJAN Tables. 



